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Clandestino
25th Aug 2011, 00:19
Procedure that required setting 5°/CLB by heart was in force at the time of the accident. Page 59 of interim 3 report in English refers.

I see there's fear that it's unsafe and leads to zoom climbs ending in stalls.

It is not and it does not.

You will climb out of cruise condition but if your significant cockpit other fumbles with QRH for a half an hour, you will simply and gently level off at altitude where power required meets power available at 5° AoA. There's no aeroplane that can not sustain 5° AoA below Macrit, from Sopwith Camel, to Belanca Airbus, to CitationJet, to B747, to whatever and with thrust to weight ratios and of modern passenger jets, you will be far fom Macrit at 5° AoA. Do you understand that, for all practical purposes*, your AoA is difference between pitch and flightpath and in level flight AoA=pitch?

Does anyone have anything to add to this except his feelings and suspicions? Like arguments?

Granted, there's no need to go climbing but procedure is not about maintaining altitude. Speedwise, it gives you safe pitch and power for any weight, until actual settings are taken from the table. 5/CLB is just temporary measure and IMHO can be skipped if one knows his cruise power settings and attitudes for different weights by heart or if he was in stable cruise condition and just maintains last pitch and power. However, this would be overriding the prescribed emergency procedure and one must be better sure he knows what he is exactly doing.


*disregarding wing incidence and vertical air currents

Lonewolf_50
25th Aug 2011, 00:28
Clandestino, a couple of threads back, HazelNuts39 posted a chart that compared stall AoA to mach and altitude, and it appears that you either get stall warning, or stall ( can't recall which thread to look in) at about 4. (Big diff, obviously,, between warning and stall). Something disturbs me about your choosing to champion "rote rote and more rote" as a solution.

What is the point in climbing an aircraft to trouble shoot a problem when you have fewer parameters to mess with by trouble shooting it while straight and level?

Why add a needless performance parameter when trouble shooting a malfunction?

I am at a loss.

Look at what happens with the advocacy of "keep it at five degrees until infinity." (Or the bloody PNF finally gets the QRH out and opened to the correct page).

Pitch up to 5 deg, and leave it there.

OK, while trouble shooting UAS, you get a stall warning. (See above, if I can find that table, I'll repost it).

Now what?

Well, lower the damned nose, you just got a stall warning.

OK, warning goes away, but where should you now assign the nose? What pitch angle.

Doesn't it bother you that you got a stall warning for no good reason by keeping the nose up in a pitch climb for no good reason?

Result is that you just gave yourself a multiple malfunction, so rather than dealing with one, you are now dealing with two.

Ever heard of anyone doing that?

(The "you" here isn't Clandestino, it's a generic "you" pilot in the audience going through this drill).

Coagie
25th Aug 2011, 00:43
Jcjeant,
You brought it up about the inadequate search. Sometime in the last year, it was published that the french nuclear submarine was listening for the ping of the black boxes incorrectly with their sonar. The ping of the black boxes is at 37.5 khz, which, of course, is beyond the range of human hearing. A 5th grade science student would have known that! Just wanted to give an example of how pathetic the search effort was.
A great deal of money was spent to just go through the motions (sending a "nuclear" sub sounds impressive). It was not in France's best interest for the black boxes to be found sooner rather than later. The people were already dead, and Air France lawyers, Airbus lawyers, and the BEA were all on the same page. I remember a bunch of Airbus military tankers were about to be sold. Sure, everyone wanted to know what happened to AF447, but not just yet, and a couple of years for emotions to cool could help minimize lawsuit payouts as well.
Hate to be such a cynic, but it's life in the real world.
Thankfully, the BEA, Airbus, and Air France may not be on the same page any longer, and the industry can learn from this tradegy.

DozyWannabe
25th Aug 2011, 01:05
@Coagie:

In 1988, the USS Vincennes incorrectly identified an Iran Air A300 as an Iranian Air Force F-14 and shot it down. In 1985, the joint US/French Titanic expedition incorrectly identified an immediately strong sonar reading at the beginning of their search pattern as an equipment malfunction and spent weeks headed in the opposite direction of the wreck, and it was only when - in a last-ditch effort - they threw all the video imaging equipment at the area a short distance from their point of origin that the wreck was actually found.

All I intend to illustrate with this is that neither military operations nor deep-ocean exploration are immune from mistakes, and before throwing accusations of conspiracy around, Hanlon's Razor should apply:

Never attribute to malice that which is adequately explained by stupidity.

Or even miscommunication and bad luck.

Chu Chu
25th Aug 2011, 01:42
Coagie, what I read was that Emeraude's sonar wasn't initially optimized for 37.5 KHZ, not that it was completely deaf at that frequency. Just because you can hear the pinging in a WWII movie it doesn't necessarily follow that modern sonar is limited to the range of human hearing.

PJ2
25th Aug 2011, 01:48
Clandestino;
I see there's fear that it's unsafe and leads to zoom climbs ending in stalls.
Let's start from a different point, as something of a counterexample.

Let's say the A330's cruise pitch attitude is a nominal 5deg and a UAS event occurs and the crew executes the memorized items. I think then, you and those here who disagree with the views that I have expressed concerning this procedure would find agreement, as nothing would occur - the airplane would remain essentially level, (given the vagaries of turbulent flight).

So why isn't there broad agreement on keeping level flight? What is the actual Airbus justification for pitching the aircraft up to 5deg? I've heard the justifications but I haven't seen the sources. I have provided sources for everything stated in favour of the argument that the drill is confusing at best and incorrect or executed incorrectly, at worst.

Your comment in your post to which I originally responded does make the point that these drills are created by test pilots and disagreement with same is not something to take lightly. As a general rule I think that is a good principle - who are we to argue - generally?

But as you know very well from CRM principles, in this business if one is uncomfortable with something, regardless of who said it, who did it, or who wrote it, one speaks up and sorts it out and if one is wrong, so be it, no harm done. The airplane only respects the laws of physics. This accident is ample demonstration of that fact.

Given the example at the beginning of this post, I think it can be said that the issue isn't the pitch, (and I think you know this) - the issue for me is the destabilization factor. The point I am focussing upon isn't the idea of not being able to control all this and sort the climb and the recovery to stabilized flight. By pitching up, one adds to one's problems exponentially while one is trying to sort the problem instead of having a stable platform from which to execute the remainder of the checklist.

It simply makes no sense to alter anything because, given everything else equal nothing has occurred to the airplane which requires an immediate "correction". I commented years ago that I cannot imagine any pilot actually doing this and nothing I've read, seen or heard has altered this view because there is no good reason to do this in a transport aircraft - it simply leaves one in no-man's land.

One doesn't even have to know what one's airspeed and thrust setting were before the loss of speed indications...one just keeps the same attitude and when happy, just pulls the thrust levers out of the CLB detent and back to the thrust setting that was being indicated while the thrust was in the THR LOCK mode.

There are no examples that we can reference in the 30+ UAS events listed in BEA Report 1, in which the crew pulled the aircraft up in response to a loss of all airspeed indications.

As I have worked on this I have come around to understanding what the drill and the FCTM says and by all indications, the memorized items apply first, then the level-off, (which I think is crazy and wrong, but I nevertheless wish to argue against it on its lack of merit), but I have posted the relevant sections which govern how this drill is to be done (as stated in two airlines' FCTMs, probably not all airlines and probably not from Airbus...CONF iture responded very early in this discussion with this point, and it will be of interest to learn how AF taught this drill and what guidance is offered in the AF FCTM on the point).

The relevant sections from the two FCTMs I posted indicate that while the memorized items are to be done "immediately", the airplane is to be returned to stabilized flight as quickly as possible and troubleshooting begun before a speed limit is exceeded. Now...I am wondering why a drill should put an airplane in such a situation? Doesn't this have the potential for creating a bigger problem than it is designed to solve?

Hope this is takes the discussion forward, and thank you for commenting.

Lonewolf_50
25th Aug 2011, 01:55
For Clandestino and PJ2: some bits of old ground that may enhance current discussion.

Some posts Hazelnuts and a few others made germane to handling and stalling at cruise altitude.

http://www.pprune.org/tech-log/452836-af447-thread-no-3-a-22.html#post6479432

http://www.pprune.org/tech-log/452836-af447-thread-no-3-a-27.html#post6480513

"In level flight at FL350 and M.82 the pitch attitude (=AoA in level flight - HN) was 2.5 degrees".
AoA=4 degrees is approx. the stall warning threshold at M.8 and results in a normal load factor of 1.39.

http://www.pprune.org/tech-log/452836-af447-thread-no-3-a-30.html#post6481326 (This is a table of AoA and time in the event)

jcarlosgon
Recovery was done by pushing forward. ... The surprise was how so long it took.(A comment on control response and time to unstalled a stall jet. )

HN39:
http://www.pprune.org/tech-log/452836-af447-thread-no-3-a-45.html#post6485709
At M=0.8 stall warning is set to occur (see 2nd Interim Report) at approx. AoA=4°, alpha-max = 5°, and the real stall is probably between 6° and 7°.
The second stall warning occurred "around 6°" at M=0.68, where alpha-max=7.3° and stall probably beyond 9°.
An intermittent warning such as may occur due to AoA- and hence g-variations due to turbulence may be considered 'inappropriate' since it doesn't require recovery action from the crew, but that doesn't mean it is false.
It means that the AoA has temporarily exceeded the stall warning threshold.
Mieklour
If I can make a small contribution to this thread.
I have flown the A330 in ALT 2 LAW after a twin ADR incident due to icing conditions.
What surprised me was how "twitchy" the aircraft was, especially in roll.
The handling was much harder than I had experienced in the simulator during training.
We however continued to have valid ADI indications with which to fly attitude + power whilst trying to sort out the very numerous ECAM warnings plus alternating "Stall, stall" + overspeed warnings (spurious of course)
Why the crew should have applied pitch up inputs is a mystery to me unless it was a response to a perceived large overspeed but then why leave the power up?

As mentioned by other posters - the need to manually trim the THS forward is an area that is often seen to be missed by crew undertaking unusual attitude recovery training, especially from very high nose up attitudes and is, in my opinion, one of the few `real gotchas` about the aeroplane.

http://www.pprune.org/tech-log/452836-af447-thread-no-3-a-49.html#post6486989
It certainly was investigated! Aug 1995 and resulted in the fitting of pitot heads with increased heating and a software change to increase the time line before ALT2 was latched. A/P and ATHR initially lost but were restored once out of icing conditions however the lateral twitchy aileron response was very evident for the landing.
http://www.pprune.org/tech-log/452836-af447-thread-no-3-a-52.html#post6487728

Here is the picture that I think will help, courtesy of Hazel Nuts.
https://docs.google.com/leaf?id=0B0CqniOzW0rjOWY3YmIyYjEtOWFhNi00YTEzLWJiNTItOGYyOTU wZTU4MDQz&hl=en_GB&authkey=CILGt_QN

BBF has a chilling summary. It may be hyperbole, given Mieklour's experience with flying it back in Alt 2 latched from cruise altitude. :
Straight and level was beyond them. So used were they to the automatics that the concept of actually flying the aircraft was too much.

Autos- and the way they degrade those hard earned flying skills- are the new killer.

Coagie
25th Aug 2011, 03:03
Dozywannabe,
Not suggesting conspiracy. Just suggesting 3 entities that hoped that each other didn't get too clever or creative, too soon, as long as they all had plausible deniability. "How were we supposed to know the sub didn't know to detect 37.5 khz specifically. After all, a 5th grade science student would have known it"
I agree that malice shouldn't be assumed if stupidity will suffice, but it took France long enough to ask for help.

Chu Chu,
True. Sonar was not optimized for 37.5 khz, but if it were, it's range would have been multiplied tremendously. There's no comparison in sensitivity when tuned specifically to it, rather than listening to a broad dynamic range. Could have used a hetrodyne setup. One of those Albert Michaelson type things.

TheShadow
25th Aug 2011, 03:20
Denouement

As in most such accidents, the final revelations prove to be the disclosure of a previously un-encountered but (in the aftermath) easily explicable phenomenon - and an ensuing chain of complicating and (pilot) confounding circumstances..... some of which are related to design and envelope test-flying deficiencies (but more on that later). Is it a computer-created chain of events? Judge for yourself, from the discussion below, what part the automation (or even weather) played.

After autopilot disconnect due to pitot ice-up and ADR disagree, and some ensuing pilot surprise "disconnect" (from priorities), max power was applied at or near the aircraft's cruise ceiling, the underslung engines provided a pitch-up moment that caused the aircraft to quickly climb into a stall in what's colloquially called "coffin corner". Unfortunately and simultaneously, the autotrim caused the trimmable horizontal stabilizer (THS) to motor (quite unnoticeably) to its maximum "nose-up" sustaining position. This combination of power and "back-trimmed" trim-state created a configuration that was to thereafter (i.e. during their high-rate descent) sustain a deep-stall condition that could only be entered via such a powered speed-to-height "inadvertently zoomed" scenario. Why did they add power? It's a natural pilot response to do something similar when the airspeed winds back off the clock (even though in most such circumstances it only serves to "upset the applecart" of stability).

To explain, the translatable inertia of an aircraft at height has always amazed me. When you zoom climb (even quite shallowly) at very high altitude, you are translating, into a rapidly expiring upwards vector, the very considerable energy that's there solely courtesy of its TAS - (i.e. at cruise height the True Air Speed - i.e the actual speed through the air - is roughly double the indicated airspeed ). When that kinetic energy excess is exhausted (the height increment becoming potential energy), the out of kilter aerodynamics then must dictate what follows. The resulting flight-path down from a stall in that rarefied atmosphere is a "locked-in" function of attitude and power and residual trim-state. The trim state they ended up with was the deadly legacy of the auto-trimming THS rapidly reaching max "nose-up"... as the speed decayed in the thrust-induced zoom. The power of that tilted THS slab was now enough to keep that A330 pitched up into the stall, particularly whilst under engine power. The deep-stall condition is quite a stable flight regime - and that has been known since the first BAC-111 accident almost 50 years ago (only a tail-chute deployment could have saved it). Back prior to automation it was thought to be a phenomenon only associated with T-tailed aircraft (wing-wash swamping the all-flying tail and negating its control). But since AF447 we've discovered that the A330's THS has the power to emulate this lethal configuration... but with deceptively smooth passivity.

Lacking an AoA attention-getting read-out or aural/visual alert, the pilot can only "go for" an ADI pitch attitude (and one that approximates the level flight attitude would seem reasonable to most - and it's what's been generally, but quite mistakenly, advocated here). Unfortunately in a deep-stall condition the relative airflow is not from "ahead" (but from "well below" and ahead), so maintaining (or just abiding) a notional 5 degrees nose-up "cruising" pitch is to fatally elect to live within that deep-stall's boundaries. Deep-stall is a non-alarming condition because of the lack of tail-plane buffeting. In a normal stall the empennage is being "bathed" in wing-created boundary layer separation turbulence - and it's an airframe and control feedback situation that pilots everywhere can recognize as indicative of a stalled condition. Without it you are plummeting down in an eerily smooth and silent (but non-apparent) steep trajectory.

Of course having a stall warning that only momentarily cautions an initial approach to a stall is a design that (for its pilot's alerting function) actually conceals the deep stall. Once embedded in such a stall, the aural alert ceases ("how can I be stalled, there's no stall warning?"). Any stick forward initiative (i.e. angle of attack reduction into the lower AoA numbers) only cooks off (quite perversely) that aural stall warning and increases the perplexed pilot's misunderstanding and non-recognition of his predicament ("now we're stalling with stick forward, how can this be?"). He's never seen this profile on any simulator ride. Even the Airbus test-pilots just "haven't been there" beyond the flight envelope, to test this "post departure" phase. Whatever assumptions about it were ever made? I'd suggest absolutely none. It was an area that, like max achievable Mach and IAS, is best theorized about (only). Much of what is specified for air-testing is about safe boundaries (beyond which there be dragons best left undisturbed). Airbus fails to shine torches (or even look) into dark corners of their beastly envelopes and automation perturbations.

It's no surprise to me that, once locked into their deep-stall smooth-flying regime, the AF447 pilots failed to recognize the nature of their predicament. They momentarily acknowledged their high-rate descent but due their 3-way interaction, their confusion, the smoothness of flight, the silence of low IAS, the distraction of myriad alerts, the darkness of night and lack of any other visual cues, all available cues failed to trigger awareness of any imminent catastrophe. Even the PF's side-stick grip and applied input was concealed from the captain's view. If they'd had a distinctive AoA alarm, experience of it and a laid down memory recall procedure for affirmative action (i.e. positively lower the nose until the stall-approach warning recurs (then ceases) or at least to 20 degrees nose-down), well we'd not now be agonizing over their needless deaths. It's a recognition "consciousness" trigger that's generally lacking here in our automation. As pilots of automated airplanes, we need a climactic bathos (or Eureka moment) whenever we're required to spring into an alert and cognitive state. Other interim pilot-level "fixes" (such as not TOGA'ing the power and prioritizing the lowering of the nose and using manual trim) have already been addressed in Airbus pilot bulletins.

I'd be interested in any rebuttals..... technical or otherwise. Do I think that any fixes implemented will be effective? Partially but not wholly is my suspicion. No Airbus or Air France or BEA bod is going to want to acknowledge the totality of the AF447 conundrum. AF447 will reside in the Pilot Error Hall of Infamy forever. But to allow this, without demur, would be a calumny against the profession of the professional aviator. And that's why I'm penning this. Put this out for the public and journalists to see and understand. That's how you might avert the way I see the final report going.

jcjeant
25th Aug 2011, 03:24
Hi,

DW
All I intend to illustrate with this is that neither military operations nor deep-ocean exploration are immune from mistakes, and before throwing accusations of conspiracy aroundIt does not imply any conspiracy .. this is simply to show that some people of BEA and other bodies (in good faith ?) lacked common sense and also remained deaf to certain warnings from other experts (as some has think about 447 pilots who remain deaf at the stall warning)
The results of this lack of good sens are not meaningless when you know the money trowed in and the delay for the families and also the delay for any recommendations to be issued ...
If you find that your house keys are no longer in your pocket .. will you start to look in your attic (where you go 3 times a year and last visit was a month ago) or are you going to start looking in the room you are in most cases.
And if it's dark .. do not you turn all the lights to help you see them?

Lyman
25th Aug 2011, 03:26
Coagie. Coagie. The THS was effectively dormant for the climb. The PF accomplished the climb in ordinary and unassisted ways? He also attempted to stop it. The THS enters, stage left, basically at STALL...

Coagie
25th Aug 2011, 03:27
The PF pulled back on the stick for a long while, causing the trim to increase so much. It wasn't just the extra thrust from the underslung engines causing the sudden climb.

deSitter
25th Aug 2011, 04:11
Can we start a thread on how these guys could have recovered? What immediately occurred to me was to generate asymmetrical thrust to perhaps roll over, or at least enough to get into a steep bank that would lead to a nose-dive. Once the nose was really down the problem would be solved. You would need to physically understand throttle response to time things.

Clandestino
25th Aug 2011, 07:22
Can we start a thread on how these guys could have recovered?Eeeerm.... by pushing the stick forward?

Ladies and gentlemen, did it ever occur to you that the lift equation, Cl vs Cd curve, power required vs. power available et al. are not just some scribbling on paper or PDF that are to be learned by rote to pass the ATPL exams but extremely accurate descriptions of principles that keep us flying?

I am going on my silly sailing vacation, since I don't fly DC-4 but Q400, it will be four days instead of three weeks. I wonder what you'll make out of this thread by then.

Lonewolf_50
25th Aug 2011, 11:59
I am going on my silly sailing vacation, since I don't fly DC-4 but Q400, it will be four days instead of three weeks. I wonder what you'll make out of this thread by then.
Hash?

Fair winds and following seas, Clandestino, hope the time at sea is a joy. :ok:

(Also, suggest you avoid Eastern Seaboard of the US, seems that Irene has arrived and is blowing hard).

iceman50
25th Aug 2011, 12:19
TheShadow

Not quite sure what you are trying to say in your post but there are so many inaccuracies in it that it was not worth the time reading it!

The discussion around CLB thrust and 5 degrees is more to do with the climb phase up to CRZ level. Below 10000' it is 10 degrees. Cruise level the attitude it is around 2.5 degrees, the NORMAL cruise attitude so there is NO need to go to 5 degrees, any thinking competent pilot should be able to work that out, otherwise they should not be in the flight deck.

When the A/THR disconnects it goes to THR LOCK and keeps the thrust set at the time until the pilot moves the thrust levers, so no great dramatic thrust pitch up is induced. The autotrim will only work to compensate for PILOT input and it went up due to pilot demand!

deSitter

There is No need to start a thread all they had to do was get the nose down. If they had held the input the nose would have gone down and the autotrim would have then assisted with a sustained nose down input. They could even have helped by using manual nose trim themselves[/COLOR], as taught in UA recoveries. As for trying to roll / yaw the nose down.:ugh::ugh:

Lonewolf

If you can explain to me, in plain language, why a stall warning system goes dormant while the aircraft is stalled, in flight, and tell me why this is allegedlyl a good design, I'd sure like to hear it.

It only went dormant <60kts IAS, what manufacturer / regulator would think that a properly trained Airline Pilot would get a Transport Category A/C into a deep stall at less than 60kts!!! Having ignored the warning for >50 seconds prior to that.

Lonewolf_50
25th Aug 2011, 12:39
iceman, you didn't answer the question. ;) I understand how it happened. Given that a pitot static system can fail and give erroneous inputs (they can, this has been known for a long time) I was asking for a defense of the design decision, considering that a number of aircraft features are routed through a weight on wheels switch ... there may be a solid answer, but I've yet to see one.

AlphaZuluRomeo
25th Aug 2011, 12:40
Hi
Procedure that required setting 5°/CLB by heart was in force at the time of the accident. Page 59 of interim 3 report in English refers.
That procedure seems to have been badly phrased, as there are so many questions about it.
Anyway, I think the way its writer intended it, it was :
- if there is a danger for the flight safety => apply memory items (which is as you quoted is, 5°/CLB), then refer to QRH for the "fine tuned" attitude/thrust to apply, then manage the failure.
- if there is no danger => refer to QRH, no immediate action (i.e. implicitly, fly ahead until you know which pitch & thrust to apply), then apply it, then manage the failure.

In AF447's case, there was IMO no danger. This would explain why, as soon as june 2009, AF published a note "reminding" to its crews that they were not to apply the memory items in high altitude cruise.

For the rest (i.e. is or isn't 5°/CLB "dangerous" and/or will it or not trigger the stall warning in HA cruise), I have no clue and won't comment.

HazelNuts39
25th Aug 2011, 14:50
Doesn't it bother you that you got a stall warning for no good reason by keeping the nose up in a pitch climb for no good reason?For no good reason? Two apparently very brief occurences of stall warning were observed at 02:10:10 and 02:10:13 (page 29 of BEA#3). The reason for those is clearly shown in the traces for normal acceleration on page 42 (Note that normal acceleration is proportional to AoA at a given airspeed). The purple line is the DFDR recording, the blue line is what Airbus has calculated for the pilot's control input without turbulence. At 02:10:10 the pilot pulled slightly over 1.3 g, and a gust increased that to slightly over 1.6 g. Similarly at 02:10:13 the pilot was pulling 1.4 g (increasing towards 1.5 g at 02:10:15), and again a gust increased the pilot commanded 'gee', this time to less than 1.6 g. I would expect the pilot to recognize the 'gusty' origin of the brief warnings, and he should have done nothing except maintain pitch attitude. Whether that is 2.5 or 5 degrees is really of secondary importance.

Welsh Wingman
25th Aug 2011, 15:01
At least until we have received the final and more comprehensive BEA report in 2012, could we please not get sidetracked on Boeing v Airbus ideological debates?

The main aviation safety issue in recent years has been loss of control, with the main focus in relation to automation and the "human interface" (specifically concerns over training and the absence of line manual flying), and across all aircraft manufacturers. Even to a Boeing veteran like myself, there are only two "Airbus specific side issues" that this thread has thrown-up and neither should have resulted in themselves in the downing of AF447.

(1) The historic role of Airbus in creating the impression to line management that "planes fly themselves", even if partly inadvertently, and the knock-on effect upon the training culture.
(2) Several additional "complications" in an Airbus cockpit when things go awry, if cockpit discipline is not tight i.e. feedback issues (e.g. SS v control column, and the throttle and trimming) and the PNF is visually less aware of how the PF is by-hand flying. I suppose you could add under this heading the <60knt stall warning design "issue".

This is a training/human behaviour issue otherwise the temporary UAS on AF447 would have been temporary by-hand P+P flight and another logbook entry on the Thales pitot tubes being phased out......

stepwilk
25th Aug 2011, 16:03
aircraft manufacturers have been claiming the ability of their aircraft to "fly themselves" to some degree ever since the introduction of INS-enabled autopilots

Not quite the same thing, but remember Cessna's "Drive it up, drive it back down" advertising campaign of the 1950/'60s?

DozyWannabe
25th Aug 2011, 16:07
(1) The historic role of Airbus in creating the impression to line management that "planes fly themselves", even if partly inadvertently, and the knock-on effect upon the training culture.

Well, let's be fair here - if they'd asked the engineers rather than the sales guys they would have got a more honest answer going all the way back to 1988. As a slightly tangential aside, aircraft manufacturers have been claiming the ability of their aircraft to "fly themselves" to some degree ever since the introduction of INS-enabled autopilots - in fact the first time I ever heard the term used (albeit in a fictional setting) was as an annoying kid watching the annoying kid in "Airport 1975" saying the very same thing about the 747. I'm sure the Boeing sales team would not have gone out of their way to qualify that remark. And the movie, though utterly terrible in any kind of objective sense, certainly demonstrated via some rather nifty stunt flying that the 747 was very stable in environments where it would never normally be used.

Another quasi-fictional allusion to said ability crops up in John G. Fuller's "Flight 401" book, this time in reference to the L-1011 - and no matter what you think about the supernatural bobbins included therein, he did his research on aircraft and line operations pretty well.


(2) Several additional "complications" in an Airbus cockpit when things go awry, if cockpit discipline is not tight i.e. feedback issues (e.g. SS v control column, and the throttle and trimming) and the PNF is visually less aware of how the PF is by-hand flying.

Not completely unaware, mind... PJ2 confirmed a few posts back that most of the FBW Airbus pilots he knew didn't really see the feedback thing as an issue.

My interpretation of the CVR, for what that's worth, is that the PNF saw what the PF was doing by watching the attitude of the aircraft on the ADI, but for reasons that are likely to be endlessly debated in human factors forums for years, he either failed to accept that the guy to his right really was mashing the controls about that cack-handledly* (would you, or any pilot on here for that matter not have a moment of "this can't be happening"?), or indeed came to that conclusion but again, for reasons that will be debated for years, felt he didn't have the authority to tell his colleague to get his hands off the d*mn stick right now. We've seen instances of this before, with KLM4805 at Tenerife and Birgenair - but previous instances have tended to involve an F/O who felt he couldn't overrule his Captain. With a poorly-defined command gradient, is it possible that an F/O can also feel he or she does not have the right to give orders to a colleague of the same rank?

Also, I don't think flight deck discipline and airmanship in general can be completely separated - if you don't maintain proper CRM and organise your flight crew effectively then you're probably going to end up in the cacky eventually no matter what aircraft you fly.

I suppose you could add under this heading the <60knt stall warning design "issue".

Fair comment, but as of now we don't know how many other types also have the same issue or similar. I'd be prepared to bet money that it's more than a few... One of the perennial issues that has dogged stall warning technology in jetliners since the days of the Comet, Caravelle, 707 and DC-8 is the number of hull-losses attributed to the crew incorrectly diagnosing a stall warning as false when it turned out not to be. I find it hard to fault any manufacturer making a design assumption like that because this is the first time in decades that an airliner has ended up so far outside of it's design parameters.

This is a training/human behaviour issue otherwise the temporary UAS on AF447 would have been temporary by-hand P+P flight and another logbook entry on the Thales pitot tubes being phased out......

Absolutely agree. Though having said that it offers intriguing technical questions about all modern fourth-generation airliners - and I wonder if Airbus and Boeing will be willing to examine their designs to see what potential gotchas lurk when the aircraft is taken that far outside of it's envelope.

* - I happen to be cack-handed/southpaw/lefty, so I can use that phrase. ;)

BOAC
25th Aug 2011, 16:22
Welsh - a good summary, I would, however, make the stall warning item the third type-related issue, and really what other types/manufacturers 'do' or 'did' is not relevant to this occurrence.

As others have said, 2.5 deg/5 deg.emergency/non-emergency - no matter, none would have caused this crash, but 11deg did initiate it. There are enormous holes in the 'French' cheese in this accident, and Dozy sums up the HF neatly in his middle para. I am still greatly puzzled by the lack of assertiveness of PNF.

Lots of new cars for the lawyers.

PJ2
25th Aug 2011, 16:29
HN39;
Whether that is 2.5 or 5 degrees is really of secondary importance.
BOAC;
As others have said, 2.5 deg/5 deg.emergency/non-emergency - no matter, none would have caused this crash, but 11deg did initiate it.
I agree with both these statements.

Welsh Wingman
25th Aug 2011, 17:15
(1) To be fair, I have added "inadvertently" to point the "blame" in the sales direction. I am acutely aware that Airbus's head of training had a battle just to keep training at pre-existing levels (discussed previously by PJ2, on the main AF447 threads), when heavy automation is basically "existing airmanship plus".

(2) I was intrigued by PJ2's comment on this aspect, as he is an AB veteran. Takata has set out the AF command structure in place at the time of this incident and facing the CDB, which was not ideal for any "unhappy" PNF in the LHS without the "unsatisfactory" handover on AF447. Would the PNF have been more assertive if he could have seen what the PF was specifically doing through a clearly visible RHS control column (or at least if the LHS SS was moving in tandem with the RHS SS movements commanded by the PF?)? The throttle moving also? Would the PNF at least have been better placed to properly brief the returning CDB? Might this have overcome CRM shortcomings and saved the day?

(3) "Design assumptions" are always dangerous. The Titanic was "unsinkable" because how could White Star possibly flood the first five watertight compartments.....? What floats, can sink. What flies, can stall. A stall warning really should stay on until an aircraft is no longer stalled. The stall warning ceasing just after the CDB returned to the cockpit was, at best, "particularly unhelpful".

(4) We Brits naturally prefer "evolutionary", which is why I value PJ2's viewpoints on the more "revolutionary" aspects of the AB design philosophy. From Stony Point through Aeroperu and Birgenair to Colganair, there are stall warning issues and pilots forgetting their training and grimly pulling back on their control columns. Post-Stony Point, was the industry ready for another system? AF447, and the ignored stall warnings, tend to suggest not I would submit. Hopefully, with control column pilots now acutely aware of the "stick shaker" issues after numerous hull losses, there won't be a SS repetition.

As I said, I don't want to get dragged into any AB particular issues.

This is an across the board training issue. The less routine manual flying that pilots do on any aircraft (within the flight envelope), the harder it is for them to suddenly "ride to the rescue" in a degraded flight envelope emergency. That must be self-evident........

Lyman
25th Aug 2011, 18:21
apropos not much,; had the crew recovered, the landing back at CDG would have been interesting, especially in a crosswind.

DozyWannabe
25th Aug 2011, 19:28
(1) To be fair, I have added "inadvertently" to point the "blame" in the sales direction.

I know, just thought I'd reinforce it for the benefit of non-native English speakers who may not pick up the inference as easily as I did. :)

(2)...Would the PNF have been more assertive if he could have seen what the PF was specifically doing through a clearly visible RHS control column (or at least if the LHS SS was moving in tandem with the RHS SS movements commanded by the PF?)? The throttle moving also? Would the PNF at least have been better placed to properly brief the returning CDB? Might this have overcome CRM shortcomings and saved the day?

Well, that's a difficult question - and as I said, one that the human factors bods will be debating back-and-forth till kingdom come. Common sense suggests that it might have made a difference, but on the other hand there's the CVR that suggests that the PNF might have been aware that his colleague was overcontrolling even without feedback, as well as the historical cases (Birgenair, NWA) where the PNF in both cases had the yoke in front of them reflecting the PF's inputs, and still failed to put two and two together.

(3) "Design assumptions" are always dangerous. The Titanic was "unsinkable" because how could White Star possibly flood the first five watertight compartments.....? What floats, can sink. What flies, can stall. A stall warning really should stay on until an aircraft is no longer stalled. The stall warning ceasing just after the CDB returned to the cockpit was, at best, "particularly unhelpful".

Of course they are, but as I'm sure you're aware, design and engineering are and have always been underpinned by the art of compromise. In this case (as I said above) there was a history of incidents where the number of false stick-shaker events led to an assumption on the pilots' grapevine that most stick-shaker events were false, with fatal consequences when a real stick-shaker event happened. Manufacturers were then faced with the task of weeding out the circumstances in which the stick-shaker was a false alarm, and Airbus's logic was based on a set of parameters that were so outside the flight envelope that they couldn't see it happening with the aircraft aloft - it's possible other manufacturers have done the same and at the risk of repeating myself I hope they all band together to find out.

The Titanic (another minor obsession of mine as it happens) and the Comet 1 were both examples of designers working at the limits of contemporary knowledge (regarding worst-case maritime collision scenarios in the former and metal fatigue in the latter). Now we know that it is possible to stall a modern airliner to such a degree that it intersects the stall inhibition parameters, it's likely that designs are going to have to change.

(4) We Brits naturally prefer "evolutionary", which is why I value PJ2's viewpoints on the more "revolutionary" aspects of the AB design philosophy.

Now my old Prof considered the A320 more "evolutionary" than "revolutionary" once he got to poke around inside, the only difference being that the aircraft it evolved from (the A300/A310) was already probably the most technologically advanced airliner flying up until that point (though again, as I said before, the L-1011 came close). It depends on how you look at it - most of the circumstances that made two large, connected central control columns necessary in the first place (largely to do with leverage when the flight surfaces were directly connected by cable) were no longer applicable by 1972, let alone 1982 when the A320 was being specified.

From Stony Point through Aeroperu and Birgenair to Colganair, there are stall warning issues and pilots forgetting their training and grimly pulling back on their control columns.

Aeroperu was slightly different - loss of pitot data affects airspeed indications, and as long as you click the A/P off, it's relatively straightforward to manage. Aeroperu had the static ports taped over, which was a whole other ballgame in terms of what it did to the instruments.

Hopefully, with control column pilots now acutely aware of the "stick shaker" issues after numerous hull losses, there won't be a SS repetition.

Fingers crossed!

This is an across the board training issue. The less routine manual flying that pilots do on any aircraft (within the flight envelope), the harder it is for them to suddenly "ride to the rescue" in a degraded flight envelope emergency. That must be self-evident........

Absolutely - but the pressure must be brought to bear on the airlines, specifically management, that the status quo is not on, and again - as I've said before - who will be the first to stick their head above the parapet?

TJHarwood
25th Aug 2011, 19:30
Given that he was CATOBAR trained on the BBS1 and the BBS2 for the old Ark and Eagle, I suspect the Wingman has very decided views on the AoA going to 0 and ceasing the stall alarm at less than 60 knts and is showing remarkable restraint in keeping his views to himself......

airtren
25th Aug 2011, 19:31
Iceman50,

Trying to get the ND, is only the beginning of the first part of a Stall Recovery.

There is more to Stall Recovery than that, and I read "deSitter's" post, as a suggestion on discussing all parts or aspects, and as far as I am concerned that seems to be an interesting idea.

....
deSitter

There is No need to start a thread all they had to do was get the nose down. If they had held the input the nose would have gone down and the autotrim would have then assisted with a sustained nose down input. They could even have helped by using manual nose trim themselves[/COLOR], as taught in UA recoveries. As for trying to roll / yaw the nose down

Welsh Wingman
25th Aug 2011, 19:40
TJHarwood

No comment!

airtren

Best to leave a stall recovery thread until after the final report. Besides, in the meantime, best to stick to and focus in on what went wrong after the temporary UAS leading to A/P and A/T disengagement and before things really went pear shaped and "real airmanship" was required at FLT -100 per min.

TJHarwood
25th Aug 2011, 20:26
I think the Wingman was referring to "revolutionary" in the narrow context of the control columns, as the SSs would have been revolutionary to any pilot (even an A300 pilot) entering the flight deck of a new A320! As Boeing are still using control columns in the 21st century, even on FBW aircraft such as the B777, might it be to reflect pilot mindsets......?

With the benefit of hindsight, would it have been better for all manufacturers to use the same control column system whilst jointly addressing the Stony Point "stick shaker"/stall issues? We now have nearly half the industry using a different system, with flaws appearing.

AF447 stands out. The loss of Capt Warner was a test flight, with all that entails, and no more indicates an A330 fault than the RR engines FOHE issues indicates a B777 fault. The Air Afrique A330 loss is the least of Libya's priorities, so no satisfactory investigation is assured.

AF447 is critical so, unless pilots are better trained at high altitude manual flight, and with all the additional cost that entails, the pitot tubes and ADIRUs had better be damn reliable!

Welsh Wingman
25th Aug 2011, 21:01
Thanks for your comments. A few points:

(1) Definitely one for the human factors experts, but unlikely PNF grasped just how far back/NU the PF's inputs were. Not relevant if CRM is perfect, but there already seems on these threads to be a certain amount of consensus on CRM shortcomings to a differing degree....

(2) As TJHarwood has alluded to, and as someone who "lived" during my early piloting years by my AoA indicator, best not to get me started on the design philosophy that resulted in a stall alarm being repeatedly switched off when the aircraft remained ......... in a stall (however far outside of the designed flight envelope).

(3) I wasn't thinking in terms of the A300, although there were revolutionary aspects, but more in the context of what Lockheed, Boeing and McDonnell Douglas were producing. A different "philosophy".

(4) In this world of aviation deregulation, more than ever, there needs to be a global (i.e. especially USA/EU) regulatory response. No airline will take an expensive lead. AF, for example, had 3 hull losses (2 with heavy fatalities) in a decade, but retains a loyal customer base. It has got to be extreme for an (insured) airline before corporate reputation dictates huge costs on a root and branch training and manual flight expertise revamp.....

Additional costs will have to come down as a level playing field, or it is just about hopeless.

DozyWannabe
25th Aug 2011, 21:08
As Boeing are still using control columns in the 21st century, even on FBW aircraft such as the B777, might it be to reflect pilot mindsets......?

I'm sure I read on here earlier that the original B777 design used sidesticks, but the launch customer's (UA) pilot's union objected - certainly not representative of pilots as a whole!

With the benefit of hindsight, would it have been better for all manufacturers to use the same control column system whilst jointly addressing the Stony Point "stick shaker"/stall issues? We now have nearly half the industry using a different system, with flaws appearing.

The most interesting link posted on these threads (more than once)
was the Nasa study of A vs B control systems for CFIT escape. Covering sidestick, laws protections the lot. Result:


the pilots overwhelmingly thought B was the better system
the actual outcome was that the A system saved your ass more often

So which set of designers got it right ? Not easy.

Sums it up for me.

AF447 is critical so, unless pilots are better trained at high altitude manual flight, and with all the additional cost that entails, the pitot tubes and ADIRUs had better be damn reliable!

Colour me cynical, but I'd be surprised if most airlines couldn't purchase a small airfield hangar and a bunch of trainers (jet and prop) for a fraction of the CEO's annual bonus!

Anyways, I'm spent for now - later.

Welsh Wingman
25th Aug 2011, 21:26
Touch wood, but CFIT is not the killer it once was (if still too frequent).

LOC has been the real concern in recent years.......

Lyman
26th Aug 2011, 01:02
And one very good reason is the 320/family CFIT escape solution. I am a big fan!

Jazz Hands
26th Aug 2011, 07:53
This quote from Joe Sutter popped up on a blog yesterday (http://karlenepetitt.********.com/2011/08/william-e-boeing-jr.html):

Airplanes are supposed to do what the pilot tells them not the other way around. The difference between Boeing and Airbus is the Airbus tells the pilot what to do. That's wrong! The pilot should tell the plane what to do. And you can tell those Airbus people I said that. What are they going to do to me anyway? I'm ninety years old.

AlphaZuluRomeo
26th Aug 2011, 09:32
@ Jazz Hands:

1/ Your link appears broken. Too many stars, it seems ;)

2/ I'll ask his messenger, as Mr Joe Sutter seems out of reach:
- Where exactly did the Airbus A330 of AF447 tell the pilot what to do?
- Where exactly the Airbus A330 of AF447 did not do what its pilot asked for?

DozyWannabe
26th Aug 2011, 12:04
@Jazz Hands, AZR,

Joe Sutter is enough of a legend that he's perfectly entitled to his opinion, even if it betrays his misunderstanding of how a competitor's product works. Hell, if I made it to 90 I'd be inclined to be as opinionated as I liked whenever I liked, even if I knew I was talking horlicks!

Lyman
26th Aug 2011, 13:24
The stuff of urban legend.....

One goal of urban legends is to entertain, and the other is to distract. Comedy has to be generic, or not enough people 'get' it.

So from an internet comet comes further misunderstanding. "Tell the PILOT what to do?" Well, Yeah. By doing it without him/her noticed, warned; by stealth/surprise (ready for flash bang, here)

Bottom line is this, probably. As the a/c "gives it back" it "hangs on". It is not a "secret", for it is published and trained. It is counter intuitive, however, and ultimately leads to disaster, along with other "eccentrics".

POV? Yep. Maybe PJ2 was right, Maybe "Human Factors" is the landscape for the discussion. Although the problem ultimately, is a design that requires a degradation of human skills, and a deeper reliance on Technology that to some extent doesn't allow for an everpresent design consideration. BTW, This "Technology" was new when I was using an APPLE e2.

ROTE learning ending up requiring ROTE handling. There was a fourth "pilot" aboard, and we neglect that influence at our great risk.

Some "one" decided Autotrim was an excellent fallback in recovery from Unusual Attitude(s), and that STALL warning could (should) be defeated at low (!) speed. PILOT ERROR I'm saying, ennabled by a remote command from another time, and another place. What a deadly Intrusion!

So, Yeah. Next time, can we have APPLE?

TJHarwood
26th Aug 2011, 15:09
AZR

"Where exactly did the Airbus A330 of AF447 tell the pilot what to do?"

As BOAC, Lyman and Wingman have alluded to, and wp no doubt to your primary contention that the pilots weren't listening to the A330 telling them that it was stalled(!), the A330 repeatedly told the pilots it was no longer stalled (and at a critical point for stall recovery at FLT 350 as the CDB re-entered the cockpit).........

Lyman

"Although the problem ultimately, is a design that requires a degradation of human skills"

I think that is going a little far, even if there is considerable concern expressed as to what has happened in practice over the past 30 years. There is nothing in the underlying design philosophy itself to preclude pilots from honing their flying skills on light aircraft, line flying by-hand within the flight protection envelope or spending additional time in the simulator. I liked the Wingman's description of Airbus (and the B777 and B787, hence not Boeing v Airbus?) as "airmanship plus", of which the late great David Davies (his fellow countryman) let alone Gordon Corps would approve, which conveys the need for standard flying skills plus additional skills. The problem is far far wider than Toulouse......

PJ2 - any thoughts?

infrequentflyer789
26th Aug 2011, 17:03
@ Jazz Hands:

1/ Your link appears broken. Too many stars, it seems ;)

2/ I'll ask his messenger, as Mr Joe Sutter seems out of reach:
- Where exactly did the Airbus A330 of AF447 tell the pilot what to do?
- Where exactly the Airbus A330 of AF447 did not do what its pilot asked for?

I'll bite:

a) I don't think they turned FD off did they ? Maybe it told them to climb ?

b) [easier] The pilot definitely, forcefully and persistently told the a/c to climb, meanwhile the stupid a/c ignored him and continued to fall out of the sky. Presumably if you tell a Boeing to climb out of a stall, it does just that.

Did I win ? :E

TJHarwood
26th Aug 2011, 17:33
Three A320 hull losses between 1988 and 1992, essentially because the flight crew and the aircraft were on a different "wavelength" i.e. unfamiliarity issues.

Notice any similarities between the Air Inter flight crew's discomfort with having to suddenly make a non-precision landing at Strasbourg and the AF447 F/Os discomfort at having to take manual control at FLT350 (no visual aid, not even moonlight)?

AF447 is so depressing because it is 17 years later, and we have another total disconnect between a flight crew and their aircraft.

Simulator (AB speak) - learn to fly (typerating) direct law, progress to alternate law, round-off with normal law? Gate to gate, every time. All sides of the industry implicated, not just manufacturers or a specific manufacturer (SS/feedback issues notwithstanding vis-a-vis AB).

Commercial pressures? Non fici facio, vera prae ceteris - as Davies would say. Get it sorted. Thanks to automation, properly used, there has never been so little excuse for an air crash.....

lomapaseo
26th Aug 2011, 19:11
Three A320 hull losses between 1988 and 1992, essentially because the flight crew and the aircraft were on a different "wavelength" i.e. unfamiliarity issues

Reminds me of planning a driving vacation in the UK where I would have to adapt to driving with the gear shift on my left and round-abouts that go the wrong way for my skill base..

Do I adapt ?

Take my chances at a higher accident rate while learning to adapt

call for a change of driving regs and car design in the UK?

or simply stick to driving only familar cars?

DozyWannabe
26th Aug 2011, 19:32
Three A320 hull losses between 1988 and 1992, essentially because the flight crew and the aircraft were on a different "wavelength" i.e. unfamiliarity issues.

And Airbus changed their training and the FMC interface accordingly.

Notice any similarities between the Air Inter flight crew's discomfort with having to suddenly make a non-precision landing at Strasbourg and the AF447 F/Os discomfort at having to take manual control at FLT350 (no visual aid, not even moonlight)?

Not really - for a start the AF447 PF doesn't make any reference to discomfort until the roll oscillations start - there's no evidence that he's aware he's doing the wrong thing.

Secondly, while the main technical revision to come from the Strasbourg crash was making the Honeywell FMC display the difference between V/S and FPA select in a more obvious way (by the simple addition of illuminating two zeros to the right of the indicator in V/S mode), the background of the two incidents couldn't be any more different, particularly with regard to human factors. Air Inter dealt exclusively in very short flights with very quick turnarounds - very different to Air France's long-haul operations where the possibility of making up lost time is much easier. This is important because Air Inter in the '80s was placed in direct competition with SNCF's new TGV rail service and therefore the penalties for not making schedule were potentially severe.

In the case of the Strasbourg accident, both the Captain and F/O were experienced pilots, but both had less than 100 hours on the A320 - something which would not be allowed today. When Approach control told the Air Inter Captain that he could not use his preferred approach and would have to land on the reciprocal runway, the report says that his tone of voice on the CVR becomes increasingly agitated, possibly due to a combination of frustration at not making schedule and uneasiness with the fact he'd be making an NPA at night for the first time on this type.

Then we have the fact that ATC gave the crew an incorrect vector, putting them off-course laterally, the aforementioned bad interface design making it possible for them to set a 3300 ft/min descent rate as opposed to a FPA of 3.3 degrees and for the worst bit of luck, a random pocket of turbulence causing the A320 to descend even more rapidly.

What this adds up to was that the situation in the flight deck was tense, but they weren't aware of how severe their situation was until they were a few feet away from the mountain. Compare this to the AF447 case where they were well aware they had problems almost as soon as the PF began overcontrolling, but they did not or could not formulate or action a plan to correctly resolve the situation.

The other big difference is the fact that the Strasbourg A320 was in autoflight almost all the way down to the ground, whereas all evidence indicates that the AF447 A330 was manually controlled into trouble.

AF447 is so depressing because it is 17 years later, and we have another total disconnect between a flight crew and their aircraft.

I'd argue that the more pressing worry in the case of AF447 is the flight crew's disconnect from *each other*. They could see what the aircraft was doing and so unlike the Strasbourg crew they were not "behind the aircraft" as such except for one critical detail, and that was that the aircraft was stalled.

the A330 repeatedly told the pilots it was no longer stalled (and at a critical point for stall recovery at FLT 350 as the CDB re-entered the cockpit)

To be fair to the aircraft, it did tell them it was approaching stall, and then that it was stalled, for nearly a minute before the readings caused the stall warning to trip out. Why did they not respond accordingly, whether the Captain was there or not? Why did neither of the F/O's mention to the Captain that they'd had a minute of stall warning prior to his arrival?

I'm not saying that the stall warning logic doesn't need an overhaul, because it clearly does, but ultimately the warning was there and continued long enough for someone to take notice and do something about it (to say nothing of the oscillating bank angle, rollercoaster pitch changes and the rapidly unwinding altimeter)?

Commercial pressures? Non fici facio, vera prae ceteris - as Davies would say. Get it sorted. Thanks to automation, properly used, there has never been so little excuse for an air crash.....

Emphasis mine, and therein lies the rub!

[ Addition : Air Inter's usual practice, because of the unique way they used their aircraft, was to frequently bat their Caravelles around at 300KIAS+ below 10,000ft (sometimes considerably below!), which tended to play havoc with the GPWS hardware available at the time, and for this reason they received a special dispensation to not have GPWS fitted to their A320s, despite incoming regulations requiring it. Shortly after the accident, GPWS became mandatory and was retrofitted to their fleet. ]

Welsh Wingman
26th Aug 2011, 19:56
Re: incremental change.

Weight dictated FBW on any SST, with the Concorde's famous rams's horn control columns and "feedback". Built by the predecessors of Airbus.

CONCORDE SST : FLIGHT SYSTEMS (http://www.concordesst.com/flightsys.html)

Love the analogy (don't you realise we mainly build roundabouts to stress American tourists, particularly if they are not from Utah....?!) Do Ford/Chrysler/General Motors, when they sell cars in the UK, either:

(1) move the steering wheel to the right of the gear shift; or

(2) abolish the steering wheel in favour of side sticks without (artificial) feedback?

Incremental, even when it involves a bit of a leap....

The serious point, when Airbus embraced automation ahead of Boeing (not instead of Boeing - see B777 onwards), is that there were various options.

Some fast jet pilots were familiar with sticks (side or otherwise). Most civil airline pilots were not.

SSs and the absence of "feedback" were not critical to the automation drive, and don't let anyone tell you otherwise - see Concorde/A300. It was a decision on one aspect of automation.

Lyman
26th Aug 2011, 20:17
Captain Harwood,

The degradation of skills I see is not limited to direct neglect, nor would it be. A "Thick through Disuse" type thing, to where the skills are vestigial, if any remain at all. A great deal of hype re: the platform, at the expense of Laissez faire, le Pilotage?

Now that would be acceptable, should the numbers firm up a sound reason for allowing skills to atrophy. There are none, as you aptly show, 447 is a sad example of a precious penalty for allowing a "blind spot"?

One small addition, the market will not support levels of auto didactic skill, the investment will be ignored, and the entry level, de minimus, will prevail. Thus it actually is a direct degradation, though in this case, market driven.

There is one additional disincentive to "hiring" the self taught (self invested) man/woman: "That one Clive, looks like a troublemaker, to me!"

:ok:

DozyWannabe
26th Aug 2011, 20:20
@Welsh Wingman - I think a more appropriate analogy would be :

"When we went from horse-drawn carts to motor vehicles, did we attach ropes to the front axles and steer with that (because after all, that's what people are used to), or did we design something more appropriate for the technology?"

and later

"When we went from gigantic steering wheels required for the leverage to move worm-gears, via rack and pinion, to power steering, did we keep the wheels artificially large (because, after all, that's what people were used to), or did we design something more appropriate for the technology?"

If we're to believe the earlier poster, Boeing only retained the yoke under pressure from a single pilot's union (the one that belonged to their launch customer). There has been no unequivocal evidence that the SS/feedback issue has ever played a role in any recent LOC incident (not least because several of them involved yoke-equipped airliners). This argument feels like a cul-de-sac to me, and I think it's a shame we're having it again.

[PS. WW - I'm sure you know which type the sidestick concept was originally tested on, right? ]

Welsh Wingman
26th Aug 2011, 20:28
I don't wish to be accused of putting words into TJHarwood's mouth, but I interpreted his comparison between the crashes as limited to the similarities between the instant discomfort of the PF upon losing his automation. I don't think that was a happy cockpit from the A/P disconnect, and the roll oscillations weren't long in coming....

DozyWannabe - but you raise a point that TJHarwood appears to have overlooked i.e. PNF "nagging". Wasn't the PNF in 1992 concerned about the PF's positional shortcomings (sadly horizontal, not vertical) in much the same way as the AF447 PNF was concerned about the PF's inputs and the climb? Good point re: disconnect between pilots on both occasions.

And whatever one think about an AoA indicator or BUSS as an option, I think we can all agree that a GPWS should never be optional (whatever SNCF's TGV competition).

Human factors, and that must focus on the interface and training. Automation, properly used i.e. "airmanship plus".

ChristiaanJ
26th Aug 2011, 20:45
PS. WW - I'm sure you know which type the sidestick concept was originally tested on, right? ]The exact answer to that quiz question is of course "F-WTSB".
Without asking Google, I'm not sure whether the original 'joystick' idea dates back to the Viper (F-16) or to the early Atari video game consoles...... i.e., what inspired what?

flydive1
26th Aug 2011, 20:49
The wright flyer used a side stick;)

ChristiaanJ
26th Aug 2011, 20:55
The wright flyer used a side stick;)Thanks, nice one!

DozyWannabe
26th Aug 2011, 20:58
...I interpreted his comparison between the crashes as limited to the similarities between the instant discomfort of the PF upon losing his automation. I don't think that was a happy cockpit from the A/P disconnect, and the roll oscillations weren't long in coming....

The Air Inter captain never entirely lost his automation, just his pre-programmed approach. He never got as far as having to manually control the aircraft, instead following the radar vectors and initiating descent via FMC input.

DozyWannabe - but you raise a point that TJHarwood appears to have overlooked i.e. PNF "nagging". Wasn't the PNF in 1992 concerned about the PF's positional shortcomings (sadly horizontal, not vertical) in much the same way as the AF447 PNF was concerned about the PF's inputs and the climb? Good point re: disconnect between pilots on both occasions.

Thanks! So - if I recall correctly - yes, the Captain started to say something to the effect of the altitude or V/S not looking right, and in an unfortunate coincidence, at the exact same time the F/O interjected to point out that the display had them to the left of the airfield (which was due to ATC turning them onto final prematurely), which then preoccupied both pilots (in much the same way that an unfortunately-timed radio transmission distracted the Kegworth Captain as he began to re-evaluate the symptoms).

And whatever one think about an AoA indicator or BUSS as an option, I think we can all agree that a GPWS should never be optional (whatever SNCF's TGV competition).

Of course, with 20/20 hindsight!

Human factors, and that must focus on the interface and training. Automation, properly used i.e. "airmanship plus".

No argument from me there!

@CJ : I think the first modern sidestick came with the Mercury project at NASA. :)

Welsh Wingman
26th Aug 2011, 21:02
I haven't been following this thread from the beginning, so not sure from where the "story" emerged that B777 yokes was purely down to United line pilots. It most decidedly did not, and there was widespread consultation with Boeing's 747 Classic customers (the target market for the B777, in competition with the A330/A340). My 747 Classic F/Os, that are still flying, are predominantly on B777s.


777-Yoke Vs. Sidestick (http://www.fortunecity.com/marina/invincible/249/yokevsti.htm)


With all due respect, and I really value your contribution to this thread, and which is always insightful, I think a better analogy would be the migration from horse and cart to the motorcar - whether reins or wheels, the retention in front of you over which you clearly control (whether horse or machine).


We all know that "feedback" to yokes is artificial, and has been for decades, but a yoke emphasizes control (pleases Joe Sutter!).

The argument, for those that are not "fans", is that the SS regime inadvertently disconnects the PF from the aircraft and (at least without interconnectivity to the other SS and with artificial feedback through the SS to the PNF) from the other pilot - it is a system operator tool, rather than a pilot control tool, if I may put the argument in those terms.

I am undecided because overall Airbus are excellent aircraft with an excellent safety record (particularly if you remove the "human interface" crashes from their list of casualties, and Boeing have had more than a few LOCs). I also take your point that the SS came out of the USA through the F-16.


None of this would of course matter to this thread, if the pilots were at one with the A330 comprising AF447. But this is currently very much a point of contention...

ChristiaanJ
26th Aug 2011, 21:07
WW,
Thanks for the link.

Mr Optimistic
26th Aug 2011, 21:13
The stick v yoke argument is irrelevant to this isn't it ? Ditto analogue v digital displays. The logic that increased automation has reduced the necessary total human capacity on the flight deck would seem more fundamental (the arithmetic supporting the argument that any given level of safety can be achieved with fewer people eg no FE owing to the automatics). Fine when the automatics are present and correct, not so solid in an accident sequence.

infrequentflyer789
26th Aug 2011, 21:20
"When we went from horse-drawn carts to motor vehicles, did we attach ropes to the front axles and steer with that (because after all, that's what people are used to), or did we design something more appropriate for the technology?"


Careful, the early cars were actually steered with tillers - just as people were used to in boats. Steering wheels came later, but again the pre-existing nautical usage is not hard to spot...:)

AlphaZuluRomeo
26th Aug 2011, 21:23
Did I win ? :E
Nice :D
But, as you noted, that's an aircraft. I do not know of any manufacturer which have already made a better one (i.e. not prone to human errors, nor physics laws)

Welsh Wingman
26th Aug 2011, 21:24
A complete tangent, for which I apologise in advance to all others, but what did Andre Turcat make of a SS on the test SST?

We ended-up with ram's horn yoke, FBW and elevons with artificial feel.

Was there any significance to the final choice, given that aircraft type went under rigorous testing unheard of today (sadly to post-oil crisis commercial disaster, compare with hurried into service DC10)?

ChristiaanJ
26th Aug 2011, 21:34
A complete tangent, for which I apologise in advance to all others, but what did Andre Turcat make of a SS on the test SST?I'm not even sure Turcat himself flew F-WTSB with the sidestick.
But the test flight reports were positive (IIRC, will have to look through the report again), which says a lot, considering the general praise of other pilots about the manual handling of the aircraft with the conventional 'ramshorn' controls.

The side-stick on F-WTSB was never really intended for use on Concorde. After the certification flight tests, F-WTSB was used for several other 'non-type-related' tests, and the side-stick tests were part of that, and indeed led to the A320 story.

Welsh Wingman
26th Aug 2011, 21:55
It has only become "SS v yoke", which is somewhat of a misnomer, because the AB implementation of the former does not mirror the traditional characteristics of the latter and the flight crew never diagnosed the stall.

The human factors/CRM/cockpit discipline issues that arise out of the AF447 tragedy, as regards the SS, are the absence of artificial feedback (to the PF and through interconnectivity to the PNF) and apply equally to the throttle feedback.

Enough to fill in the missing pieces of the jigsaw for the PNF, if only enough to brief the returning CDB to get him over the line....?

Diagnose the stall and get to work on ND and the THS "problem", as per the related thread on AF447, although it feels somewhat esoteric and academic in the context of a flight crew that never diagnosed the stall. But an interesting post by Owain Glyndwr on that thread, for those of you aerodynamically inclined......

Mr Optimistic
26th Aug 2011, 22:12
WW, thanks, yes appreciate that many things didn't help and that such help shouldn't really have been needed. A bit surprised (given the significance of the Capt's absence) that the more general question over whether two is enough isn't on the table. Noted that another company operates dual Capt/FO type arrangements - this sounds comforting to me as Pax.

Welsh Wingman
26th Aug 2011, 22:15
Interesting. I can see a transition from yoke to SS as evolutionary, with the right training, but the loss of artificial feedback (including interconnectivity to the PNF, and also the throttles) makes it revolutionary and makes me, as British, about as enthusiastic as Margaret Thatcher having to go to the bicentennial of the storming of the Bastille!

Remove the flight engineer (the one flight deck officer devoted to aircraft systems), insufficient training for high altitude (including emergency), limit by-hand flying, lack of urgency about replacing a part critical to the aircraft system (pitot tube) and then give the pilots no blatant mechanical feedback through the SS and throttle at the moment of maximum sensory overload in the middle of the night during a reinforced oceanic cruise (sadly without a visual horizon, and sufficient to ignore a stall alarm albeit complicated by the 60knt/AoA design floor). I am not saying the flight crew should not have done better, because my thoughts can be deduced from my previous posts, but to keep chipping away at the margins...?

Would you deliberately design this from the outset, irrespective of the CRM issues on this flightdeck? Lyman (or whatever alias!) would not, and quite a few of you might find yourself uncomfortably in agreement with him over this.......

DozyWannabe
26th Aug 2011, 22:22
The human factors/CRM/cockpit discipline issues that arise out of the AF447 tragedy, as regards the SS, are the absence of artificial feedback (to the PF and through interconnectivity to the PNF) and apply equally to the throttle feedback.

Enough to fill in the missing pieces of the jigsaw for the PNF, if only enough to brief the returning CDB to get him over the line....?

Again, a valid opinion - but certainly not an incontrovertible fact based on the evidence available. We've had an A330 successfully deadsticked into the Azores, an A320 very famously deadsticked into a near perfect landing on water, and conversely we've also had several yoke-equipped aircraft (B727, HS Trident, B757) go into a full stall and crash despite all manner of stick-shakers, stick-pushers and so on giving tactile feedback to the crew (which at least one crew mistook for Mach buffet). It was discussed at length in both the Tech Log thread and this one if you want to check it out.

The upshot of this admittedly anecdotal evidence is that the tactile feedback channel may not be the panacea for communicating aircraft behaviour to pilots that the pro-feedback brigade seem to think it is.

@WW (above, regarding "would you design...") - As I said in greater detail in an earlier post, Gordon Corps certainly didn't mind - ultimately he was the senior engineering pilot who signed the design off, and he was nothing if not a first-rate, safety-conscious pilot of the old school. The design itself was specified with input from pilots of all levels, from the line, through engineering pilots and test pilots.

@CJ (below) - when would it activate? I could see it being annoying if it was on all the time - perhaps when the trim passes a certain threshold which varies with altitude and AoA?

ChristiaanJ
26th Aug 2011, 22:33
The upshot of this admittedly anecdotal evidence is that the tactile feedback channel may not be the panacea for communicating aircraft behaviour to pilots that the pro-feedback brigade seem to think it is.Yes, no.....
Personally, I'm still wondering about the absence of the "bicycle bell" on the THS trim wheel.
Not tactile feedback, of course, but still feedback.

Welsh Wingman
26th Aug 2011, 22:51
Mr Optimistic

Now that is optimistic!

A fully reinforced (i.e. duplicated) flight crew would be preferable, ceteris paribus, but there are the same cost issues that ended the flight engineer (who would also have to be reinforced). Even a relief CDB and F/O is not the end of it, because you have the Van Zanten/Meurs CRM issue at the other end of the spectrum to AF447.

Takata set out the AF procedures at the time of AF447, and how the junior F/O in the RHS came to automatically become PIC. Interesting, and thankfully no more....

DozyWannabe

There will be nothing "incontrovertible" about AF447! Look at the number of pages on this secondary thread....

I believe, and have strong views on the point, that the need after Stony Point was to ram into every pilot's head that, before discounting a stick shaker (yoke or SS), that an uncorrected stall = death. End of. Be absolutely certain, as you watch your VSI plummet.

A SS with the same function is not a philosophical problem for me, even if it is to others, but a deadstick makes me nervous. As you state, you can land an A330 "glider" with a deadstick and airmanship. It is the additional scanning at the moment of maximum stress in an emergency that is unwelcome, when feedback and interconnectivity aid cockpit discipline in a cockpit that needs assistance.

If Boeing and Airbus, in unison (even if they preferred feedback yokes and feedback SSs respectively), had addressed stall issues, I would like to think that 9L/CJC 3407 could have been avoided (let alone AF447).

I have some difficulty with any argument from anybody on this forum that, if the LHS SS had been moving in tandem with the RHS SS as a result of the PF's inputs, it would have made no difference to what the PNF would have said and done (particularly in the initial critical pre-stall phase). PNF was "nagging" PF, without such feedback assistance, instead of calling the UAS drill.....

P.s. re: "design" - I mean the totality of that paragraph. What Gordon "signed off" is not necessarily what he would have preferred, and he could not possibly have envisaged the industry changes over several decades on the human interface issues that have arisen.
P.p.s. I would almost go so far as to secondary alarm the THS trim wheel whenever you depart from normal law in an AB, to keep the flight crew cognisant of the manual trim issues.

Welsh Wingman
26th Aug 2011, 23:00
Please don't get me started on the THS trim wheel tonight, or I will never get to bed..........feedback, yes........but leave that one for another day.

Mr Optimistic
26th Aug 2011, 23:03
But didn't the PNF take control only to have it snatched back, and this with the Captn present ?

Lyman
26th Aug 2011, 23:14
The direct cause of 447's crash will not be "direct". To get to a single vector is impossible.

A starting point would be the untoward (and shamefully anticipated) dump of the a/c control into the hands of the PF. It had happened, though likely not ever in such piss poor conditions. This makes the foot dragging inexcusable.

There are no explanations, only excuses. Because all the precautions, all the preventions, were inadequate. How about that, then? One cannot focus on a single iteration; they were without exception, re-iterative.

In a perfect World? OK. PARK IT. FIX IT. Won't happen. I cannot say it cannot, but it won't.

That is why TRAINING is such a whine. And since it is a whine, it is dishonest, and arguably criminal. It is also self incriminating, the Pilot group does not self train.

Airframe?

The two or three glaring problems won't be fixed, too expensive.

What was known, and when did it become so? Ask that question of Socrates, or some modern day Solomon. It will be ignored.

PITOT. STALLWARN. THS. UAS Procedure. (This last, alone, food for an action at LAW that would cripple the players, and indict the Authority.)

When "corrections" can be applied before the engines have cooled, does one not think that the problem was a priori?

DozyWannabe
26th Aug 2011, 23:26
But didn't the PNF take control only to have it snatched back, and this with the Captn present ?

Yes he did, but it was approximately 5 seconds before the Captain arrived, the PF took it back after less than 2 seconds, the PNF presumably turns to talk to the captain as he comes through the door and in the intervening time (approx 2 seconds after the Captain enters the flight deck - so the Captain should have heard it, albeit briefly) the stall warning stops.

I've not put this together before, so it raises some very interesting points and questions.


At the start of the sequence, as autoflight trips out, the PF makes the callout "J’ai les commandes" ("I have the controls").
The PNF was preoccupied with the return of the Captain (and unless I'm reading it wrong, increasingly unhappy with how the aircraft seems to be being handled) before finally deciding to take the controls himself, just before the Captain arrives. He says "Commande à gauche" ("Controls on the left"), takes priority and makes a small nose-down and left correction.
Now I thought that statement was ambiguous to start with, and was roundly told that it meant he was making a left-stick input. Now I've seen he takes control, makes the callout *and* makes that input at the same time, I'm unsure again.
Was he aware that the PF had taken back the controls without announcing it? (interconnection aside, that's a flagrant breach of procedure on the part of the PF *unless* he interpreted the PNF's "Commande à gauche" callout as an order to apply left stick and as far as he's concerned still has control. Can anyone clarify what the correct callouts should have been?)
The stall warning stops just after the captain arrives, and just after the PNF took the controls and made a couple of small corrections (which were correct, but nowhere near enough). Does he think his corrections have solved the problem?
Either way, that's an unfortunate set of time-critical coincidences.
Five seconds after that, the PF makes his "crazy speed" remarks and starts to throw the speedbrakes out, prompting an emphatic warning from the PNF not to do so. How much more pressure and cognitive load can one guy take?


Hmmm...

@WW - I think the lack of properly defined command gradient is a much bigger problem in the case of this incident than the feedback issue. I say again - same thing has happened plenty of times with interconnected yokes and it made no difference to the outcome.

Lyman
26th Aug 2011, 23:29
Interconnected ss may have made it worse, (in the moment, and not anent outcome). Mutiny was alive, and there was never evidence of a quiescent Flight Deck, only harping, stubbornness and questions asked rhetorically instead of "teamed". Sad. I think the Captain's call and arrival hurt the situation, did not help. It solidified the stubbornness, instead of loosening it. It gave a third leg to the stool of confusion.

Welsh Wingman
27th Aug 2011, 00:20
The PNF in the LHS, when the A/P disconnected, could well have been asleep until sometime between 1H 55 and 2H into the flight. The A/P disconnects at 2H 10 05, the stall alarm sounds at 2H 10 10 and the PNF is "not happy" by 2H 10 27 and starts "nagging" the junior F/O P/F and PIC re: airspeed and altitude.

By 2H 10 49, 2 seconds before the stall alarm triggers again, he is anxious over the failure of the CDB to return to the cockpit, but does not take the controls until 2H 11 38 (maximum height was at 2H 11 10), and then "relinquishes" control as the CDB enters the cockpit 5 seconds later (and the stall alarm ceases a further 2 seconds later due to the AoA design issue). AF447 hits the ocean at 2H 14 26.

All over - 4 minutes 21 seconds from start to finish, with maximum altitude reached 1 minute and 5 seconds after the A/P disconnect.

I can see little in the CVR (admittedly little has been disclosed to date) to suggest that the PF would have saved the aircraft under any system. He had experience, in addition to his training, working against him. My yoke/SS debate with DozyWannabe, or rather our feedback debate, is under what circumstances, or under what amended system (if any), the PNF might have been induced to take control and assume the PF role in the first 30-60 seconds and stabilise the flight through P+P (alternatively, been in a better position to brief the returning CDB - albeit it was a rapidly worsening scenario by that stage, stalled and falling). Irrespective of AF procedures, he had the ultimate incentive. Additionally, in the interests of wider airline safety, another PNF in such a scenario (however widely you define "scenario").

One critical point to consider - better feedback from the aircraft and something more direct than another alarm or FMC screen i.e. seeing clearly what the PF was doing with his RHS SS, plus what was happening to thrust and trim. To what is the aircraft responding? Once the VSI is hurtling downwards, more difficult but enough for the CDB/PNF to diagnose the stall (despite the on/off stall alarm confusing them, with no AoA indicator/BUSS). My own view is that the CDB did not take the LHS because he wanted to step back and get an overview of what had happened (other than the aircraft "had gone mad" - my words, not from the BEA report).

Welsh Wingman
27th Aug 2011, 00:48
"Mutiny was alive".....

My instinct - if PNF had decisively taken command, PF would have willingly acquiesced and happily run the UAS drill.

Put yourselves in the shoes of the PF - he was being "nagged" at by a PNF fretting over the CDB's ongoing absence. Inspiring, when PF is PIC under AF's "interesting" chain of command procedures at that time?

So, if not an interconnected SS, what was needed re: inducing PNF (in the context of experience/training/the cricket stall alarm being ignored) re: what the PF was commanding through his SS and its effect on altitude, pitch, AoA, thrust and trim.....?

DozyWannabe
27th Aug 2011, 00:55
The PNF in the LHS, when the A/P disconnected, could well have been asleep until sometime between 1H 55 and 2H into the flight.

He'd just come back from what he called a "doze", why would he need to sleep again? Judging by the CVR excerpts, he spends the first few minutes being briefed by the PF, with several references to REC MAX (which the PF's inputs eventually cause them to exceed, but this is never noted), and makes what looks like preparations to get around of the worst of what the weather radar is presenting by suggesting a minor course change and reducing the display range of the PF's weather radar - thus increasing resolution of the immediate area, followed by preparing for a possible bumpy ride by moving from managed to selected speed, selected at 0.8 Mach, (which I think is what he means by "computed" and "manual").

Fundamentally I'd say he seems pretty plugged in and situationally aware.

Welsh Wingman
27th Aug 2011, 01:07
I don't mean PNF is still tired, but he entered the cockpit after his rest break a mere 10 minutes before it all kicked off (i.e. UTC-3 is Brazilian take-off time, the layover destination). The first 30-60 seconds after A/P disconnect was decisive, because thereafter you are graduating from hurdles to the National fences.....

DozyWannabe
27th Aug 2011, 02:14
Sure, but the main problem from that perspective judging by the 3rd Interim Report is that according to the book, in the situation whereby the crew consists of a Captain, F/O and relief pilot (i.e. not another Captain) the Captain is supposed to make it explicitly clear which pilot will have which responsibility and also, importantly, determine the parameters by which one is allowed to take control from the other.

The informal nature of the handover after the PNF takes his seat, compounded by the Captain's question to the PF if he had the requisite qualification to be relief pilot (implying this had not been determined earlier, and also according to the BEA implying that the PF is now relief pilot), all indicated a rather cavalier approach to the procedure, so the PNF is quite rightly getting more and more agitated over the handling of the aircraft by the PF after A/P disconnect. Possibly he fears getting written up if he oversteps his bounds - at this point the aircraft is climbing and bucking slightly from turbulence but is not in any immediate danger.

I suspect he initially summoned the Captain not only because of his concerns over handling following A/P disconnect, but also to clarify handover procedure. The report states that under normal circumstances the PNF would have taken on the relief pilot role, which implies that the current state of the flight deck hierarchy is unusual. 2 seconds after "where is he? er", the stall warning sounds continuously for approx 56 seconds, for 54 of which the Captain is not present and the PNF has to process the change in situation from getting written up if he does something he's not supposed to to potentially being in mortal danger if he doesn't do something.

As I said earlier, human factors experts are going to be pulling this one apart for decades. In many ways it's even more complicated than Tenerife, but the ultimate similarity looks to me like getting over the "If I do something I could hurt my career" thought to transition to "If I *don't* do something I could lose my life". The PNF appears to make this realisation 7 seconds before the Captain shows up, but then defers to the Captain on his arrival while the PF continues to make the situation worse. He's satisfied his inital worry because the Captain's here to get things sorted, but in the meantime the situation has become considerably more perilous.

I find myself agreeing with Lyman (whodathunkit?) - the arrival of the Captain ended up coming at a bad time.

Another similarity with Tenerife is that the PNF in this case, like the F/O in the Tenerife case, does not feel he has the authority to physically intervene, but instead tries to resolve the situation verbally while his mind is working through the problem.

AF447 : "You're going up, so go down", "Above all try to touch the lateral controls as little as possible eh"

KLM4805 : "Wait, we don't have our ATC clearance [to PF]", "We are now (at) take-off [to ATC and PA1736]"

Welsh Wingman
27th Aug 2011, 02:49
A cavalier approach to an interesting system. Link to Takata:

http://www.pprune.org/tech-log/456874-af-447-thread-no-5-a-77.html#post6619789

Lyman
27th Aug 2011, 03:10
There is nothing whatever crisp, decisive, or authoritative about the flight deck conditions post handoff. Well, "I have the controls" is decisive."

If one comments on a problem, and takes no action, it is considered a suggestion. The call to Captain came when chain of command was the worst problem they were facing (to them). So call the Commander, and let him sort this out? FFF. First, F n FLY....... Shall we have a meeting? then a vote?

How does this happen, and in its evidence here, how pervasive might it be? The a/c is a dream to fly, solves all problems, so why not have a spat? Clearly, there is no pressing anxiety, no focus. If one thinks that this a condemnation of the flight crew, look past one's conclusions, and ask: How is the Culture derived, enforced, and maintained?

"So, (SO?) we've lost speeds.....Alternate Law." These crew are describing in pathetic tones what is wrong with the culture at Air France, not what is wrong in this cockpit. The a/c did what it was supposed to, and so did crew.......

So if we are to continue to foster and tolerate Flight OPS in this manner, a suggestion, go DIRECT, because if that doesn't get one's immediate attention, don't bother calling the Captain.

Everyone gets a participation ribbon, and applause for doing what is trained....

Whatever happened to leadership? The Plane can't lead, and followers need a leader. Initiative comes from confidence, and confidence comes from experience. "What am I doing now?"

ChrisVJ
27th Aug 2011, 05:44
Apologise for my ignorance however something occurs to me.

To draw a simplistic parallel many pilots today do not practice spins during their PPL because the FAA etc discovered that more planes were being lost in practicing than in inadvertant spins during regular flight and though we all practice developed stalls most of our time is spent diagnosing initial stall and preventing it's development.

When Airbus pilots practice stalls in the Simulator do they actually practice fully developed stalls? ie, all the way to less than 60 knots and where the stall warning turns off or just to the point of stall warning and then lower the nose and recover. If that were the case it is relatively easy to imagine that when the PF lowered the nose and the alarm sounded his reaction would be to raise it again, hear the alarm suspended and conclude that lowering the nose was dangerous.

exeng
27th Aug 2011, 06:50
all the way to less than 60 knots and where the stall warning turns off or just to the point of stall warning and then lower the nose and recoverOn the 320 course with a UK carrier - just to stall warning and recover - nowhere near the invalid airspeed area.

amos2
27th Aug 2011, 09:59
Do any of you lot of wannabes really think that any professional airline pilot is the least bit interested in all of the nonsense that you are writing?

indeed, can I ask?, who are you writing to?, yourselves, each other?, or perhaps some sky God you worship?

Give us a break, go and watch TV or latch onto some other cause! :(:(

BOAC
27th Aug 2011, 10:30
On the 320 course with a UK carrier (Noted :ok:). Let's face it, that SHOULD be enough given a basic competence in the licensing and training of airline crews.

grizzled
27th Aug 2011, 11:13
BOAC...

"SHOULD be enough" would be correct if training and licensing were the same (or even similar) to the days when folks like you were trained. Sadly, it just ain't so today.

DOZY...

Your post #3318 sums up well (IMO) one of the major contributing factors to this convoluted, intriguing and tragic chain of events which we call an accident. I'm certain you are right about the human factors discussions going on for the next few decades -- as will the discussions of other aspects of this occurrence, hopefully.

LYBEARMANFOIL...

I have removed my comment, as Lyman has modified his post

AMOS2...

There are plenty of well thought out posts, even well posed questions from SLF. Just try to weed as you read and mentally toss out the chaff, rather than let it ruin the harvest. (Though it does make one wish sometimes that there was a better format than pprune. When it comes to aviation there isn't.)

There are many of us who don't post nearly as much as we used to (especially re AF447) but we do read the threads. And we PM a lot. (Maybe I'm just lucky that I find a few ounces of whisky more therapeutic than posting.)

RAT 5
27th Aug 2011, 11:20
Firstly, given there are >3300 replies here, I have not read them all. I'm picking up on the confusion caused by reducing attitude and a stall warning sounding, and then hauling nthe nose back into a stall with no warning going off. There have been various accidents where pitot or static vents were blocked, ADC's malfunctioning or ADI's freezing. In many of them there was height and thus time to spare. There was significnat confusion and matters made worse because the crew did what they normally did in decyphering the instrument information. From TV reconstructions of the incidents at no time did anyone stop and say "this can not be correct. My aviation training and gut feeling tells me this is wrong. The laws of physics and aviation have not suddenly changed. So lets go back to basics and find out what is really going on." e.g. inputting nose down elevator in +ve G flight does not cause the altimeter to show a climb or speed to reduce: reducing attitude does not cause an a/c to stall. Something in all the electronic wizardry is scrambled; the computers speak with forked tongue. Let's pause and use our knowledge to find a safe place and then analyse what we know and what we see. There is time and there are other sources of information for us to consider to resolve the apparent confusion and false information.
How we introduce this philosophy into training is a big question, but if it had been there in many of the fatal accidents perhaps they would have been survivable. In all the cases I've seen, and am thinking about, the a/c was flying and controlable. It was the pilots, presented with incorrect performance parameters, who crashed the a/c. I know this sounds easy sitting in the arm chair. Would we have acted so calm in the reality? I don't know, but I believe it can only be helpful to introduce some of these scenarios in recurrent training. Every 3 years in recurrent training we are supposed to tick the 'flight instruments' box. I have never been given such a scenario, only a very simple unreliable airspeed problem, which was not flown to a landing, or another simple problem. When I wrote recurrent training programs I searched the real crash causes and included them in the syllabus. The crews often knew of the crash and were intrigued to learn from them, practically, not just reading the reports. There was real purpose in the training, not just box ticking. Sadly, it is no longer in my remit. Do others have any useful training experiences which could help with this dilema?

PJ2
27th Aug 2011, 20:05
The problem is far far wider than Toulouse......Yes, indeed the problem of the handling of automation in the industry is far broader "than Toulouse" and the evidence for this is widely available and has been since the mid-1980's. The problem stems from an infatuation with the huge potential cost-savings, with added flight-safety benefits. On the whole the history of automation's introduction and acceptance by the industry, particularly those who use it on a daily basis, has been successful and the accident record supports this view as does the wide acceptance of those who initially transitioned through the Lockheed L1011, B767/757 to the B777 & A300/A310 to the A320/A340 and A330. The numbers tell us that the initiative is successful by both cost and safety standards.

It may initially seem obvious but an "automation accident" could be understood as a "cognitive" accident as much as it may be understood as a technical accident. This is in contrast with past causes which usually involved weather, navigation error, mid-air collision or CFIT. In the end it's all "cognitive" but the character of engagement with automation where "something is done for oneself by a system in which many though not all decisions governing outcomes are resident within the system and do not emerge from oneself" is materially different than the "bread-and-butter cable-and-pulley pilot engagement with/without hydraulic support" traditional approach to solving the problems of controlled flight.

The material difference is, automation intends to solve "the problems of flight", (this description requires a lot of unpacking), which were ordinarily understood intuitively from long experience and a few rushes of adrenaline. Sometimes a pilot is solving the problems of automation which in turn are solving the problems of flight but for the most part, because of the long history of very robust research and development in the design and implementation of "automation" per se, the two complement one another -again, the record clearly demonstrates this - automation has come to terms with both cost priorities and safety principles.

But there are exceptions, some unforeseen, a few bad design decisions and as always, the human factor...that category of events which occur because people are people and sometimes subvert or otherwise use in the most imaginative but unanticipated ways, systems which have the best and most honourable design foundations and technical intentions.

I wouldn't think the term "ergonomics" would be helpful in delineating the problem for the purposes of study, but how the question(s) is/are enframed always determines the nature and character of the answer so it is important to understand how to ask the question. (That's just another way of saying, "eastern rats perform better for eastern psychologists", or, "to a two-year old with a hammer, everything is a nail").

Against this unfolding automation trend from the early 80's on, AW&ST ran a series of very well conceived and written articles on automation in 1995. (I've made PDFs of those articles but don't have a place to post them yet.) Essentially, the articles are saying the same thing as we are today, which begs the question concerning "more automation?"

I am hearing from good friends in the industry that an automatic response to TCAS events is being considered. The reason is, there are numerous incorrect responses by flight crews to TCAS RA events. Designers and the industry are reaching for more automation.

Here's a clear example: In running a FOQA Program, we designed 28 specific events which enumerated and otherwise captured, very specifically and in detail, all TCAS events and crew responses. We were motivated to do this because both Lufthansa and Air France had done this years earlier, (1994, IIRC), and they found what we were finding in our budding Program.

The solution is comprehension and training, not more automation, but that argument seems to have been superseded by the decision not to use these 28 events to determine what and why TCAS responses weren't always correct, in favour of an automated response. I have not studied the Uberlingen accident sufficiently to know whether an automated response would have avoided the collision or not, but that is not the issue: the issue is a decision to reduce margins of error because it is now possible to do that while demonstrating that automation can produce "acceptable levels of safety".

And so this is another aspect of automation which is quite different than the one "we old guys who flew steam", faced. We now have young people, (20's, 30's) who have never known anything but glass, FMCs and varying levels of automation. For many, their first jobs were as likely to be on automated aircraft as on a Beaver flying hunters, fishers, oil-men and arctic workers into strips which demand a very high situational awareness, physical and mental sharpness and for which automation remains an infant.

The question of automation has always been enframed in traditional ways when the real problem is how the pilot engages, or is engaged by, computer solutions to the ancient, unchanging problems of aviation. For example, the article written by someone who claimed to be an experienced A330 captain and who said that flying the A330 was just the same as playing a video game may have described one tiny aspect of the character of this interaction but missed entirely, the fact that if one's competence with this or that video game is questionable it is wholly inconsequential while flying an aircraft, however done, is not. Others have said this, but the act of digital flight is a twice-removed cognitive step from handling the airplane.

The best example is one we all know about...the analogue wrist watch that always tells us "how much", and the digital equivalent which requires a higher level of cognitive engagement to first calculate, then construct a model of, then interpret one's own situation on top of such model, before one can determine, "how much". What is the meaning of "clockwise", or "half-past three" when one is interpreting a rolling series of numbers?

These are not insurmountable but as others have said very well here, such changes to digital flight do require different training methods, practise and cognitive responses.

People respond best to images, most strongly when such images "tell a story", and not to single digits from which "how much" must be intellectualized and then re-expressed as an image which then conveys "the story" which is usually a specific metric as compared against the whole, all in one image. The airspeed and altitude tapes do this to a certain extent already, but the TCAS response described earlier, seems to have more than its share of incorrect responses primarily because of the way the RA information is presented on the PFD.

TJ Harwood, this is all off the top of my head and is intended as thoughts against which others may push and change, dismiss or add to. As a pilot of these aircraft for 15 years, my approach was to "look through" all the automation to see what the airplane was doing and that meant airspeed, altitude, rate of climb/descent, heading/track and engine thrust, and if all of these were what were needed for the job immediately at hand, and they were trending (for the next ten miles or so) in the right direction (and "no changes" is a trend), then I let the automation do its work.

I think that is what was meant when someone else here said that automation was an assistant to the pilot; it is most certainly not a third or fourth pilot but as that dangerous mentality gets even more established, especially with managements and pilots who have flown nothing but automated aircraft, the way back becomes very difficult because fear builds upon fear and soon one is afraid to fly. Seen it, and I doubt very much whether this was ever the original intent of those who contemplated using microprocessors to solve the problems of flight.

I have already referenced some whom I believe have some important things to say. The interesting thing is, we are not hearing from many pilots, and I think that is because they're getting on with it and flying their airplanes, treating it just as is described above...For most pilots, automation is transparent to the task at hand, and instead we have the age-old aviation problems remain, which the major innovations of SOPs, CRM, Threat-and-error management and thorough training, as well as EGPWS, TCAS, ADS-B/CPDLC, SatNav are all intended to resolve and for the most part, do.

I look forward to reading others' views.

Lyman
27th Aug 2011, 21:00
Automation, per se. On its own. An excellent solution(s). After twenty years, the proofs are easy. It int the problem. Seeing it as a solution is the proper perspective (imho). So why the LOC, the less than intuitive reaction to what have thankfully become rare events?

Dependence, and an as yet unappreciated chasm between the solution, and its application. The box is a better flyer, but the pilot is a better thinker, (read problem solver)

Ahem...."Level off and troubleshoot".

OK, that is called "management" in my country.

What else is missing? Leadership. Leadership cannot be drilled, it is innate, and when there is need for it, and it isn't readily available, people will occasionally die for its want.

BarbiesBoyfriend
27th Aug 2011, 21:04
PJ2. You've tried to put a complex subject into words. It therefore reads a bit like a lawyers letter.:)

I agree, but put more simply- the autos should never be used to do stuff that the pilot can't do. Firm.

At the start of the 'automation' era, there was never any question of this. The pilots were well trained and highly able. Plugging the AP in just 'unloaded' the pilots allowing more time and capacity for other tasks or just a wee rest. As they still do of course.

But, nowadays, skilll levels aren't what they used to be. Many pilots who might once have managed well without autos would struggle if suddenly deprived of them. (the autos mask the FACT that their flying skills are dormant). They've become over-reliant on the autos.

Other, newer pilots DEPEND on the autos and are up **** creek as soon as the autos are off. They frankly rely on the autos to get through the day!

Whether you see any problem with the above is very much a matter for you. But that is how it is these days.

If the autoflight system falls over at the wrong moment- and when they do, they sometimes do it big time, the modern auto-dependant pilot has damn little poling experience to fall back on. As AF447 demonstrated.

Unusual attitude? loss of data? bit of turbulence?? Having to hand-fly (as we quaintly call it nowadays!)????

What they going to revert to? What experience are they going to fall back on?? How much AP OFF actual 'stick time' have they got?? 1% or less of what's been logged!

In other words- 'Damn all'- that's what.

Autos: 'great'! Let's have them and use them.

But let's teach people to fly too though, and KEEP them up to speed with their hands, so they're READY. STRAIGHTAWAY! when the damn things take a day off.

It won't be that expensive.

MountainBear
27th Aug 2011, 21:14
In the end it's all "cognitive" but the character of engagementThis is typing disguised as thinking. It's a mind that's more interested in appearing like it's thinking than actually thinking.

When we write "A=B" we don't mean that the letter A shares the same graphical design as the letter B. Math is a symbolic language. When we write that A=B we mean that at some level of abstraction A shares some property (but not a unity) with B. Thus for every A=B there is also the contrapositive that A != B.

If in the end it's all cognitive then A=A a statement which has the same informational content as "everything is everything". Nor is this reality changed if one changes "the character of engagement" so that there is some other symbol between A and A: A+A, A-A, A*A.

Nothing that you wrote is on any use for a person, a pilot, or a judge as a tool for decision making. I don't know which is worse: the nihilism that is so en vogue among the political set or the nominalism (http://en.wikipedia.org/wiki/Nominalism) so prevalent among the intellectuals.

PJ2
27th Aug 2011, 22:15
BBB;

Yeah, probably reads too "stiffly" but it's an entry into the ongoing discussion and may or may not be helpful. Another candidate for deletion, probably.

Mountain Bear;

A vigorous response and frankly appreciated. I would expect no less from the Analytical Tradition. There are fields in which that kind of dialogue is useful and relevant but not in discussing cockpit behaviours.

deSitter
27th Aug 2011, 23:02
That's just BS - A=B means A and B stand for one and the same thing. Period.

DozyWannabe
28th Aug 2011, 00:00
Yeah, probably reads too "stiffly" but it's an entry into the ongoing discussion and may or may not be helpful. Another candidate for deletion, probably.

Not at all. For someone like myself it provides a balanced view of the issues from the perspective of a pilot, which is something I can do my level best to empathise with and "put myself in the shoes of" based on theory and my few AEF/AEG hours (along with a career path which also primarily uses me as a cog in the mechanism, despite my training and experience giving me more latitude if I need it), but can never wholly replicate, which is why any post I make on here automatically comes with caveats.

It's good stuff as far as I'm concerned - more please!

That's just BS - A=B means A and B stand for one and the same thing. Period.

Not quite, as always context is everything. As far as informatics (i.e computer) algebra goes, it depends on the definition of A and B. If they are both constants, then what you say is true (or to elaborate, A and B share the same value, even if they do not refer to the same "object"), that said, if two constants are defined as having the same value, then one of those constants is effectively redundant. If either are variables, then the value of either can change at a later stage, rendering the expression "A=B" transient.

(Hark at me, talking discrete maths at 2am on a Sunday morning - how rock'n'roll am I? :8)

(Noted :ok:). Let's face it, that SHOULD be enough given a basic competence in the licensing and training of airline crews.

Just noticed this - and you're right, technically it *should* be enough, and with the new stall recovery procedures one would hope this was a plugged "hole-in-the-cheese"*. However, non-practiced responses and training to correctly identify an *actual* stall still worry me. I've said this before (Hell, at this point there's very little I *haven't* said before, so thanks for putting up with me), but how much of an airline's training budget would be eaten up by once a year taking a single-engined trainer up and practicing an *actual* stall recovery or ten? As a touch-typist and guitarist I'm well aware of how much I rely on muscle memory - surely it must be similar with pilots?

* - I'm aware that the emerging new techniques in determining behaviour patterns, including our own PBL's "why-because" work, give a far more detailed and complete picture of accident sequences, however I still think the "holes-in-the-cheese" method is a great way of rendering this stuff comprehensible to the layman, as well as requiring a few paragraphs to summarise, as opposed to a dissertation! ;)

Lyman
28th Aug 2011, 03:00
Taking your cheese holes a bit further, I would submit that any hole plugged before STALL makes improvements in STALL recovery rather a Red Herring. Nice, but doesn't obtain.

The hole to which I refer is the hole of Dependence on auto flight.

More specifically, a lack of preparation to address known possibilities for critical handling problems.

Dependence leading to disastrous initial mismanagement, highlighting a glaring insufficiency of Leadership on the Flight deck.

For me, it would be sufficient to address the procuring cause: the lack of skills in emergent situations, well ahead of Departure. (STALL, not push back).

This STALL, UA, etc, "Training" thing, sorry, is a ruse. Because what you want is more Rote drill, and SOPS; a track I predict further cements the problem in 'insolubility'.

PJ2 concludes the accident "began with the initial NOSE UP." That is not established at all, as he is in discussion with others whether "handling at drop" is indicated, or not. And that whether 2.5 or 5.0! By drill!

The STALL lacked conventional (!) cues, and "Recogniton of Approach to STALL" is well addressed in SIM; there is no evidence we should be supplying cadets with Schweizers, and spin training.

The shortfall is in Situational awareness, and that is not easy to expect, operationally, and given the aforementioned dependence on its hypnotic nemesis: Autoflight. imho.

Proviso. The Dependence to which I refer, is not flightcrews'. Crew are prevented from any reasonable solution to this dangerous dependence, and as I have pointed out: The PILOT GROUP DOES NOT SELF TRAIN.

READ: AIRBUS, AIR FRANCE.

jcjeant
28th Aug 2011, 13:02
ChristiaanJ
Originally Posted by jcjeant View Post
In fact the BEA explanations shown some things .. the complete failure of the BEA to conduct professionally a search for a disappeared plane (for this particular plane at least)
I take it then that you are an expert professional in underwater searches in the Mid-Atlantic (3000m depth plus), to profess such a judgment.
Do you work for Wood Hole? If not, why didn't you offer your services?

And I even suppose you don't know the expression "needle in haystack".....
Quote:
By the BEA failure in researches a precious time was lost for publish new recommendations
Slightly dumb remark.... Some recommendations HAVE already been published, and so far I haven't seen any crashes similar to AF447. What "precious time" was lost?
Quote:
The BEA explanations are not satisfactory...
Maybe not to you, since they don't match your conspiracy theories.
I doubt you've ever been part of a real accident investigation. All this deserves that we will investigate a little more this "conspiracy"

Scientific Report from the Drift Group
ESTIMATING THE WRECKAGE LOCATION OF THE RIO-PARIS AF447
page 134 Appendix 7: On June 2 2009 at 8h16,a possible pollution spot.... a SAR detected pollution spot...which does not have the characteristic elongated form of an oil spill coming from a ship. CLS and CEDRE experts were not able to understand its origin...

We have been unable, however, to relate this pollution spot to any impact point of the plane as determined from the debris and bodies found and the velocity fields estimated (whatever the methods). But, all our calculations, are based on the assumption that the plane hit the sea surface intact (following BEA expertise of the recovered plane remains).Source:
http://bea.aero/en/enquetes/flight.af.447/phase3.search.zone.determination.working.group.report.pdf


Here is what has delayed for nearly two years the discovery of the wreck
They know that the oil stain is not that of a boat
They knows that AF447 last know position was in the vicinity of this oil stain
This could have come from AF447
What made the BEA?
The BEA note this information
After some time (other debris found .. etc. ..) make it a study of currents, etc. .. (they say themselves very difficult given the fluctuating number of parameters)
After the experts work and reports .. they assumes several points (points found by a study based on assumptions) and find that they can't connect them with the oil slick seen before
So the oil slick has nothing to do with the accident ... BEA think .. but in mean time they dunno from where (not a ship at least) come this oil :uhoh:

Remark :
BEA know that the plane had broken in pieces when contacting sea .. and BEA know it was a certain quantity of fuel aboard.

So no need to investigate further more the area ... and all are going fishing far away .....
But so what?
Where does this oil slick
The lack of curiosity and good sense of BEA has cost 2 years ... not to mention money ... is not negligible in an investigation :eek:

DozyWannabe
28th Aug 2011, 16:39
@jcjeant - I'm pretty sure that the BEA themselves (whose speciality is investigating accidents) would have delegated the details of precisely where to search to the oceanographic survey and research teams subcontracted to do the work, as locating objects at the bottom of the se is *their* speciality.

Why this bitterness towards the BEA from you anyway? They seem to have been doing a pretty good and transparent job so far...

deSitter
28th Aug 2011, 16:57
Well in the wishy-washy world of software it may be acceptable to abuse math symbols, but in math "=" means what it means - A=B does not mean A is equivalent to B. There are symbols for equivalence and ways of dealing with classes of things that are equivalent. That's a different statement than equality. Maybe software is in such bad shape because the people who make it generally are not very good at math.

DozyWannabe
28th Aug 2011, 17:02
@deSitter: Discrete maths ≠ Pure maths. Now are you going to say something useful or just snark away?

jcjeant
28th Aug 2011, 18:03
Hi,

They seem to have been doing a pretty good and transparent job so far... Transparent ? .. so far I can agree (with some reserves...)
Pretty good ? my post tell me the contrary (they were involved in the researches)

HarryMann
28th Aug 2011, 18:07
Lyman,
Is it possible that you could change your language from Inneundo to Englishendo please... a bit is OK from time to time I think, but am oft struggling with your persistent form of flowery prose.

The shortfall is in Situational awareness, and that is not easy to expect, operationally, and given the aforementioned dependence on its hypnotic nemesis: Autoflight. imho.Cannot deny that Situational Awareness will be considered, and commented upon although maybe taking a back seat to CRM

BOAC
28th Aug 2011, 18:12
A lot of us are not............................:)

DozyWannabe
28th Aug 2011, 19:41
Pretty good ? my post tell me the contrary (they were involved in the researches)

And it's not their area of expertise, so I think holding the BEA largely responsible for the time it took to locate the thing is a little unfair.

For an idea of just how difficult it is to perform that kind of work, I'd recommend doing a little research on the 1985 WHOI/IFREMER expedtion to find the last resting place of the Titanic (among other things, now that info has been declassified).

Despite their best efforts, they only found it in the last two days of a mission that lasted several weeks (they'd have found it right at the start if not for a major blunder), and that was a 900ft iron ship in two major sections on a flat abyssal plain. The AF447 recovery expedition was trying to find pulverised scraps of aluminium from an approximately 200x200ft airliner in underwater mountains, which is an order of magnitude more difficult even with the advances in technology over the last 25 years.

For those that are interested, part of the classified mission involved the US half of the team going off to search for two sunken USN nuclear subs, which were easier to find due to exact satellite positioning at the time they sank. But what the US team discovered was that far larger and more widespread than the main pieces of wreckage was a debris trail of smaller, lighter items that trailed the larger wreckage as it sank. Pick up the debris trail, went the theory - and it would lead you straight to the wreckage.

Of course, all of the debris and wreckage in these cases came to rest on a more-or-less flat plain, so the trail was much easier to find and follow than it would be on the mountainous terrain in which AF447's wreckage was thought to be. The other major problem with mountainous terrain would be the fact that even if the flight recorder pingers were working, the sonar signals could bounce off the surrounding terrain, making following the trail even *more* difficult.

Lonewolf_50
28th Aug 2011, 22:11
Hazelnuts
For no good reason? Two apparently very brief occurences of stall warning were observed at 02:10:10 and 02:10:13 (page 29 of BEA#3).

Please, take a read of the post I made.

In that post, I discuss the outcome of the hypothetical that Clandestino presented, of simply applying five degrees nose up, at that altitude, as a sufficient response to UAS. It is not a critique of the AF447 events, which you and I can agree did not merely set the nose at five degrees up.

PJ2: Will need to chew on your magum opus entry before responding.

Amos: I'm gonna stay on your lawn.

jcjeant
29th Aug 2011, 05:03
Hi,

And it's not their area of expertise, so I think holding the BEA largely responsible for the time it took to locate the thing is a little unfair. Not at all.
BEA lead the investigations.
They hired experts
The experts suggest .. don't decide
The ultimate decision for choice search areas is in the BEA hands
They lead the investigation .. they are to be responsible of their actions and decisions
Fair enough

Gretchenfrage
29th Aug 2011, 05:28
Boring.
The whole discussion is turning in circles with stubborn defending of backyards. To each creature its feature it seems.

However, some arguments need some haircutting.

1. It is constantly argued, that most critics of the Airbus philosophy have never operated such, therefore are denied to be entitled to criticism (funnily enough many of those pretendants have not themselves either!). However, when critics appear that actually have flown A and B, they are cried down being romantic fossils wanting to go back.

A typical self serving distortion of arguments.


2. To counter the demand for certain improvement on A, the protectionists constantly bring up statistics pretending how much safety has improved. Statistics are made for a purpose, by people with an agenda. We tend to use the ones serving our cause and decrying the supposedly tampered ones that don’t.

If we start weighing statistics versus genuine concerns of involved professionals, then we are on a more than slippery slope.


3. Human error is a fact and will never go away. Trying to implement improved technology to mitigate the risk is fine, as long as we really acknowledge that this in itself can add new traps.
Implying that human error is only happening on the pilot side however is simply arrogant and dangerous. There is a widespread acceptance of pilot error, just as there is a widespread denial of design/engineering error (we all know why).

Engineers err, managers err, regulators err, as it is human. Or do they consider themselves beyond that?


Two discussed design errors:

A. The absence of feedback on primary controls seems to be such an error. The mere fact of the many critics on this thread should be concern that there is a malaise, bring up as many statistics as you want. The presence of pro (fill in any ME dictator) demonstrators can never wipe out the just as many opponents. Such issues must be addressed, belittleing them or brushing them aside approaches dictatorship.

B. The fact that an aircraft is allowed to disobey pilot inputs, even if they have screwed up badly beforehand, seems another error. As long as you need the pilot present as last resort (even just for lawyers), he has to have full authority over the system otherwise you created an operational oxymoron -> If the system malfunctions, the human has to intervene, but the system can still deny it.


Deal with it! But first reread my 3 points above ……

HazelNuts39
29th Aug 2011, 07:21
Lonewolf 50;

Please accept my apologies for misreading your post. I think we also agree that five degrees nose-up is not the optimum response to UAS at FL350.

P.S. Rereading your post caused me to wonder what condition would result from pitching up to 5 degrees. I think that in still air the airplane would climb until it is in 1 g level flight with pitch attitude and AoA equal to 5 degrees. Assuming constant total energy, that would be at FL375, 222 kCAS, M=0.7. The stall warning threshold in that condition is 5.7 degrees.

Lemain
29th Aug 2011, 07:28
I don't think this has been posted here yet. In any case, Wiki items are continually updated by folk -- some informed, some not...

Air France Flight 447 - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Air_France_Flight_447)

mm43
29th Aug 2011, 09:40
In any case, Wiki items are continually updated by folk -- some informed, some not...When they start talking in terms of "absolute time", I leave it. If they don't know what time to use, then use UTC, because that's what everyone else uses.

Lemain
29th Aug 2011, 10:00
When they start talking in terms of "absolute time", I leave it. If they don't know what time to use, then us UTC, because that's what everyone else uses. These Wiki articles are not written by any one person and anyone can modify them. You get it 'warts and all' -- there is much good stuff in there and some useful references. If you have the time, you can modify the errors and silly bits yourself -- you only have to log-in after registering and learn the special Wiki-speak code. Certainly don't dis any Wiki item for one or more faults...sort the wheat from the chaff.

Edit -- Have checked the Wiki ref to the BEA pdf which states all times UTC yet the Wiki article is using what it calls 'absolute time' which is defined as time from planned departure. We are not told who decided to use this 'absolute time' or why, but it is defined -- maybe there is a custom in another discipline (not aviation or navigation?). I don't know but it is defined and seems not to be just sloppy reporting.

DozyWannabe
29th Aug 2011, 13:51
1. It is constantly argued, that most critics of the Airbus philosophy have never operated such, therefore are denied to be entitled to criticism

Not at all, but it does rather dent the argument somewhat when someone says a design feature makes the aircraft difficult to operate when they've never operated it.

However, when critics appear that actually have flown A and B, they are cried down being romantic fossils wanting to go back.

Really? I'd like to see you provide a single example of that from a serious post on this thread or any other on the subject.

...people with an agenda.

Seriously? Pot, meet kettle.

We tend to use the ones serving our cause and decrying the supposedly tampered ones that don’t.

Except when you don't have any, of course - I'm still waiting for a single example of where force-feedback or lack thereof was a factor in a FBW Airbus crash. But of course, some of the design critics will always counter that it must have happened and subsequently been covered up.

If we start weighing statistics versus genuine concerns of involved professionals, then we are on a more than slippery slope.

Admittedly, all we have is anecdotal evidence here, but it suggests that the piloting community is split fairly evenly on the subject, with those who dislike the Airbus FBW philosophy largely from the group who fly other types. We've got at least one senior retired Captain who has flown many types, including the 'bus stating that most pilots he encountered once on the 'bus, had very little problem with it.


Implying that human error is only happening on the pilot side however is simply arrogant and dangerous.

Who's implying that?

just as there is a widespread denial of design/engineering error

So why did Boeing and Airbus change their Stall Recovery procedures, and why is EASA mandating a change to the Airbus autopilot engage logic despite it having no direct bearing on this case - if the possibility of engineering error is being denied?

(we all know why).

Not at all - enlighten us.

Engineers err, managers err, regulators err, as it is human. Or do they consider themselves beyond that?

Engineers certainly don't. The poor bugger who signed off the JAL123 pressure bulkhead repair was proof enough of that.


The absence of feedback on primary controls seems to be such an error.

Then bring your evidence, as has been asked many times by many people - because right now there doesn't seem to be any.

The mere fact of the many critics on this thread should be concern that there is a malaise, bring up as many statistics as you want.

In other words "Some people agree with me, therefore you should take my opinion as fact even though roughly just as many do not". Great argument.

The presence of pro (fill in any ME dictator) demonstrators can never wipe out the just as many opponents. Such issues must be addressed, belittleing them or brushing them aside approaches dictatorship.

So now people who disagree with you are likened to Gaddafi/Saddam supporters. Would you like a bigger shovel?

The fact that an aircraft is allowed to disobey pilot inputs, even if they have screwed up badly beforehand, seems another error. As long as you need the pilot present as last resort (even just for lawyers), he has to have full authority over the system otherwise you created an operational oxymoron -> If the system malfunctions, the human has to intervene, but the system can still deny it.

Except in this case it didn't - we're talking about AF447, right? The system gave the pilot full pitch and trim authority via the sidestick through a feature that was specifically designed to give the pilot full authority if something goes wrong with the computers - or if they start receiving bad data. You show me where that A330 did something it was not directly ordered to do and I'll not only shut up for the duration of this thread, I'll personally mail you a cookie.

As far as I can see, Sir, the only one trying to take this thread around into old arguments and logical cul-de-sacs right now is you.

Lonewolf_50
29th Aug 2011, 16:12
HN39Please accept my apologies for misreading your post. I think we also agree that five degrees nose-up is not the optimum response to UAS at FL350.
A simple misunderstanding. :ok: Without your charts I'd not have had anything to work with.
P.S. Rereading your post caused me to wonder what condition would result from pitching up to 5 degrees. I think that in still air the airplane would climb until it is in 1 g level flight with pitch attitude and AoA equal to 5 degrees. Assuming constant total energy, that would be at FL375, 222 kCAS, M=0.7. The stall warning threshold in that condition is 5.7 degrees.
As I understand what you just told me, aerodynamic performance changes (due to the air getting thinner as we go higher) would result in the aircraft transitioning from a climb to a stable, straight and level flight at FL 375 with no other control input (human or computer) than the initial nose up pitch change. (Do you assume constant total energy with or without the engine thrust change from 350 to 375 considered?)

Thanks.

HazelNuts39
29th Aug 2011, 17:05
Lonewolf 50,

I do not have access to a flight simulator or computer simulation. I did no more than define a condition where '1 g' requires an angle of attack of five degrees, and the combination of altitude and airspeed corresponds to the total energy at AP disconnect.

aguadalte
29th Aug 2011, 17:37
Dozzy,

Quote:
The absence of feedback on primary controls seems to be such an error.
Then bring your evidence, as has been asked many times by many people - because right now there doesn't seem to be any.

As a touch-typist and guitarist I'm well aware of how much I rely on muscle memory - surely it must be similar with pilots?

You just brought the answer to your own question. Try to type in a stress environment at the same speed in an AZERTY keyboard than the one you can do on a QWERTY keyboard and see the difference for yourself...
You would have to use your yes and concentration on what you are really typing in order not to commit mistakes. The same for the pilot, that doesn't have the feed-back on the stick. He his deprived from his tactile feed-back and has to look at the PFD to see the results of his commands, therefore loosing a precious useful tool...

Lonewolf_50
29th Aug 2011, 17:41
Thanks HN39, appreciate the work. :cool:

Coagie
29th Aug 2011, 18:38
Jcjeant,
In supporting your argument that authorities may have dragged their feet on finding the wreckage, I point out that one major difference in finding AF447 and the Titanic, lost nuclear subs, needle in a haystack, etc, is that AF447 had a 37.5 khz beacon pinging for 30 days, and the others didn't. The searchers through oversite, incompetence, lack of proper direction, equipment, or personnel, didn't listen for it properly. Chu Chu pointed out that it was reported that the Nuclear sub that listened for the ping, wasn't optimized to 37.5 khz. As a cynical american, I interpret this to mean that they had submariners listening for the ping with headphones, without the 37.5 khz being downconverted to a frequency they could hear. As we know, humans can hear up to 18 khz if they are lucky, and certainly not 37.5 khz . To spell that out, would have drawn ridicule to the investigation, so the euphamism "not optimized to 37.5 khz" was reported. The United States loaned the investigators some proper equipment to listen for the ping that was towed by a tug, but the french were in charge of it, so I don't know what it's search area was or if it was used properly, if used at all.
Anyway, bottom line, there was a beacon to home in on, and they didn't take advantage of it. Sure, some might say, "Maybe the pinger didn't work?". Doubtful. Besides, the first thing the BEA would have done, if the pinger showed failure, when the black boxes were discovered, would have been to shout that fact to the mountain tops, so they'd have a good excuse for what took so long.

DozyWannabe
29th Aug 2011, 18:54
You just brought the answer to your own question. Try to type in a stress environment at the same speed in an AZERTY keyboard than the one you can do on a QWERTY keyboard and see the difference for yourself...

I have, many times, and I know what you're talking about. However, muscle memory is not just about making a movement relative to what is felt, it's about practicing to the point where you instinctively know where to put it in the first place.

You would have to use your yes and concentration on what you are really typing in order not to commit mistakes.

At first, the same way you have to look at the guitar fretboard and/or feel the fret position underneath your fingers to do so at first. But later, as you master it, the muscle memory makes the feedback redundant. You don't need to look or feel where to put your fingers, you just do.

The same for the pilot, that doesn't have the feed-back on the stick. He his deprived from his tactile feed-back and has to look at the PFD to see the results of his commands, therefore loosing a precious useful tool...

Look, I'm not saying (and have never said) tactile feedback is not useful in its place. Trainers should always have as much feedback as possible, because the pilot is learning where to put his hands. Once training for an Airbus FBW type rating, those muscle moves will be practiced in the simulator at first, and then on the aircraft. However, once type-rated and in the aircraft with us SLF down the back, pilots should not have to rely on such "training wheels" to control the aircraft.

Again - I *know* what the theoretical argument is for force-feedback and I acknowledge that. However I still have not seen evidence of a single accident in a FBW Airbus where force-feedback would have helped. In the case of AF447, the PNF *knew* the PF was overcontrolling and he told him not to. Eventually he tried to take over. How would feedback have helped?

Some things that do not seem to be common knowledge about the sidestick arrangement:


Only one pilot is supposed to manipulate the flight controls at any one time by design (most people know that)
Pressing the priority button transfers control from one stick to the other (most people know that)
*Holding down* the priority button prevents the other side from making inputs, or taking priority back
Holding down the priority button *for more than 40 seconds* deactivates the opposite sidestick completely


The PF in the RHS was not a complete rookie, he was a 32-year-old ATPL with an A330 type rating.

RetiredF4
29th Aug 2011, 20:25
First, let me say you have no plan of actual piloting an aircraft. I know, you never said you would have, but you make statements which only flying expierienced pilots can make. Aquadalte has this expierience and flies this type of aircraft if i´m correct, but you don´t listen.

Originally Posted by aguadalte
You just brought the answer to your own question. Try to type in a stress environment at the same speed in an AZERTY keyboard than the one you can do on a QWERTY keyboard and see the difference for yourself...

DozyWannabe
I have, many times, and I know what you're talking about. However, muscle memory is not just about making a movement relative to what is felt, it's about practicing to the point where you instinctively know where to put it in the first place.

Get realistic. Practicing to that point you´dscribe is not going to happen anymore in aviation. That was done 20 years ago and with tactile feedback, now it is without that and especially on long range legs less than 2% of logged flight time. And sim-time will not help either.

Quote aquadalte:
You would have to use your eys and concentration on what you are really typing in order not to commit mistakes.

DozyWannabe
At first, the same way you have to look at the guitar fretboard and/or feel the fret position underneath your fingers to do so at first. But later, as you master it, the muscle memory makes the feedback redundant. You don't need to look or feel where to put your fingers, you just do.

Tell that a neurogist doctor. You are saying, a man with numb fingers can play guitar fretboard like an expert? Since an accident last year i have only limited feeling in my left thumb and first finger. Since then i smashed a plate in average per week by emptying the dishwasher (are not allowes to do it any more). But on the other hand, neither a guitar fretboard nor emtying a dishwasher comen anywhere near the task of flying an aircraft in a situation like AF447 was in.

Quote aquadalte:
The same for the pilot, that doesn't have the feed-back on the stick. He his deprived from his tactile feed-back and has to look at the PFD to see the results of his commands, therefore loosing a precious useful tool...

DozyWannabe
Look, I'm not saying (and have never said) tactile feedback is not useful in its place. Trainers should always have as much feedback as possible, because the pilot is learning where to put his hands.

What kind of statement is that? You are talking about blind school now? Yes i remember, we did a blindfold cockpit checkout, had to operate any switch with blindfolded eyes. Try that with the new systems and pushbuttons...

DozyWannabe
Once training for an Airbus FBW type rating, those muscle moves will be practiced in the simulator at first, and then on the aircraft.

And you know that from wwhom and from what source?
I haven´t done typerating in an airbus simulator, but in the caravelle 20 years ago. But even there it was "procedures and emergencies, using automation as much as possible. You think it is different and there would be time to practice stick handling to the point you imply? Or that would happen in the future?

DozyWannabe
However, once type-rated and in the aircraft with us SLF down the back, pilots should not have to rely on such "training wheels" to control the aircraft.

I would prefer an aircraft with everything available (including tactile feedback) and a crew who can make best use of this aircraft.

DozyWannabe
Again - I *know* what the theoretical argument is for force-feedback and I acknowledge that.

No, you do not. See your next sentence

DozyWannabe
However I still have not seen evidence of a single accident in a FBW Airbus where force-feedback would have helped.

Maybe, that is because in a lot of accidents you can´t talk to the pilots any more. And because in others it is not en vogue to talk about it. And because in a lot of incidents, where tactile feedback was missed there was nobody listening to the crew or a statement from one pilot would have consequences to the other pilot? There are a lot of reasons, even the simplest one, that nobody had an interest to make any statistic evaluation of such a factor.

DozyWannabe
In the case of AF447, the PNF *knew* the PF was overcontrolling and he told him not to. Eventually he tried to take over. How would feedback have helped?

He would have noticed it from the beginning, and he would have seen no improvement after his telling. And he would have taken over like i did as instructor in the backseat of my F4. Take both hands, grip the stick and put it where it is needed. And if necessary take two knees to assist. I could not use JD-EE´s 2-day-old-pizza-tool to get attention, the guy was sitting in front with the instrument panel and gun powder chair in between us. In an A or B cockpit it sure would be an option to get the attention by that or similar attention getters instead silly games like who can push the takeover button first and can press it longer.

Some things that do not seem to be common knowledge about the sidestick arrangement:
Only one pilot is supposed to manipulate the flight controls at any one time by design (most people know that)
Pressing the priority button transfers control from one stick to the other (most people know that)
*Holding down* the priority button prevents the other side from making inputs, or taking priority back
Holding down the priority button *for more than 40 seconds* deactivates the opposite sidestick completely

That should be known by now, and it did not help the PNF at all. I´m not saying that tactile feedback would have helped, therefore we know too little about how much the PNF really was in the loop of the happenings. But if he was, tactile feedback would have helped him and not hindered him.

DozyWannabe
The PF in the RHS was not a complete rookie, he was a 32-year-old ATPL with an A330 type rating.

You are correct, then start thinking what contributed to the fact, that he now looks like a rookie.

I like your technical insight on software and engineering and i apreciate your contributions there. But you are also talking about stuff, which is IMHO totally out of your sandbox. I kept back with this statement for some time and tried to make it clear by other means, but in vain. It is not my task to tell you and if the mods judge this as a personal attack i assure, it is not intended to. But if they like to delete this post, so be it.

aguadalte
29th Aug 2011, 21:24
Trainers should always have as much feedback as possible, because the pilot is learning where to put his hands. Once training for an Airbus FBW type rating, those muscle moves will be practiced in the simulator at first, and then on the aircraft. However, once type-rated and in the aircraft with us SLF down the back, pilots should not have to rely on such "training wheels" to control the aircraft.(My bold)
Look Dozzy,
Its not a question of knowing where to put their hands. Its a question of "feeling" the aircraft responsiveness to the inputs. I understand this is very difficult to explain to non-pilots. But the thing is that when a pilot is flying a non-FBW A/C he his much more "engaged" in the task. If the aircraft is flying faster the stick is harder to move. If by the contrary, the aircraft slows down, the stick is much softer to move. When you accelerate (and if the the throttles move, you have a double feed-back on the response of the aircraft) you feel the "need" to move the stick forward. The opposite is truth for deceleration.

For instance, I don't need to look at the airspeed instrument to "know" the speed of my Pitts. I can look for outside references when practicing aerobatics. The feed-back on the stick gives me the "notion" of the behavior of my aircraft and how much G I can pull. When we (because we are actually 3 owners of that Pitts), first got a sponsor and decided to re-paint our aircraft, it was clear to me, on my first acceptance flight, that the performance of the aircraft had changed, due to the general behavior of the aircraft thereafter, but especially due to the stick feed-back. (We later found out that the painting material used, was not appropriate for wings made of wood and canvas).

On the contrary, I have once taken-off an heavy weighted (252.2 Ton.) A340 that had one spoiler fault. According to MEL not only that spoiler had to be locked but the opposite one had to be locked also. Unfortunately the maintenance left the faulty spoiler unlocked and we took-off a couple of minutes after flight controls check. (when spoilers are fault, we don't get any information of spoiler position - up or down - in the Flight Controls ECAM System Display, only yellow crosses instep of a green spoiler number). We took-off without knowing that right hand spoiler number 6 was out. The behavior of a FBW aircraft is to slightly deploy spoilers on the opposite wing to equilibrate for the down wing moment created in flight. For me, the only impression I got was that the aircraft was "much heavier" than it was supposed to be. If this had happened on an A310 or on a B767, one would had noticed immediately the "need for compensation". When cleaning from flaps 1 to zero, despite of doing it 10kts over S speed, we had an "Alpha Lock" advisory and the climb took us longer than expected also. We have ended up our flight with a consumption of 4 Tons more than expected. This is to say that although no arm came to us due to this event, it took a longer time to understand what was going on. If it happened in a non-FBW aircraft, we would have noticed as soon as airborne.
This are just small issues but that make my case for the need for feed-back on flight controls.
If we can improve, why not do so?
Take care,
I'm flying tomorrow.

DozyWannabe
29th Aug 2011, 22:32
*sigh*

At the end of the day it's all down to personal preference as to whether you think it's important or not. Some do, some do not. Personally I don't give a crap whether the airliner I get on has force-feedback or not, nor - would it appear - do a significant number of pilots. All I care about is that the aircraft has been properly maintained and the pilots know what they're doing. A decent movie on the IFE is a nice bonus. :)

So please stop attacking the messenger here. For every pilot on here that is pro-feedback, there's another one that doesn't miss it. All I'm saying is that as long as there's no empirical evidence, only what individual pilots prefer, then there won't be a case for a design change. Flying a Pitts and an F4 are a world apart from airliner ops, as you well know, and if the worst that happened was a few extra tons of fuel burnt, then that's the airline's problem. How much more do you think would be burned cumulatively by filling the sidestick mounting areas with motors?

And Franzl - I *do* know what you're on about, I may have only flown twenty hours or so in a Chipmunk with an instructor present but I do understand the basics. And for what it's worth, I've had a fair bit of positive feedback from pilots via the PM channel too (I hope they don't mind me alluding to this), so while you're very much entitled to your opinion as to what I should and should not be talking about, please don't take it as a personal insult if I do not stick to my "sandbox".

iceman50
29th Aug 2011, 23:43
RetiredF4

I think you should go back to your sandbox Franzl as you are now getting outside your area of knowledge. Some of us actually fly the A/C involved, have flown Boeing, helicopter, single and multi prop as well as military fast jet experience and do not have a problem with some of Dozy's comments. I have problems with the "luddites", who do not want to get to "know" the technology, just continually moan about it. If you do not know how to operate your A/C you should not be in it.

aguadalte

Unfortunately the maintenance left the faulty spoiler unlocked and we took-off a couple of minutes after flight controls check. (when spoilers are fault, we don't get any information of spoiler position - up or down - in the Flight Controls ECAM System Display, only yellow crosses instep of a green spoiler number). We took-off without knowing that right hand spoiler number 6 was out.

That is :mad: so were you doing your "heavy takeoff" on microsoft flight sim!

After 15+ years on Airbus A330 / A340 the lack feedback on the side stick is not a problem!

CONF iture
30th Aug 2011, 00:21
*Holding down* the priority button prevents the other side from making inputs, or taking priority back
Holding down the priority button *for more than 40 seconds* deactivates the opposite sidestick completely
Negative for #1 - Taking priority back is possible.
Negative for #2 - To reactivate a deactivated sidestick is possible too.

Again, a lot of people who don't like the sidestick design are making that assumption, but if that is the case then why do we have the references to going up when they should be going down and to touch the lateral controls as gently as possible by the PNF?
You have been answered on that question here (http://www.pprune.org/6642575-post2909.html) here (http://www.pprune.org/6643895-post2933.html) and here (http://www.pprune.org/6643878-post2931.html) but don't seem ready to hear.

CONF iture
30th Aug 2011, 00:26
I have problems with the "luddites", who do not want to get to "know" the technology, just continually moan about it. If you do not know how to operate your A/C you should not be in it.
Iceman,
What you do here is to lead a general attack with nothing like an argument. If you're ready to criticize someone, be very specific, otherwise your point has value only in your own eyes.

DozyWannabe
30th Aug 2011, 00:40
Negative for #1 - Taking priority back is possible.
Negative for #2 - To reactivate a deactivated sidestick is possible too.

http://www.smartcockpit.com/data/pdfs/plane/airbus/A320/misc/A320_Flight_Deck_and_Systems_Briefing_For_Pilots.pdf

Page 78.

You have been answered on that question here (http://www.pprune.org/6642575-post2909.html) here (http://www.pprune.org/6643895-post2933.html) and here (http://www.pprune.org/6643878-post2931.html) but don't seem ready to hear.

I corrected my posts to what was actually said, and the only people to argue are those that insist that feedback and connected sticks are a "must have", and were of that opinion before that flight left Rio! I'm still waiting for evidence that lack of connected sticks have caused an accident, and I'm also interested in your reply to the "handling skills" thread.

HarryMann
30th Aug 2011, 01:24
I notice in the Fedex MD-11 Narita landing accident (3 bounces), comments have also been made about leaving the A/P in till 100 ft AGL, possibly contributing to mishandling, especially in rough conditions... once control is finally taken.

Hand-flying down the approach gives a degree of acclimatisation... better SA etc

Being handed back an aircraft at night, in a (somewhat) unknown trim condition, in turbulence, and as we have said many times, is more of problem initially, if out of practice with hand-flight in the cruise... definitely not handled with care and sensitivity commensurate with a 200 ton missile flying at M .8 in thin air, regardless of the 'law'

Why, why, why would a pilot not have even a semblance of sensitivity to feel their way into suitable control inputs...

That sidesticks suits some and not others, IMHO... regardless of the raging controversy about feedback, it wouldn't have happened to that PF with a conventional control column.
Because it would have been seen as absurd, not just by PNF but by PF himself, feeling the forces involved in such gross input at speed and having the thing back in his gut for minutes on end!

DozyWannabe
30th Aug 2011, 01:49
Harry, with all due respect, the PF told the Captain that he'd had the stick against the back stop for a while - this doesn't look like a "I wonder if I should be making inputs this large?" situation, this is a "why aren't these large inputs solving the problem?" situation from the PF's point of view.

As has been pointed out by several others on here, including myself, there are plenty of incidents where a stall was misidentified in an airliner with conventional control column with the same result. I know we would all like to think "No pilot would do that", but sometimes they do.

iceman50
30th Aug 2011, 04:09
CONF iture

In your eyes there is no argument. There is no need to be specific with names as there is a general attack on the Airbus by a majority who have never even flown it. They want to return to the 1950's, well it is not going to happen, learn the new ways and remember we are PILOTS we FLY the A/C either manually or through the A/C systems!

Do YOU fly Airbus?

hetfield
30th Aug 2011, 09:50
World's 10 safest airlines (in alphabetical order)
Air France-KLM
AMR Corporation (American Airlines, American Eagles)
British Airways
Continental Airlines
Delta Airlines
Japan Airlines
Lufthansa
Southwest Airlines
United Airlines
US Airways
World's top 10 safest airlines named | Air Transport Rating Agency (http://www.smh.com.au/travel/travel-news/worlds-top-10-safest-airlines-named-20110830-1jj3k.html?from=smh_sb)

So 4 hull losses at AF - no problem:ugh:

CONF iture
30th Aug 2011, 10:44
iceman,

No need to be specific with names, but technical stuff.
Answering the technical stuff concerns will be good enough.
No one here has pretended to go back to the 50’s but remember how technology should be reserved at serving human, not the opposite.
More computers for more automation is not a solution, keeping things simple is, IMO.
Airbus would be much better with less complexity.

I DO … but even if I didn’t I could positively develop an argumentation as long as I don’t pretend explaining to others including former or current technicians and pilots how things work, and so using unofficial documentation : Dozy, SmartCockpit (http://www.smartcockpit.com/) is an excellent site but is what it is and has never pretended to propose more :

http://i45.servimg.com/u/f45/11/75/17/84/af447_16.png (http://www.servimg.com/image_preview.php?i=110&u=11751784)

Rananim
30th Aug 2011, 10:48
Pilots have changed.I recognize nothing familiar in the new breed.I see kids with blackberrys and ipads that never cuss.Its a whole new "profession" and I am now an outsider.Im displaced.
-The pilot that once was would never have accepted to fly in an aircraft with such piss-poor pilot involvement.Its frankly as if the designer has said ":mad: You,you dont count,sit there and shut up"
-The pilot that once was would NEVER EVER have accepted to have the computer move the THS.Its a great big flt control surface and you want the computer moving it to its aerodynamic limit insidiously and during abnormals.Talk to the dead crew of Perpignan/Nagoya.Ask the TAROM/INTERFLUG/CAL/FINNAIR crew about how they feel about fighting for pitch control of their aircraft with a malcontent computer.
-The pilot that once was would never have put up with anything but a central stick with FULL TACTILE FEEDBACK and thrust levers that :mad: move.The Airbus SS disconnects the pilot from the machine(ADI is sole feedback) and also the pilots from each other.Mr Caesar was quite right.Why did the PNF of 447 intervene so late?He appears to have recognized that the wrong stall recovery procedure was being flown,yet did nothing until it was too late?Why couldnt the Captain see a clear picture when he returned to the flt deck?Because the plane told him very little.No visible stick.No shaker.Not even a stall warning.He was the Captain and he was rendered helpless!Imagine someone inventing a plane that can remain in a DEEP STALL with no warning to the pilot.NUTS.
-The pilot that once was would never have let automation dependency cripple his manual flying skills.Pride in one's own ability to fly the plane..where has it gone?Today,its click click at 500' and fly the last minute of the ILS with the dual cue FD.A video game.And thats what the airlines want and certainly what the AIrbus is designed for.Do the pilots of today utter one word of objection and bring their concerns to management?Pilots used to be in mangement,now theyre not.Maybe thats one reason.

I think I see now how we've got to this sorry state.It was the pilots all along.The pilots have got what they deserve.Rugged independence replaced by meek submission.Military replaced by civilian.Pilot replaced by flight manager.It started with the introduction of CRM and picked up speed with the arrival of Airbus in the mid 80's.I see the new order in spades on this forum from the likes of safety concerns and iceman who hail the brave new world as the conquering hero.Political correctness out of control with de-unionized pilots paying to fly and at the mercy of some omnipotent HAL in the cockpit.

"I'm sorry Dave but I cant let you do that...."

It came true.Go figure.

iceman50
30th Aug 2011, 11:06
aguadalte

For me, the only impression I got was that the aircraft was "much heavier" than it was supposed to be. If this had happened on an A310 or on a B767, one would had noticed immediately the "need for compensation". When cleaning from flaps 1 to zero, despite of doing it 10kts over S speed, we had an "Alpha Lock" advisory and the climb took us longer than expected also. We have ended up our flight with a consumption of 4 Tons more than expected.To further expand on my short reply before, I suggest you had your figures way wrong for the take off or retracted them too early, as to get an Alpha Lock you must have been below 154kts and at 252 tonnes I think your S speed would have been a LOT higher than 144kts!!!


SLATS ALPHA / SPEED LOCK FUNCTION
This function inhibits slats retraction at high angle-of-attack and/or at low speed. The SFCCs use a corrected angle-of-attack (alpha), or air speed information from the ADIRUs to inhibit slat retraction.
If alpha exceeds 8.5 degrees, or the speed falls below 148 knots, the retraction from position 1 to 0 is inhibited.
The inhibition is removed when alpha falls below 7.5 degrees, or when the speed exceeds 154 knots. In this case, the slats automatically retract to 0.
The function is not active if:
— Alpha exceeds the above values after the lever has been set to 0.
— Aircraft is on the ground, with the speed below 60 knots.CONF / Dozy

The reference for the sidestick priority

Sidestick priority logic
— When only one pilot operates the sidestick his demand is sent to the computers.
— When the other pilot operates his sidestick in the same or opposite direction both pilots inputs are algebraically added. The addition is limited to single stick maximum deflection.
Note : In the event of simultaneous input on both sidesticks (2° deflection off the neutral position in any direction) the two green SIDE STICK PRIORITY lights on the glareshield come on. In addition on A330E, the "DUAL INPUT" voice message activates).
A pilot can deactivate the other stick and take full control by pressing and keeping pressed his takeover pushbutton.
For latching the priority condition, it is recommended to press the takeover pushbutton for more than 40 seconds. The takeover pushbutton can then be released without losing priority.
However, at any time, a deactivated stick can be reactivated by momentarily pressing either takeover pushbutton. If both pilots press their takeover push buttons, the last pilot to press will get the priority.
Note : If an autopilot is engaged, the first action on a take over pushbutton will disengage it.I think the only way to keep the stick deactivated would be to NOT release the button after the 40 seconds!

hetfield
30th Aug 2011, 11:14
Rugged independence replaced by meek submission.Military replaced by civilian.Pilot replaced by flight manager.It started with the introduction of CRM ..Sorry, but is wrong with CRM, what is wrong "civilian" (Pilots)?

SLFinAZ
30th Aug 2011, 13:15
Unfortunately the real issue here is nothing other then an unqualified pilot put in the wrong place at the wrong time and a cockpit culture that prevented the more qualified PNF from immediately taking control of the situation.

At the end of the day this is not a SS vs yoke, A vs B or even an "automation" issue. In fact this appears to be one time that the automation actually worked correctly...handing off the plane to the pilot in a relatively stable configuration due to conflicting data. In effect as soon as the AP computers recognized "garbage in" they kicked the plane back to the PF in order to avoid "garbage out".

Sadly the "garbage out" was provided by the PF.....

GarageYears
30th Aug 2011, 13:27
According to the Wiki (slam it if you will) there are something like 5100 odd Airbus aircraft in service, of which in excess of 90% will be FBW using the 'standard' side-stick controller...

In the last 10 years Airbus has sold more aircraft than Boeing in 8 of those years...

Is the SS intrinsically flawed? Empirical evidence states not so. Accident figures do not support this. Academic study does not support this (NASA). What does support this? Evidentially not a lot, except an excess of hot air.

Artificial feel - there is not one single single or dual-aisle passenger aircraft that has anything other than power assisted controls - meaning what is felt through the control column has nothing other than some engineers idea as to the true control loading. Does that mean a control column has more connection to the control surfaces, versus a side-stick? I vote - No. It is simply different. The Airbus loading is spring-induced.

Left-seat/right-seat - pretty much everyone reading this post has a mouse sitting just to the right of their keyboard I'd bet. Switch the mouse to the left-side and leave it there for the rest of the day. For the first few minutes things are a little 'confused' - 4 hours later it will feel normal.

A lot of the discussion here seems to be reaching for some reasoning, beyond the evidence. The PF over-reacted at AP/AT drop, drove the aircraft into a stall, and then missed the recovery, with a fixation on pulling out of the fall, rather than flying out of the stall. Did the PNF understand the situation? Maybe, but whatever his convictions were, they were not definite enough to take command. Did the call-back of the captain help? No. Did it make any difference? No. Was this a sign that the PNF was not sufficiently confident - yes. Did this situation become one of "too many cooks? Perhaps so.

HarryMann
30th Aug 2011, 14:24
Too many cooks? Yes, can agree to that...

Wouldn't it be acceptable for the Captain when he sensed a loss of control, to immediately re-take his seat and see for himself, rather than obtusely peering over or between them and still missing the vital clue.

Or is this a definite no-no... sorry not acquainted with cockpit protocol (apart from the the 2-day old pizza swipe)

this doesn't look like a "I wonder if I should be making inputs this large?" situation, this is a "why aren't these large inputs solving the problem?" situation from the PF's point of view.

OK then, if true, so back to PNF (and then the Captain) seeing 'stick permanently in groin' and grabbing his collar, or looking for an old pizza

I know Airbus will persist, and in principle I am not against -some form of sidestick - but you must not remove its poor relationship to the human frame as a primary control, nor the columns inherent benefits (which are inarguable and proven) from the argument.. That is fact - the feedback to one and all - without additional instrument scan and mental clutter - is INCONTROVERTIBLE.

In this accident, this Sidestick did not do its proponents any favours... please do not argue aginst such an obvious conclusion

BOAC
30th Aug 2011, 15:14
nothing other then an unqualified pilot put in the wrong place at the wrong time - unfortunately that is incorrect. Both pilots were 'Qualified' and in the 'right place' at the 'right time'. Where you need to place the blame is on the nature of the 'qualification' and whether they had the tools to do the job.

deSitter
30th Aug 2011, 15:19
It is impossible for anyone doing anything from welding to cryptography to perform when his boss, or some other authority figure, is peering over his shoulder. My friend who is a teacher has to deal with "observations" by administration in the new regime at his school. He says this throws him completely off his game and makes it nearly impossible to perform.

Yes, the captain standing there observing while the plane plummeted, must be counted as the person most responsible here, both for failing to take charge and fulfill his duties as commander of his craft, as well as failing as a pilot.

Good memories
30th Aug 2011, 15:58
- unfortunately that is incorrect. Both pilots were 'Qualified' and in the 'right place' at the 'right time'. Where you need to place the blame is on the nature of the 'qualification' and whether they had the tools to do the job.

Too many pilots here put the blame far too early in the investigation on the crew. Let's first do the test on the aircraft with the same figures and see how easy it is to get her out of this stall. Line pilots, test pilots, 500 hrs and 20.000 hrs. No simulators please.

Only then we really know what happened there and why they did not recover from that stall.

BOAC
30th Aug 2011, 16:14
GM - thanks for the support but you will, I'm afraid, be hounded out of town by the baying mob for the rest. It is quite obvious why they did not recover from the stall. How they got to it is less easily explained.

Safety Concerns
30th Aug 2011, 17:04
AF447 stalled. It was an all singing, all dancing, digital aircraft. One of the pilots maintained full pitch up for quite some time obviously unaware that he had stalled.

NW6231 stalled. It was an old fashioned, bells and buzzers aircraft with very visible yoke feedback. One of the pilots maintained full pitch up for quite some time obviously unaware that he had stalled.

What the **** has this to do with any particular manufacturer.

jcjeant
30th Aug 2011, 20:30
Hi,

What the **** has this to do with any particular manufacturer. Nothing of course
Only the pilots are involved in this accident
Cause they were qualified to fly this type of plane at high altitude with no speed indications but failed ..
They will be the first culprits shown in the trial result .. the role of Air France and Airbus and official bodies will be seen as very minor in this accident.
Why ?
You can not blame Air France for not quickly replace the pitot tubes
There were no laws that mandatory a substitute .. only non-binding recommendations
You can not blame Air France not to properly train pilots .. because they will prove that they scrupulously follow the laws of formation and training
You can not accuse Airbus .. because their systems and aircrafts have been certified by official bodies and they have given the green light for the commercial operations of Airbus
So .. who is guilty in a legal standpoint?
The three pilots (the crude reality)
Well sure .. Air France will be responsible for the payment of damages and other expenses of the victims' families (the Vienna and Montreal conventions .. etc. .. will apply)
And you can't not involve the official bodies .. etc .. as they are state entities ... (never culprit)
And it will be just some (more) recommendations from the BEA for satisfy anyone ....

ChristiaanJ
30th Aug 2011, 22:04
....Let's first do the test on the aircraft with the same figures and see how easy it is to get her out of this stall. Line pilots, test pilots, 500 hrs and 20.000 hrs. No simulators please.Roger, wilco and out.
It's still an open question whether the A330 was ever taken well into a full stall during flight testing and certification, or whether they just 'nibbled at the edges of the envelope'.
That answers your "no simulators please" remark as well....
'Nibbling at the edges' does not provide useful data for behaviour in a full stall, and extrapolating those 'nibbles at the edges' does not make for a useful behaviour of the sim.

DozyWannabe
30th Aug 2011, 22:41
@GM, CJ :

I think the natural response from test pilots to that suggestion would be "sure, as long as you and the person that made the calculations for the maximum possible escape altitude and velocities were on the jumpseats".

NeoFit
30th Aug 2011, 22:50
Let's first do the test on the aircraft with the same figures and see how easy it is to get her out of this stall

It seems to me that this test has been conducted.

The only way to get out of stall was engine iddle

grizzled
31st Aug 2011, 01:32
Rananim...

Thanks for the superb rant! :D

Words and notions that make us chuckle often do so because they create a mental caricature of a truth. That is to say, slightly distorted but certainly not wrong.

Re: It came true. Go figure. Despite all the head nodding and confidence regarding current Safety Management philosophy, and the "proactive" or "predictive" methodologies espoused, we as humans are very poor at foreseeing some of the most likely long-term outcomes of things we do and changes we make.


'Twas ever thus...

BOAC
31st Aug 2011, 07:38
Dear oh dear - this is certainly going the way of all threads on this now diminished site.

Rather than all chase after shadows of '5 degrees is not right' and 'recovery from that sort of stall needs to be tested', let's remind ourselves that the setting of ANY pitch attitude is a temporary measure followed by 'levelling off' (if appropriate) and applying the QRH, AND that it is pretty widely accepted, I think, that had sufficient forward stick been applied the nose would have lowered and the aircraft would have been unstalled.

If anyone can find a contradiction to both of those, please post a reference or can we get on with useful discussion now?

RetiredF4
31st Aug 2011, 08:23
ChristiaanJ
Roger, wilco and out.
It's still an open question whether the A330 was ever taken well into a full stall during flight testing and certification, or whether they just 'nibbled at the edges of the envelope'.
That answers your "no simulators please" remark as well....
'Nibbling at the edges' does not provide useful data for behaviour in a full stall, and extrapolating those 'nibbles at the edges' does not make for a useful behaviour of the sim.

The values for the A310 are available.

Upset recovery training (http://www.mediafire.com/?jrkvp2ysl7aea25)

Load down the referenced zip, there are tested envelopes for a lot of common air transport aircraft.

Bolding by me
There are issues associated with differences between simulator training and aircraft recoveries. A simulator can provide the basic fundamentals for upset recovery, but some realities such as positive or negative g’s, startle factor, and environmental conditions are difficult or impossible to replicate. These limitations in simulation add a degree of complexity to recovery from an actual aircraft upset because the encounter can be significantly different from that experienced during simulator training. Therefore memory checklists or procedural responses performed in training may not be repeatable during an actual upset situation. The limitations of simulators at the edges of the flight envelope can also cause fidelity issues because the simulator recovery may or may not have the same response characteristics as the aircraft being flown. However, provided the alpha and beta limits are not exceeded, the initial option responses and instrument indications of the simulator should replicate airplane responses.

The Alpha and Beta values are depicted in Appendix 3 for a lot of aircraft, from AB the A300/A310.
In short with flaps up flight validated from 0° AOA up to 12 AOA,
Wind tunnel / analythical from -5°AOA up to 12 ° AOA
Extrapolated for simulator from -5° AOA up to 30° AOA


What would us make believe, that for A320 / A330 the envelope was expanded despite better protections?

jcjeant
31st Aug 2011, 08:49
AP IMPACT: Automation in the air dulls pilot skill - Yahoo! News (http://news.yahoo.com/ap-impact-automation-air-dulls-pilot-skill-070507795.html)

Jazz Hands
31st Aug 2011, 09:23
After Spanair it's become clear to me that pilot unions want their cake and eat it - they want automation to catch their errors, but then want to blame the same automation for their reduction in situational awareness.

There's no such thing as "automation dependence" if a pilot is aware what his aeroplane is doing, and doesn't get complacent about it. Maybe that's the real issue.

aguadalte
31st Aug 2011, 10:09
IMG_0164 | Flickr - Photo Sharing! (http://www.flickr.com/photos/67056637@N08/6099065777/in/photostream)

iceman50,
I am not a liar. See the picture taken after-landing, with HYDs de-pressurized.
I don't know if you are a pilot, but I am sure you're also a pen-pusher. You know all the :mad: numbers by heart.
Somebody here defined very well that sort of guys, many moons ago.
An aircraft taking-off with a spoiler out will need more attitude (and AoA) to compensate for the lost Lift, especially when crossing the 200kts automatic flap up sequence.
Does it ring a bell?
(No, I didn't clean-up before S Speed. Yes we did have a blinkering Alpha Lock during slat/flap retraction.)

Now I understand why you don't care about stick feedback...
(...but I really don't care. I'm tired of this stupid argumentation. You didn't even care to notice the safety design issue here, of a system that may blow out a substantial part of your performance "camouflaged" by the FBW. Your approach was to, first, denigrate the aviator before he wins any point with his story. So be it. Stick with your beliefs. I'll stick with mine).

AlphaZuluRomeo
31st Aug 2011, 10:54
It seems to me that this test has been conducted.

The only way to get out of stall was engine iddle

Mhmm... one source, a union. Known for its "all means good to fit our agenda" methods (no they don't kill, but when it comes to declare something...)
No confirmation so far.
I would wait a bit more before believing that, if I were you.:)

J.O.
31st Aug 2011, 12:23
Only the desperate would try to turn an incident caused by a maintenance error into an excuse to blame the manufacturer for a bad design. That's like saying it was MD's fault that the engine fell off of the DC-10 at Chicago, even though it was American Airlines that did improper engine changes. :ugh:

ChristiaanJ
31st Aug 2011, 13:09
RetiredF4,
Thanks for the 'zip' link !
I've downloaded it, but it's over a hundred pages, so I still have to read it ...
I did see the alpha-beta plots... even more extrapolation than I expected.

Good memories
31st Aug 2011, 13:38
It seems to me that this test has been conducted.
The only way to get out of stall was engine idle

Hi Neofit,

Do you have any more information on the stall tests you can share with us?

SLFinAZ
31st Aug 2011, 21:07
I have seen no report indicating that the plane was handed off in an unstable or stalled condition. The plane was slightly nose down and slightly banked at AP disconnect. The airframe was flown into a stall entirely due to the actions of the PF.

iceman50
1st Sep 2011, 00:02
aguadalte (http://www.pprune.org/members/154623-aguadalte)

Yes I am an A340/A330 Captain like you! If you want to call me a "pen pusher" because I try to know my A/C so be it. I would have expected the same professionalism from you.

You claim this incident occurred when flap was selected from 1 to 0, on a heavy A340 10 kts above S speed and now you are trying to say
especially when crossing the 200kts automatic flap up sequence.
Does it ring a bell? so which was it auto flap retract or your selection of Flap 0. The Aplha Lock function is for SLAT retraction not FLAP and again I doubt S speed would have been as low as 190kts at 252 tonnes, for you to be 10 kts above it.
You also claimed that you cannot see if the spoilers operate, that is incorrect as you can see that on the Flight control page when you carry out the flight control checks.
But there again you have said that you need tactile feedback.

As the A/C commander you are required to know your A/C. Blaming maintenance action and then FBW for hiding something, amazing. Did you not wonder why you had the Alpha Lock and investigate?

bubbers44
1st Sep 2011, 02:29
As SLF said the plane if left untouched would have probably flown out of the short UAS problem fine. The PF did all the wrong things no professional pilot would do and put it into a full stall. This has been repeated so many times on this thread. How many pilots do you know would do what he did? Of my hundreds of fellow pilots, zero. However they all knew how to handfly an airplane at any altitude safely.

SLFinAZ
1st Sep 2011, 04:26
Actually yes, if we divide the aviation world into its fundamental break point....those who have soloed and those who haven't. What I find so absolutely perplexing is actions so fundamentally incorrect that even a student pilot wouldn't make them.

TJHarwood
1st Sep 2011, 04:41
The Welsh Wingman is on holiday with his grandchildren in Florida, but I doubt that he would have any idea what "Indie" music is (I had to ask!).

Please remember that, whilst he tries to contribute in as widely accessible language as possible, he comes from a very different world/era to you (and so do I!).

This is where he learnt his airmanship, deck landing 45 year ago on carriers that were "so large" (!) that one or two may have carried Swordfish FAA squadrons when initially commissioned into the Royal Navy a generation earlier.

Pilot's Cockpit Layout - Buccaneer S.Mk.2B (http://www.blackburn-buccaneer.co.uk/Pages1_files/Technical_files/Tech6_files/0_Cockpit.html)

No pretty glass cockpit or even pretty AoA indicators, whether standard or optional, but instead AoA trained on audio ADD (cross-referenced to ASI/AUW) whilst optically focussed on the carrier centre-line.

I flew with him, years later with the same airline, both as a F/O (and later as a Captain in the RHS, oh how times have changed...) in the RHS of several B741s.

The point he is making in relation to "feedback" and yoke v (dead) SS is relevant because, as I have previously discussed with him via PM, it relates to the pivotal question of what inhibited the more experienced (if not PIC) PNF from taking control of the aircraft no later than 2H 10 31. It may have made no difference, but we definitely know the consequences of his not doing so (even if the CDB had rectified the position after 2H 11 43, it was by that stage well beyond "a logbook entry" and outside of safe flight ...). Did the absence of a clearly visible yoke in front of the PF or SS interconnected feedback to the LHS SS make a difference to the PNF, or was it all in his DNA/training?

It may be that a visible RHS yoke and interconnected LHS SS, unambiguously visibly spelling out the PF's commands, may have made no difference to the PNF's actions/omissions whatsoever, but the question has to be asked in the context of AF447 and the CRM/cockpit discipline issues that are under scrutiny. I think it was the Welsh Wingman who first drew attention to Stony Point in these threads, so he has never suggested that it is the panacea for all ills (even without more recent "yoke" repetition with Colgan Air and West Caribbean) and he has no "agenda" to pursue.

Trust this clarifies? I suggest you PM him regarding these issues.

TJHarwood
1st Sep 2011, 04:59
Sorry for delayed reply.

I could not agree more, particularly with your following paragraph:

"I think that is what was meant when someone else here said that automation was an assistant to the pilot; it is most certainly not a third or fourth pilot but as that dangerous mentality gets even more established, especially with managements and pilots who have flown nothing but automated aircraft, the way back becomes very difficult because fear builds upon fear and soon one is afraid to fly. Seen it, and I doubt very much whether this was ever the original intent of those who contemplated using microprocessors to solve the problems of flight."

The erroneous perception of automation seems to seep into airline cultures, training and SOPs, and I hope the "human factors" experts do not duck their challenge and spell it out.

For all the improvements in safety, particularly in relation to collisions and CFIT (as you say), I would be surprised if this incident (a temporary UAS issue) would have brought down an airliner 25 years ago in the same conditions (whether Concorde/A300/TriStar/DC10/B747, to cover the then range of major manufacturers).

Why it is so frustrating......

TJHarwood
1st Sep 2011, 06:01
"Only the desperate would try to turn an incident caused by a maintenance error into an excuse to blame the manufacturer for a bad design. That's like saying it was MD's fault that the engine fell off of the DC-10 at Chicago, even though it was American Airlines that did improper engine changes. :ugh:"

It was both, of course, re: AA191.

Redundancy in the power to the LHS stick shaker and the RHS stick shaker not being optional, to overcome both design flaws (in addition to no leading edge slats lock), would likely have broken the chain of causation (irrespective of the AA maintenance misbehaviour that caused the engine separation).

Always a chain of causation.......

DozyWannabe
1st Sep 2011, 11:06
For all the improvements in safety, particularly in relation to collisions and CFIT (as you say), I would be surprised if this incident (a temporary UAS issue) would have brought down an airliner 25 years ago in the same conditions (whether Concorde/A300/TriStar/DC10/B747, to cover the then range of major manufacturers).

As you said, it brought down a 727 42 years ago or so - remember that all the designs you list went into service around 40 years ago. 25 years ago, the TriStar and DC-10 were being replaced by B767s and MD-11s. (And yes, that even makes me, who knows what "Indie" music is, feel old! I don't think I intended to direct that comment at WW, by the way, I think I just threw it out there apropos of nothing).

The West Caribbean MD-80 was an older airframe design with newer avionics. It amuses me that a lot of the Airbus bashers don't seem to be aware that an old design, with yokes, stalled into the ground from cruise altitude, and not only that - unlike the Airbus, the autopilot *did* play a part in trimming the airframe towards the stall, although in that case it was due to being overweight (with engine anti-ice on). Also in that case, the PNF noticed they were in a stall, said so to the Captain and was roundly ignored - possibly because the Captain had become fixated on the EPR gauges and assumed a flameout. Also in that case, the Captain (who failed to recognise the stall), also spent the entire descent hauling back on the control column (which again, the PNF could see, but did not feel able to do anything other than give advice). This Captain was no rookie, but it was alleged that because of West Caribbean's financial problems (a result of which was that the pilots had not been paid for 6 months(!)), he had been forced to take on a second job as a bartender and this probably affected his ability to take the required rest.

aguadalte
2nd Sep 2011, 00:12
iceman50:
Yes I am an A340/A330 Captain like you! If you want to call me a "pen pusher" because I try to know my A/C so be it. I would have expected the same professionalism from you.

Well, if you knew your aircraft, you would know that when spoilers are blocked (and de-activated) you have no way to see them moving on the flight controls check. (You will have amber crosses in step of spoiler numbers nor will have the movement arrows...)
Further, next time you go to your flight sim session ask your TRI/TRE to offer you a take-off on the said conditions (if he can duplicate it, because second to AI this is something that was not supposed to happen...) and pay attention to the attitude of the aircraft while you clean up. I just came today from EWR and took-off with "only" 218Tons and during flap retraction it was easy to see a >10º up ATT while crossing the 200kt automatic flap retraction. Now imagine your aircraft doing it with the increased drag of an open spoiler plus FBW compensation on opposite wing.
All I can say is that it was a combination of factors during slat/flap retraction, and I have learned from that. Because of your disbelieve, I have located my CR and ASR of that flight and I have nothing to change to my first post.
icemen50, we're drifting out of this thread, and I really don't think we're going anywhere. You may believe what I said, or not. I really don't care...it want make it change what happened...

iceman50
2nd Sep 2011, 03:36
aguadalte

As you have said this is drifting of topic so we shall agree to disagree.

Safety Concerns
2nd Sep 2011, 10:55
I know aguadalte is both a captain and a gentleman. I do not know iceman so can't comment.

However it seems that this little spat highlights the real issue. Too many Pilots are not in tune with their aircraft, they only think they are. You can't both be right.

grimmrad
2nd Sep 2011, 15:09
see the last 3 post - which is kind of frightening from the perspective of a SLF!

ap08
2nd Sep 2011, 16:13
see the last 3 post - which is kind of frightening from the perspective of a SLF!
Don't worry. Things may not be as bad as they look. Many people who pretend to be pilots, in fact only fly the microsoft flight simulator, and this forum is no exception.

CONF iture
2nd Sep 2011, 17:10
Too many Pilots are not in tune with their aircraft, they only think they are.
Despite best intentions, it is increasingly difficult to know and understand everything as information is minimal and softwares discreetly modified.

After a serious event like Hamburg you learn that the manufacturer did not consider as necessary to advise the pilots that after a brief rebound on one main gear, only half deflection of the control surfaces will be available, which means that the very next second the airplane will respond in a very different way to the same sidestick input.

Lyman
2nd Sep 2011, 17:17
Along those lines per rudderrat and CONFiture.

The a/c experienced a VS (UP) of 1000 fpm, with the Nose PITCHED down between 3-4 degrees off cruise, just three seconds prior to releasing AutoFlight.

So let us relinquish the slander of "Had he only kept hands OFF"....etc.

The airframe required handling, stop.

Pursuant "surprise" responses, as above from CONFiture, a quick disconnect in that ambient would have most of the pseudo sticks here p-ing their pants.

Some perspective at least, if Respect is impossible.

Puravida's excellent graph shows "What's that?" (PNF) occurring prior to the STALLSTALL.....Any responses from the current crop of detective?

oldchina
2nd Sep 2011, 19:39
According to the CVR transcript, the STALL STALL occured before the
"Qu’est-ce que c’est que ça?" ... What's that?
You disagree?

Lyman
2nd Sep 2011, 22:26
oldchina. I have no opinion. BEA reported STALL, then .6 seconds later, "What's that?" Tight timing for an exclamation of "What's that?" if only related to STALL WARN.

Have you considered the exclamation may be in response to BUFFET?

That would mean the PNF reacts to BUFFET, then STALLWARN sounds, (w/o cricket).

My point is that puravida has the exclamation prior to SV STALL.....

Of course the best, but still inconclusive, is that the exclamation post dates the STALL, but without excluding the possibility he was reacting to BUFFET, or some other artifact on the CVR.

BEA will do what they have to do, but without a complete, fully transcribed and indexed CVR, whatever conclusion they publish will not be ironclad, v/v the CVR.

There is an additional possibility from the French:

"What is that?.......THAT!!" As if he may be pointing to something and for emphasis, "SEE, THIS!"....... Or, he may be pointing to his ear, ("you hear?") etc......

I'd be wary of jumping to conclusions, of course.

Turbine D
2nd Sep 2011, 23:30
Lyman

See that you are back!

From the BEA Interim Report #3:
The bold depicted is my addition.

At 2 h 10 min 05, the sudden drop in the measured airspeeds, likely due to the obstruction of the Pitot probes by ice crystals, caused autopilot and autothrust disconnection (the thrust was then locked) and the change in the flight control law from normal to alternate. The presence of turbulence, shown by the inputs by the AP to control the roll in the previous seconds, led on disconnection to the airplane beginning a roll to the right of up to about 8°.
The PF copilot said “I have the controls” and made rapid and high amplitude lateral, almost stop to stop, inputs. He also made a nose-up input that increased the airplane’s pitch attitude up to 11° in ten seconds. The Flight Directors were not disengaged by the crew, but the crossbars disappeared.
At 2 h 10 min 10, the PF’s nose-up inputs increased the angle of attack and the stall warning triggered twice transitorily. Probably in reaction to this warning, the PNF exclaimed “what is that?”. The PF then said “We haven’t got good ... We haven’t got a good display ... of speed” and the PNF “We’ve lost the speeds”. The angle of attack recorded was around 5°, for a theoretical stall warning threshold trigger value of slightly over 4°.
The crew identified the loss of the speed displays but neither of the two copilots called out the associated procedure. The “Unreliable IAS” emergency manoeuvre requires as a first step to disconnect the automatic flight controls and disengage the Flight Directors. The two copilots had only been trained for the emergency manoeuvre at lower levels, in the course of which the pitch attitude to adopt is 10° or 15°.
However, an OSV note described the problems of the loss of speed indications up to then on the A330/A340 fleet in cruise and recalled the procedures to apply. This note had been distributed to all the flight crew in the A330/A340 division.
Between 2 h 10 min 18 and 2 h 10 min 25, the PNF read the ECAM messages in a disordered way but mentioned the loss of autothrust and the change to alternate law. The thrust lock function was de-activated. The PNF called out and triggered the wing anti-icing.
The PNF then drew the PF’s attention to the speed. At that moment, the two recorded speeds (the one displayed on the left on the PFD and that on the ISIS) were below 100 kt and the vertical speed reached a maximum of 7,000 ft/min. The airplane’s longitudinal movements resulted from the inputs by the PF, who in addition continued to make high amplitude lateral inputs to control the roll, below 10° to the right and to the left.
Reading the three instruments (the two PFD’s and the ISIS), the PNF noticed that the airplane was climbing and asked the PF several times to descend. The latter then made several nose-down inputs that resulted in a reduction in the pitch attitude and the vertical speed, whose values nevertheless still remained excessive; the airplane then being near 37,000 ft and continuing to climb, without any intervention from the PNF. Although the REC MAX had been a permanent preoccupation before the AP disconnection, neither of the two copilots made any reference to it.
At around 2 h 10 min 34, the speed displayed on the left side became valid again and was then 215 kt; the speed on the ISIS was still incorrect. The airplane had then lost about 60 kt since the autopilot disconnection and the beginning of the climb, which is consistent with the increase in altitude of around 2,000 ft.

Now from your post:
Have you considered the exclamation may be in response to BUFFET?

That would mean the PNF reacts to BUFFET, then STALLWARN sounds, (w/o cricket).

My point is that puravida has the exclamation prior to SV STALL.....

Of course the best, but still inconclusive, is that the exclamation post dates the STALL, but without excluding the possibility he was reacting to BUFFET, or some other artifact on the CVR.

BEA will do what they have to do, but without a complete, fully transcribed and indexed CVR, whatever conclusion they publish will not be ironclad, v/v the CVR.

There is an additional possibility from the French:

"What is that?.......THAT!!" As if he may be pointing to something and for emphasis, "SEE, THIS!"....... Or, he may be pointing to his ear, ("you hear?") etc......

Now, if one believes in reincarnation, I would think you were a very good defense lawyer in your prior life. The points you raise and the questions you ask are very typical of that a defense lawyer would pose to a jury to hopefully instill doubt or confusion to facts presented during the proceedings. The BEA is giving the pilots some slack by mentioning their lack of formal training at high speeds and altitudes and left some room at this point as to the "What was that?" comment by the use of the word "probably". But, they have the tapes, the recorded verbal exchanges and the verbal timing sequences to other recorded data. If these details don't come out in the final report, it will in the legal process as all the data belongs to the French Legal Organization.

As to the technical aspects of the actual airplane, that is something to be debated by the Airbus pilots and Airbus, the manufacturer. Hopefully this debate will lead to smart, well thought out improvements to bring flight safety to a higher level. When you think of the number of commercial aircraft, all makes and models, in the air at any given time, 24, 7, 365, the safety is really very good, but there is always room to improve as it is not 100%, but not far off.

goldfish85
3rd Sep 2011, 00:11
Garageyears

Left-seat/right-seat - pretty much everyone reading this post has a mouse sitting just to the right of their keyboard I'd bet. Switch the mouse to the left-side and leave it there for the rest of the day. For the first few minutes things are a little 'confused' - 4 hours later it will feel normal.

Not everyone. I'm left hnaded, but have extreme difficulty using the mouse/trackball/touchpad with my left hand. In 50 years of flying, I've never had problems with a yoke or sidestick from either seat. Go figure.

Lyman
3rd Sep 2011, 00:43
TD Howdy.

Pointed questions generally have a point, that is true, but the ones I write down are as consistent with a round table discussion of accident reconstruction as with a courtroom drama.

The Pilots are not charged, so your opinion that they represent a 'defense' are thus far off the mark.

As I have posted here before, the latitude you point out re: the 'Pilots' inures more to the Airline than to the crew.

Latitude by Proxy, then? One cannot "protect the crew" without hiding the Line's culpability. Is this conscious? Ever the sceptic, my answer is YES.

They HIRE, They FIRE, and hopefully, they TRAIN. Taken at face value, one is hard pressed to establish any conclusion at this point that does not roundly condemn the Airline. As it should be.

Foot dragging on the Probes, lack of high altitude APPROACH TO STALL recovery, and a very apparent lack of training in automatic handoff with LAW degrade at CRUISE. Let's be generous to the 'crew' and also include a lack of training in recognition of OVERSPEED (or its LACK).

Pressuring for a 'quieting' of the discussion defeats what is gained by having an internet in the first place. The very point of having the freedom to discuss is a commandment to use it.

take care

bubbers44
3rd Sep 2011, 00:46
Does anybody here believe the PF was not at fault by pulling the SS full up for 3 minutes until impact with the ocean?

bubbers44
3rd Sep 2011, 00:57
I know lowering the nose that one time regenerated the stall warning but these guys were not pilots they were computer operators. We need our pilots back flying our airplanes, not computer operators.

bubbers44
3rd Sep 2011, 01:03
Can you imagine one of these computer operators trying to fly a B17 back to England with their talent?

grizzled
3rd Sep 2011, 03:49
bubbers44


Does anybody here believe the PF was not at fault by pulling the SS full up for 3 minutes until impact with the ocean?


Well... That depends on what you really mean by your question. If you mean "were the PF's actions the primary cause (or one of the primary causes) of this crash?", then, from what we know at this point, the answer is "yes."

If you mean "were the PF's actions the sole cause or contributing factor to this crash?", then the answer is clearly "no". In other words, it took a lot more than his actions alone to bring this aircraft down. (I.E, that night, during the event, one would include: Actions of PNF, inaction(s) of PNF, actions/decisions of Captain, and, as a contributing factor of course: pitots. Other contributing factors: AF training, AF SOP's, airline hiring and training in general, intrumentation perhaps, etc etc.)

Your use of the word "fault" muddies the waters in terms of accident analysis. But if you insist, and really do mean to ask, "Was it the PF's fault the a/c crashed?", the answer can only be, "partly."

daelight
3rd Sep 2011, 03:54
Blubbers & Co. of the Sensationalist Anti-future Brigade ... Your soundbites make me sick!

You and others have the audacity to flippantly remark that pilots are not able to fly their aircraft? Shame on you.

Safety Concerns
3rd Sep 2011, 05:39
You and others have the audacity to flippantly remark that pilots are not able to fly their aircraft?

with respect daelight that is exactly what the FAA, manufacturers and some pilots are now beginning to accept. Not the fault of the pilots but industry has been allowed to dumb down a little too much.

xcitation
3rd Sep 2011, 06:22
Does anybody here believe the PF was not at fault by pulling the SS full up for 3 minutes until impact with the ocean?
Obviously his actions were wrong, the question is why?
Also he was not alone. PNF and CAPT failed to identify the situation. PNF appeared early on to nag him to "go back down" which was ignored. To me the collective delusion, bar room level communications makes the incident even more puzzling. I have struggled to explain nose up by them applying wrong procedures, or bad instruments, side stick input failures. But nothing fits. Near the end the PF confides he has been nose up max all the way! Like it is the normal thing to do and he tried his best to pull out of a dive or something.
Why is it that when we look at the recorded data do their actions make no sense. Far too simple to say that all 3 failed. Only a video would answer the question - which is what BEA are recommending going forward. To me there is a piece missing. Is it possible that the recorded data differ from the actual displayed data on the PFD etc?

jcjeant
3rd Sep 2011, 08:11
Hi,

Only a video would answer the question - which is what BEA are recommending going forward. To me there is a piece missing. Is it possible that the recorded data differ from the actual displayed data on the PFD etc?

Not sure
This can be also a false interpretation of what they seen
People often see things differently from what is reality
After a car accident .. when eyewitnesses are asked .. they will often tell a different story from that of other

kwateow
3rd Sep 2011, 08:30
"Only a video would answer the question - which is what BEA are recommending going forward"

xcitation, what does "going forward" mean?

chrisN
3rd Sep 2011, 10:53
Xcitation, you ask “Near the end the PF confides he has been nose up max all the way! Like it is the normal thing to do and he tried his best to pull out of a dive or something. Why is it that . . . ?”

PF’s references to “crazy speed” and his persistent holding nose up suggested to some that he confused mach buffet with pre- stall buffet, and high noise with high speed rather than high AoA, which kept him thinking all the way down that he had an overspeed problem. What do you think?

Chu Chu
3rd Sep 2011, 11:42
kwateow,

Here's BEA's summary of their recommendations on flight recorders:

"One recommends that the regulatory authorities require that aircraft undertaking public transport flights with passengers be equipped with an image recorder that makes it possible to observe the whole of the instrument panel. Another recommends defining strict rules relating to the use of such recordings."

jcjeant
3rd Sep 2011, 12:46
Hi,

kwateow,

Here's BEA's summary of their recommendations on flight recorders:

"One recommends that the regulatory authorities require that aircraft undertaking public transport flights with passengers be equipped with an image recorder that makes it possible to observe the whole of the instrument panel. Another recommends defining strict rules relating to the use of such recordings." Another more "black box" to retrieve .......
Why not electrodes placed on the heads of the pilots to record the activities of their neurons ? :ooh:
Another more "black box" to retrieve ......
More "black boxes" = more safe flight ?

Safety Concerns
3rd Sep 2011, 13:00
More "black boxes" = more safe flight ?

well actually it does. We would be better able to work out why something happened. I remind you that in stall situations on other less modern aircraft the crew did exactly the same and pulled back on the stick.

We will never know why but images may well help to explain why. Once we know why we can develop a safer system.

jcjeant
3rd Sep 2011, 13:47
Hi,

Funny you should say that...Not so funny ..
well actually it does. We would be better able to work out why something happened. I remind you that in stall situations on other less modern aircraft the crew did exactly the same and pulled back on the stick.
as the pilots unions (their primary concern is of course the safety of the flights for their members and the passengers as all we know ... ) will refuse it .. as they already in the past refused video recording in cockpit...
Or maybe a extra increase of wages as incentive will make change their view on those safety problems ? :8

lomapaseo
3rd Sep 2011, 17:09
Safety Concerns

More "black boxes" = more safe flight ?

We will never know why but images may well help to explain why. Once we know why we can develop a safer system.

I doubt that .... in the end we only think we know why and still will address the same contributors.

We know the leading contributors now ... let's get on with putting the resources there rather than waiting to satisfying our last subjective doubts with video recordings.

Just look at the CVR, do they prove anything? or do they just focus us to consider possibilities?

Safety Concerns
3rd Sep 2011, 17:42
well it is a dilemma I accept. However every little bit helps I would say. Video would require strict controls and a short recording period. Most accidents happen pretty quickly.

But I believe they would bring something positive to accident investigation.

Lyman
3rd Sep 2011, 17:43
Simultaneous reject of ADs. All three. This suggests Ice was not at work, but something else. Entry into upwelling airmass, which decreases the speed readings. What else is affected by a large shift in wind direction? AoA vanes, which would read (again, simultaneously) falsely high, perhaps quite high. What would the AutoFlight do? Decrease thrust, and PITCH DOWN, Another result? WIND SHEAR, and TCAS action.

As the a/c responds, the computers have by now rejected the airspeeds as too quickly divergent from cruise speed, and the a/p drops out.

The a/c has 1000fpm UP/VS, the Nose is DOWN 4 degrees from cruise, and due a tangential entry into the upwelling vertical, a ROLL (Left wing rise, to be more precise).

This is all on the traces, (save for the tangential entry) for the last four seconds of autoflight. I repeat, it is on the traces supplied by BEA.

The false high AA's and low "speed" have caused a spurious STALLWARN in the cockpit, as PF takes over. All but this have been done to death. Anyone? TurbineD?

So would a "resident" LKas (Last Known airspeed), have helped? Subject to inertial updating? A reserve Probe, to enter an abruptly presenting "new" airmass, and sample the "new" attitude dependent a/s? Because if this is what happened, then the Probes are fine, and the Autoflight needs some serious work.

hetfield
3rd Sep 2011, 18:46
@safety

Obviously you don't like these questions.

So what the hell with a (still) living PPRuNer ?

Get along with the facts!

Safety Concerns
3rd Sep 2011, 19:33
there is nothing mysterious about pilots not being in tune with their aircraft. Scary yes, mysterious no.

mm43
3rd Sep 2011, 21:18
Originally posted by Lyman ...
Simultaneous reject of ADs. All three. This suggests Ice was not at work, but something else. Entry into upwelling airmass, which decreases the speed readings. What else is affected by a large shift in wind direction? AoA vanes, which would read (again, simultaneously) falsely high, perhaps quite high. What would the AutoFlight do? Decrease thrust, and PITCH DOWN, Another result? WIND SHEAR, and TCAS action.Now that 'take' on what may have happened is not unreasonable.

Away back in the 'AF447' thread I posited that mesoscale system to the east of 447 had a high level clockwise circulation. So it could well be that the pocket of upwelling air that confronted the a/c could have also been a southerly of + 60 KTS. If it had impacted the right wing first, the wing would have lost lift and hence the right roll and nose down.

Perhaps a closer look is needed, though super cooled icing could also have played its instantaneous card - as the conditions seemed to have been ideal for that phenomenon.

Turbine D
3rd Sep 2011, 22:16
Lyman

Re: Thales Cleared

I don't think so.

What would the AutoFlight do? Decrease thrust, and PITCH DOWN, Another result? WIND SHEAR, and TCAS action.

@ Just prior to 2h 10min 0sec, they are cruising in A/P A/T @ 282 CAS and a Mach of 0.82

@ 2h 9min 58sec, the speed handling is change (probably by the PNF, my words) from managed to selected. The selected Mach is 0.80, the turbulence penetration speed.

@ 2h 10min 0sec, the pitch attitude decreases from 1.8° NU to 0° in 3 seconds and the engine N1 begins to decrease from 100% to 84%, reaching 84% in 8 seconds. This was accomplished by moving the thrust levers while remaining in A/T, my words

@ 2h 10min 03sec, the nacelle anti-ice switches for the engines are changed to ON.

@ 2h 10min 05sec, the A/P2 disconnects. The roll angle changes from 0 to 8.4° in 2 seconds but the sidestick is a neutral. The pitch atitude is 0°.

@ 2h 10min 06sec, the flight control law changes from normal to alternate.

@ 2h 10min 07sec through 2h 10min 18sec, the copilot sidestick is positioned:
- nose up between neutral and 3/4 of the stop position
- to the left in half-travel position then to the right in half-travel position and twice, alternatively left to the stop position then right to the half-travel position.
- The pitch attitude increases to 11°
- The vertical acceleration varies between 0.9 g and 1.6 g.
-The roll angle fluctuates between 11° right and 6° left.
- The vertical speed increases to 5200 ft/min.

@ 2h 10min 08sec, the FD1 and 2 become unavailable. The A/THR disengages and the THR/LK mode is activated. The N1's are 83%. The CAS changes from 274 kt to 156 kt. The CAS ISIS changes from 275kt to 139 kt then goes back up to 223kt. The Mach changes from 0.80 to 0.26.

Now I am going to skip a little bit to around 2h 10min 17sec. It is here they recognize the THR/LK is active. I think shortly thereafter then they reset the thrust levers back to 100% N1 as depicted on the chart, my words.

So you see, the speed changes were made by the pilots not the A/THR. They also recognized there was the likely presence of ice or they would not of turn on the nacelle anti-ice. This recognition came a little late and was probably due to the use of the weather radar. They had it set on a long range ND and reduced it several times which lead to the request by the PNF, "You can maybe go a little to the left I agree that we're in manual, eh?" The magnetic heading selected decreases to 34° from 35.5°. The pitch down may have resulted from the decrease in Mach and the roll back of the N1 from 100% to 84% and was only from 1.8° to neutral.

The roll tendency is interesting, something that I can't explain other than the weather situation at the time.

These are my thought, I think the pitot tubes icing started the event as they entered a weather system perhaps they should have avoided.

Lyman
3rd Sep 2011, 23:39
TD

At ~2:10:02, the a/c is VS 1000fpm UP. The PITCH is ND 4 degrees from cruise.

This is exquisitely consistent with entry into a robust Updraft. If this upwelling has a velocity of 60 knots, we take 6000 fpm as the new airmass vector to add to the horizontal of cruise. This produces a distinct reduction in air speeds. All that is required is a reduction of 30 knots in the sensed a/s in less than one second, and the ADs get tossed.

To cause a 200 tonne a/c to climb @ 1000fpm might require an updraft of such a value, quite high. Then we can add to the a/c Attitude the free moment arm of the Horizontal Stabilizer, elevators. The mass will not lift immediately, but it will articulate longitudinally, ie: tail UP, Nose DOWN.

Those two bumps at the tail end of a/p duty are interesting.

Thanks for your reply :ok:

mm43... I continue to try to put together the airframe responses prior to and during the PF's capture of the controls. Obviously, it is here that I will look with great care, firstly because BEA have left it unaddressed, and the data is sparse; Secondly, the rest of the released data and all the one sided rhetoric shouts: SORTED! I don't think so, but it is largely irrelevant to me, the fascinating discussions are a follow on to an almost immediate LOSS of control, so this is where the Grail must be......

cheers :ok:

bubbers44
3rd Sep 2011, 23:57
The next time you are at FL350 at M .82 in your airliner try pulling the controls into a full nose up position. Guess what, you end up 3,000 ft higher in a full stall. It will happen every time. No updraft in my opinion. Just bad aviating. I think the FDR supports this.

Turbine D
4th Sep 2011, 01:03
Lyman

Re: Vertical Speed

A 1000 fpm vertical speed up sounds like a lot, that is, if it lasts a minute or more. It didn't. The A/P handled it very well and within seconds it was back to neutral. It was like a bump experienced in moderate turbulence. However, approximately 12 seconds later, it increased dramatically, about the time the sidestick was in use by the PF, that's when it increased to 5200 fpm.

CONF iture
4th Sep 2011, 01:31
@ 2h 10min 0sec, ... and the engine N1 begins to decrease from 100% to 84%, reaching 84% in 8 seconds. This was accomplished by moving the thrust levers while remaining in A/T, my words
No - The thrust levers were not moved according to the TRA traces P113 EN.

... around 2h 10min 17sec. It is here they recognize the THR/LK is active. I think shortly thereafter then they reset the thrust levers back to 100% N1 as depicted on the chart, my words.
Again, TRA traces don't show that. First time a thrust lever movement is recorded is just after 2h 10min 45sec
But, the thrust levers must have been quickly recycled out of and back into the CLB detent around 2h 10min 22sec in order to leave the THR LK situation (P108 EN), quickly enough that nothing has been recorded on the TRA traces. IMO.

Lyman
4th Sep 2011, 01:56
TD Yes, 1000 fpm is perhaps 13 knots. The importance of this value is not the velocity, but the energy involved in moving the airframe. For this, any UPDRAFT acting in a three second frame to move 200 tonnes has large energy values, as above, let's put it at 6000 fpm.

More important is the Moment arm of the Tail, it lifted the aft airframe up until the body caught up, at this point the evidence is that the NOSE was PITCHED DOWN. So the a/c is PITCHED ND, and moving UP at 1000 fpm.

Again, it is the energy, not the velocity. This preceded the Pilot's back stick, and again, he was not patient, the a/c was starting to move, and he was inputting the ss max. The FCS loaded the airframe, which was already moving, and this caused the rapid climb. We know that the NOSE was rising at a/p drop.

Keep in mind that with Tail high, a "rotation" will drop the tail very quickly, to accomodate the desired PITCH UP. This is a very emphatic rotation, similar to TAKE OFF, and at T/O Pitch can easily be 15 degrees UP. This explains the radical PU, for me. Once at this PITCH, and w/o cues, the PF hasn't the clues he needs to pin the PITCH. If the energy latent in the column was still in play, the climb becomes a very problematic maneuver.

Now I cannot divine the cues and clues, and his maneuvering has me at a loss, but if I entertain the preceding holes, I gain some perspective, relative to the initiation and maintenance of the climb, which led to the STALL.

Which is the place I have been since day one, why the UPSET?

regards, Sir

Danny2
4th Sep 2011, 14:09
Due to the incessant, speculative, hamster wheel evolution of this thread, it has been decided to move it to the Tech Log forum for posterity and close it. There is already a thread in the Tech Log forum on this accident and any further debate can carry on there.