I agree.
But I was trying to follow the Sim Stall and thinking " What if, at apogee PF HAD suddenly realised ( At Last ! ) we are stalling...Merde.... And PJ2's experience on the Sim might be..."
I should have been clearer.


OK465
The oil pressure instrument on my car is backed up by an oil pressure warning light which comes on if the usual pressure is missing.
Similarly the THS could have a warning when it exceeded certain a figure. This might have made it easier for any of the three pilots to notice and wonder why.

LT.

Salute!

No problem, Doze. I need to express myself more clearly and referring to a post you made a year and a half ago.

- By "feel" and "touch" I am talking about vibrations, noises, thumps and bumps, and even the airframe shaking so badly that it's hard to read the instruments. Ask Retired about flying the F-4 at high AoA.

I am not talking about "artificial" feel in the controls. You know, springs, dampers, bobweights, etc.

Really good pilots will KNOW when something is not right. They might detect a different noise from the motors. They might feel a vibration that wasn't there a second ago. In other words, they are tuned to the aircraft, regardless of the flight control implementation. (On private, ask me about one day I "felt" something and saved the jet)

- The disregard of AoA by the 'bus system in some modes bugs me. I fully appreciate that at very low dynamic pressures, the AoA sensors are close to useless. But seems to me that the 'bus ignores the AoA when the "system" determines that airspeed is invalid, or speed too low. Sad, because the wings certainly know if they are stalled, so the sensors should still be valuable if the crew is in doubt.

So I was not clear about "override". You are correct. The system allowed the pilot to exceed the stall AoA and the pilot may have still thought that he couldn't stall the jet.

Interestingly, our first operational FBW jet ( over 4,000 built) even "protected" the pilot from overriding the system limits until AoA was over 30 degrees. Then we could manually control the horizontal tail and "rock" outta the deep stall by holding a switch with one hand and rocking with the other hand on the side stick.

++++++++++++

I fully agree with Doze and others ( last paragraph of his last post). Why the pilot pulled back and then held the stick back for so long is a mystery. My opinion is he was more concerned about overspeed initially, but after that......

Gums

HazelNuts39

Howdy. Is there any possibility at all that RHS was following in his scan the V/S (SELECT) at 5000fpm descent at a/p loss, confused it with the Nose Down he saw at takeover, and imprinted it in his initial S/A? Therefore the NU?

Perhaps Farley can explain how difficult it is to hover the Harrier. A friend tells me its like doing jumping jacks on a bowling ball. I tend to use that thought when I envision a/p loss on 447. It was difficult.

Flight is a continuum, one takes a break from the flow at great risk. I try not to be too dismissive of how difficult it turned out to be.

As to the DFDR/CVR contents? To consider any part of it to be "off limits" to anyone with appropriate expertise is to deny the concept of a Democracy.

Especially at Court. The Plaintiff is denied access, whilst the defendant has a copy on the coffee table? Please, some perspective.

Hi Dozy.

Yeah, but you can't design airliner safety concepts around the assumption that the pilots will be "really good". Average ability must be assumed, alongside failsafes to catch pilots having a "below average" moment.

It doesn't "ignore" AoA during UAS, otherwise Stall Warning wouldn't work. It can't use AoA data for protections during UAS because the redundancy calculations are defeated. Low airspeed is a tough one. As was the case a while back, I'm prepared to bet that similar cut-off points are used on most modern airliners, not just Airbii.

mm43;
The "high frequency component of an amplitude increasing to until about 0.1 g peak-to-peak,"(...) "vibrations that might correspond to buffeting" that BEA speaks about on pages 43-44 have a period of about 0.5 seconds.

Doze.

@DozyWannabe
Yeah, but you can't design airliner safety concepts around the assumption that the pilots will be "really good". Average ability must be assumed, alongside failsafes to catch pilots having a "below average" moment.

That is precisely the beginning of the Hamster Wheel that will perpetuate these wrecks. The Spiral of "Better Automation", "Diminished Ability".

Do you see the connection?

Not really, because you just cross-check with the altimeter, and as long as it's not unwinding drastically, you rationalise the V/S display as a turbulence-related blip.

Difficult, yes - but as difficult as hovering the Harrier? I don't think so. The Harrier is notoriously tricky to control in hover as it's not very stable and you're only about 50ft or so off the ground, whereas the A330 is *extremely* stable, and in this case was handed over at cruise altitude, with a reasonable speed setting. The AF447 PF could in all likelihood have kept his hands off the stick and nothing untoward would have happened.

This isn't about denying content to those with appropriate expertise, it's about air accident investigation *needing* to be a special case to prevent possible further accidents between the time of the accident and the court case. I was accused of naivete on the other thread for saying that Airbus had to be given the FDR data for technical reasons and not for the benefit of their legal team. I'm sure their legal team have seen some of it, but until the final report is released and the trial begins, I don't think they'll have looked into anything the BEA consider non-relevant (and remember, the distinction of relevance is made by the BEA, *not* Airbus).

It's also interesting that you use "Plaintiff" and "Defendant" in that manner - strictly speaking, the crews' families, Airbus and AF are what Anglo law would consider co-defendants. With the evidence as it's laid out in the 3rd Interim Report, it seems that all three are likely to come in for a degree of censure - mishandling and poor CRM for the flight crew, failure to expedite replacement of the Thales pitot tubes for AF and Airbus, and poor management and training practices on the part of AF.

I've said my piece on automation elsewhere. Automation is a tool, nothing more - if that tool is being used to skimp on training and development of handflying, then it is the fault of those using automation for that end, bot automation itself.

Hi,

Gums
Indeed ... A good example is the pilot Hans-Joachim Marseille "The Star Of Africa"
He flew with gym shoes instead regulatory boots
He has said to Willy Messerschmitt:
I made ​​one with my plane .. I must do no more to focus on instruments .. all my concentration may well be on my target

The court of justice in charge of the case is located in Françe and apply french laws .. not Anglo laws

Re, "How do you train aoa instrumentation if it is never to be used unless in upset!"

The natural place to be using AOA is on approach. That is where to begin training to use it. Once the indication is worked into your scan, you can begin to use it elsewhere in the flight envelope.

I'm well aware of that, I was just making the point that Lyman's insinuation that the non-release of raw FDR data to the public and/or the crew/family lawyers was equivalent to the prosecution withholding evidence from the defence in a criminal trial was false.

Learning curve
 

Hi,

PJ2:


Due it's importance (to the wing "function") i think it "self teaches". And (perhaps) should be used in training.

I admit, it collides with Airbus SAS philosophy of "stall prevention" through "protections".

But (may play an important role) can be vital in (rare) extreme cases.

Mac

(Controversial, :confused: )

Trend?
 

Hi,

Bear:

Important point!

Mac

PS

Is training capable to "prepare" when applying this approach (to the limits)?

@DW

QUOTE
I'm well aware of that, I was just making the point that Lyman's insinuation that the non-release of raw FDR data to the public and/or the crew/family lawyers was equivalent to the prosecution withholding evidence from the defence in a criminal trial was false.UNQUOTE

[B]NO[B] In juris civile, Plaintiff and Defendant are no less adversarial. Perhaps more so. "NON RELEASE". That means what, like "Withheld?"

Witholding evidence can be charged in itself as a felony. Even a jurist can be recalled for indiscriminate actions.

Let me ask a non threatening question, Doze. Say you are in Upset, and you see your Pitch as 7 degrees. You have no idea your AoA, it is at 40 degrees. You ok with that? Any problem? You cannot suss anything of help, and your g is around "1". Still ok? Right, AoA is ok in the computer quiver, but not in the Pilots'?

You seem to have forgotten that at the time of this UAS, Pilots were told to Disregard the STALL WARN. Also, the a/p was not yet accused of "Uncommanded climb".


Also @DOZEWANNABE:
(FBW) "It doesn't "ignore" AoA during UAS, otherwise Stall Warning wouldn't work."

Can you say that the SW did work? Evidently not, and for the same reason the pilots could not Suss the STALL. The AoA was not available. Could one explanation be that the pilots did not even acknowledge the WARNING because they all tacitly took it to be bogus? You have a better question than "How could they ignore the STALL WARN?"

Lyman,

Read my post in the other AF447 thread regarding release of information...

TD

Maybe you should ask a pilot which I'm not. The trace of V/S Selected on page 111 prior to A/P disconnect shows 0 fpm with regular 'spikes' to -5000 fpm (the much debated 'zipper'). After A/P disconnect the spikes disappear and the trace shows 0 fpm for about 15 seconds and then starts jumping up and down to +5000, -5000, +5000, 0, +11000 where it remains for about 20 seconds.

The FD was not available immediately after AP disconnect, but briefly reappeared about 10 seconds later.

I'm afraid I don't understand your question.

Thanks TD I have. Both you and Dozy are absolutely correct. Save one: At its completion, the Final Report is not given to the Judge, it is provided EASA, isn't it? Thence to parties deemed important by the authority. BEA has no power, they are "Party to" ?

HazelNuts39. Sorry, I just wanted to know your opinion re: its availibility to PF, not his reaction to it. Your response is perfect. From it, I conclude the zipper may have held his attention as to V/S and influenced his inputs, perhaps well into the "climb". My opinion only.

Further, the display of V/S select, appearing (post a/p loss) "erratic", may actually have been accurate, but further confused the pilot as to his "climb".

I only suggest that the "zipper" can't just be discarded as irrelevant.....
Had he not judged his V/S accurately, how was he to suss his actual ROA?

Key points
 

Hi,

PJ2:

Therefore, a "practically impossible" stall recovery, given the "environment" they were in and their "possibilities" to tackle the task.

You are assuming this will be only "understood / explained" by HF study results?

Mac

Back to AoA one mo' time
 

Salute!

@ Doze:

Redundancy is required, no problem with that. OTOH, graceful degradation is also required. So why throw out the one sensor that actually indicates the ability of the wing to provide lift or lack thereof? By the time the AoA sensors are invalid I can guarantee that the plane's wings aren't providing useable lift doofers.

'bird has it right. Start off using the AoA for approaches, as it inherently compensates for weight and such to provide the best aid in the cockpit.

Being a USAF jock, we used a baseline speed and added knots for fuel weight and such. The U.S. Nasal Radiators used the AoA indexer lights and such. So I was impressed once flying the A-7D, which was a Navy design which the USAF adopted and improved. Gotta tellya that an approach was much safer and easier than what I had been used to.

Sure, a good crew will compare the speed based upon weight with the AoA, but once close, AoA was the primary aid for an approach.

Once gear up, our Viper AoA "bracket" went away. Due to our operational requirements and design of the FBW system, pulling full back gave you the best AoA for the gee you were commanding. By the time you reached the max AoA you were in one Gee flight ( we hit 9 gees at 15 degrees).

For the 'bus, I can see an AoA indication in cruise configuration that is small and basically unimportant. But when the system starts to revert to backup modes, then the thing might be the best friend you have, especially for a pitot-static problem. And then there's the flight path marker (FPM) produced by the inertial system, which show exactly where the jet is going without regard for any aerodynamic sensors.

I can not imagine seeing the FPM at the bottom of the indicator or HUD and not thinking about being fully stalled while holding back stick, can you?

Gums

Having now spent time in an A320 simulator, I can tell you that in MANAGED mode, the corrections applied by the autopilot are displayed in that window. "-5000" appears, but only for a fraction of a second as the slight corrections are applied. I'd be very surprised if that interrupted his instrument scan (of which the FCU display should only be an occasional part) and led him to conclude they were descending for two main reasons.

1. They are a regular occurrence in MANAGED mode, and lots of corrections are expected in this scenario. He may have been relatively low-hours for an airline pilot, but this is one scenario where spending a lot of time with the automatics in would have led him to discount that as anything to worry about.

2. He did not start climbing until the automatics disengaged, at which point (as you'd expect), the "zipper" stops.

Why the initial pitch-up?
 

Hi,

Considering we fly near the "corner" i ask:

Why not to implement (ASAP) a "resource" to indicate Stall type.

The system (IMHO) is able to process and inform reliably on low speed or overmach stalls.

Thiells 727 man machine interface mislead 3 crew. (Redundant misleading of Climb and Alt)

Current Systems, it seems can indicate precisely Stall type:


Why the pilots (sometimes near the corner) should only guess?

Mac

This "guessing" (wrong) probably was the most important factor in AF447 loss.

From PJ2 Describing SIM, 447 profile, STALL

"The overriding impression of these sessions was how quickly things occurred and how fast was the altitude loss."

If RHS could have been debriefed, would he have stated something similar?

Substituting "GAIN" (altitude) for "Loss?"

DOZY, I refer to SELECT, not MANAGED. I have a further question, but probably for an engineer. What is the damping for a 5k fpm ascent/descent? Is the bellcrank, A/Rod protected from sequential deflections, followed by a withdrawal of input? Are the inputs density compensated? I am sure they are. Having seen the deflections of a preflight Stabilator check on F-16, they are emphatic, to say the least.

Another thought. Could the .5 second cycle .1g amplitude "vibration" have been a stammering elevator select? OR THS stutter? Just a mechanical question, nothing more.

Lyman - read what I'm saying. In MANAGED mode, the corrections applied by the autoflight system are displayed in the SELECT window of the FCU panel. I want to make clear at this point that we're not talking about control inputs of a magnitude to effect 5000fpm descent rate immediately, simply that this is the value the software uses in certain configurations. Lower to the ground, you'll see -1500 appear in the window for a split second as corrections are applied, but you don't start descending at 1500fpm.

Not surprised we are not communicating well. You haven't touched on my question. Perhaps let's just give this dialogue a rest. I'll just read. You're the Pilot rep.

The buffet onset envelope is determined in flight test before the type is released into service. It is scheduled in the AFM, the FCOM, the QRH and in the FMEGC. Stall warning is set to occur at an AoA 1 degree less than buffet onset. The recorded 'signature' matches that previously obtained in flight tests. Why would the elevator begin to stammer and/or the THS stutter at the precise moment that the airplane enters a regime where buffet is known to occur?

Fault Tolerance, Graceful Degradation, Redundance and SURVIVABILITY
 

Hi,

Before the day the Systems becomes PERFECT and EVERY possible situation is simulated and TESTED, as a designer i would prefer to deliver planes with "small resources" (like AoA) capable to save POB.

gums:

Quote:

---

But when the system starts to revert to backup modes, then the thing might be the best friend you have, especially for a pitot-static problem.

---

:ok:




Mac

PS

Is seems something like the AoA indicator (proven in EXTREME conditions) lies in the "Tectonic Fault" dividing who:

1) Think a System (and the crew) is capable to work always as expected.

2) Known (battle hardened) that sometimes you must be able to do the "necessary" to survive.

Airbus SAS or Air France or authorities (or AF447 crew) made what was possible:

1) Maintained hundreds of A/C relying on OBSOLETE AS sensors

2) Didn't replace the WORSE obsolete sensors in time

3) Didn't anticipate possible PROBABLE ("recurrent") scenarios.

4) Didn't act with it's authority capabilities

5) Didn't even understand what "was happening" yet before entering WX :{

Perception "means" survivability:

Thousands of professionals IMO didn't act proactively.

And Murphy Law again put the toll for that collective failure (merely a probability result).

PS

Well, if AoA gauge has no place in the cockpit at least his data could be used to "inform" the stall type. :}

@HazelNuts39
I agree with that, and I should have written before the wine glass was empty! Possibly the point I was trying to make, was that the onset of the 5Hz 0.6g (p/p) at cockpit vibrations occurred as the 0.2Hz oscillation of the pitch attitude and AoA commenced. The amplitude of this "buffeting" has risen in tandem with the increasing amplitude of the 0.2Hz longitudinal pitch/AoA oscillation.

I wonder if PJ2 noted anything similar in the SIM? Possibly not, as that aspect of the airframe dynamics was then outside the known flight envelope.

@PJ2

Quote:

---

Originally Posted by PJ2

I'm not sure what you mean by "effective aircraft

---

This excellent 1997 book that Machinbird advised me, shows 51 references of "Effective aircraft" to explicite the definition: Aviation safety and pilot control: understanding and preventing unfavorable Pilot-Vehicle Interactions isbn=0309056888...National Research Council (U.S.). Committee on the Effects of Aircraft-Pilot Coupling on Flight Safety - 1997 - Transportation - 208 pages
Implications for Design of the Effective Aircraft Dynamics Reduce time lags in the high-frequency effective aircraft dynamics. To reduce tendencies for ...

Quote:

---

Originally Posted by PJ2

](no) unusual difficulties which require [...] (particular) skill or knowledge

---

These characteristics are required for certification, but have nothing to do with system "controllability"

Quote:

---

Originally Posted by PJ2

eminently, (éminemment), "observable and controllable"

---

Observability and controllability don't have to be eminent, they just are mathematic.

Quote:

---

Originally Posted by PJ2

Nor do the accident rates indicate a large difference between aircraft types

---

I assume you refer to A/B ? I have no royalties in any, nor in other manufacturer, nor in any insurance/aircraft financer. I am only involved in flying pleasure, pilot safety, and mathematic accuracy.

Quote:

---

Originally Posted by PJ2

However, no aircraft, no design I know of is controllable or observable when it is taken into a full stall.

---

False :
1. In any pilot school over the world, stall is teached to get private pilot. Would this manoeuver be uncontrollable and the international civil aviation allow that ?
2. AF447's A330 finally seems to stall like many others aircrafts stalled : you just have to push to stop the stall .Gums quoted F-102, Concorde, Viper having analog stalls.Yourself said it is the case also with B777 and A330 D-sim. Is that uncontrollable if the pilot learned that ?
3.The french pilot school where Air France teached his young pilots (perhaps Bonin), IAAG/EPAG uses for VFR and IR learning the Socata TB20 Trinidad. This aircraft stalls in just descending, unstalls just with pushing... Would this manoeuver be uncontrollable and the french civil aviation allow that if it was ?
4. All the aerobatic pilots, including fight pilots regularly stall and spin, controlling perfectly their flights.. We like to look them and we could not imagine one second their flight is not controllable. Are they ?　

Quote:

---

Originally Posted by PJ2

AF447 was recoverable even after entry into the stall but it required that the stick be pushed fully forward and held there until the wing began flying again. That would take between 15,000 and 22,000ft (I've flown this in the sim many times). This is Machinbird's "unloading of the wing" to which he referred some pages back.

---

Quote:

---

Originally Posted by Machinbird

And Presto! we have some numbers and they show that

---

Quote:

---

Originally Posted by Machinbird

If you do not mess it up you would do surprisingly well

---

Quote:

---

Originally Posted by HN39

The "on the threshold of stall warning" trajectory with specific excess thrust (T-D)/W = 0.15 results in level off after 15 s (was 18s) at FL76, Mach 0.51, 295 kCAS, az=2,24 g.

---

The final loss of height is not your 22000 FT, nor FL200, nor 15000 FT,
but 5000 (max) +(FL100-FL76)=7400 FT

Quote:

---

Originally Posted by PJ2

Said another way, a B777 pulled up in the same manner and handled the same way as this aircraft was would also crash

---

Are the B, C, D, etc pilots hammered with "B, C, D, etc. can't stall" ?

Quote:

---

Originally Posted by PJ2

sidestick vs control column

---

Both may be tried, used. if correct. The problem of observability, governabillity, man-machine interface is not which actuator, but how it is connected to the effective system. I have no royalties in any manufacturer, and I choose to put philosophy in library not in aircraft.

Quote:

---

Originally Posted by PJ2

This is the part that is very definitely not complicated

---

Quote:

---

Originally Posted by TurbineD

However, it is more complicated when you can't interview a key person in the problem loop. When this happen, you have to make a list and go through the process

---

Quote:

---

Originally Posted by PJ2

In the present system, 99.9% of flights work well with SOPs, CRM, appropriate use of automation (according to enlightened airline policies which permit hand-flying), but the loss of such skills is nevertheless no longer a blip but a trend

---

.

That is very dangerous ! Every sixty seven hours you have a four minutes crash ! I choose to fly with "these guys [...] (who) knew how to stay alive, (many of them are here, thank you !) and not in your "managed airlines" and their effective aircraft.

roulishollandais

So what I'm looking to eliminate is the zipper as Alpha Prot, considering there was turbulence, UAS, and an actual SW for the Pilot flying. His input did not have time to actually change the AoA, so I'd be looking for some combination of local W/S to duff the AoA vanes. Since STALLWARN is available in ALTLAW2, it wouldn't make any difference whether in autoflight or manual.

just askin'

Whether the Law degrade was due imminent STALL (actual or AoA A/S sensed) or UAS, or computer malfunction, would it be important to know what ND value would obtain given autoflight's need to correct, WARN? Would it be 5000fpm/ND?

Because that would be almost like foul play, eh? "We're about to STALL, Your Aircraft"........."Oh, and LAW CHANGE"........"SeeYa".........

A-330 Instructor Manual
 

MM43, thank you for providing this valuable link to the manual. Very interesting. I used to have the 320 version but no longer do.

Hello Lyman;

In re the autopilot disconnect and, "It was difficult. " (post #1124)

No, it was not. And a disconnect is most certainly not like "hovering a Harrier".

An autopilot disconnect is a non-event.

If the airplane is descending/ascending slightly when the disconnect occurs, a gentle nudge on the stick (millimeters in terms of movement of the top of the stick) brings the airplane back within the expected requirement, which here is maintaining a cruise altitude.

A disconnect simply is unimportant to a pilot - and absolutely should be a non-event. One takes over, commands the airplane and makes it do what you want, returns it to what you were doing before the disconnect, and when available, re-engages the autoflight system. It's what we do.

The terms "Select" and "Managed" have specific meaning for Airbus pilots. They refer to an autoflight mode where control of the aircraft is either through the MCP (Mode Control Panel - autopilot panel) or the FMGC.

When the AP disconnects and there is a rate of climb or descent occuring, (including a small deviation such as occurred here), the vertical speed window will display VS (as opposed to other modes such as FPA or just dashes in "managed" mode). In other words, the display defaults to VS and will show what the rate was at disconnection but isn't a "command"...it's just information at that stage.

In terms of response, no pilot is going to slavishly follow an FD command to "descend at 5000fpm" because a flight director says so. He is instead going to "look through" the temporary FD "command" and get his airplane gently back to cruise or whatever it was doing prior to the disconnect and get on with the drills/checklists. No big thing. Really.

Hello, Machinbird;

I do appreciate your comments and the fact that you present such a different view of 'the wing' than I have as a transport pilot - it is very engaging and well worth the discussion, thank you.

Re, "The natural place to be using AOA is on approach."

I like knowing and using AoA. I used to interrogate the ACMS Alpha Parameter functions on the ACARS units all the time and keep the AoA displayed down on the pedestal especially during heavy turbulence. So it can be done (though it isn't taught!), and likely easily with software and pixels (rather, raster scan!).

So I do not argue against an AoA presentation to the pilots...I like it and agree that training on it would be straightforward in terms of the mechanics of learning and applying the information. I am not personally arguing against it but I'm recognizing some of the impediments to making the change and the likelihood of such change in the face of certification regs, training/standards/checking and the like. Airline budgets are thinner than they ever were and "safety as a business case" is not an atypical approach, it is THE way it is done. Agree or not, cost and cost control are enormous factors in daily operations.

The one argument which I think may be convincing is in knowing that one was stalled but the counter-argument is, the blaring "Stall, Stall" and loud warning chirp didn't get their attention...would AoA have? What else does a pilot need to tell them their aircraft is stalled?

The industry has been largely successful without AoA so the argument that AoA would have "saved" AF447 vice other standard handling procedures (not stalling, pushing the nose down once stalled), is not convincing. It wouldn't have saved Colgan, it may have saved the Airborne Express DC8, it may have saved the FedEx ATR72 at Lubbock and (IIRC) a B727 where the pitot heat was turned off, but in the millions and millions of hours flown in all types, lack of AoA has not been an issue until AF447.

So the argument must demonstrate that an AoA indication would have made a difference to the outcome, for this crew and while it may have, we just don't know. The captain may have noticed from his vantage point and called out "push down!"...we don't know. I agree that one accident prevented makes such change highly desirable but again, what shall we argue next? I absolutely know through data that there are some things that can be done right now that would prevent CFIT and overrun accidents in the approach and landing phase but short of exorting the stabilized approach, very little is left up to technology and presented information.

But we could have an electronic "energy-status bar"...showing the potential landing distance, even on contaminated runways as a digital presentation relative to the aircraft's energy level on the approach.

Now that kind of presentation would be used thousands and thousands of times because that is the number of non-stabilized approaches that are occurring in airlines' FOQA data.

The argument for AoA is not "natural" but is nevertheless a good one...the more info the better, but it comes with much more than just putting in the guage and both manufacturers and airlines are going to look at the cost.

It is the way this business is done, much to my (and most others who work in it) frustrations.

My comment about "how quickly things unfold" is an observation on the amount of time it took to lose control. Time is always "relative to perception and familiarity". When a pilot is highly trained, highly experienced and very familiar with his/her airplane, the flow of even huge amounts of information and lots of events flow much more slowly, perceptually, because the mind anticipates much more effectively and easily, (depending upon other factors such as distraction, fatigue) than if one is relatively inexperienced in such circumstances.

In terms of this loss of control, while it unfolded literally over a period of about 40 seconds, oddly that is tons of time to do something, but it is not a lot of time for assessment, discussion, action.

This is a really important point: Most things that happen in an aircraft that cause trouble or an accident take a few seconds and one has a bit longer for response. This is what training (and training and training) is for - to reduce the time needed to assess accurately and respond. The response to the UAS was instantaneous without, in my view, good reason to do so and without the requisite crew coordination. One simply never does that in a transport aircraft, period, unless it is a TCAS, GPWS warning. The SOP is, first establish control of the flight path, (in other words, don't give up a stable flight path for one that is unpredictable, uncertain, unannounced and unplanned); once control is assurred, call for the drills and/or checklists, all the while keeping a very close eye on the aircraft.

By the time the aircraft had stalled, they had backed themselves into such a corner of confusion that there were no breadcrumbs to get back to stable flight because they completely lost situational awareness even though the nose was pointed up, the stick was full back and the altimeter was unwinding at about a thousand feet every three seconds.

PJ2

thermostat

Thanks for reminding me about the A330 Instructors Support Manual link.

Man machine interface
 

Hi,

DozyWannabe:

What type of Stall?

SW was presented several times erratically, not adequately processed by the System.

Ok

Ok

Faulted at critical moments
After FUBAR "threshold"

IMO, the A/C (it's man machine interface) could (may be, should):

1) Provide an "immediate"* information (aural, whatever) to inform origin of trigger problem (actually a "frequent" and recurrent problem). It would have helped.

2) Protect* (limiting to REC MAX FL) from zoom climbing to the "corner" entering "the coffin" :} .It could have helped.

3) Provide* information on "dangerous trend" like AoA increasing at such rate. It could have (redundantly) alerted PM on PF "fatal" persistent NU.

4) Better Stall (characteristics) indication. Technically feasible. It could have "helped".

5) More elaborated Aural and Visual information to help "HF aspects" during "crisis". It could have increased their chances reducing confusion, stress, etc.

In this specific point we may mention: Antoine de Saint Exupéry's "It seems that perfection is reached not when there is nothing left to add, but when there is nothing left to take away"

Probably something that can be applied during extreme conditions in many designs.

Mac

PS

Man machine interface designers would have an opportunity after the results of the HF study of AF447.

(*) Cost: "near zero"

Temporary LOC of China 006
 

Hi,

Just remembering:

The "unprotected" B747SP AVERAGED ROD of 30,000 during 20 seconds.

They experienced as much as 5g. And practically lost left horizontal stabilizer / actuator.

:eek:

Mac

Dallas to Denver
 

Hi,

gums:

Why not use your car? :} Just 800 sm.

Mac

PS

My longest leg (in a Winnebago) was 1000 miles. By car is a lot easier. :)

99.9% or 99.99% ?
 

Originally Posted by PJ2
In the present system, 99.9% of flights work well with SOPs, CRM, appropriate use of automation (according to enlightened airline policies which permit hand-flying), but the loss of such skills is nevertheless no longer a blip but a trend



@mm43:
it is still very dangerous if PJ2 did forget a final "9" , and we replace thanks to your intervention, mm43, 99.9% by 99.99% : 1/10 000 means my children would have every 667 hours a :\ 4 minutes crash
Would you accept that mm43 ? no, no, no ...:=

And PJ2 would need 22 000 FT (or 35 000 ?) to push and recover, instead of 7 400 FT !!! no, no, no ...:=

roulishollandais

Hi,

PJ2
but in the millions and millions of hours flown in all types, lack of AoA has not been an issue until AF447
Indeed .. millions of flight hours and not get in trouble ...
This is always the case .. until there is a trouble ...
The cargo door locks of Boeing B747 .. millions of flight hours and not get in trouble .. until a door opened in flight and passengers ejected ...
Same plane type ... explosion .. cause problems in fuel tank
The B737 ... millions of flight hours .. until the rudder jammed ....
And in fact all the improvements of flight safety has always risen from the
similarly
Millions of flight hours with no problems .. and then .. suddenly the "apocalypse" and the eternal question:
Why ?

As an Anthropologist, jcjeant, I say without fear of contradiction, that in my experience, Man is the only sentient being who predictably misses that which is obvious.

and, sadly, sometimes deliberately.

roulishollandais;

You say, "And PJ2 would need 22 000 FT (or 35 000 ?) to push and recover, instead of 7 400 FT !!! no, no, no ..."

Sorry, where did you get 7 400ft from?

PJ2

Why?
 

Hi,

jcjeant:

Why ?

In all 3 cases you mentioned there was "tangible" failures, even on TWA800.

Now, if HF have to explain the crash we may say the causes are getting more "intangible"

Since the beginning BEA told the equipt. worked as designed.

:E ,

Mac