Dozywannabe; The take home message by management from engineering to the board room is that the glass is full. Now it's time to discuss board compensation.

@KMD - I say again, not in real-time safety-critical software engineering you don't. You're getting generic corporate/sales culture (which I've ranted about on this very forum at great length some time ago) and the work that many very talented and safety-conscious people have done to make modern aircraft as safe as they are badly confused.

BBB...this is a conversation between mature adults, both pilots. I'm not about to control what people do or say. I'm asking for a little forebearance in terms of the discussion, which, because you are a regular here, you know that the topic has been done, over and over again and gets us nowhere; the airplane is what it is and it seems to work well for those that fly it.

The thread was beginning to settle down into serious discussion, and I could see it taking off once again on another familiar tangent.

On your second observation re a "bus ain't a non-bus" , you've never flown the Airbus so you can't comment on it with any foundaton of knowledge or experience.

I've said many times here that where the airplane deserves critical assessment, and I've done lots of that over the decades, then I''m all for solid feedback based upon knowledge. But to be fair, and to be taken seriously in discussion, one has to go beyond what others say about the airplane, and know for oneself, the subject of criticism. The airplane is nowhere near as different as you have the impression, an impression gained through hearsay, not actual experience. The incident/accident record of the airplane is adequate proof of this.

The trim, and its availability to the pilots of AF 447, has been discussed at length as has standard responses to the stall. If managements of airlines, in their wisdom fail to teach about the airplane and, either through parsimony or the illusion that 'these airplanes fly themselves', fail run a sufficiently robust recurrent training program to ensure a depth of knowledge and that training precludes hand-flying and system knowledge, (vice Need-to-know nonsense), then that needs to be firmly resisted and changed. There is plenty of evidence now in place for change, beginning with those up front.

Dozywannabe; I think we're on the same wavelength. Risk management has a different definition in engineering and corporate culture. Engineers apply a risk factor to their equations to protect the applications of their work, MBA's try to see how much risk they can get away with before they declare bankruptcy and then create a new corporation to try it again. How many MBAs have died as a result of their aircraft management decisions? K

You're being a bit harsh. There are companies that DO NOT PERMIT less than full automation. Pilots can "fight" all they like and achieve nothing. Read a few pages back where Airbus pilots were being slapped if they touched the trim wheel.

Do you really expect a bright-eyed, bushy tailed sprog to jump up and down on a training course demanding more stall training in the supposedly uncrashable Airbus?

I'm still hoping some with Airbus A330/340 experience will be willing to discus their experiences with Alt 2 Law. This version of Alternate law is a 'Roll Direct' mode of operation.
How much training do pilots get in this mode?

If the aircraft was laterally imbalanced when you assumed control, wouldn't you have a heck of a time keeping the wings level? (Particularly if you are one of those AB pilots who routinely flies cruise with feet on the floor.)

I can see some serious potential for interference with proper pitch control until the aircraft is trimmed up with the rudder.

PJq - re your note to DozyWannabe is there a distinct display for the pilots when the plane is actually stalled rather than facing an imminent stall? If not, wouldn't that be a worthwhile addition to the software?

Capn Bloggs;

Yes, it is a bit harsh, isn't it. It's how this matter, (the intoxication with automation), which I and many here and elsewhere, have been writing about since the 90s, is going to get resolved.You're setting up a straw man argument and answering your own question. Of course I don't expect it. We both know that one person cannot change policies or world-views of large organizations (which depend upon "group-think" for continued existence), but I think it is realistic to expect the matter to be addressed maturely and through due process within the applicable groups and pilot organizations. There is sufficient material and evidence now upon which to base change. In fact, agree with the wisdom of such change or not, it is occurring in the US and in Australia; I can't speak for Europe.

Regards,

PJ2

That is why one need to be qualified to fly it!
But, you can also be sure that some are more qualified than others, same with any other type. In AF447 case, it is very likely that the PF was more qualified on this type and sector than the two other pilots taken together (including the Captain, also qualified for Caravelle XII, Boeing 737 and manual trim wheels).

Right. She stopped auto-trimming. It happens when the system believes the attitude "abnormal" (+30 AoA or speed below 60 kt, or pitch > +60... or because they used the manual wheel, or because the load factor was < 0.5 g... we still don't know yet! In any case, it is writen in the PFD "USE MAN PITCH TRIM" where you can't miss it (see PFD drawing above).

But the very relevant fact is that they pulled up during the first minute of their stall in order to reach such a THS setting. Then, they had two and half minutes left before impact and we still have not a single clue in order to understand at which point they finally acknowlegded their full stall situation.
After this point, I wonder if that would have made any difference if the trim wheel was auto or manual, that this aircraft was A, B or C...
Until we know more about what confused the pilots, jumping in and claiming that everything was linked with the trim wheel (they were not used to) doesn't make any sense. You won't use it if you dont think first that pushing the stick will help you to recover.

What do you specifically know about their training with manual trim or direct law?
Did you read anything about it?
How many pilots already stalled an aircraft without autotrim?
Quite a few, no?

Well, be sure that I dont know it myself but Airbus is stating that below 185 kt, elevator control is powerfull enough to override a jammed THS above +8 deg. After 185 kt, it is not so easy. Beside, while being at +13 deg, when those nose down imputs were applied, the AoA reduced... then, it was still effective to a certain point.
Yes, I'm from Toulouse, which mean that I prefer Rugby over Football (soccer). And that's just an opinion.
S~
Olivier

75 additional bodies recovered from Air France crash after 2 years
 

Unless I skipped a page somewhere, I've not seen this posted. Apologies if it has been.

75 additional bodies recovered from Air France crash after 2 years - CNN.com

This is contrary to decisions I thought were made weeks ago. Surely it's been posted and I missed it ?

It takes a hand in order to trim the rudder.

Your source is quite moot: this guy is a troll (ask him for full details and proofs about his claim). I don't know who is behind that but there is a bunch of guys around repeating always the same stuff which is mostly posted from one single source (internet) which belongs to some anti-airbus crusaders. Hence, this is fully circular as we always end at the same point, in this case, the very same url.

Takata
Yes, but before that, it takes a recognition of why the WING is heavy.

Hi Machinbird,
Oscillations doesn't specifically mean an heavy wing after switching to direct roll. Read the part of the FCOM I posted above and you'll see that it is mentioned that you may have to re-trim the rudder in order to stabilize your roll axis.

Auto trim and HUD displays
 

@ Galaxy:

The Viper "auto trim" seems identical to that of the Airbus except for the bank angle and pitch attitude corrections. Actually, not a bad idea for a heavy, but a bit clumsy for the fighter plane requirements. So we trimmed for gee as set using a trim wheel or the thumb hat switch on the stick ( HUD showed instantaneous gee to a tenth of a gee). We could trim for zero gee and during a fight let go of the stick and get less induced drag to "extend" or gain energy.

The 'bus computers add to the basic one gee gee command for a bank angle. So in 30 deg of bank it trims for 1.15 gee or so. Same for pitch - a 30 deg climb would be trimmed for about 0.87 gee, otherwise pitch would continue to increase if still trimmed for one gee.

Neither the Viper or the 'bus trim for attitude, best I can tell from the manuals.

Some folks seem to misunderstand the airspeed/altitude displays and such when talking about the HUD.

BARO DATA IS NOT USED FOR THE FLIGHT PATH VECTOR in any application I have looked at except a "poor man's" FPM (flight path marker - that little airplane doofer)

What it is used for is the speed/altitude part of the display - those "thermometer" doofers on each side of the display. Same for vertical velocity, which could be baro or inertial, depending on a switch. Some planes only show baro VV. Some planes can show radar alt versus baro, and the beat goes on.



I read a symposium presentation by some dude about the Airbus HUD installed in some variants. Thing sounded like a poor man's HUD, and I can't understand a modern plane without a cosmic, large field-of-view HUD, especially for landing and takeoff. Ask 'bird about a night cat shot off the boat without a HUD. The FPM showing your vector was above the horizon was very "comfortable". It also helped getting back onboard at the very end of the task, although flying the meatball was as good or better.

In the AF447 situation, an inertial FPM would have been invaluable showing the crew their flight path with respect to local level. After all, you can have the nose up at 16 degrees and still be falling like a rock! Think I saw that number last week.

HUD "pitch lines" are also easy to read and use. So setting a 3 degree glide path or climb is a no-brainer.

PLZ try to watch the shuttle landing in an hour or so, and you can see a real HUD in action.

Otherwise, I'll hunt down some You Tube sequences to show mine. Haven't digitized my LEF failure landing but it is a good one to see how the thing helped me land.

Thanks, gums I had read a magazine description of the Airbus and Falcon 7X FBW system as being flight path stable, that is, it holds a flight path, but expressed as G-stable makes better sense.

I used the crude HUD in the A-10 and loved it, as a new toy. Now, in the Global, the HUD is wide-angle, has EVS, and is invaluable for all flight regimes, especially night visuals; using EVS, figuring out if you will clear that cloud deck; single engine work.

Takata, Can I have the pillow you sleep on?

From the brief description BEA provided, the guy flying was bombarded by more stimulus in his few minutes holding the stick than most drivers get in an entire flight.
Do you really expect him to recall the words from FCOM in that short a time period unless he actually practiced such an eventuality as he experienced that night?

Everyone has been real quiet about their experience in Alt 2 law except the test pilots.

Do you think any really constructive training was accomplished in Alt 2 law prior to this accident? (And by really constructive, I mean the kind that makes you both think and sweat.)

options
 

Hi this is a question from a lay point of view,
Tim Vasquez's weather analysis seems to show that the flight passed through a smaller portion of the storm came to a clearing which perhaps caused the captain to think they had cleared the storm? when in fact they were just about to enter a larger portion which then caused the pitots to ice up causing the autopilot to kick off. Would the captain have gone to take a rest if he had known the larger part of the storm was yet to come? — and if not, why isn’t there more accurate information in flight at night when they have no sight visuals? Is it true that it is easier to know with greater certainty about storms when flying over land vs sea, because there are more sightings?

The records seem to show that the flight just before and just after chose not to go through this storm, but around. Is there any truth to a report I read at the time, that this flight (in trying to save gas) was cut so close they didn’t have the option, in terms of enough fuel, to go around the storm?

Just wondering.

It seems that if the captain was on deck, by this remark,"This is a stall. Reduce power and nose down!" he might have been able to save the flight, unless there are other factors impacting the situation which aren’t clear. I think from the discussion here there are far too many reasons why the situation might have been confusing to assess in the few minutes they had once the chain of events began. Some might know what to ignore and what to attend — though certainly having the stall warning go again when the needed action was begun certainly was no help in the short time to assess and respond. Clearly changes are needed to avoid many parts of the sequence which caused this — the freezing of the pitots, perhaps better weather analysis or clarity of weather conditions, not ever assuming in training that basic air tools would never be needed because a computer system now takes over those roles, when that system can turn off and require pilots to fill in at any time (or at least, always at a time unexpected), with pilots having both a need to know all that the system is doing for the pilot and to have it spelled out quickly and clearly, as well as an ease and comfort with all these tools and sequences, so life and death decisions can be made with clarity and accuracy in unexpected circumstances on what might otherwise be a routine flight. Since the flight just before and after diverted — was there pressure to go through weather unnecessarily?

If there is any question about conditions, is there truly the free choice option to go around the weather, as did the flights just before and after, rather than through (to save gas or time); — or at the least — there should not be any pressure to make such a safety decision based on gas related issues, if there is any truth to that (?) Was that an impact here to not simply choosing to be safer and go around?

[Should passengers be putting more pressure on airlines regarding weather decisions to give pilots more breathing space and freedom to make needed choices? (or at least not to be pressured to go towards questionable conditions, if this is indeed happening?) Is this an issue?]

At each of these earlier levels, the flight would never have been put in this situation — on the other hand, there are so many factors impacting the pilots’ decisions once the sequence began, it seems these problems simply need attending to and if not this flight, another would have brought them to the fore.

I wanted to mention these less technical observations, simply because as a passenger now, I’ll always wonder if simple logic is being waved or honored, not so much by pilots at the time, but the myriad of technical choices made beforehand — which perhaps is at the heart of much of the concern about this loss.

Please forgive the very lay point of view, but profound interest to this sad incident.

I understand that the NPF says, "we have lost the speeds, alternate laws then"

According to the checklist, I don't get the point why the PF, which was FO No2, the one with the least flight experience, pulled the side stick.

As we know from the FDR data, the climb was commanded and not coming from an updraft turbulence.

By pulling the stick he induced a vs of 7000, which exceeds the max of the aircraft by 1000 ft/m. 6000 is max.

Secondly, the A330, same as the A320 are equipped with two GPS systems apart from the pitot tubes. Even if all of them have failed, the still could verify GS on the ADIRS panel overhead and in MCDU.

He pushes the throttle handle into TOGA which is according to the checklist alternate at that time. Somewhere I read that this is revised now.

I exercised this yesterday on an A320 sim @FL360. TOGA will not initiate a climb at 7000 ft/min. And he PF managed to reduce to 700 ft/min as per FDR data. Why the heck would he still climb. We are not talking about a propeller engine that generates dramatic updraft at full throttle.

CB ceiling was up to FL550. Clearly not over-flyable. I really don't get the point why the PF pulled on the sidestick.

I did already once a deep stall an the A340 sim at FL390. I am was unable to recover. I was falling out of the skies. No matter how far forward I pushed that stick, the nose never got down to recover as I can do on the F18. My deep stall, was nose up with about 20°

Off-Topic, because was asked.
Now for all those asking about my flying experiencing. I have only Level-D sim experience and MS Flight Sim. I have 6 hours on A340 Level D and 2hrs on F-18C Level D. I am not a pilot. And realtime flying experience on MS FS about 4000+ hrs A320/A330.

flawed outlook
 

An observation, and a question:

By arguing against further Automation in Aviation you are inadvertantly making the case FOR further automation in avation.

To suggest automation is the wrong direction means that you have chosen to ignore the bigger picture - the overall safety situation - and, by doing so, have behaved in a flawed way, a flaw that wouldn't have been displayed in the behaviour of, for example, a machine.

To put it another way, by allowing prejudice to influence your opinion on automation, you are actually proving that automation is ultimately the only answer.

The only question is, therefore, will you realise this and choose to work 'with' progress, thus maintaining an input (pun intended) and helping to shape the future of aviation, or will you continue to resist progress, thus act as a catalyst for the very thing which you resist?

Ventus45 wrote:

Who are your calling "your honour"?

The A330/340 level-d sim is at least as good as the real aircraft when it come to manouvers and flight controls. Yes, agree. Maybe forces and turbulences have differences compaired to the situation you might encounter outside in real live. In the end it is a flight deck sitting on hydaulic legs.

I was not trying to blame the PF at this stage. I did not say hang him. All I try is to figure out what made him pull after disconnecting the AP. But obviously there is no real data around to get a conclusion on this.

Yes, maybe BEA will release at some point further details of the FDR and CVR. A reconstruction of the instrument situation would be interesting.

So you know that the A320/A330 sim you have used has "valid" data for deep stalls?

Not exactly sure how the sim can be better than the aircraft, unless it is used as a toy!

No, sure. I was not intending to refer to the deep stall. I was more related to Ventus45 saying that the SIM is not good enough.

The SIM can simulate failures and things alike, no? I can stall the SIM and it happened. Don't know why it happened but anyway I screwed it up at that point. Never analyzed it. I was there for fun. Remember?

At least I can say that the Airbus will not pitch up 7000 ft/m if protections are active. No matter how hard i pull or push on the stick.

I am very unsure if the were in ALT1 or ALT2. Based on the ACARS, with two ADR failed, it's supposed to be ALT2.

Can you recreate the 2000 A340 airprox zoom climb from FL360 to FL384 at up to 6,000 ft/min ?

What protection will stop the aircraft climbing at 7000fpm?

Under Normal Law, there is a pitch attitude, as well as a bank angle protection and some other too, like a-floor, ...

Input on the SS that exceeds the Normal Law parameters, will not be executed by the flight control computers. Thats my easy way to explain it. Maybe someone can explain it in a more technical correct way.

Stalled AF447 did not switch to abnormal attitude law
By David Kaminski-Morrow


Investigation into the accident sequence of Air France flight AF447 has revealed that the Airbus A330 did not enter the abnormal attitude law after it stalled, despite its excessive angle of attack.
The abnormal attitude law is a subset of alternate law on the aircraft and is triggered when the angle of attack exceeds 30° or when certain other inertial parameters - pitch and roll - become greater than threshold levels.
Alternate law allowed AF447's horizontal stabiliser to trim automatically 13° nose-up as the aircraft initially climbed above its assigned cruising altitude of 35,000ft.
The stabiliser remained in this nose-up trim position for the remainder of the flight, meaning that the aircraft would have had a tendency to pitch up under high engine thrust.
Crucially the abnormal attitude law - if adopted - would have inhibited the auto-trim function, requiring the crew to re-trim the aircraft manually.
After stalling, the A330's angle of attack stayed above 35°. But while this exceeded the threshold for the abnormal attitude law, the flight control computers had already rejected all three air data reference units and all air data parameters owing to discrepancy in the airspeed measurements.
Abnormal law could only have been triggered by an inertial upset, such as a 50° pitch-up or bank angle of more than 125°. "That never occurred," says French accident investigation agency Bureau d'Enquetes et d'Analyses.
The BEA is still attempting to explain why AF447's crew failed to rescue the aircraft after it climbed to 38,000ft and stalled. The pilot's control inputs were primarily nose-up, despite the stall condition.
There has been no indication that the aircraft switched into any other control law, other than alternate, during the accident - suggesting that auto-trim was available throughout the descent.
Failure to realise a need for manual re-trim was central to the loss of an Airbus A320 over the Mediterranean Sea about six months before the AF447 crash.
The auto-trim had adjusted the horizontal stabiliser fully nose-up but, during a flight envelope test involving near-stall, the aircraft switched control laws and inhibited the auto-trim.
Without manual re-trimming, the aircraft pitched up sharply as the crew applied maximum thrust. It stalled and the crew lost control.
In its conclusions over the accident the BEA highlighted the rarity of the need to trim manually, which created a "habit" of having auto-trim available made it "difficult to return to flying with manual trimming".
"One of the only circumstances in which a pilot can be confronted with the manual utilisation of the trim wheel is during simulator training," it said. "However, in this case, the exercises generally start in stabilised situations."
In the wake of the A320 accident, near Perpignan in November 2008, the BEA recommended that safety regulators and manufacturers work to improve training and techniques for approach-to-stall situations, to ensure control of an aircraft in the pitch axis.
Stalled AF447 did not switch to abnormal attitude law

Sensor validation/ MartinM.

It will certainly climb at 7000'/min if its in a sufficiently powerful updraft, indeed it could be hard to stop it doing so.

That climb must have been a combo of pilot input, weather and maybe aircraft input if speed too high.

MartinM,

I think you'll find the aircraft can climb at more than 6000fpm and remain in normal law!

Yes, agreed.

Maybe, yes.

ACARS Messages – time-stamps
 

Salut encore takata,

Am catching up, currently only 40 hours behind in this plethora of mess ages...

Re the time-stamp on the ACARS warning/failure messages:

is it your understanding that the timing is to the nearest whole minute? For example, does a time-stamp of "0210" mean that the event was generated between 02:09:31 and 02:10:30 (inclusive)?

Up until I read one of your posts this week, I was assuming that a time-stamp of "0210" would mean that an event took place between 02:10:00 and 02:10:59 (inclusive).

On the off-chance that you spot this post, ;) I would appreciate your clarifying this important (30-second) ambiguity.

Hi Chris,
Nice to see you.
Yes, the "nearest minute", is what I thought:
02:10 = 02:09:31 - 02:10:30.

But after reading you and checking again the French report it is writen: "précis à une minute près".... not what I remembered "à la minute la plus proche".
Hence, it is more probably what you said:
02:10 = 02:10:00 - 02:10:59

Hi,

About all those posts on "blaming the pilots or not" "blaming the constructor or not" "blaming the airline or not" (on the basis of available fragmented informations so far ..)
A straight report will be
If the pilots are in fault on the AF447 ... the case is simple and the final conclusion of BEA will not contain any recommendations concerning the aircraft.
If the pilots are not at fault .. and so it will be recommendations concerning the aircraft
But I'm sure it will be not so straight ... and certainly it will be recommendations about the pilots and airline (training SOP .. etc...) and recommendations for the constructor(s) and recommendations for the regulators
Seem's to me a usual and honest scenario and it will be no different for the AF447 case.
So .. it will be also many food for the court of justice
Nobody will go out white from this accident.

Stalled AF447 did not switch to abnormal attitude law
 

Tubby:

From the BEA report:



More questions to answered by BEA!!!


From the AMM:

From the FCOM:

I don't see this statement from BEA - not even from an alleged "source close to the investigation". About as reliable as the media reports who was PF in which seat? The BEA report states that the "The inconsistency between the speeds displayed on the left side and on the ISIS lasted a little less than one minute" and 2 out of 3 means they agree - even though we don't know what RHS was displaying.

Maybe possible abnormal attitude law not triggered because of the cross-link between real and indicated airspeed and AoA - at high AoA IAS much lower than TAS, and low IAS suppresses use of AoA?

Takata, it may take a hand to trim the rudder, but if you are a pilot, you are taught to fly with your feet. (I understand that some people are taught to stop doing that ... ) The point of the trim (particularly if we are discussing manual trim versus auto trim) is to set a new rudder position so that you don't have to keep making smaller and smaller inputs.

From the diagrams I have, there are rudder pedals on the Airbus 330.

Using your feet to move the rudder is a skill taught from Hour Zero in anyone's flying career ... a skill that appears to atrophy with disuse. :mad:

Hi tubby,
Thank you for posting this. IMO, it changes everything.
Their source is the BEA and I presume that it is a very serious matter if the BEA informed them at this stage of "no switching to abnormal attitude"= no trace of it in the DFDR. Those technical informations are too precise for being another "rumor".
It means that autotrim was available all the way down.
It means also that:
a) either they never really pushed the stick in order to recover as the THS did not move back.
b) The THS was jammed (but they should be able to say it).

Consequently, a) being much more probable, it would also mean that they never acknowlegded the real situation (being stalled).
My opinion is that one may make a serious mistake (bad reflex, etc.) but it doesn't fit with 3 pilots confronted to a situation lasting four and half minutes.

I'm pretty convinced now that there was an unknown factor involving instruments that fooled the PF, hence more specifically the Right Hand Seat which is feeded by ADIRU2. Also, by deduction, the pilot flying was David Robert, 37, with 6,547 flying hrs including 4,479 on type. He was by far the more experienced A330 jockey on the deck and was PF from take-off. His reaction was immediate, he was not asleep, and he should have been fooled by something.

Yes. And those pedals are used as wheel brakes too, on ground, of course ;)

Rudder Trim, is a small knob on the center pedestal console, while elevator trim is a large trim wheel besides the Throttle.

Hi Lonewolf,
Your comment is irrelevant with the point I was making about trimming the rudder for addressing the sensitive roll axis being direct. It takes a hand, nothing more. Read again what I was talking about before jumping in.

Yes, Martin, I also gathered that from the cockpit and flight controls layout available in the public domain.
takata, I'll suggest to you that pilots know that because that is part of flying.

The mental and congnitive process, when you are doing this on instruments (which I presume AF 447 crew were, as it was night and the Wx was bad) is to set an attitude in balanced flight and trim to hold that attitude in all three axes. (Plural of axis)

What I was taught and used to teach was to trim nose and rudder first, aileron last, to avoid cross trimming, but such technique is probably model dependent.