I think jcjeant has a strong point here. With FBW, training "can be" shortened, it inspires confidence, sometimes without the mode to back it up, (BOAC), It is seductive in that "stable flight" is actually cheaper than manual (in the long run), etc.

For me coffin corner is all vectors of flight are maxed, and cannot be stretched, or modified, without upset. Too fast? Pull up. Can't, Stall. Too slow? push yoke. Can't, overspeed. Want to turn? Sorry, drop a wing and roll into a spiral. Etc.

The very best format for avoiding problems with CC is either one, FBW, or Conventional. The edge? Neither one. Where a pilot is not as precise as Otto, neither is Otto aware of the potential disaster, just as A Prot can be compromised by another "protection". "Don't touch" is a human skill, evidently not so much with Otto, except when it gives up on the a/p, and runs for cover. (447)

The word "Protection" I find offensive. Can we lobby for a refit of nomenclature?

What was there to learn before that we/they didn't already know (then)?

• Sensors can fail (especially if damaged in maintenance) - already known.

• Water in AOA sensors can damage them - known, but maybe to be sure, we should ensure that they are to be covered in washing procedures (oh, already done). Note that we also already knew that remembering to tape sensors up, but forgetting to untape them is also fatal, and that these sort of maintenance failures affect both FBW and non-FBW aircraft. Fatally.

• Triple-redundant system cannot cope with multiple sensor failure - known mathematical fact (see previous discussion on thread).

• Alpha prot will not activate correctly in the event of multiple AOA sensor failure - known consequence of above. By design (and cannot be designed any other way).

• Sensor failure can be identified by both a check flight and "maintenance records" - believe this is exactly as designed.

• Aircraft will fail the alpha prot test on check flight in the event of multiple AOA sensor failure - as designed.

• The failed test will not have any other consequence for test flight (not even a stall warning) - which is as per the design of the test procedure.

All these are still known, still valid - even the last one. In this case the crew conducted a different and far more dangerous test in which the inevitable consequence of a failed test was a stall (or approach to) with trim up, which it appears they did not know how to recover. In the light of the latter point, the inevitable consequence of a failed test was a crash.

Why test a protection system whilst relying on it to save you ? - better to not test it at all and hope it works, you'll live longer (on average, whether it works or not).

Maybe we should issue a new procedure that says "for test flights, follow the test procedure, it's really important" (and same for maintenance). Will that fix the issue of people not following the procedure ? Will they learn when they didn't before ?


Finally, on learning, the fatal LOC, the final hole in the cheese, was failure to control pitch / trim, in (approach-to) stall. When will we learn that this issue is not a FBW issue ?
Quoting the AAIB (regarding the 737):

This isn't the only other incident either. There will be more if people don't learn, and mis-characterising it as a FBW issue may stop people learning.

Coffin corner theory was de-bunked extensively on the 447 thread.

Margins may have been insufficient when you add in flying through a large CB... but that isn't "coffin corner".

In transport jets it will be autopilot that flys it in cruise - whether the jet is FBW or manual. Current autopilots are not sentient and do not have the concept of the plane being "easier" to fly, so FBW or manual makes no difference.

U2 flies far far closer to coffin corner than commercial jets, and it is not FBW (I think - obviously I do not have U2 design documents...).

The U-2

Is an odd duck, light, very high aspect ratio, and plenty of Power/weight, it routinely operates at very high altitude, frequently nibbling for hours at Stall, overspeed, upset, etc. Coffin Corner is quite familiar to its pilot. It is common for overspeed and Stall to be separated by less than two knots. Not really an accurate comparison. I don't recall in the 447 thread, (either one) where CC issues were completely rejected?

rgds
bear

Such has always been the case. One additional thought: when you design out (or "protect" from) the simple failures, you are inevitably left with the complex and "interesting" failures (and typically with a more complex system).

Not to blame the mechanical, but understand the consequence of progress and complexity.

No, but intended to disprove theory that it is FBW that allows you to fly closer to the line - since it doesn't have it.

I do recall posts that actually calculated the margins based on the reported weight, fuel, height, flight-time etc., and came up with reasonable numbers.

That does depend on what you define as a reasonable margin and what is CC, and what is reasonable in a normal cruise may not be good in a CB with unreliable IAS. On the other hand, both CBs and AS problems can and have killed, without needing help from CC.

Only the recorders will tell us (and sadly I don't think they'll be found anytime soon).

Well, CC is a stretch as re 447. Stall and upset are not, and the U-2 can be flown (is) manually on the edge. It takes a lot of training. Not long ago, a U-2 pilot did something most pilots would have said was nearly impossible, he Stalled, and Spun, while turning Final at Beale. He crashed in town, I think, but with the lift the a/c has, and the glide, there is no excuse for stalling a wing. Especially when one can control the a/c at the razor edge in thin air. Beale is virtually sea level, and the weather was nice. This aircraft gives up and drops a wing on the Runway slow enough for E-1's to run along it and grab the tip, to keep it from scraping concrete. Landing is actually the most difficult manouver in the a/c's quiver. It was designed w/o focused attention to landing, other performances were critical. It simply does not want to stop flying.

FBW actually does make possible flight beyond the safety limit for manual control. It isn't advisable, but as BOAC has said, it promises alot. At the edge of a Stall, the FBW machine won't burp, or sneeze or suffer nervous muscle contraction. Manual limits are grosser, this is why I think numbers can be calculated for this test, and flown down to prot (calculated prot). The computed number is accurate, and should be relied on, but the crew here did not take the time to calc this low speed number.

It really is as BOAC says, and I don't think he would disagree that FBW can glitch, meaning the pilot must be schooled in Glitch response. I disagree that the glitch is in any way different from any other machine. The fault lies in unjustified reliance on the machine, based on its representations, instead of scepticism, and proper training/response. IMO.

bear

AF447's CC was at FL450. It was cruising at FL350.

regards,
HN39

I think bear and I are pretty much on the same sheet - my view is that:-

1) There are software deficiencies which need to be addressed
2) There are training deficiencies - ditto (see my thread about computers on Safety forum)
3) There are deep-rooted misleading 'salesman's falsehoods' which need to be eradicated from human memory in conjunction with 1 and 2

I trust I am not mis-understood here - I definitely see FBW and software assistance as the logical and safe way forward. I loved the 'automation' that gradually eased my work-load (but sometimes increased it!). It is the road that we have been seduced into following that I take issue with.

..and can we PLEASE stop talking about 'coffin corner'?

I remember from my tenure on a FBW Airbus type (fairly early days) some startling isues which would corroborate with previous posts.Firstly ,very poor training from instructors with limited or no time on type.Secondly,far-fetched propaganda from Airbus hq which did not fit the facts.Not disputing that the Airbus FBW types are not fantastic feats of engineering but there are and apparently remain , traps for the unwary.My view became that any aircraft that can cause the demise of the airbus chief test pilot (RIP) can do the same to me with ease.

Cheers

olster

To be fair to AB, the demise of its chief of test is most likely statistically more probable than a low time line pilot. The line pilot should be very familiar with the fat part of the Bell curve re: handling. The Test Pilot flies in the corners, challenging the a/c's limits, virtually daily. He has a different mission, and it is not without enhanced risk. Insurance is more expensive for him for a reason. This is not to say his job is dangerous, only that he encounters more risk. His skillset is different, not necessarily "better". IMO

In this accident, a "test" was undertaken without the numbing prep work, and executed by a pilot who was out of his domain. The instructive part of the accident has to do not with AB "problems", nor is it to do with poor pilotage. It shows the results when preparedness is sacrificed and substituted with overconfidence that had no foundation in fact. imo

bear

I think in and of itself, flight is quite simple. I have the persistent feeling that Captain Hank of old, the guy who flew water a/c through 747s for PanAm could fly the AB or the Boeing with equal confidence.

Let me be honest here. I think in some cases, perhaps in many cases, complexity is devoid of return, and sold for its profit or perceived benefit. I try to put Hank in each of these accident circumstances. 447? Switch off a/p and hand fly. Unreliable a/s. Pitch and Power, and by the way, where is the A/H? Alpha Prot? I need a box to "save" MY a/c from upset? Etc.

If an a/c is perceived to be superior, Fine. Don't forget to show its pilots how to manage it in difficulty. Don't make the goal transcendence above the pilots. No machine is perfect, if it can fail, it will. Don't potentiate a surprise when the a/c does something "impossible". Don't let engineering ego kill people. False confidence is a poor substitute for preparation?

bear

Fair enough
 

...have taken the hint:ok:

Bearfoil:

This thread is now over 1500 posts long, mainly with people pontificating about automation. Lets get back to the facts as revealed in the report.

The crew attempted to conduct a test at low level despite the test specification warning that the test MUST be carried out above 10000 ft AGL because failure could result in a stall which could take a lot of altitude to recover. The test failed. The aircraft stalled. They had insufficient height to recover.

FBW is irrelevant. Automation is irrelevant. They screwed up by also having maximum nose up trim and TOGA power applied. They put themselves in a situation where ANY aircraft (except possibly an AN-2) would have killed them. Stall recovery is a fundamental piloting skill, prompt and correct recovery action might have saved them but the ground was coming up fast.

Time for stall recovery to be a mandatory currency item at every simulator visit ?

Stall recovery
 

False.

A. They flew into a full stall, with quite a wing drop and recovered
They recovered from that stall, loosing 1.000 ft. or so (one thousand, not ten). Speed was up, wings were almost level, they were climbing back to initial altitude. For a few seconds, everything was looking as being under control. They used quite normal recovery actions : stick forward, "throttle" forward. Student pilot skill.

Next immediate required student pilot skill was to trim forward.
This is were the crew first failed.
Why?
Because :
- They were not used to operate manual trim, since AB is on auto-trim in normal operation. Thousands of flying hours without ever touching a trim switch or a trim wheel ... So the habit (and the skill) of using the trim "manualy" was lost.
- They were not aware (obviously) that the auto-trim feature was inop.
I see here a systemic failure :
- automation set one step too far, reducing piloting skill below that of a 5 hours student pilot.
- lack of pertinent training

When the trim upset put the aircraft in an unusual "nose high" attitude, the skill required to recover was at the commercial pilot level : "recovery from unusual attitude" (visualy or by instruments) :
- roll to high bank,
- reduce power/thrust
- and level off carefully when the nose start dropping

This requires training, and recurrent training, and specific training on each aircraft type. This requires good pilots and good instructors and good training programs.

It seems to me that the lack of flying skill was one big factor in the fatal issue ...

Strange, when one consider the captain was qualified as TRI/TRE ...

Bis 47, a good analysis, but not ‘crew failure’ … … a deviation from expected behavior, the circumstances of which provide many safety lessons.
Expanding a few of your items:
they were not aware … auto trim. Apparently so, but the crew may not have considered that auto trim would/could be inop – poor knowledge, failure to consider alternatives, or failure to recall valid knowledge in the situation.

The systemic failure perhaps includes the lack of guidance on flight testing / system checking. Although AB had guidance would an operator have a copy – it would be prudent to request guidance.
Did the national authority have guidelines or even hard boundaries – the UK CAA did, perhaps these should be used by EASA.

The missing ‘flying’ skill was the ability to think about the test and issues which were to be checked; a TRI/TRE qualification or thousands of hours does not automatically infer an appropriate mode of thought – to see the bigger picture.
It’s not the skill in recovering from a post stall upset, it’s the skill of avoiding a stall or the post stall consequences which is important.

bearfoil provides a lustrous view of test pilots (#1503), but it is the provision and use of the skill set which aids safe operation. A tp’s ‘flying’ skills involve the same human thought processes as available to all pilots. These skills might be used more often and also in non-normal scenarios; tp’s are taught to think that way.
When and how are line pilots taught to think?

The lack of pilot intervention and using basic stall recovery procedures has been repeated over and over on this thread. It is always the pilots responsibility to make sure the automation is doing what he wants, if it isn't just take over manually. These guys didn't.

Prevention, cure and judgement
 

Prevention is obviously of prime importance.
However, by disregarding the "cure" side, one let the last hole open (in the chain of failures).

That is a good question. Some answers :

- Pilot selection : select people with good education, check theyr "thinking" ability. This is not in phase with the current philosophy of selecting "standard" (average) personnalities. One of my best student was rejected for being "too good" at thinking. He was also very, very good at "handling" the controls ... (Got a job in a less pretentious company without problem.)

- Continuous education : lectures, reading accident reports and analysing failures, recurrent training with the appropriate briefings and debriefings ... From first copilot job to captaincy, many many opportunities arise to learn facts and to learn thinking, decision making etc; still a few years and many more opportunities before becoming an TRI. At the TRI level, scenario based training make it mandatory to think and to teach thinking ...

That is theory ...

I'am a strong supporter of the thinking pilots, and of all the means to improve thinking ability. It is a long quest, and if you care about it for your children or grand-children it is a long term investment ...

In the real world of the airline Industry?

I'm not sure that the management does care. Including at the flying department managment level.

Finally :

Maybe the captain was a good TRI/TRE with great thinking ability. And he was just "not in the mood" that day. Brain performance reduced for any reason. Human "thinking" failure ... That is. Brain power more often than not is a weak link in the chain ...

I keep thinking that in a stressfull context, basic piloting skills - skills that do not require thinking - can save the day.

What? This is a new one, coming out of nowhere. What sort of software deficiency is proposed? Where did any software fail to fulfil its requirements?

PBL

Bear -good points and very well made.I certainly understand that a test regime has different risk to line operation.Perhaps,I was guilty of a glib remark ref the tragic accident of the A330 at Toulouse.However,I still would say that there are(or certainly were) traps for the unwary in the Airbus fbw series which were not instructed well,if at all.I appreciate that this may or may not be relevant to Airbus test flying.

Cheers

olster

The picture I have from the report is that trim automatically went nose up, to the stop.
The pilots were used to depending on auto trim, and didn't think to consider the antagonistic Pitch force thus provided against their wish to drop the nose.

A general concern might be that in slow flight, autotrim (Auto Pilot?) might be unnecessary. The Bus has powered controls, and has a fine "touch" relative to Pitch, at any speed, so why not set Trim at the neutral set, and rely only on elevator, or elevator plus an "articulating" HS? Trim used to be simply a setting that lessened a pilot's effort at the stick, instead of a fully integrated "Variable Incident HS". Whatever the concern, here the trim was in what used to be called "runaway", relative to the pilot's baseline Pitch awareness. As BOAC has said, automatic flight is a boon, an enhancement (great word), but if something gets pear, the pilot needs to know the "mood" of the a/c, and immediately. Any hesitation in alert may cause an unproductive "solution set" in the FP, and want "unwinding" as The Pilot "finally" "gets" the situation. My sense of the AirBus is that it is finely tuned and capable, and resists rapid and large movements, that it is "uncomfortable" in the "unusual". Why wouldn't it be, it is designed for the normal flight. If flightcrew are not well trained in its behaviour at the edge, perhaps the "edge" in a commercial turnover should be explored by the Manufacturer's test flight personnel. The focus of this airframe is docility, and efficiency, and Safety. If it is trained to these goals, and unusual Attitudes and Stall are not "possible" such that these are not trained, a casual decision to test slow flight and protections at very low altitude would be (should be) non existent? I think BOAC has the upshot of this accident fully nailed down, aerodynamically, mechanically, electronically, and even politically.

bear

More simply put if your aircraft is stalling, add a bit of forward pitch and add power so you don't pitch up. Guess that is too simple. Sorry. It always worked for me instructing in C 150's. Also works in B757's.

Grrrrrrrr.......:ugh:

Increasing power is a VERY foolish move in a jet with engines under the wing. This causes a pitch-up moment which increases AOA, making the stall worse.
This has been a contributing cause in several fatal accidents.

- have you thought of telling the aircraft manufacturers about this - they do not seem to know?

Yes ... pitch + power/thrust management seems however a little bit more tricky in real life when :
- close to the ground
- loosing speed due to windshear
- developping high sink rate

This is, I think, the most common stall context in line operation.
C150 or Boeings.
Full power/thrust is then required to recover energy asap.
Lowering the nose being a very limited option.

So the "standard" recovery practice : full (TOGA) thrust, while keeping the aircraft at the edge of the stall or, most commonly at the stick shaker limit. It works ... (Except on ww2 fighters where full throttle at the stall would snap roll the aircraft ...)

Trim is not mentionned here, because :
- the aircraft is normaly on trim for a speed higher than stall speed
- the aircraft would remain at max lift CL for a while ...
- it is normal flying skill to trim as necessary, isn't it?

Basic flying skills ... rehearsed again during type rating and recurrent training so as to be aware of and familiar with special - type related - idiosyncracies.

Is it too much to require from a type rating program to discuss and train in all aspects of stall on type? Including of course malfunctions of automation?

Any flight has the potential to flirt with the limits, without being called a test flight. Isn’t it one main reason how Airbus justified the protections ?

Full back stick is the Airbus procedure for GPWS warning … How would you justify the system did not deem as necessary to advise the pilot it was not the best idea on that day to blind fully trust its system ?

Simply put, probability.

The likelihood of circumstances requiring the protection function to work is less than P=1. Therefore some failure rate of the protection system is acceptable. But for circumstances where you are deliberately testing a protection function, you can't take credit for the probability of the circumstances, because they are certain.

Its the difference between potential and certainty.

To take a different example - any takeoff can become a high energy RTO. The risk is known and managed. But a deliberate high energy RTO for test purposes is managed rather differently - fire trucks on hand, crews with protective gear, specifically briefed, and so on. Because now that the RTO is certain, the normal safety measures - having a fire truck somewhere on the airfield, for example - doesn't cut it. We need it right there.

Same for protection systems. Their normal reliability requirements are a function of the probability they will be required.

Bear in mind, too, that the design was operating believing it had one failed sensor (of 3) and with two remaining, that should be enough redundancy to complete a flight, since the chance of the next sensor failing combined with a "required protection" condition is acceptably low. In service.

MFS,
My position is that everybody has to learn something from an accident, and the Manufacturer is not to be excluded.

It takes absolutely nothing to trigger an AOA DISCREPANCY ECAM MSG meaning :

"Eh guys, our AoA probes disagree, the probabilities are on our side, we believe the faulty probe has been identified and you can resume normal operation. In the meantime, as we have been proved wrong a few times already ... if your intention was to test the system today, don’t do it, and if by adventure you was unlucky to need maximum performance of the system, don’t rely too much on our protections today, but simply use your own abilities a bit like if you were flying a 737"

Don’t you agree such message could positively influence a crew and therefore improve the level of awareness and safety ?

Yes, a missing piece in the design. An inadvertant omission, to be sure. What good does it do to understand a problem if it isn't passed along to the "caretaker"?

"My way or the Highway?"

In circumstances where a single discrepant probe has been discarded and the system now relies on two, I doubt such a message helps. The aircraft I am most familiar with only has two AOA probes to start with, and we need those at least as much as airbus does theirs. And except in this very odd case where the functional probe has been dropped, if the message has no crew action required, why post it? It certainly shouldn't be an amber Caution, as you colouring would suggest. At most it'd be a white/blue advisory, and I really wonder why we post those, since we are allowed no credit for them in considering crew response.

I agree 100% that the manufacturer needs to learn from every action; none of us take accidents or incidents to our products lightly. In this case, though, and as I alluded earlier, its unfortunate that Ab don't appear to have a scheme to determine that a probe value is valid - in the sense that there is no known fault with that sensor - but still likely erroneous. In this case, anyone looking at the DFDR trace sees those completely static AOA values with changes in speed and configuration and a big red light goes off in your mind. The system monitoring the AOA data could have done the same thing. "Before I vote out bad data, let's see if any of the data hasn't moved in, say, the last minute. hmm. zero change, at the hundredths of a degree level, in a minute. AOAs don't do that. Lets discard those ones instead ..."

With the amount of redundancy in modern systems, posting a message every time you lose redundancy would overwhelm the crew. Its only merited, in my opinion, if it brings you to a point where you are a single failure away from trouble. In this case, they were not supposed to be that close to trouble.

To address the issue of a message stopping a test - that's why some aircraft have test-specific configurations and strappings, to ensure that stuff you need for test is available, but does not clutter up the normal displays.

MFS

With respect, and it may be just an error in understanding, your reference to the crew being "overwhelmed" is precisely the problem: trained crew don't get overwhelmed, it's in the T/C's. Seriously, if the capability exists to alert to a potentially dangerous condition, especially when the crew should be sensitive to it ( "Test" ), and it isn't forthcoming, that is a 100 percent FAIL in the machine/man interface, No?

There are at least two means to check 'reasonableness' of an AoA value:
a. the method apparently used by BEA to calculate AoA: from vertical speed, TAS and attitudes in pitch and roll;
b. the algorithm that presumably produces the "CHECK GW" message: from the GW calculated in the FMS, airspeed and accelerations.

regards,
HN39

P.S. Perhaps the 'monitoring system' should not be trusted to say which parameter is at fault, but at least it can indicate that there is an inconsistency between the parameters involved.

@ bearfoil

Perhaps overwhelmed is an emotive term, but the fact remains that the messaging and alerting system is designed with very definite constraints on what it can post and when, because overloading a crew with extraneous information is a hazard in and of itself.

Many "advisory" type messages - typically white, or status, or some other term is also used - are not posted AT ALL in flight. Yet they are an indication of reduced system redundancy, and maybe, just maybe, are symptoms of something greater, though they are not supposed to be. (This accident would be an example of this).

There are even phases of flight where caution messages - which ordinarily would be a very big deal indeed - are suppressed or masked in order to avoid crew distraction. I'm 100% sure there have been cases where aircraft have been lost due to masking of a message.

My point is, its accepted practice, for some good reasons, not to let every system on the aircraft post status messages where they are supposed to be having no effect at the cockpit level. To change that policy would require a very great shift in cockpit human factors thinking.

@HN39

It doesn't even need to be that complex to catch this case. An algorithm looking for a "stuck" - or in this case frozen - vane is rather simple. And I know at least one manufacturer has just such an algorithm on its products, which works quite nicely. I think the vanes are even from the same supplier. As I said a few posts ago, "unfortunate" that AB don't have the same logic. Perhaps they will soon, now ...

MFS

Amber color seems appropriate in the Airbus philosophy :
"The flight crew should be aware of the configuration or failure, but needs not take immediate action"
Such message could be assigned only a level 1 priority which is the lowest level of caution.

But whatever the color you like as long as the message is clearly transmitted to the crew.
It is not much about what the crew will do but more what he will not.

Overloaded ?
If such a message overloads me, maybe it’s time for me to quit the job.
I would probably be more prone to overload by simultaneous STALL and OVERSPEED warnings …

Maybe you’re not too familiar with the Airbus, but we have already a fair number of AMBER ECAM MSG that only require crew awareness nothing more.

MFS

Thanks for your patient reply. I do understand that the system has alert constraints. My point is that how expensive or complicated could it be that in and around the attitudes and flight aspect that flirt with Alpha Protection (to include both inadvertant and volitional), it would seem the computer could excuse the constraint program to ennable AoA alert, eg: AoA #1 Fail. This would (Could) be facilitated by a Pilot command that directed pertinent alerts relative to the manouver being tested? I still think that an AH would be nice, and so on, but one can dream. Crumbs, Crumbs, Sir! Viable? Wouldn't it generate an ACARS? How silly is it to inform the ground, but not the Pilot!!

bear

Two parts to that:

Having a different system configuration for a test certainly is possible, but usually would be for the duration of the flight. We do something similar to activate certain displays and parameters during production flight test. But it's not pilot selected. Anything that is selectable means having to deal with failure conditions for the selection, which adds complexity to the overall failure case analysis.

Having the system know to not mask certain messages as a function of flight manoeuvre is not trivial. Indeed, the suggested criteria implicit in your suggestion - use proximity to High Alpha protect mode thresholds to post alpha-related failures - wouldn't have worked at all in this case, because the failure is preventing the system realising it should be in alpha-protection mode, so it also would leave the message masked.

Typically phase of flight is used to control messaging and masking - air/ground is one criteria often used, and "during takeoff" is another, for examples. In this case I can't think of any simple criteria other than to post all the time or not at all, because alpha-protection is active in all phases of flight, and could be encountered under virtually any conditions. So once you've decided "this must be posted if alpha-protection may be activated" then you're pretty much posting it all the time.

All airliners have good and "not quite so good" features. All airlines have good and "not quite so good" SOP's.
If you read the CVR transcript you will not find one FMA call, not one ECAM caution read out loud when failures were introduced.
I believe that if "FLIGHT CONTROLS DIRECT LAW" and "USE MANUAL PITCH TRIM" had been spoken in that cockpit on that day they would almost certainly have survived.
That is the way Airbus expect their aircraft to be operated in a malfunction situation.

Those messages came up only as the emergency situation was already well developed. The aircraft had 50 degrees of bank, the stall warning was all over the place, possibly some additional ECAM MSG for the FACs, who would have seen and read those messages … ?

10 minutes earlier, as the aircraft was approaching VMO, a golden opportunity existed to positively advise the crew that the AoA probes were in disagreement …

TyroPicard, I don’t think it is necessary to kill the crew a second time as we all agree the flight was really not performed as it should have been, but could we grab that sad event to learn something on the manufacturer side as well in order to improve safety ?

The Airbus is a very complex machine when you want to look inside, and in the doubt, it should not hide its possible status. Nothing can justify that the protections may bring any additional level of difficulty for a crew.

CONF
I think you are an engineer? Therefore you see a technical problem and a technical solution.
I am a (retired) pilot who teaches A320 Type Conversions - I try to train pilots to cope with the kit that Airbus give them.
I am not killing the crew a second time, but trying to use this accident to reinforce the need for clear communication under adverse conditions. Just because it is a human factors/technical accident does not mean we cannot discuss the HF side...

Someone should have.... And USE MANUAL PITCH TRIM appears on the PFD so is easy to see and read...

No, not with 50 degrees of bank and many warnings already on. The pilots haven’t seen it, even the guy in the middle hasn’t seen it and as you give simulator you know well how the third guy is always suddenly so much 'smarter', you can see so much more by just seating on that third seat.

We can discuss HF of course and we HAVE to, but the BEA report is all about it already, but a lot evasive on the technical side : Where are the acceleration data ? They played a crucial role in the absence of forward auto trim when the captain was pushing on his sidestick, they played a crucial role too on the way the airplane was limited in the final maneuver.
Have you seen those data ?
Give me a reason why they’re not published ?

I’d like to see also the FO sidestick inputs … don’t tell me he was brave enough not to touch it …


To be honest, I’m getting tired of that constant attitude from the BEA to protect Airbus :

Page 16 of its report, the BEA dares to write:
Between 15 h 04 and 15 h 06, angle of attack sensors 1 and 2 stopped moving and remained blocked until the end of the flight at almost identical local angles of attack and consistent with the cruise angle of attack, without the crew noticing it.

It is obvious that this expression aims to release Airbus responsibilities where we should read :
without the crew being informed
That is intellectual dishonesty ! henrimarnetcornus.20minutes-blogs.fr