Agree entirely with vilas.
Imho the use of the term 'deep stall' is a dishonest distraction in this case.
The term 'deep stall' was introduced, iirc, for aircraft whose configuration ( usually T tail) allowed them to enter configurations where the tail plane was rendered ineffective because it was washed by the wing turbulence.
In the AF 447 case, the airplane was stalled by the PF and then held in the stall configuration. As has been pointed out by others, just letting go of the controls might have save the day.
So no sign of a 'deep stall', except perhaps in the mind of the PF.
The legal case really should focus on AF CRM, the PM who was senior recognized that the PF was mishandling the aircraft, yet failed to intervene. That points to a serious weakness, but it still was not a 'deep stall'.

“… technique analysis has been done to death. The point now is the use of the law following an accident and the implications …” beardy #27
“This type of accident will almost certainly never happen again .. What we see now are legal issues about who has to pay money to who and how much...” ATC Watcher #38

A concern for the industry is if the findings set unwarranted precedents.

Whereas the 737 Max identified deficiencies in the design requirements and certification process - must be chnged, these aspects were not an issue with AF447.

AF447 involved assumptions about conditions outside of the requirements; the fault had been identified and was being addressed. The crew behaved as reasonably could be expected in conditions which were beyond regulatory assumtions, and thus any recovery would be classified as fortuitous, even if previous crews had succeeded. There are no reports of investigations into the previous successes, nor how the encounters differed environmentally; thus there is little or no justification to assume that subsequent crews would manage similarly.

Whist the legal process could have adverse outcomes, we should leave those battles to Airbus and AF until there is fact. The important aspect is to review what can be - should be learnt about aspects beyond the accident and thus what everyone should consider to improve safety.
Design, certification, regulatory, training, operation, and individually.

70 Mustang

what do you mean, deep? A stall is a stall, the recovery is the same. Show me in the Airbus FCOM where the recovery procedure for a Deep Stall is vs a Stall.

Some humor is being lost in the translation here :rolleyes:

But we seem to be only discussing the depth of stalls now which is not the subject of this thread . The AF447 court case is .

Most of us are trained to recover a stall as soon as it is recognised, at the incipient stage. Or, if instructed to; at the first wing drop. We do so primarily by pitching down to unstall the wing.

As I understand it; AF447 was held in a stall for an extended period, with full back-stick, resulting in low forward IAS, and high downward V/S, during which time, the Stab trim wound NU as far as the FBW allowed.

Call that what you want, but it wasn't really a 'normal' stall situation that we are all used to recovering from.

For the court case: How was that pilot trained? Was he trained? What part of his training told him to hold full back-stick during a stall?

That is the essence of the part of the current trial which is against AF : training . Reading the first (BEA) report one can see that they did not recognize the stall. Not only the PF but the 2 others as well, including the Captain at the beginning , only towards the end, he , and he alone , realized it but it was(far) too late.
One chapter in one of the reports, I forgot which one , goes in detail into the AF training syllabus, as far as I remember hands on training was concentrating on approach to stall, not on stall recovery. Those were the requirements of that time, although most airlines and AF in particular have changed that drastically since then. In addition against AF are their decision not to install /buy the BUSS, the late change of the Pitot sensors and some other small differences AF had compared to other airlines that were more pro-active in that respect. , That is what the Judges , lawyers and their experts are debating now.

I think the court should also look at what kind of 'rest' the captain had before this flight and what AF's instructions on the subject may have been. There is also the question of how the captain managed the flight. Would you, as the commander, decide to take your rest period when flying through the ITCZ? I know I would have wanted to be in my seat during that time and would have managed the crew rest accordingly.

This it’ s difficult to understand for me too , first you decide not to avoid an area of cb topping FL530 and , instead to sit there and make tactical deviation with the two other pilot , you decide to go for rest probably for the most difficult or critical part of the flight .

Closing stable door when the Cheval has bolted and all that, but no, very few of us would have taken that action. Whatever - he and his (alleged) mistress died in the ensuing. Only his 'estate' remains liable in law for that decision, unless AF 'rules' at the time rigidly prescribed when rest MUST be taken by the Captain, in which case, lawyers................alert!

They never realised they were in a stall, and the right-seater flying never acknowledged the PNF's quiet call out of Alternate mode, so he might well have believed he couldn't stall, being in normal mode. Of course all this was hashed out at the time, and it probably makes little sense to go over it again here, but I think questions about their training are indeed relevant to the judicial matters.

Bergerie1 : This has been debated already during one of the trials, , and if I remember correctly the SNPL (AF union) had obtained earlier an injunction that actions during off-duty periods are private and should not be included in the BEA report . The gutter media reported wild stories but very few people if any know exactly what really happened during the rest period as all the direct witnesses perished in the accident , What remains as facts are only a 1h helicopter tour , one email to a friend that he slept badly prior the flight , and some wild rumours. .

vaneyck

Hence the comment I made (and criticized for) in one of the other AF447 threads - perhaps it's not such a good idea to teach pilots that they can't stall a particular aircraft.

ATC Watcher

The court is not going to decide what the crew did was right or wrong even when to take rest. So many accidents SOPs are violated, mistakes are made. The only issue is did the manufacturer know unreliable speed can happen if so did they have an adequate procedure to deal with it. If yes, Airbus is off the hook. Did AF impart that training to this crew? If yes the case is closed.

Vilas.
Fully agree with you . That was my point too and I concur with your logical conclusion.

Many of the complexities of the crew's decision making, and lack thereof, got addressed in the report from the California Training Institute: https://www.hptinstitute.com/wp-cont...rance-4472.pdf

tdracer

Pilots need to know it doesn't stall in normal law because that affects GPWS terrain procedure. It only stalls once out of normal law. The pilots knew it they were taught stall recovery which can only be alternate law. Pilots were engulfed by fear because they didn't know what had happened and may be hyperventilating devoid of rational thought. Otherwise the Stall warning was blaring in the cockpit only a deaf couldn't hear that.

The 'Stall warning' was not 'blaring in the cockpit'. They had the angle of attack well beyond what Airbus had considered was likely and therefore beyond the angle where a stall warning was given. Therefore it was silent. At one stage they briefly lowered the angle of attack to a point where the stall warning was given. Their immediate response was to "undo what they had done that gave them the stall warning" and raised the nose again, silencing the stall warner. That does not sound like pilots who have been trained to understand the concept of a stall, let alone how to recover from one.

I will go back to the problem that I have mentioned of basic flying schools not even demonstrating fully developed stalls, let alone teaching their students to handle them correctly. The problem starts there...

But they end with Airbus 'designing out' stall warnings being given at extremely high angles of attack (stall warnings should be given whenever the aeroplane is stalled, without limits) and Air France having to answer questions about the stall recognition and recovery training.

Appreciate that but the stall is the essence of this case!

When the stall warning sounded it kept sounding till the crew took the AoA beyond the warning design. The AoA probes are like aerofoils need certain forward speed to measure the AoA. When the aircraft speed dropped below 60kts it was beyond design and was taken as unreliable and treated as non computed data and rejected. Then the warning stopped. But during this time the only action the crew had taken was opposite of what was required. So they were already confused. AoA probes are manufactured by another agency. Does anyone has any idea about say Boeing 737/777/787 whether stall warning will sound at at all forward speeds?

I have friends who joined Air France in 2015 and they told me flying raw data in daily line operations is a very common practice. They follow Airbus recommendations on that matter. I’m curious to know if that was the case before 2009?

A challenge for the industry is an increasingly litigious society, where people seek retribution with little consideration of the much higher standard of safety. This could restrain learning from events required to improve, or at least to maintain existing standards.
An emerging risk of inaction could reduce the perceived level of safety, continuing a vicious circle of more procedures, rules and litigation.

The baseline for the legal action was an accident resulting from simultaneous multiple sensor malfunctions where the acceptable probability of occurrence was beyond the certification requirements. It might be argued that the in-flight risk pending modifications identified from previous malfunctions could have been better judged; which would rely on on human (crew) understanding in real time.

The regulator has responsibilities for both design requirements and airworthiness issues, thus with increasing complexity in systems and operations the regulator should also be involved in the legal process - but to what point. Ever increasing systems integrity to counter extremely rare, and often unforeseeable circumstances which involve indeterminate human response - another vicious circle in the quest for perfect safety.

It's perhaps unfair to label as vengeful those who take legal action against parties they believe responsible for killing their family members. Retribution in the eyes of some may be just, if inadequate, compensation in the eyes of others. But the issue isn't about a point of perspective. I fully understand that learning from errors requires transparency which may be at odds with the adversarial nature of litigation. That tension isn't new and will never be resolved. But there is also a corner where the failures of supposedly highly-trained and trusted professionals reach the level of negligence, even criminal negligence. And to justify allowing culpable individuals to escape responsibility on the alter of fixing safety flaws in the system seems unjust.

So, to follow you, in fact, it should not be Air France or Airbus going to court but the certification authorities because they did not define strong certification requirements..

voyageur, agreed; it would be unfair to ‘label’ people, but that was not the intention. The point was to highlight that the apparent change - seeking more compensation etc, could have greater effect on the industry than we appreciate.

With increasing safety the industry moves way from blame, more towards understanding and thence learning. If there is no corresponding adjustment of legal view then the widening gap may create greater opportunity for compensation. With different viewpoints, the public might be less appreciative of the concept of error and blame as is aviation; thus legal findings could tend towards public perception. Also, whilst operations are conducted in complex multitasking situations where there are many demands on thinking and understanding, the legal process with hindsight, might only consider each of the demands sequentially, without the context of a demanding situation.
The legal process might not fully understand the tasks the crews face during an event, or designers and operators inability to foresee every alternative human reaction in surprising situations; thus culpability might only be concluded with hindsight.

Bidule, we should not blame certification authorities for a judgement of risk which has been accepted world wide and shown to be be adequate for many systems - and in other industries.
A rule change at this level would probably generate more automation vice attempting to quantifying the variable human in a risk assessment.

The critical point in this safety event is that it happened at all - obviously. There was a component malfunction - three simultaneously, which by all available means had been shown to be adequate. Meeting the requirements at the time, requirements which via higher accountability were acceptable to government and thence the public.

If change is warranted, then consider the process; which apparently has been improved in the icing requirements in CS 25; greater emphasis on ice crystals.

Also, in addition to the mandated modified probe, the manufacture has improved ADC logic, switching, and crew interface, yet some views cite this as an admission of prior error. Operators have reviewed checklists and training, but these and modification are obvious fallacies if used to justify uneducated criticism, which could generate a reluctance to improve safety - ‘we meet the regulation’ - ok, no more.

The industry requires a learning culture to progress safety, a willingness to advance beyond the minimum standard; the question is if increasing litigious action will hinder developing a safety culture - not change rules.
The Certification Authorities should appear for the defence.

safetypee. You are absolutely correct that the legal process to assign blame and/or impose punishment or set compensation is backwards-looking. Juries (or judges) reach binary verdicts (guilty or not guilty) or assign shares of culpability and hence compensatory and/or punitive damages in a process that requires judgement in hindsight. It's also true that it may be easier to conclude negligence when a babysitter allows an infant to drown in a bathtub because he/she didn't notice the plug was in than when three supposedly skilled, highly-trained, and expensively compensated professional pilots fail to recognize a stall for several minutes in perfectly flyable aircraft thus causing the deaths of several hundred people. I was only pressing the point that culpability in the cockpit (or the training school, or even the regulatory agencies) shouldn't be set aside because it might make lesson-learning more difficult. best regards.

safetypee

It would be enlightening, and at the least quite interesting, to find out what KSAs you hold with regard to civil litigation involving air crashes or accidents (knowledge, skills, and abilities - a standard assessment metric in American higher education including legal education).

i say this not because I disagree with any particuar assertion you've articulated about legal processes in general or about ""the" legal process. Rather, as a result of having had a fairly broad set of professional interactions with accomplished litigators - some in the defense bar, others for plaintiffs - over several years now, it's unclear to me which interrogative is the more pertinent one: Other than abstruse pronouncements about how safety-related processes function, what basis in actual fact or experience do you assert supports your view about litigation in these cases? (Aren't your posts generally long on abstractions, tending toward theoretical?) Or..... let's say you're actually one of the above-referenced top-drawer American courtroom litigators of renown, posting behind an assumed identity.....So, what foundational changes are you advocating in the Montreal system which (as is widely known and recognized) is the bedrock of civil litigation for international civil aviation?

[Any perceived snark or sarcasm in this post is both apologized for in advance, and not intentional.]

Hi Willow, no legal expertise as in your sphere; at best a layman (see pm).
However, sufficient experience in aviation, flying, testing and certification, and incident investigation - supporting formal investigations - to participate an abstract discussion from the aviation viewpoint.

My simple view of the legal position is that AF & Airbus are appealing the investigation finding, and subsequent court rulings and appeals which allow a prosecution to proceed - post #2, et al.

How can a manufacturer be held responsible for an aircraft which met all requirements, yet suffered a failure at a level of probability not considered by certification.
How might any differences between world aviation standards and local legal findings to be judged.

Similarly, how can an operator be held responsible for a situation (triple ADC malfunction and consequential system alerts) for which specific training was not required, and that training which was required had been approved by the regulator.

An adverse outcome, Manufacturer and/or Operator being held accountable for a situation, which previously met requirements of certification and training, would have detrimental effect for aviation and safety in general.

safetypee

Having pilots who do not understand or recognise a stall, or who do not know what action to take to recover from a stall it rather startling. It is one of the fundamental aspects of flying a fixed-wing aeroplane.

grizzled

these are good points and as in any accident, ‘everything’ should be considered relevant, unless proven otherwise i.e. rule out factors one by one and not have to rule them in

The probable answer to that question "why did nobody, ( 3 of them) recognize the stall " is described in the the 1984 Charles Perrow book , " Normal accidents " describing among other things the 3 Miles Island nuclear accident.
There is a difference in Human factors between what is logical on paper, and how humans faced with unknowns and stress react. Training is supposed to help bridging that gap. Training for stall recovery in one thing, but recognizing a stall starting with wrong indications on displays is another.

And consider also the condition at the moment , was not a stall recovery in still air by day , they where by night , in the middle of ITCZ , cb all around maybe inside , so probably extreme shear and turbulence , lightning , add the startle effect , not an easy job even will full data working .

Noel, et al, we have to consider what assumptions are in the questions; our inability to understand crews’ behaviour at the time, without benefit of hindsight.

Pilots are trained for stall recognition and recovery; they are not trained for the combination of erroneous airspeed and stall - manual flight at high altitude with many systems alerts and distractions. Nor in turbulence which masks natural stall warning, or stall at night / IMC, or with revised control laws, or …, … or in the real aircraft in a rare, surprising, complex situation.

The article below is an overview of the investigation and HF issues relevant to the questions.
Also see page 6 which relates to legal aspects (this thread), particularly the French view:-
“This investigation does not seek to determine responsibilities—that is the role of the judicial investigation that takes place in parallel and independently of ours, as laid out in French law. Unfortunately, in the mind of the public, it is not always easy to understand the difference. Many people expected the BEA investigation to point out responsibilities and even culpabilities.”
https://skybrary.aero/bookshelf/books/3337.pdf
Accident Investigation page 6 - ; and Human Factors Issues page 9 -.

As I have pointed out before. At the time simulators portrayed the A330 stall as conventional. i.e In alternate law pulling back stick stalled the simulator first buffet & then nose drop. Also simulators flew in alternate law the same at 38000 ft as 12000 ft. This is not the case in reality. IMHO the aircraft did not respond the way they may have been trained.

For everyone who has an interest in the causes and contributory factors for this accident, the following article, written for Vanity Fair by William Langewiesche in 2014, is as good a summary as you will find. The interrelationships that came together that night (automation, training, human factors, culture, CRM, etc.) are all discussed – and explained well enough for a general audience to comprehend.

https://www.vanityfair.com/news/busi...ight-447-crash

There is much more to this accident than "the pitot tubes became blocked with ice", or "there was no adequate procedure at the time", or "lack of training in high altitude stall", or "awareness and implications of Alternate Law".

IcePack

But were they actually trained at all in a relevant scenario (whether sim was faithful or not) ? I understood from the report that they were definitely not trained in either stall or UAS at cruise alt, only at low level where handling and required responses are different. Were they ever trained in alternate law at cruise altitude, at all ? - the report mentions alt law training but also states it was at low level, in fact high altitude alternate law training is stated as a change made following the accident (which pretty much implies it wasn't done before). If they were never trained, the simulator fidelity, or lack of, is kind of irrelevant.

Quite right, hence my word may. One of my annoyances is that at the time our training aides did not represent the real aircraft. It will be interesting to see if this comes up in the court case. I also wonder in reality how many pilots have actually “hand” flown any FBW Airbus at high altitude. Certainly a skill you need when everything goes “pear shaped”.