Lonewolf_50
Ian, please don't hate me for what follows:
First note: if the two pilots were both aware of them being in condition UAS, what is the likelihood that they were skeptical of stall warning, knowing that airspeed is a component of stall AoA calculations? That might explain in part the apparent "ignore" of the stall warning.
But I think that you are correct.
The first reaction to everything falling apart is disbelief that it is happening. So being sceptical of the stall warning is a 'normal' reaction. Like many other things when flying you have to believe the instruments - and - in this case when that was tried the normal instruments in the scan were either obviously invalid or flagged as in error. So it can't be true.
Then the PF appears to have followed 'normal law' control procedures when the aircraft was in alternate - and he had accepted that. But under pressure one reverts to ingrained behaviors. So his 'learned' response was inappropriate for the aircraft state. The only way to prevent this happening is continual training in reversions to manual control and upsets at cruise level. How many line pilots here have that? How many can say that they have more than a few minutes
actual manual piloting in alternate law at cruise level?
So when everything goes pear shaped - the crew are dropped into a situation that they have NO consistent experience of even in straight and level flight - but here they are in an upset that possibly gave one chance at recovery.
Second note:
From the latest release, the aircraft went into a condition of unreliable airspeed. What leaped out at BEA was that (if I read this rightly) the crew didn't progress to the unreliable airspeed checklist/procedure as was standard practice at the time. (If I misunderstand that, my apologies).
The information released shows me a PNF who had to focus on flying problems rather abruptly. His requirement to assist (rather than take over from??) the PF, to include the switch to (F/O 3 on the ATT select?? takata's illustration informs this) indicates to me that he felt that the PF was having difficulty with his PFD. Given the number of things going wrong on displays, and the PF being unclear on what he was seeing (from PNF perspective) giving the PF a better inertial unit to run his would be a helpful copilot (role) assisting PF. (If this guess is off, apologies).
In the meantime, hand flying at altitude with UAS in Alt 2: is this trained for?
If not, the PF was playing catch up.
This raises another issue that I have not seem mentioned much here. A 'constituted crew' where the Captain and FOs have flown together for some time and know each other and how they work will almost ALWAYS be better in an emergency than a random selection by roster. It may suit the bean-counters to have freedom to vary crew composition but it fails to engender team spirit. More importantly, when you have flown with someone for sometime you can both react and work-together almost intuitively. Someone should really quantify this teamwork effect in monetary terms as the accountants do not understand anything else.
A human factors question arises that may be answered by AF SOPs or habits, or it may not have an answer.
With what appears to be the senior pilot between the two recognizing a pilot who was fighting the aircraft a bit, or chasing it, his initial "talk him back into the scan/situation" is what most of us would do as good copilots ( in terms of our role at the time.)
At what point should/would it have been "I have the controls" when the PF kept chasing the attitude and the PNF kept having to prompt him to go in a different direction? (Aside: Isn't that the question every Captain must have a clear answer to before takeoff, or an instinct for, in terms of his threshold of "that's enough, I have controls" when his copilot is flying?) If the PNF made a number of inputs on the SS but didn't take controls, I know a few CRM people who'd be aghast, as the preference is that one pilot is on controls, the other isn't. (We could probably spend all day debating the intricacies of what's behind that.) WIth a SS, his inputs won't be felt by the PF, so the "summing" function may have less than the desired effect, as opposed to conventional controls where the PF would have felt what PNF was doing. <== Is this a shortcoming of SS, or an advantage? I can see it both ways. (Anyone whose instructor "rode the controls" while you were learning probably sees the issue here).
This dual attempt at controlling the aircraft is probably again a symptom of not having a constituted crew who all know each other well, rather than an administrative 'pecking order' or 'authority gradient' in the cockpit.
The problem of sidesticks and the visibility of what a pilot is doing both for the PNF and perhaps for the pilot himself. is a subject of debate among cockpit designers and pilots. Personally, I would think that for single seat aircraft and for 'flying the computer' a sidestick is probably good. For instances where a dual crew have to fly an aircraft manually (even if through some computer assistance) then the larger central yoke or joystick rapidly shows others what the PF is doing without the need for verbal or instrument clues that may not be easily available due to noise or vibration.
There are a HUGE number of human factors issues that will need to be investigated
- Multiple Alarms on multiple failures causing cognitive overload
- (In)Consistency of alarms (the stall warning) poor alarms reinforcing disbelief in instruments
- Belief in alarms - the crews MUST know which alarms to ALWAYS believe and the system needs to ensure that there are NO false alarms
- Display of reliable data/information during failures - it is sometimes better to have NO data than BAD data
- Manual flying of a squirelly aircraft at cruise in bad weather in alternate law (is it possible at all without constant practice?) with limited instrument information. The crew did not have this training. (Does ANY crew?)
- CRM and crew performance in upsets with constituted crews compared to random selections of front crews.
I am sure that there are more but this crew had EVERY one of those issues and probably 30 seconds at the beginning of the incident to get everything right or it would be too late. It proved too difficult for this crew to manage.
Is everyone sure that the crew they are next flying with would do any better in similar circumstance?