@maxbc that is correct. In discussion with an Airbus training captain, when the airspeed input to the ADC failed, and the Flight Director commanded pitch up because the altimeter reported around 500 feet below bugged altitude, the stabilator auto trim would kick in (recall in a transonic zone). Failure to recognise the scenario would mean letting the control stick go would not allow the airplane to naturally recover as the Airbus logic requires an actual movement forward of the control stick and probably reversing the effect of the auto trim.
Several airlines put their training captains without a brief into this high altitude airspeed mis compare scenario, and most were not able to recover.
Recall high altitude stall events were not replicable in SIMs, and therefore no training in them, before lessons were learned from AF447.
The main point is that on Airbus in normal or alternate law you would need to move the stick forward not just let go. Then your muscle memory is trained to worry about MMO over speed as your margin to MMO is smaller than your margin to lowest selectable speed indication (crew didn’t have any speed indication). In the Boeing the lower margin would be stick shaker speed, no stick shaker concept in the Airbus.
Just finished the book. Ouch. Yeah, you can make excuses, but the bottom line is that the PF didn’t recognise a stall and appears to have had no idea what one is nor how to recover from it. The author tries hard to make excuses for him but his heart clearly isn’t in it, and in his final summary he does actually use the word “incompetence”. But then, he had received absolutely no stall training since his initial A320 checkout. So you CAN somewhat “blame the system”.
At the time my thought was that all airline pilots should be made to sit in a for-real C152 or similar for an hour a year and do basic upset training. I think it a lot more now!
After that and the Concorde book, not to mention the recent total CRM breakdown incidents, it would be a brave person who would set foot on AF.
johnh wrote:
At the time my thought was that all airline pilots should be made to sit in a for-real C152 or similar for an hour a year and do basic upset training. I think it a lot more now!
This is now needed before any TR in EASA world (called advanced upset recovery training or “UPRTa”). I had this course with a great canadair/B738 captain, and he was pissed of because of this training (except the financial return), because stalling an liner, and a C152 has nothing common, doesn’t feel the same, and doesn’t recover the same.
Also in any TR, you also have an UPRT sim session with some very unusual position, and sometimes replays of such scenarii.
For liners, there are actually a point where HS has any hardly effect near the super stall, and moving the wheel hardly does something, and you are taught to put the ruffed full on one side, to pu the plane on the side, where it will take a nose down attitude. In the B738 sim, it took 15000ft (from FL380) to recover for such attitude.
In the B738 sim, it took 15000ft (from FL380) to recover for such attitude
You also need to come back to dense air to be able to recover (same if engine flameout you need dense air to restart it)
UPRT may adress the lack of stall and physics understanding, this may not help recovering an airliner when it drop from FL400 but likely will teach one to recognise what happens (even if they don’t recover, at least they understood what was going on with the aircraft…this is sad thing about AF447 CVR audio recordings)
stalling an liner, and a C152 has nothing common,
I’m sure that’s true (doubt I’ll ever find out). Still, the fundamentals ARE the same – excessive AOA, which means reducing AOA to recover, which means down elevator. Maybe lots of it (not in a C152 – or any spam can – though, where just neutralising it works fine). (The Extra supposedly requires full forward stick to recover a spin, though in my brief experience it doesn’t).
As @Ibra says, at least if you know you’re stalled, you stand SOME chance, Whereas PF Binon never even figured that out, so stood no chance to recover.
Is a swept-wing jet stable in roll, in any stall (including “deep stall” – many dispute AF447 was in such) regime?
If not, then why is a recovery not possible by letting it roll to one side, at which point the VS alone should make the nose point down, you gain speed very fast, and recover.
Maybe there is a reason why this is not feasible, and for sure it would be an extremely aggressive technique, but I can tell you it works in the TB20 because with the full TKS that drops the left wing (because the TKS panel is shorter there) quite fast 
Peter wrote:
If not, then why is a recovery not possible by letting it roll to one side, at which point the VS alone should make the nose point down, you gain speed very fast, and recover.
AFAIU that’s exactly what is taught for recovery from nose-high abnormal attitudes in airliners.
“Deep stall” is (or was originally at least) unique to T-tail jets (the BAC 1-11 in particular), where the disturbed airflow over the wing stops the elevators from working at all. Hence it doesn’t apply to a normal HS arrangement.
If not, then why is a recovery not possible by letting it roll to one side
I think that’s what greg_mp said (interpreting the typo). I was taught that for the (highly unlikely) event you find yourself way nose-up, such that you’d run out of energy before you could push the nose down in the normal way. It certainly works in a small plane.
I wonder whether it would even have worked for the fatal BAC 1-11 deep stall – easy to say from the comfort of an armchair of course.
greg_mp wrote:
and he was pissed of because of this training (except the financial return), because stalling an liner, and a C152 has nothing common, doesn’t feel the same, and doesn’t recover the same.
A reputable aerobatic flightschool close by gave away 3 upset recovery training scholarships and I was fortunate to be picked. I subsequently “upgraded” to a full EASA conforming A-UPRT two day course. The instructor was a german fighter pilot with extensive F18 experience (NATO exchanges) etc.. he was very good. The training was great, but I agree I don’t see its effectiveness for air transport/airliner scenarios. Additionally to advanced MCC it feels more like milking students more and more…
@Snoopy not sure you can conduct an A-UPRT course in a tandem seat aircraft, at least in the UK and EASA.
The old UPRT courses were relatively unstructured and designed to build resilience and manage startle and surprise. One airline on the competency MPL model required cadets to master inverted medium terms, clearly not that relevant to commercial airliners :)
The A-UPRT is more structured introducing more elements of CRM and key case studies. The five hours of ground school is devoted mainly to understanding swept wing, commercial air transport aerodynamics and stall characteristics both low and high level. A poll of students shows interesting gaps from EASA Theory Knowledge on the effect of compressibility on critical alpha, or why auto trim is necessary at transonic speeds.
I would suggest the A-UPRT, at least the courses I am familiar with, is an improvement which sensitises the students to critical aspects of learning when they go for their MCC APS and type rating. It also builds some resilience in that they do observe real upsets and have to apply correct recovery techniques, albeit in a straight wing propeller aircraft.
