Old 11th Feb 2015, 10:21
  #3186 (permalink)  
RetiredF4
 
Join Date: Jun 2009
Location: Germany
Age: 66
Posts: 782
Although this thread is about the lost air asia aircraft and we still do not know what happened in detail, one discussion focused on stalls and the way to recover from those.

Vilters
I am a pilot.
Flew light to medium, even have a BFM (Basic Fighter Man) hr in an F-16B, and yes we pulled the whole 9G's a couple of times.

No, all those "Thousands of hrs" airline pilots do not need a single extra hr in a simm. NOT a single hr.

They need "REAL" seat time in a Cessna 152, a Pitts, or a Cap10.

They "need" some "REAL" and "DIE HARD" stalls to cope with, not in any simm at all, but in real life.

Where their bottoms come loose from the seat.
Where the break drops the nose deep and the wings fall ways from you.

I'v had "real" pilots turn white as paper.

I'v had guys shouting and screaming; sweating and strugling.

All they ever did was; "Stay away, stay away, recover before the stall."

Well, I fear the results speak for themselves.

And then do a full deep stall in a twin.
And teach them to cartwheel out of the stall. Full rudder and Full power on one, chop the power on the second, and cartwheel overhead out of the stall.

Then you will have pilots that start to understand stalls.

You might see some pilots turned WHITE, but you"ll have better pilots.

You can put them in a sim for weeks, nothing will ever change.
I do agree with a lot what you are saying.
Doing stall approaches and stalls and revovery from those in the sim might be usefull as an procedural thing, but it will never be able to replicate the physical behaviour of the aircraft and its influence on the human brain. To understand stalls and their influence on the human body and brain you have to have first hand live expierience of of such a situation and the necessary recovery steps, as the recovery will be even more uncomfortable than the stall itself.

Recognizing the stall:
The stall entry might be smooth and gradual with modern FBW aircraft, preceeded with some airspeed decrease and increase in pitch, maybe some vibration, and then the ship does not follow the commands like it should, descent rate will increase while some wing drop might occcur. That is unusual, but it is not asociated with alarming loadfactor changes or violent maneuvering. Therefore stall warnings should always be treated as real unless proven otherwise.

Breaking the stall:
Already the first step for the recovery, to reduce the AOA by bringing the nose close to the flightpath is a maneuver never performed before, the change of the loadfactor from 1g to 0g and the immidiate never before expierienced sensation of weightlessnesss of the body will make one sweat. The arm on the SS will no longer be supported by the armrest, or the arm on the steering horn will not rest on the upper calf, Legs will not stay on the floor by themselves, papers and stuff flying around, a completely differnt situation from the one just seconds before. Combine that with the need to act against long trained reflexes, to disregard the altitude loss, to disregard the bank angle, to drift off from the intended course, to pull power levers back instead of advancing them and to deliver the passengers a load of discomfort and even the risk of severe injuries. The next task is to maintain this input long enough, which will most probably lead to a never expierienced nose down pitch position, which in connection with the 0g loadfactor will give the sensation of surreal acceleration.

Recovery to normal flight attitude:
When the stall is broken and flying airspeed is regained the recovery has to be initiated immidiately to prevent an overspeed, but with enough care in order not to overstress the airframe. Power has to be adjusted to manage available energy. Secondary stalls are a common occurance in stall encounters, therefore concentration should focus on regaining a level pitch and bank attitude and stabilize the normal aircraft parameters. Regaining lost altitude, regaining navigation and informing ATC are of secondary importance to attitude and speed.

CRM under stall encounters
Both crew members have to be trained to the same standard, that the PNF understands and accepts the maneuvers flown by the PF and asists with the appropriate informations, speed being the most important of all, while a myriad of warnings are blaring and the ECAM puts out messages faster than one can read. Out of control response was a briefing item for every flight with my weapon system operator, so he would know what my plan of action was.

Look at the posted BEA video, how fast and gradual everything happened, bad that it does not incorporate the nz graph. The AF447 crew failed in all of the above parts, they had no chance.

Wishlist for training
It is not a situation one wishes to encounter unprepared. Most important would be a thorough introductionary course with lessons, sim training and some real stall demonstrations / practice and recoveries. A refresher course should be mandotary when changing type or after elapse of a predetermined timeframe.


I do not agree in the application of lateral control inputs by flight controls or asymetric thrust. In a stalled situation those inputs are pro spin inputs like Machinbird correctly says, and no skygod will get an airliner out of a spin. Those tails on transport aircraft have mighty control surfaces, correct usage (trim and elevators) should give enough authority to reduce the AOA.

Thanks to the mods in allowing these discussions, although we do not know yet if they are relevant to this thread.

Last edited by RetiredF4; 11th Feb 2015 at 13:19.
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