Vielen Dank, Franzl, for posting "Pilot guide to aeroplane upset recovery". It is very useful reading, learning lessons from it might save someone's flying rear yet but I do not think it is applicable to AF447 case. It mentions that definition of aeroplane upset includes
unintentional.
In other words, the aircraft is not doing what it was commanded to and is approaching unsafe parameters.
Beyond any doubt, pulling the aeroplane into stall was not intentional, however aeroplane did just what she was commanded to. Looks as if 447's crew simply forgot how to fly an aeroplane. So crashed.
Originally Posted by CONF iture
Attitude is the objective, but 36 ways to reach that goal, how smooth or not you can or want to be is the director of your inputs.
Clandestino, if you start feeling Gs do you still pull harder or you just relax … ?
My sincerest apologies, sir. I was under distinct impression I was debating with professional pilot, rated on FBW Airbus. I mistakenly believed that we share some common background so there would be no need for me to go into details that are ingrained in basics of airline pilots training, such as technique of instrument flying. I now see that by omitting the details I believed would be familiar to you, my answers came across as quite harsh, snobbish and disrespectful. It was not my intention. From now on I'll try to dumb it down to level of high school physics.
Most important and most often checked information in "blind flying" is attitude. If one cannot read it properly or cannot maintain it properly, the rest of instrument scan is in vain.
When pilot is handflying by sole reference to instruments, it is important to keep movement smooth and precise to avoid unnecessary maneuvering that might upset pilot's sense of balance and induce illusions of turning or banking. Pilots who, when without outside visual reference, start flying by their senses instead by their instruments, get far more often killed than not. That is known fact that is with us since there were first instrument flights and no amount of sophistication and automation is able to isolate us from it, as was correctly, in more general terms, predicted by Antoine de Saint-Exupery.
So, as instrument rated pilot, I don't fly by feeling Gs, I fly by reference to my instruments.
Originally Posted by CONF iture
Except that 5 degrees of AoA on AF447 and stall warning is already warning, stall itself is just about.
what about a more common sense 2.5 deg pitch ?
Non, monsieur. You are mistaking the angle of attack and pitch. Pitch is angular difference between aeroplane's longitudinal axis and horizon. Angle of attack. in the most layman's terms, is angular difference between where nose of the aeroplane is pointing and where aeroplane is travelling to through air (velocity vector), measured in aeroplane's vertical plane. So AF447 was traveling at 2.5° cruise AoA and recieved first two stall warning as it was pitching up in turbulence, they were quite short and only transient and stopped promptly. It is also important to understand that stall warning sounds before actual stall takes place. It is certification requirement, purpose of which is for pilots to have enough time to make corrective actions before actual stall takes place.
Old unreliable airspeed procedure directed pilots to fly 2.5° attitude and power from table. New procedure, valid at time of AF447 final dive, called for setting 5° pitch with climb power for a couple of seconds, while PNF takes out the table of pitch-against-power from QRH and then power and attitude are set accordingly. 2.5° pitch is fine if you know your cruise power by heart. With climb power it would likely result in overspeed.
Originally Posted by HazelNuts39
I agree with PJ2 and others that going to 5 degrees pitch is not what one would expect a seasoned pilot to do, and is not the right thing to do in the circumstances. Depending on how quickly the airplane is rotated to 5 degrees pitch, the AoA would probably temporarily exceed the stall warning threshold of about 4 degrees, and in any case the 'stabilized' AoA in still air would move closer to the stall than with 2.5 degrees pitch. On the other hand I believe, based on 'gut feeling' rather than a numerical analysis, that if CLB power had been set and attitude had increased to but not exceeded 5 degrees pitch, that the airplane would not have stalled.
I would expect them to do exactly that as UAS procedure valid at the time of crash demands it. Page 59 of accident report refers. Your gut feeling is correct, I have explained why a few pages ago.
Originally Posted by Lyman
Why then, no "compensation" for the elevator position? The stick is held back sufficiently to command autotrim, but none shows.
Demanded load factor was met by elevators alone. Reason? High dynamic pressure at start of the climb.
Originally Posted by ruderruderrat
The FBW computers are programmed to maintain attitude, so more nose up from the elevator is required.
They maintain attitude when stick is pitch neutral. In normal and altn law they are programmed to meet G demand set by sidestick.
Originally Posted by Lyman
If PILOT/PLANE communication is critical, wouldn't the a/c have annunciated to the crew that pilot input was being g managed?
One only needs to look int Flight Crew Operation Manual (FCOM) to see that info. Pilot input is always G managed, except in direct law.
Originally Posted by Lyman
There can be (have been) circumstances where 'g' PROT might have wanted to be sent packing?
Only if one is purposefully set on breaking up the aeroplane in midair through overstress. Absolutely not applicable to AF447. Aeroplane never came close to G limits.
Originally Posted by Lyman
The chronic application of PITCH UP by this pilot is made easier to understand (by me), when one imagines the environment, the lack of "Response"
People who don't understand that if they pull and nose doesn't come up (EDIT: sorry, I wrote that terribly wrong the first time), there are 99.99% chances they are stalled, are usually not allowed to go solo in gliders, microlights or light aeroplanes, let alone climb the ladder to professional aviation. 0.01% caters for airframe failures, control circuit failures, etc.
Originally Posted by Ian W
If (as suggested earlier) the THS had remained at NEUTRAL
There is absolutely no NEUTRAL position as such on any THS fitted to any aeroplane, anywhere. There is neutral position for speed, altitude, weight, balance and configuration. It can be anywhere within stabilizer operating range.
Originally Posted by Ian W
Was there any training or flight envelope information available to A330 crews that told of the possibility of deep stall?
No. It would be a lie. Airbus 330 is not prone to deep stall/ superstall/ locked-in condition.