Originally Posted by gums #1698
With unreliable airspeed (think impact pressure, dynamic pressure, CAS/IAS), I look at some of the alternate laws and still see clues that the confusers are trimming the THS. So without airspeed, the jet is still trimming to maintain one gee. It does not care about the pilot aft stick input other than to keep the stick deflection about the same angle regardless of speed. How does it do this? It uses the accelerometers that are the major players for the basic control concept of a gee command versus an AoA command system. You don't need airspeed for the accelerometers to work. Same for body rates. Saw this on one of our accidents when a pelican wiped out pitot tubes, hemispherical air data gizmo and AoA vanes.
So a constant, even a small aft stick, that is commanding maybe 1.1 gee could result in the confusers increasing the THS angle to maintain the same stick angle for the commanded gee. No air data required. This might explain the THS increasing angle.
Concur.
The C* Law in the A320/A330/A340 is gee driven. Alternate Law 1/2 are variations/protections bolted onto the C* Law. In Direct Law, the stick is a B737 control column and its WYSIWIG including trim.
Lonewolf_50;
f you don't train for a stall recovery on instruments (for reasons previously explained, to include sims that can't replicate it), what does a pilot finding himself in a stall have in his training background and experience to draw on in order to redirect his scan.
I think this is one thing that is going to come out of this accident - proper stall recognition and training and not mere entry-and-recovery (where minimal loss of altitude has been not only stressed but is an actual IFR-ride failure if more than nnn feet are lost in the recovery!! - clearly designed for low-altitude stalls, (and even that didn't work for THY).
To do this, both simulators and curriculae have to change and that is a very tall order given the comments on sim performance beyond loss of control regimes.
Given the past ten years' data on stall accidents however, the industry is showing that it needs to do something. Along the way, the discussion about automation and the man-machine interface will take place in earnest just like we wanted it to when we checked out on the A320 in 1992.