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Old 3rd Sep 2014, 09:15
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CaptainProp
 
Join Date: Aug 2002
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Vilas, the problem is that "qualified" and experienced airbus pilots are flying around thinking the aircraft is immune to stalls.

With regards to selecting Flap 1, and as already mentioned by previous posters, the FCOM only recommends selecting Flap 1 When out of stall.

From the FCTM:

STALL RECOVERY - The immediate key action is to reduce AOA: The reduction of AOA will enable the wing to regain lift. This must be achieved by applying a nose down pitch order on the sidestick. This pilot action ensures an immediate aircraft response and reduction of the AOA. In case of lack of pitch down authority, it may be necessary to reduce thrust.

Simultaneously, the flight crew must ensure that the wings are level in order to reduce the lift necessary for the flight, and as a consequence, the required AOA. As a general rule, minimizing the loss of altitude is secondary to the reduction of the AOA as the first priority is to regain lift. As AOA reduces below the AOAstall, lift and drag will return to their normal values.

- The secondary action is to increase energy:

When stall indications have stopped, the flight crew should increase thrust smoothly as needed and must ensure that the speed brakes are retracted. Immediate maximum thrust application upon stall recognition is not appropriate. Due to the engine spool up time, the aircraft speed increase that results from thrust increase, is slow and does not enable to reduce the AOA instantaneously. Furthermore, for under wing mounted engines, the thrust increase generates a pitch up that may prevent the required reduction of AOA. When stall indications have stopped, and when the aircraft has recovered sufficient energy, the flight crew can smoothly recover the initial flight path.

Here some comments on the subject from two very experienced guys, an interview with a Terry Lutz, airbus experimental test pilot and Boeing deputy chief 777 test pilot Van Chaney, last year in Flight Global:

.....pilots have been incorrectly trained for years to concentrate on maintaining height. "You must be willing to trade altitude,"
Pilots need to identify the risk of stall at high altitude, he says, recognise the onset of buffet and memorise appropriate pitch and power settings. But they must also know how to break the stall, with nose-down input, and - crucially - be patient. "Airspeed build slowly. Altitude must be traded for airspeed," he says, adding that engine thrust might be ineffective.
Chaney says thrust demands particular attention, particularly during low-altitude recovery. "I caution our pilots to be very careful with thrust application," he says. Restoring normal pitch and roll, he stresses, are "of secondary importance", particularly in a turning stall, for which he advises a two-step recovery - lowering the nose before smoothly rolling back to the horizon as airspeed increases. Simultaneous dual-axis recover is "not desired", he says, because it risks higher tail loads and reduces the effectiveness of control surfaces, delaying recovery.
"You fly into the stall, and fly out of the stall," he says, cautioning that rapid reduction of the angle of attack risks dropping the horizontal stabiliser into the wing vortices.
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