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Old 29th May 2011, 10:43
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Ask21
 
Join Date: Mar 2009
Location: Norway
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Severe stall recovery

OK- I'm not a professional pilot - but I did my first stall/spin recovery from 3000 feet at age 14 in an sailplane training and solo flying( a long time ago) - so thats my background.

One of the most interesting issues here is what options the captain had when he arrived in cocpit - assuming he recognized the stalled configuation. Assuming the AoA allready in the +40 degrees area and 10000 feet/min sink-rate.
13deg trim obviously led to the disaster - but at 40 deg AoA on wings - would not the horisontal stabilizeer/elevator allready be fully stalled incapable of producing a tail-lifting force at all. At some point of stall development pitch authority will be lost - isn't it so

With a pitch +15 degrees - level wings . and Center of Gravity in the aft region - and since theres no stall recovery parachute installed - What are the options?
Triming down the elevator is obvious - but it would increase the AoA of the horisontal stabilizor increasing the stall of that surface

Exteding landing gears would be one option - to produce a nose-lowering force.
I suggest also a mild reverse trust on engine might be one of very few options available.

After all - what you would like to have is a pitch up stall converted to a steep - steep dive 70-80 degrees- where the forces of gravitation actually will work for you - not against you. In a steep dive with the nose directly towards the ground the Airplane will be flyable again.

So the most realistic option would perhaps be to "drop a wing" - using rudder or aileron if aileron autority still exist - and then use rudder to convert a high bank angle to a steep vertical dive - thereby enabling oneself to fly again

Last edited by Ask21; 29th May 2011 at 11:51.
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