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Old 5th June 2011 | 05:20
  #1392 (permalink)  
PickyPerkins
 
Joined: Jul 2002
Posts: 233
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From: 40N, 80W
Several people have noted the 61° AoA of the mainplane and the 45° angle of decent, and agreed that the mainplane was therefore fully stalled.

With a nose-up up-trim of 13° the HS had an AoA of about 48° and was therefore also fully stalled, also with an angle of decent of 45°.

Although the mainplane and HS both had airfoil geometries, they seem to me to have been acting more like two drag-parachutes lowering the aircraft towards the sea.

In fact this arrangement was the answer to the problem that Burt Rutan had to solve it getting his Spaceship 1 safely back from supersonic speeds in space to low sub-sonic speeds in the lower atmosphere.



Spaceship 1 was a variable geometry air/spacecraft in which the tail could be trimmed to a nose-up of about 45°, which was enough to guarantee that both the mainplane and the tail would be fully stalled and act as drag-parachutes, bringing the aircraft back to a low altitude at a safe speed, without any other pilot action.

Once at a safe altitude Spaceship 1 could be trimmed back to normal, and safely transitioned into a glide back to the ground.

Gums Post #771 5th May 2011, 23:45 contains a description of a deep stall in an F-16:

.... with no buffet, vibration, or noise. ……”

That sounds to me as quiet as a parachute drop.

I wonder if that is what it seemed like on AF447?

Maybe a Spaceship 1 pilot (or passenger) could tell us on this thread what a Spaceship 1 re-entry feels like?
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