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Old 11th Oct 2016, 20:57
  #1173 (permalink)  
Chris Scott
 
Join Date: Jan 2008
Location: Blighty (Nth. Downs)
Age: 77
Posts: 2,107
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Stall recovery using AoA

Quote:
"Stall recovery using AoA was very simple, as the stall AoA was independent of attitude or gee ( previously asserted)."

Thanks gums: knew I'd get a clear view of practical experience from you. So would it be fair to propose that, having stalled the a/c, one simply pushes to achieve an AoA of a few degrees below the stall, and then maintains that AoA as accurately as possible during the recovery from the dive? Once the a/c is climbing again, the pull-up can be eased to maintain a suitable pitch and the AoA will gradually reduce as the IAS or IMN rises to the desired climb speed. At that stage the stall recovery itself will have been completed.

I'm likely to get some stick from the likes of yourself, Owain and others, but at high altitude the stall (or low-speed buffet) AoA is much lower than low-down, due to compressibility effects, and therefore varies also with Mach. So I'm guessing that would have to be taken into account when choosing a recovery AoA?

Normally, the Airbus FACs (augmentation computers) or whatever would be able constantly to calculate and display the stall AoA, but in UAS that would not apply. So a ball-park, conservative figure of stall AoA would need to be displayed to enable the pilot to choose a safe target AoA for the recovery profile.

In either case, if terrain clearance was critical, the pilot might have to shoot for a higher AoA (i.e., a lower margin below the stall AoA displayed).

Does that make any sense?
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