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Old 28th Aug 2010, 12:53
  #2044 (permalink)  
HazelNuts39
 
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rockets for deep-stall recovery

Originally Posted by JD-EE
(...)What I'm proposing is that they were at that last stage with too little height to finish the pull-up or even finish a ditch scenario.

(...)Another thing the data and discussions have raised in my head is the absurd image if a tail mounted rocket pointed straight down with the intent of getting a plane out of a flat "spin" or sink
Regarding your first remark, consider also that according to Tim Vasquez' analysis, freezing level was at 16350 ft, and cloud base 2370 ft, so at some point they would have had airspeed back and become visual, even though it was dark night but moon-lit.

Regarding the second idea, it may be of interest that the prototypes of at least one airplane (the Fokker F28) were equipped with four solid-fuel rocket engines mounted vertically in the tail to permit recovery if the airplane would encounter a super-stall condition during intentional stalls conducted to explore or demonstrate stall characteristics for certification. They were never used in earnest, and were removed after initial tests had shown satisfactory stall characteristics. The F28 has rear-mounted engines and a T-tail, so the risk of super-stall was naturally considered early during its development. An airplane of conventional lay-out like the A330 should be recoverable by normal use of the elevator up to angles of attack well beyond maximum lift, but maybe not at angles as extreme as some posters on this thread have suggested, at which the horizontal tail surface would be fully stalled too. To get to those large AoA, I believe you have to persist in pulling the stick fully back, ignoring stall warning and increasingly heavy buffet.

regards,
HN39

Last edited by HazelNuts39; 28th Aug 2010 at 14:06.
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