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Old 6th May 2011, 03:45
  #773 (permalink)  
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Join Date: Jun 2009
Location: florida
Age: 77
Posts: 1,141
Back to impact

Salute!

Well, after discussing this with another member here, I shall make another post that deals with the impact.

The French prolly have it right about a low forward velocity, fairly level attitude impact. I offer some excerpts from the LM Code One magazine that discusses the deep stall we had in the Viper.

One thing to look at is the statement that the jet was descending about 300 feet per second!! So it is entirely possible for impact to have taken place within 2 minutes or so from entering a deep stall at cruise altitude. This also provides an explanation for serious, deadly forces on the pax.



then the graphic:



then the vertical velocity and description of the descent:



Let's make this clear..... I NEVER got into a deep stall!.. I did a tail slide once, but the pitch rate after starting back down was so high that the flight control computer and control surfaces could handle it.

After looking at some of the control laws for the "bus", I can see the same thing happening as with the Viper. Computers try to limit gee and AoA and speed, but the c.g. and aero characteristics of the plane allow the thing to "settle" into the deep stall. The "bus" didn't have the MPO ( manual pitch override) that gave us direct movement of the stabilators with zero "help" from the computers. Closest the "bus' has is manual elevator trim wheel.
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