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Old 24th Aug 2011, 10:21
  #3207 (permalink)  
RetiredF4
 
Join Date: Jun 2009
Location: Germany
Age: 71
Posts: 776
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Re iceman50

Hi Franzl,

It was "looked" at in ALT Law and to get anywhere near 15 degrees will take a lot of sustained effort. It also looks way wrong on the PFD.

Ice

But that is, what happened here with AF447. They got way over 5° and stalled.

2:10:08 = pitch 5°
2:10:15 = pitch 10°
2:10:30 = pitch 13°
2:11:00 = pitch 15°
2:11:08 = pitch max pitch about 17°

And releaving SS at that moment would not have changed anything to a positive outcome. Releasing at less pitch than 15° would only lengthen the timeframe till stall would occur if not dealt with the problem by SS ND.

So my question was (and still is), to what time/ pitch you reference your term "after the initial pitch up"?
Even the 5° pitch would not be good for endless time, as same as stated above would apply. No protection, therefore maintaining 5° pitch until speed is below stall speed and same time elevators and THS full NU. It would take considerable more time and would leave more time to counteract though.

Itīs important to understand aerodynamic and energy management also in an FBW protectet aircraft, when those protections and ATHR go southbound.

Last edited by RetiredF4; 24th Aug 2011 at 11:01.
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