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Old 20th Jul 2011, 19:10
  #2080 (permalink)  
Lonewolf_50
 
Join Date: Aug 2009
Location: Texas
Age: 64
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Bear: g limits are +2.5, so you can assume that 2.5g is the limit for a pull out maneuver.

HN39 posted a modest 1.5 g pull out estimate a few pages back, and offered a conservative altitude loss estimate. (I think he's optomistic ...)

2.5 g is a firm pull out, but you won't typically get a gray out. Consider that 60deg AOB in level flight is a 2 G maneuver, and you may see what the "feel" is in the aircraft under such an acceleration.

2.5 g is within the aircraft's structural limits. It is (per the info I have access to) the limit of flight control accel limits (caveat: if you put on that much G while the airspeed is too slow, you may experience an accelerated stall, which can lead to a violent departure ... but there is no evidence that this is what happened.

Your comment that aircraft won't let you do that appears unfounded. (There was a neat thread elsewhere about CFIT and Proximity to Ground Warnings, and 'save it' manuvers. IIRC we also discussed this in the Air Blue at Islamabad crash thread ...)

As I understand the way the flight control system works, the pilots could pull for, or try to demand demand, more than a 2.5 g, and only get 2. 5 g. If you postulate that the pull out is initiated at altitude (somewhere beween 15-20k I guess, to allow time for the aircraft to react and for acceleration to flying speed and a fudge factor) you'd likely have brown trousers, and a flying aircraft with some margin at the bottom of the pull out as you add power and start getting your aircraft back up to a more comfortable airspeed and altitude.

Or not, and the aircraft impacts the ocean in a different condition than it did.
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