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Old 26th Feb 2009, 11:57
  #361 (permalink)  
Dani
 
Join Date: Aug 2002
Location: Switzerland, Singapore
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well I'm not sure if I get deleted but I try it nonetheless...

Nick, a transponder signal is never accurate as to read out a real speed of an aircraft. If you had the chance to watch some modern TCAS/ACAS systems, you can easily see how inaccurate they are. Transponders are not there to determine the speed of an aircraft but it's position (with a relative wide error).

This is especially noteworthy in case of an aircraft that decelerates or even stops. If your exampel aircraft would stop, and you would measure the speed 10 seconds before crash landing, which speed would it be? Most probably the average of the last 10 seconds.

Only the readout of the flight data recorder will give us reliable evidence on how the aircraft crash landed.

FSLF, teh picture shows a landing gear, but not the evidence if it was extended...

Ah, and DC-ATE, my favorite enemy, is also here! FBW aircraft are not stallable. And stick pusher close to ground is very very deadly. An Airbus can be flown at the lowest allowed speed with full controls without risking a stall, while on conventional aircraft you always have to build in a safety margin. Remember Habsheim.

Dani
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