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Old 11th Jun 2009, 00:35
  #1111 (permalink)  
ClippedCub
 
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Tech log's not the place. Will make it compact.

Transport aircraft are demonstrated to an FAA FAR requirement that exceeds Vne at 1g. Flutter is a possibility, but simple structural failure is more likely. The WTC aircraft were flown well beyond Vne without flutter for example.

Mach buffet is not to be confused with flutter. It is merely flow separation on the wing due to stronger than normal shock waves, and is a function of lift and Mach number. It's operational limit is defined by the level of uncomfortable vibrations felt in the cabin, and is not destructive.

The tail is designed to a higher design Mach number than the wing, and is characteristic of thinner airfoil sections, and/or increased sweep so you have unhindered control to back out of buffet. Flutter wise, the tail is stiffer than the wing due to structural aspect ratio/stiffness, and the wing will typically flutter first.




Failure due to flutter could be considered less likely than encountering gusts at beyond Vne speeds. Even then, the wing would have load alleviating fuel in the tanks, so it could withstand more than you might expect. It's entirely possible that the weak point could be the horizontal tail. If it departed in a downward direction, it could peel that section of empennage with it, leaving the vert momentarally attached at the front.

Apologies if this is too long. Bin if desired.

Last edited by ClippedCub; 11th Jun 2009 at 12:31.
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