The crash of the American Airlines Airbus in New York in November of 2001, has revealed that what nearly every pilot of all experience levels believed about maneuvering speed, Va, is incorrect. It turns out that a pilot can break the airframe by moving the flight controls even when flying at an airspeed below Va. The significance of Va has usually been taught to pilots as a negative. “Do not make full or abrupt control inputs when flying faster than Va,” is the standard description of the meaning of maneuvering airspeed. The implication of this teaching is that full or abrupt control inputs at airspeeds below Va can’t break the airframe.
The truth of this belief is hammered home with explanations of how the wing will reach the stalling angle of attack just as the G loading on the airplane reaches the design limit. Thus the wing stalls and unloads itself before exceeding the structural limit. This is true if the sudden change in angle of attack is caused by a wind gust-turbulence-that doesn’t exceed the certification standard.
