11 A stall occurs when the smooth airflow over the unmanned airplane`s wing is disrupted, and the lift degenerates rapidly. This is caused when the wing
A. exceeds the maximum speed.
Supersonic speed will put a normal airfoil into a dynamic stall, speed is not the cause of an stall. Besides, sUAS are limited to 87Kts (Mach 0.130486).
This is not the correct answer.