Vmca
Minimum control speed in the air – the minimum airspeed at which the aircraft is directionally controllable in flight with one engine inoperative and takeoff power on the operative engine(s). Aircraft certification standards specify the most critical engine becoming inoperative and its propeller windmilling (propeller unfeathered), not more than a 5 degree bank towards the operative engine, takeoff power on the operative engine(s), landing gear up, flaps in the takeoff position, and center of gravity in the most unfavorable position. In the USA Vmca is defined at FAR Part 23.149 for normal category and commuter category airplanes; and Part 25.149 for transport