Example 1: An aero plane makes a half circle of 50 meters radius, towards left, when flying at 200 km/hr. The rotary engine and the propeller of the plane has a mass of 400 kg and a radius of gyration of 0.3 m. The engine rotates at 2400 r.p.m. clockwise when viewed from the rear. Find the gyroscopic couple on the aircraft and state its effect on it. What will be the effect when it is taking right turn.