Question

The engine of an aeroplane rotates in clockwise direction when seen from the tail end and the aeroplane takes a turn to the left. The effect of the gyroscopic couple on the aeroplane will be

(a) to raise the nose and dip the tail

(b) to dip the nose and raise the tail

(c) to raise the nose and tail

(d) to dip the nose and tail

This question was posed to me in final exam.

This interesting question is from Precessional Angular Motion topic in chapter Gyroscopic Couple and Precessional Motion of Machine Dynamics

Answer 1

The correct option is (a) to raise the nose and dip the tail

To explain I would say: When the engine or propeller rotates in anticlockwise direction when viewed from the rear or tail end and the aeroplane takes a left turn, then the effect of reactive gyroscopic couple will be to dip the nose and raise the tail of the aeroplane. When the aeroplane takes a right turn, the effect of reactive gyroscopic couple will be to raise the nose and dip the tail of the aeroplane.