An aeroplane makes a complete half circle of 50 metres radius, towards left, when flying at 200 km per 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.
An aeroplane makes a complete half circle of 50 metres radius, towards left, when flying at 200 km per 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. Correct Answer 10.046 kN-m
Given : R = 50 m ; v = 200 km/hr = 55.6 m/s ; m = 400 kg ; k = 0.3 m ; N = 2400 r.p.m. or ω = 2π × 2400/60 = 251 rad/s We know that mass moment of inertia of the engine and the propeller, I = mk2 = 36 kg-m2 and angular velocity of precession, ωP = v/R = 55.6/50 = 1.11 rad/s We know that gyroscopic couple acting on the aircraft, C = I. ω. ωP = 36 × 251.4 × 1.11 = 100 46 N-m = 10.046 kN-m
মোঃ আরিফুল ইসলাম
Feb 20, 2025