The diameters of the main rotor and tail rotor of a single-engine helicopter are 7.59 m and 0.98 m, respectively. The respective rotational speeds are 456 rev/min and 4143 rev/min. Calculate the speeds of the tips of both rotors.

Question

main rotor:
tail rotor:

Compare these speeds with the speed of sound, 343 m/s.

Answer 1

speedtip= w*r where w=2PI*rev/min*1min/60sec