Question

If a propeller has speed of 600 rpm and diameter of 1.2m and velocity of 10m/s. Find advance ratio.

(a) 0.83

(b) 0.39

(c) 0.289

(d) 0.1

The question was posed to me during a job interview.

The origin of the question is Propulsion in chapter Propulsion of Aircraft Design

Answer 1

Right answer is (a) 0.83

For explanation: Advance ratio = velocity*60 / (rpm*diameter)

= 10*60 / (600*1.2) = 0.83.