Question

The rate of climb is given by _____________

(a) [ηP+DV]\(\frac{1}{W}\)=\(\frac{dH}{dt}\)

(b) [ηP-DV]\(\frac{1}{W}\)=\(\frac{dH}{dt}\)

(c) [ηP+DV]W=\(\frac{dH}{dt}\)

(d) [ηP-DV]W=\(\frac{dH}{dt}\)

The question was posed to me during an online interview.

My question is taken from Climb and Descent Performance with Power-Producing Engines topic in chapter Climb and Descent Performance of Aircraft Performance

Answer 1

The correct answer is (b) [ηP-DV]\(\frac{1}{W}\)=\(\frac{dH}{dt}\)

The best I can explain: The rate of climb is given by [ηP-DV]\(\frac{1}{W}\)=\(\frac{dH}{dt}\) where η is propeller efficiency, P is power, V is velocity, D is drag and W is weight and dH/dt is vertical velocity. The rate of climb is maximum when power speed is minimum.