Question

What is the velocity of maximum specific air range of the engine when the maximum air speed is 400m/s and the exponential value is 0.2?

(a) 300.84

(b) 380.43

(c) 440.76

(d) 494.37

I had been asked this question in quiz.

This intriguing question comes from Cruising Performance topic in division Cruising Performance of Aircraft Performance

Answer 1

Correct choice is (d) 494.37

To explain I would say: The answer is 494.37.

Given n=0.2, Vmd=400m/s. From the formula \(\big[\frac{3-n}{1+n}\big]^{\frac{1}{4}}\)Vmd. On substituting the values we get \([\frac{3-0.2}{1+0.2}]^{\frac{1}{4}}\)*400=494.37.