Question

Which of the following is a correct form of fuel flow?

(a) C=C2θM^n

(b) C=C2θ^\(\frac{1}{2}\)M

(c) C=C2θM

(d) C=C2θ^\(\frac{1}{2}\)M^n

I got this question in an internship interview.

The question is from Cruising Performance in portion Cruising Performance of Aircraft Performance

Answer 1

The correct answer is (d) C=C2θ^\(\frac{1}{2}\)M^n

To explain: The correct formula for fuel flow is C=C2θ^\(\frac{1}{2}\)M^n where θ is the temperature, M is mach number and n varies from 0.2-0.6 for turbojet to turbofan. It depends on the bypass ratio of the combustion chamber.