Question

An aircraft is climbing and accelerating to reach the cruise mach number of 0.75. If aircraft is accelerating from 0.1M then, what will be the mission segment fuel fraction for this mission?

(a) 0.9821

(b) 0.9258

(c) 0.5289

(d) 0.28958

I have been asked this question during an internship interview.

My enquiry is from Rubber-Engine Sizing topic in portion Initial Sizing of Aircraft Design

Answer 1

Correct choice is (a) 0.9821

Best explanation: Given, after acceleration mach number = 0.75

For given subsonic mission segment fuel fraction,

= 1.0065 – 0.0325M = 1.0065 – 0.0325*0.75 = 0.9821.