Question

Turbofan engine uses a large fan at inlet to ________

(a) increase efficiency of the engine

(b) increase flow velocity

(c) increase wing tip lift

(d) increase tailplane lift

I got this question during an interview for a job.

My question is from Propulsion in division Propulsion of Aircraft Design

Answer 1

Right answer is (a) increase efficiency of the engine

The explanation is: To Increase efficiency, more specifically propulsive efficiency of the engine a turbofan engine uses a fan. Some air is bypassed around the engine and not being used for combustion. This helps to increase efficiency.