Question

Which of the following is correct?

(a) Drag due to air spilled before entering into the inlet is called additive drag

(b) Lift is always equal to drag

(c) Thrust loading is same as wing loading

(d) Drag and lift are always unity

I have been asked this question by my college professor while I was bunking the class.

Question is from Propulsion in division Propulsion of Aircraft Design

Answer 1

Right option is (a) Drag due to air spilled before entering into the inlet is called additive drag

To elaborate: Additive drag is drag produced due to air spilled before entering into the inlet. Lift is not always equal to drag of the body. Thrust loading and wing loading both are two different terms and their physical significance is also different. It is not necessarily that drag and lift will be always unity.