Question

Which of the following is correct?

(a) Fuel weight fraction is based on mission profile only

(b) Take-off gross weight is sum of all possible weight of aircraft

(c) Empty weight fraction is always 0.55

(d) Crew load is always half of payload

This question was addressed to me in examination.

The doubt is from Conceptual Sketch Sizing topic in chapter Conceptual Sketch Sizing of Aircraft Design

Answer 1

Right answer is (b) Take-off gross weight is sum of all possible weight of aircraft

To explain I would say: Fuel weight fraction is affected by mission profile, aerodynamics of aircraft, engine type etc. Empty weight fraction will be different for different type of aircraft. Crew load and payload will be based on mission specifications.