Question

Hinge moment coefficient depends upon ________

(a) Tail AOA, elevator deflection, etc

(b) Only tail angle

(c) Only wing angle

(d) Lift to drag ratio of fuselage

I had been asked this question in homework.

My question is taken from Stick-Free Stability in chapter Stability, Control, and Handling Qualities of Aircraft Design

Answer 1

Correct choice is (a) Tail AOA, elevator deflection, etc

Best explanation: Hinge moment coefficient depends upon number of factors such as elevator deflection, angle of attack at tail, tail setting angle etc. Lift to drag ratio is defined as aerodynamic efficiency of the aircraft. Fuselage is primary drag producing member of the aircraft. Lift to drag ratio of the fuselage will be less.