Question

Rapid oscillations of control surface due to application of the air loads is termed as __________

(a) control surface flutter

(b) control surface span

(c) control surface trim

(d) control surface effectiveness

I have been asked this question in an interview.

Enquiry is from Control-Surface Sizing topic in portion Initial Sizing of Aircraft Design

Answer 1

Right answer is (a) control surface flutter

The best explanation: Rapid oscillation of control surface is called control surface flutter. This rapid oscillation can tear off the surface or wing/tail itself. This will induces excessive vibration as well. Effectiveness of control surface is measure of how effectively we can control the aircraft.