Resonance Tests: Their History and Principles in Relation to Flutter Problems

THOUGH resonance tests are now becoming familiar to most aeronautical engineers, it is perhaps desirable at the outset to indicate their general nature. They are vibration tests carried out on an aeroplane with the immediate object of determining the natural frequencies and modes of its parts, and in particular, of its wings. The ultimate aim of resonance tests on a given aeroplane is to provide data to assist in the estimation of its critical flutter speeds, so that its liability to flutter troubles may be assessed.