U. S. Naval Technical Mission in Europe Technical Report No. 143-45, A German Supersonic Method of Testing Aircraft Bearings-Forwarding of.

摘要

A non-destructive method of detecting the presence of air bubbles between the lining and the main steel body of aircraft bearings was developed by the Deutsche Versuchsanstalt fur Luftfabrt. This method was based upon a measurement of the attenuation of a 10 megacycle sound beam as it passed through the bearing. The testing technique was simple and rapid and could detect air bubbles whose thicknesses were as small as millimeter (.004”).