Thread cutter type testing device for detecting presence of crack in e.g. wing of airplane, has track forming spiral turn that forms oscillating circuit generating resonant frequency, where measured value of frequency is varied

摘要

The device (1) has a breakable dielectric substrate (3) fixed on an electricity conducting structure, and an electricity conducting track (4) covering the substrate. The substrate and the track are broken after generation of crack in the structure when the covered substrate is fixed on the structure. The track forms a spiral turn forming an oscillating circuit generating resonant frequency, where measured value of the frequency is varied based on a position of the covered substrate with respect to the structure. An independent claim is also included for a method for inspecting an electricity conducting structure of an aircraft.