In-Flight Acoustic Emission Monitoring
A miniaturised acoustic emission (AE) monitoring system has been installed in a high performance jet trainer to monitor inflight growth of a known crack in a critical structural member. It has been demonstrated that valid AE can be collected even in this hostile environment. Spurious data from background noise have been eliminated using a suitable frequency bandpass and a zone-isolation technique. A linear correlation between valid AE and increase in crack length, measured independently using a magnetic rubber inspection technique, has been obtained. The AE data can also be used to characterise the aircrafts’ flight regime; most AE occurs under rapid dynamic loading conditions typical of low flying.
KeywordsAcoustic Emission Acoustic Emission Signal Acoustic Emission Event Monitor Unit Acoustic Emission Activity
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