Investigators, 2004. 2CVR Recordings of Explosions and Structural Failure Decompressions

Rapid identification of the cause of failure is a high priority in the immediate aftermath of a major civil aircraft accident. Attention is often focused on the two recorders, the Cockpit Voice Recorder (CVR) and flight data recorder. In the event of sudden, catastrophic loss of an aircraft through explosions or structural failure decompressions, the recordings are seen as even more important. Yet these recorders are not designed to record such events with great fidelity and the ability of accident investigators to interpret such recordings has been severely tested in several major accidents in the past thirty years; comparisons between accident recordings have not been able to produce conclusive results. This paper reports on a programme investigating CVR recordings of explosions and rapid decompressions on a variety of aircraft from trials in several countries. In particular we show that CVR recordings are generally unable to discriminate between explosions and structural failure decompressions and we explain why this is so. We shall also put forward practical suggestions for systems that may be able to record these events with greater fidelity and which would provide investigators in the future with tools to locate the seat of the failure