AAIB investigation to Sud Aviation SA342J Gazelle, YU-HET

During a maintenance check the helicopter inadvertently became airborne and landed heavily, Stapleford Aerodrome, 6 July 2015.


The helicopter inadvertently became airborne during a hydraulic system check with the engine running. It was not possible to determine why the helicopter became airborne. During the investigation it was found that the pressure switch was not fitted to the hydraulic pack and hence the low hydraulic pressure warning would not activate. A safety concern relating to the overhaul of the engine was also identified.

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Sud Aviation SA342J Gazelle, YU-HET 11-16

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Glossary of abbreviations

Published 10 November 2016