Narrative:

During flight; as-350 helicopter crew experienced an annunciation of hydraulic system failure. The pilot followed procedures and declared an emergency. The pilot successfully landed the aircraft without incident. Maintenance conducted a quick examination and no visible signs of failure were evident. The as-350 helicopter was towed back to the hangar and placed in maintenance to determine the failure. This aircraft had the same occurrence the previous week. I was not aware of the prior event until I was called asking details and the maintenance performed; to return the aircraft to service.

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Original NASA ASRS Text

Title: A Quality Assurance Inspector reports about two events involving a Eurocopter AS-350 that experienced an inflight Hydraulic System Failure Warning Annunciation; requiring a shutdown of the aircraft's single hydraulic system and an emergency landing. Maintenance troubleshooting noted the hydraulic system was functioning properly; but the 'On/Off' Hydraulic System toggle switch detent on the Pilot's Collective handle was malfunctioning.

Narrative: During flight; AS-350 helicopter crew experienced an annunciation of Hydraulic System failure. The pilot followed procedures and declared an emergency. The pilot successfully landed the aircraft without incident. Maintenance conducted a quick examination and no visible signs of failure were evident. The AS-350 helicopter was towed back to the hangar and placed in Maintenance to determine the failure. This aircraft had the same occurrence the previous week. I was not aware of the prior event until I was called asking details and the maintenance performed; to return the aircraft to service.

Data retrieved from NASA's ASRS site as of July 2013 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.