On October 11, 1990, a Bell 47G4 (registration N477JM) operated by John W. Myers was involved in an aviation accident near Merced, CA. Investigators recorded the probable cause as: LOSS OF ENGINE POWER FOR AN UNDETERMINED REASON. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter on a business flight experienced an engine stoppage after washing. The pilot attempted an autorotative descent, but the helicopter landed hard and caught fire. Post-accident examination found no preimpact mechanical malfunction or failure.
Accident Details
After washing the helicopter, the pilot took off for a business flight over his ranch. During the flight, a ground witness heard the engine stop. The witness then observed the helicopter enter an autorotative descent. The helicopter subsequently landed hard and burst into flames. The witness estimated that the helicopter's altitude was approximately 50 feet above the ground at the time of initial observation.
Post-Accident Examination
A thorough post-accident examination of both the helicopter and its engine was conducted. The examination revealed no evidence of any preimpact mechanical malfunction or failure. The exact cause of the engine stoppage was not determined by the investigation.
Outcome
The helicopter sustained significant damage due to the hard landing and subsequent fire. No information was provided regarding injuries or fatalities.