On February 3, 1985, a Hiller UH12E (registration N5323V) operated by Westside AG Aviation was involved in an aviation accident near Five Points, CA. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
A helicopter performing an agricultural flight lost power near max gross weight at low altitude. The pilot attempted landing on a dirt road but struck a canal embankment and rolled over. Engine examination revealed broken rod bolts and improper torque on cylinder bolts.
Accident Details
While conducting an agricultural flight, the helicopter experienced a sudden loss of engine power. At the time, the aircraft was operating near its maximum allowable gross weight and was between 3 and 5 feet above ground level. As the helicopter yawed left and descended, the pilot in command attempted to land on a small dirt road. The pilot missed the road, collided with the embankment of a canal, and the aircraft rolled over.
Engine Examination
Examination of the engine revealed that the rod bolts to the #1 connecting rod were broken. One of the nuts had backed off from the rod bolt. Further inspection of the bolts in the other five cylinders disclosed that none of them had been tightened in accordance with the manufacturer's overhaul specifications. The aircraft's owner performed the last major overhaul on the engine 907 hours prior to the accident.