On April 27, 1986, a Hiller UH12E (registration N5374V) operated by Douglas E. Walker was involved in an aviation accident near Castroville, CA. This summary draws on records from the U.S. National Transportation Safety Board (NTSB) historical archive.
During a forced landing following a tail rotor blade separation, a helicopter landed hard and rolled over after the landing skid failed.
Narrative
The pilot reported cruising at 500 feet above ground level over an open field when a loud bang was heard. The helicopter began to vibrate severely and spiral to the right. The pilot lost ground reference in the pre-dawn darkness after turning on the lights. Not wanting to land too hard, the pilot elected to leave the engine running and did not autorotate. The aircraft landed hard and rolled over after the landing skid failed.
Investigation
Investigation indicated that one tail rotor blade had separated at the tension torsion strap attach bolt hole. This is the transition area where the blade root casting and sheet metal blade skin are joined. The fracture surface of the casting appeared to be overloaded with no apparent indication of fatigue. The outboard blade section showed no indication of foreign object contact. All components of the helicopter were located in the impact area except one tail rotor blade.