LAX98LA309

The pilot was headed back to the airport, about 50 feet agl, and felt a strong vibration throughout the entire helicopter. The aircraft pitched up and gained about 50 to 75 feet of altitude and began to turn to the right. The pilot reported that he lowered the collective, applied full left cyclic, and leveled the aircraft. He stated that about 15 feet agl he lost control and the helicopter impacted the ground in a 30- to 45-degree left roll attitude. The pilot reported that the engine was still running for about 5 to 10 seconds after impact, then quit on its own. He stated that he had not experienced any malfunction with the aircraft prior to the accident. No discrepancies were found during an examination of the airframe, powerplant, and control systems.

On September 26, 1998, at 1100 hours Pacific daylight time, a Texas Helicopter Corporation OH-13H, N1001G, crashed in a field near Gilroy, California. The aircraft was destroyed and the commercial pilot, the sole occupant, was not injured. The flight was conducted under the provisions of 14 CFR Part 137 as an aerial application flight, and originated at the Hollister, California, airport, about 0700. Visual meteorological conditions prevailed and no flight plan was filed.

The pilot reported that he had finished spraying the field and was headed back to the airport, approximately 50 feet agl, when he felt a strong vibration throughout the entire helicopter. The aircraft pitched up and gained about 50 to 75 feet of altitude and began to turn to the right. The pilot reported that he lowered the collective, applied full left cyclic, and leveled the aircraft. He stated that the helicopter was then flying approximately 90 degrees to the original direction of flight. The pilot reported that about 15 feet agl, he lost control and the helicopter impacted the ground in a 30- to 45-degree left roll attitude. He stated that the engine ran for about 5 to 10 seconds after impact, then quit on its own. He reported that he had not experienced any malfunction with the aircraft prior to the accident.

The aircraft was examined following recovery. Control continuity was established from the cockpit to the respective actuators for the collective, cyclic, and antitorque systems. There was no evidence of object damage to the airplane or rotors. There was no catastrophic damage noted to the engine or engine accessories. Examination of the main rotor hub and assembly did not reveal any discrepancies.