WPR19LA002

Shortly after takeoff, as the pilot turned the helicopter onto the crosswind leg of the traffic pattern, he noticed an “immediate low rotor speed,” a loss of engine power, and the helicopter yawed to the left. The pilot increased power; however, both the engine and rotor rpm continued to decrease rapidly. The pilot lowered the collective to regain and maintain rotor rpm and initiated an autorotation to an agricultural field. The helicopter landed hard, and a rotor blade severed the tail boom. The pilot stated that he experienced the same malfunctions twice during a flight about 3 months before the accident (low rotor speed and loss of engine power). During this flight, he was able to land the helicopter without incident. A postaccident examination of the helicopter revealed faulty wiring to the engine governor. Because of the faulty wiring, the governor was likely unable to sense rotor and engine rpm and make the necessary adjustments to keep rotor rpm constant, resulting in a loss of engine power.

On October 6, 2018, at 1437 Pacific daylight time, a Robinson Helicopter Company R44 II, N611TH, was substantially damaged when it was involved in an accident near Salinas, California. The pilot was not injured. The helicopter was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, as he turned the helicopter onto the crosswind leg of the traffic pattern shortly after takeoff, he noticed an “immediate low rotor speed,” a loss of engine power, and the helicopter yawed to the left. The helicopter was at an altitude of 600 ft mean sea level. The pilot increased power; however, both the engine and rotor rpm continued to decrease rapidly. The pilot lowered the collective to regain and maintain rotor rpm and initiated an autorotation to an agricultural field. The helicopter landed hard, and a rotor blade severed the tail boom. The pilot stated that he experienced the same malfunctions twice during a flight on July 25, 2018 (low rotor speed and loss of engine power). During this flight, he was able to land the helicopter without incident. A postaccident examination of the helicopter revealed faulty wiring to the engine governor. According to a mechanic who conducted the examination, the wiring was “cut and stripped by an automatic machine at the Robinson factory.”