Incident Overview
On January 22, 2013, at approximately 1400 mountain standard time, a Goetz Helicycle, registration N143PG, experienced a hard landing after performing an off-airport autorotation about 4 miles southeast of Falcon Field Airport (FFZ) in Mesa, Arizona. The commercial pilot, who was the sole occupant, was not injured. The aircraft was registered to and operated by the pilot under 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed, and no flight plan had been filed for the flight, which originated from Chandler Municipal Airport (CHD) in Chandler, Arizona.
Flight and Emergency Sequence
The pilot reported that he had hovered the helicycle for approximately 15 minutes before conducting a normal takeoff. During the flight, the engine suddenly lost partial power. The pilot initiated an emergency landing onto a residential road. A witness stated that his attention was first drawn to the helicycle when he heard the engine cutting in and out. Once the helicycle came into view, he observed it oscillating. The aircraft circled over his neighborhood before beginning an autorotation to the ground. The helicycle landed hard and came to rest in a bush. During the accident sequence, the tailboom and tail rotor assembly sustained substantial damage.
Post-Accident Examination
A post-accident examination of the airframe and engine by a Federal Aviation Administration Inspector revealed that the fuel controller actuator motor arm was in the minimum fuel position. The electronic speed controller unit was damaged and separated from the helicycle. Several wires from this system were pulled from their ring terminals, including the "B" wire, which runs to the fuel controller actuator motor. All of these wires showed signs of being mechanically pulled from the ring terminal, except the "B" wire, which did not exhibit the same rough and tension markings.
Pilot's Account and Causal Factors
The pilot reported that the "B" wire had come loose at the connection while in flight. He further stated that when power to the fuel controller actuator motor is lost, the engine automatically goes to a minimum fuel stop position and flight idle. The pilot noted that there were no parts failures, but he had installed the "B" wire without an additional strain relief at the connector, which allowed the wire to disconnect from the system during normal operations. The pilot reported that the accident can be prevented by installing a second parallel wire between the fuel controller actuator motor and the electronic speed controller unit.