Incident Overview
On October 7, 2018, at 1340 eastern daylight time, an Enstrom F-28C helicopter registered as N5691Y sustained substantial damage following a hard landing after takeoff from a field in Bridgeville, Delaware. The commercial pilot and three passengers on board reported no injuries. The helicopter was operated by J&J Shop HeliAir LLC as a local sightseeing flight under Title 14 Code of Federal Regulations Part 91. Visual meteorological conditions prevailed, and no flight plan was filed.
Sequence of Events
According to the pilot, during takeoff near power lines and farm equipment, he increased the throttle to maximum engine and rotor rpm and initiated a climbing left turn. He subsequently observed a slight decay in rotor rpm. As the helicopter approached the power lines, the pilot slightly reduced collective pitch while increasing throttle in an attempt to restore rotor rpm, but these actions did not have the desired effect. Nearing the power lines, he pulled collective pitch, which further degraded the already low rotor rpm as the helicopter cleared the wires. After clearing the power lines at an altitude of approximately 50 to 75 feet above ground level, the engine and rotor rpms were well below minimums. With the helicopter descending, the pilot applied full collective just before impact, resulting in a hard touchdown.
Aircraft and Operator Information
The Enstrom F-28C is a three-seat helicopter powered by a Lycoming HIO-360-E1AD engine rated at 205 horsepower. Its most recent annual inspection was completed in August 2018. The operator, J&J Shop HeliAir LLC, held an FAA Letter of Authorization for commercial air tour operations under Part 91.147. According to the operator, company policy limited flights to a maximum of two passengers, but the accident flight carried three. Following the incident, the operator reiterated this policy to all personnel.
Investigation Findings
Federal Aviation Administration (FAA) inspectors examined the accident site. The helicopter came to rest upright approximately 1,000 feet northeast of the departure point. The tail boom had separated from the fuselage, causing substantial damage to the tail rotor drive shaft, tail boom, and tail rotors. Control continuity was verified for the throttle, cyclic, and collective systems. Subsequent examination and test run of the engine revealed no evidence of preimpact mechanical malfunctions or failures that would have prevented normal operation.
Pilot Information
The pilot held a commercial pilot certificate with helicopter and instrument helicopter ratings. His most recent second-class medical certificate was issued in September 2018. He reported a total flight experience of 1,864 hours, with 74 hours in the accident helicopter make and model. The pilot noted that he had conducted 12 previous passenger-carrying flights in the same helicopter without observing any abnormalities and was unaware of any mechanical issues during the accident flight.
Weather and Additional Information
Weather conditions reported at Dover Air Force Base, approximately 25 miles from the accident site, at 1332 included wind from 240 degrees at 6 knots, visibility 10 statute miles, scattered clouds at 2,400 feet above ground, temperature 28 degrees Celsius, and dew point 22 degrees Celsius. The pilot's operating handbook includes guidance for maximum power takeoffs from confined areas, which advises against over-pitching to prevent engine and rotor rpm decay.