ERA17LA209

The commercial pilot was conducting long line operations in the helicopter, and he was flying it in an aft or left attitude with a higher nose-up attitude than normal flight to compensate for the load's drag. He then transitioned the helicopter to a 100-ft hover over a landing zone, and shortly thereafter, the helicopter experienced a total loss of engine power. Subsequently, the pilot initiated an autorotation, and during the landing, a main rotor blade contacted and severed the tailboom. Postaccident wreckage examination, which included a successful test-run of the engine, did not reveal evidence of any preimpact mechanical malfunctions or failures that would have precluded normal operation. However, when the helicopter was positioned nose up with the remaining fuel onboard (about 7 gallons in each tank), the low fuel light illuminated. The two fuel tanks were connected by an interconnect passage, and each tank had an internal baffle. The fuel pickup was located in the right front portion of the left fuel tank. Given that the low fuel light illuminated when the helicopter was positioned nose up, it is likely that the helicopter's nose-up attitude during the long line operation led to the unporting of the remaining fuel, which resulted in fuel starvation. The operator's risk assessment form required that pilots land the helicopter with at least about 14.7 gallons of fuel remaining for long line operations. After the accident, the operator amended its risk assessment form to require the same fuel requirement as side pull operations (about 37 gallons of fuel remaining upon landing) for long line operations.

On June 23, 2017, about 1315 eastern daylight time, a Hughes 369E, N765KV, operated by Haverfield Aviation Inc, was substantially damaged during a hard landing near Dennis, West Virginia. The commercial pilot was not injured. The external load flight was conducted under the provisions of Title 14 Code of Federal Regulations Part 133. Visual meteorological conditions prevailed and no flight plan was filed for the local flight.The pilot reported that he returned to the landing zone with a conductor attached to a long line. The helicopter was in a 100-foot hover over the landing zone, while the pilot monitored a ground crewmember tasked to disconnect the conductor from the long line. The helicopter began to settle and the pilot raised the collective control; however, the helicopter continued to settle as a warning horn sounded and the engine noise ceased. The pilot then entered an autorotation and during the landing, a main rotor blade contacted the tailboom, which resulted in a tailboom separation. The pilot added that prior to the hover, he was pulling the conductor with the helicopter in an aft or left attitude. He estimated that the loss of engine power occurred 45 seconds to 1 minute after transitioning from the pull to a hover. A Federal Aviation Administration (FAA) inspector witnessed a subsequent wreckage examination, which included a successful test-run of the engine. No preimpact mechanical malfunctions were noted and the low fuel light illuminated when the helicopter was positioned nose-up with the remaining fuel onboard. The inspector added that approximately 7 gallons of fuel remained in each of the two fuel tanks at the time of the loss of engine power. The two fuel tanks were connected by an interconnect passage and each tank had an internal baffle. The fuel pickup was located in the right front portion of the left fuel tank. The FAA inspector further stated that during the accident flight, the conductor was not completely off the ground and was being dragged over terrain. To compensate for the dragging resistance, the pilot had the helicopter in an aft or left attitude, with a higher nose-up attitude than normal flight. The operator's risk assessment form required that the helicopter be topped off (64 gallons) with fuel prior to and only fly for 1 hour during side pull operations, which would leave about 37 gallons of fuel remaining. For all other operations, including long line operations, the fuel requirement was to land with at least 100 lbs. (about 14.7 gallons) of fuel remaining. At the time of the accident, the helicopter had about 14 gallons of fuel remaining. After the accident, the operator amended its risk assessment form to include the same fuel requirement in long line operations as side pull operations.