Accident Details
On July 29, 2014, at 1651 eastern daylight time, a Hughes 369D helicopter, registered as N89ZC, collided with terrain following a loss of engine power. The accident occurred in West Liberty, Ohio, while the helicopter was engaged in tree trimming operations. The commercial pilot sustained serious injuries, and the helicopter sustained substantial damage. The aircraft was registered to DAH Aircraft LLC and operated by Rotor Blade LLC as a 14 Code of Federal Regulations Part 133 external load flight. Visual meteorological conditions prevailed, and the flight did not operate on a flight plan. The local flight originated from a nearby field at 1501.
Pilot and Witness Accounts
The pilot was using a 10-bladed aerial saw to trim trees along a railroad track at the time of the accident. A witness reported that the engine sounded like it lost power, and the tail of the helicopter oscillated to the left as the helicopter began losing altitude. The helicopter then rolled to the left and descended, impacting trees and terrain.
Postaccident Examination
A postaccident examination was conducted by a Federal Aviation Administration inspector. The inspector found that the tail boom had separated from the helicopter during the impact. The tail rotor drive shaft showed no evidence of torsional twisting. The main and tail rotor blades sustained little damage. There was no evidence of fuel spill at the accident site. The helicopter's fuel system was intact, but no fuel was present in the fuel tank or in the fuel line at the engine. When electrical power was applied, the fuel quantity indicator showed the tank was empty.
Fuel Management
The helicopter was topped off with fuel prior to the flight. According to the helicopter operator, the helicopter holds 62.4 gallons of fuel. The pilot reported the helicopter consumes about 30 gallons per hour. The operator stated that spot tracker information indicated the helicopter flew 1 hour and 50 minutes from the last fueling to the time of the accident. After the accident, approximately one quart of fuel was drained from the helicopter. The operator stated that pilots and ground crew time the flights for fuel consumption. The ground crew gave the pilot a one-hour time check, followed by additional 15-minute time checks prior to the accident.