The pilot had been carrying out crop spraying operations, and was hurrying to return to his base before last light. He was concerned with the fuel state, and made an enroute landing, where one of the passengers dipped the tank. Believing that adequate fuel remained, the pilot took off again, but shortly afterwards the engine lost all power. During the subsequent autorotation, manoeuvring was necessary to avoid power lines. The helicopter then landed heavily and the main rotor blades struck and severed the tail boom. It was determined that at the time of the accident the aircraft had been operating for 7 minutes longer than the expected total endurance. The pilot had not kept an accurate record of fuel usage, and it was likely that his decision making processes had been impaired by fatigue. It was probable that the helicopter had been resting on sloping ground at the time the tank contents were checked, resulting in an erroneous reading on the dipstick.
