What happened
On 13 February 2000, an SA3im41G Gazelle 1, registration G-UZEL, was conducting a private flight departing from a landing site in Kirk Michael, Isle of Man. At the start of the flight, the main fuel tank contained approximately 80 litres of fuel, while the auxiliary tank was at its full capacity of 90 litres. While the standard operating procedure required transferring fuel from the auxiliary tank to the main tank once levels dropped below 100 litres, the fuel transfer had not been initiated during the 25 minutes of flight time.
As a result, the engine ceased functioning because the main tank ran dry. The pilot attempted an autorotation into a nearby field. During the final moments before landing, the pilot increased collective control to steer clear of a stone wall. This maneuver caused the rotor RPM to decrease, leading to a heavy touchdown and a single bounce. During the impact, the main rotor blades struck the vertical stabilisers, causing damage to the stabiliser surfaces and creasing the rotor blade tip weight housings.
There were no fatalities and no injuries among the four occupants, all of whom exited the aircraft through the standard exits.
The investigation
The investigation examined the fuel management practices and the sequence of events leading to the engine failure. It was established that the engine relies solely on fuel supplied from the main tank. Investigators found that while the pilot was aware of the procedure to transfer fuel from the auxiliary tank, the transfer was sometimes delayed until a warning light appeared on the panel, indicating the main tank had reached a much lower level of 50 litres. At the time of the accident, the auxiliary tank remained full, indicating that the necessary fuel transfer had not occurred.