What happened
On the evening of the incident, a Robinson R44 (registration G-JESI) departed from the K Club for a flight to Adare, Co Limerick, carrying the pilot and four passengers. During the preceding refueling process, which was conducted as a "hot refuelling" operation, the pilot noticed the fuel gauge rise to 20% before the reading ceased to increase. Assuming the gauge was malfunctioning, the pilot instructed the refueller to continue adding fuel until a target of 300 litres was reached. The pilot subsequently signed for 302 litres of fuel.
During the flight, at approximately 19:10 local time, the pilot noticed a slight surge in the engine and became concerned regarding the remaining fuel levels. This prompted a precautionary landing in a farm field located near the village of Dunkerrin, on the border of Offaly and Tipperary. All five occupants of the aircraft exited the helicopter without injury.
The investigation
An inspection of the aircraft the following morning revealed that the fuel tank held only 6.5 litres of fuel. Investigators found no evidence of a fuel leak, no fuel staining on the ground, and no structural damage to the aircraft. The investigation confirmed that the helicopter's fuel gauge was fully functional and that the fuel system was intact and leak-free.
Findings
- The investigation identified a significant discrepancy in the refueling process: only about 10 litres of the 302 litres requested were actually added to the aircraft.
- The primary cause of the fuel shortage was the failure to deliver the intended volume of fuel during the refueling operation.
- While the investigation could not determine why such a large discrepancy occurred between the signed docket and the actual fuel delivered, it was established that the pilot's reliance on a perceived faulty gauge led to the insufficient fuel load.