What happened
On 15 April 2014, a Robin DR400/120, registration G-BKDJ, was conducting a private flight from Gloucestershire Airport toward Ross-on-Wye. After approximately ten minutes of flight, the engine power decreased and eventually ceased. While attempting to return to the airfield, the pilot observed that the low fuel pressure light had illuminated, though the low fuel quantity warning light remained extinguished.
Following unsuccessful attempts to restart the engine, the pilot established a glide at 75 knots and identified a suitable field for an emergency landing. After briefing the two passengers, the pilot executed a forced landing in a ploughed field. During the landing, the aircraft struck the ground on its left main gear, causing the aircraft to slew and the nose landing gear to collapse. There were no fatalities and no injuries to the crew or passengers, though the aircraft sustained damage to the propeller, cowling, front bulkhead, and nose leg.
The investigation
The investigation focused on the cause of the engine failure and the accuracy of the fuel monitoring prior to takeoff. The pilot had manually checked the fuel level using a dipstick, which indicated the tank was between one-third and one-half full. The cockpit gauge also supported this reading. However, post-accident inspections of the aircraft revealed that only approximately 5 litres of fuel remained in the tank, a level near or below the unusable fuel limit.
Findings
- The engine failure was caused by fuel exhaustion.
- The fuel quantity indicator sender was found to be defective, resulting in an over-reading of the actual fuel remaining.
- The flexible metal strip used for manual fuel dipping may have provided an inaccurate measurement of the fuel level.