What happened
On 22 July 2012, a Zenair CH 601XL Zodiac, registration G-CDJM, was conducting a private flight from Little Snoring, Norfolk. The weather conditions were clear with temperatures around 23°C and moderate surface winds. Approximately fifteen minutes into the flight, while cruising at 1,500 ft, the engine began running roughly and lost power.
In an attempt to manage the situation, the pilot applied carburettor heat and activated the electric fuel pump. Despite switching the fuel feed from the left tank to the right tank—noting that both tanks appeared to be one third full—the engine continued to lose power. The pilot identified a disused runway at Langham as a potential landing site. However, the engine ceased functioning entirely while the aircraft was at an altitude of approximately 50 ft over a wheat field.
As the aircraft contacted the crops, the nose pitched downward, causing the plane to invert and come to a rapid halt within roughly 15 metres. While the two occupants escaped without injuries, the impact caused the cockpit floor to distort, which severely obstructed their exit. The aircraft sustained extensive damage to the wings, engine components, fuselage, and cockpit area.
The investigation
The investigation focused on the cause of the engine failure and the subsequent impact. Investigators examined the fuel system and the cockpit area. The distortion of the cockpit floor was found to have trapped the main fuel line, which prevented a post-accident inspection of the fuel flow. The pilot's records indicated that the aircraft had been refuelled with AVGAS 100LL earlier that day, with a total of 40 litres on board, providing roughly two hours of flight time plus reserves.
Findings
- The engine power loss was initially characterized by rough running followed by a complete stoppage.
- The pilot attempted standard procedures to address potential fuel issues, including using carburettor heat and switching fuel tanks.
- The cause of the fuel starvation could not be definitively determined due to the damage to the fuel line preventing a flow check.
- The aircraft's inversion and the structural deformation of the cockpit floor made egress extremely difficult for the occupants.