What happened
On 17 March 2003, a DH82A Tiger Moth, registration G-ANEN, was conducting a private flight at Chichester (Goodwood). While climbing through 400 feet during the third circuit from Runway 14, the aircraft's engine RPM dropped from a standard 2,000 RPM to below 1,600 RPM.
Unable to sustain level flight due to the power loss, the pilot initiated a left turn to perform a forced landing on the grass Runway 24. The aircraft reached the runway and began to decelerate. In an attempt to prevent the aircraft from overrunning the runway, the pilot applied full left rudder. This maneuver caused the left lower wing to impact a runway marker before the aircraft came to a complete stop. There were no injuries to the crew during the incident, though the aircraft sustained damage including torn fabric on the left wing.
The investigation
The investigation focused on the cause of the engine power degradation and the subsequent ground maneuvers. Prior to takeoff, the pilot had verified that both the left and right magneto systems were functioning correctly. Post-accident inspections of the right magneto identified an engine RPM decrease that fell outside of normal operating parameters. While this finding was noted, investigators determined that this specific issue was not sufficient to account for the total loss of power experienced during the climb. The investigation established that replacing the associated spark plugs resolved the identified mechanical issue.