What happened
On 5 August 2016, a Piper PA-22-150 Tri-Pacer, registration N6830B, was conducting a private flight when the engine experienced a sudden reduction in power. While cruising at an altitude of approximately 1,700 ft amsl, the pilot engaged the carburettor heat, at which point the engine RPM dropped from 2,300 to 1,500. Attempts to rectify the issue by turning the carburettor heat off, adjusting the throttle, or switching fuel tanks proved unsuccessful.
Following the power loss, the pilot notified Yeovilton Radar of the emergency and prepared for an off-field landing. The aircraft reached a field at Wyke Oliver Farm, near Weymouth, Dorset. During the landing sequence, the aircraft touched down at 60 mph but bounced back into the air after encountering an uneven surface. Upon the second touchdown, the pilot applied the brakes, but the aircraft could not be stopped before striking an obstacle, which caused the plane to overturn onto its back. The three occupants, including the pilot and two passengers, sustained minor injuries and were able to exit the aircraft through the standard exits. The aircraft suffered extensive damage.
The investigation
The investigation was based on the aircraft accident report submitted by the pilot. Investigators examined the sequence of cockpit actions and the flight path leading to the impact. The investigation focused on the engine's performance following the activation of the carburettor heat and the physical circumstances of the landing in the field.