What happened
On 9 July 2022, a Piper PA-46-350P, registration G-LAMI, was conducting a prospective buyer demonstration flight at Wycombe Airpark. The flight was intended to be an IFR departure towards Cardiff. During the takeoff roll on Runway 06, the pilot realized there was insufficient runway remaining to complete the maneuver and initiated a rejected takeoff.
As the aircraft decelerated, it crossed the end of the runway and entered a taxiway. The aircraft began to skid sideways, eventually veering 100 degrees from its original heading. The transition from the paved surface to the grass caused the main landing gear to collapse, resulting in damage to the left wing, the fuselage, and both landing gear assemblies. There were no fatalities and no injuries among the two crew members and four passengers on board.
The investigation
Investigators examined the aircraft's Garmin G1000 Integrated Flight Deck (IFD) data, which provided precise engine and positional parameters. The analysis revealed that the aircraft was significantly heavier than the pilot had calculated. While the pilot believed the aircraft was at its maximum takeoff weight, the actual takeoff weight was approximately 4,716 lb, which was 376 lb overweight.
This discrepancy stemmed from two primary errors: an underestimation of the combined weight of the crew and passengers, and a misidentification of the fuel quantity on board prior to refueling. Furthermore, the investigation found that the takeoff roll was compromised by the aircraft's starting position, which was over 100 ft from the runway threshold following a 180-degree turn, and the need to manage engine manifold pressure after a Master Warning was triggered by the pilot flying.
Findings
- The aircraft was operating significantly above its maximum takeoff weight due to inaccurate pre-flight weight and balance calculations.
- The aircraft was overweight due to the underestimation of passenger/crew mass and an error in recording the initial fuel quantity.
- Pre-flight preparations were likely compromised by perceived time pressure to depart.
- The takeoff roll was further extended by the pilot flying's lack of familiarity with the engine's manifold pressure limits, leading to a red warning and subsequent power reduction.
- The decision to reject the takeoff was necessitated by the insufficient remaining runway, though the investigation noted that continuing the takeoff might have resulted in an inability to clear trees at the end of the runway.