What happened
On 21 July 2017, a Piper PA 24, registration N7456P, was conducting a private flight from Leeds East Airport to Retford (Gamston) Airport for the purpose of a touch-and-go landing. The aircraft was accompanied by a flight instructor acting as an observer. During the approach to Runway 21, the pilot utilized an intermediate flap setting and adjusted airspeed to manage a crosswind component.
As the aircraft descended, the crew encountered increasing turbulence. At approximately 100 ft altitude, the airspeed dropped by roughly 10 knots. While the pilot initially managed to correct a slight sink, a more significant downdraught occurred at approximately 20 ft altitude. Despite an attempt to increase power, the stall warning activated. The pilot responded by pushing the control column forward, but the aircraft struck the runway with significant force, landing nose-first.
Upon impact, the nose landing gear collapsed, causing the aircraft to skid along the runway. The propeller struck the ground, resulting in a shock-load to the engine. The main landing gear subsequently collapsed before the aircraft came to a complete stop. There were no injuries to the two occupants, who evacuated the aircraft safely.
The investigation
The investigation examined the meteorological conditions and the aircraft's flight path. The pilot noted that the aircraft was flying in the lee of airport buildings and tall trees, which may have contributed to a rotor effect. While the initial wind forecast was 180º at 14 kt, the airport rescue service recorded a wind of 150º at 17 kt following the accident. The investigation also considered the impact of airport infrastructure on wind stability.
Findings
- The primary cause of the accident was the encounter with downdraughting air shortly before touchdown.
- The aircraft's position in the lee of airport buildings and trees likely created localized windshear or rotor effects.
- The heavy nose-first impact led to the collapse of the nose landing gear and subsequent damage to the propeller and engine.