Overview
On 13 May 2023 at 1415 UTC, a Piper PA-18-150, registration G-CLYI, experienced a loss of control during a landing at Sleap Aerodrome in Shropshire. The aircraft, equipped with large bush wheels and a large propeller to enhance short takeoff and landing (STOL) performance, was being flown by the sole occupant, a 22-year-old private pilot with 610 hours total flying experience, including 32 hours on type.
History of the Flight
The aircraft was participating in a STOL event at the aerodrome. During the approach, G-CLYI was positioned to land on a grass strip adjacent to the left edge of Runway 18. The pilot reported that after touchdown on the main wheels, he applied gentle braking. As the aircraft slowed below 10 kt with the tailwheel still off the ground, the wind shifted to a light tailwind, causing the tail to lift further. The pilot attempted to apply a brief burst of throttle to raise the nose, but this was ineffective. As the tail continued to rise, he reduced the throttle to idle and turned off the magnetos. The propeller then struck the ground, and the aircraft tipped onto its nose and then onto its back. The pilot shut down the electrical system and fuel, then exited the aircraft uninjured. The propeller, windscreen, rudder strut, and other struts sustained damage.
STOL Event and Aerodrome Context
The STOL event was advertised only to members and other pilots, not to the public. The pilot, who also served as the airfield accountable manager, had been supervising adjudicators on the ground before taking a flight to perform a STOL landing. The wind at the time was light and variable. Video evidence showed two people adjacent to a line of cones at the touchdown point and two further people where the aircraft tipped over; these individuals were adjudicating the event.
Runway 18/36 at Sleap Aerodrome is 18 m wide, with a required runway edge strip of 30 m from the centreline. A line of cones was placed 45 m from the runway centreline, delineating the aircraft parking area to the east from the runway and its edge strip. The grass strip used for the STOL landing was part of the runway edge strip, not a licensed runway.
Analysis and Safety Actions
The AAIB analysis indicated that it was likely the aircraft landed with a tailwind and that braking, combined with this tailwind, caused the loss of control. The positions of adjudicators were beyond the limit of the runway edge strip, but the use of the grass strip reduced the effectiveness of separation measures between people and the aircraft. The pilot, as accountable manager, acknowledged that during his flight he had not properly controlled ground personnel or delegated responsibilities. Several safety actions were identified and implemented: appointment of a deputy for events, integration of risk management into event planning within the Safety Management System (SMS), nomination of a separate safety officer for events, and collaboration with experienced event planners and flying display directors. The aerodrome's SMS was updated, and the airfield manager obtained a Tier 1 Flying Display Director accreditation.
Conclusion
The aircraft pitched over because of a combination of a light tailwind and braking to achieve a short landing.