History of the Flight
On the morning of 27 August 2024, the pilot of G-CUBX, a Piper PA-18-150 Super Cub, used a remote-controlled aircraft tug to move the aircraft from its hangar. After completing pre-flight checks and initially struggling to start the engine, the pilot taxied for departure from Runway 28 at Croft Farm Airstrip (Defford Airfield), Worcester. CCTV footage captured the aircraft entering the runway with flaps retracted. During the initial takeoff roll at low speed, the aircraft swung left before being realigned. The remainder of the roll appeared normal, and the tailwheel lifted off just before the aircraft left the camera view.
Approximately nine seconds later, G-CUBX reappeared in the CCTV image in a steep nose-down attitude just before ground impact. Two eyewitnesses reported an initially steeper-than-expected climb with a normal engine note. One witness described a left wing drop and steep left turn at low height, followed by a descent and ground impact. The fire that broke out after impact started near the cockpit within three seconds.
Accident Site and Wreckage
The aircraft initially came to rest on its nose with the tail nearly vertical, but the tail settled during the post-crash fire. The fuselage was inverted with significant structural damage. Ground impact marks indicated the left wing tip struck first, pivoting the fuselage so the propeller spinner hit the ground. One propeller blade was embedded in the ground and showed twisting consistent with engine power at impact. Twigs from a nearby tree were caught in the tail wheel, indicating contact with tree tops.
A continuity check revealed all flight controls remained connected to their respective surfaces, except the right flap bell crank was missing and most of the flap had melted. The left flap had partially melted but remained attached with control cables intact. The left wing and struts stayed attached, while the right wing detached at the root. The right wing struts were bent and fire-damaged but remained attached.
A small patch of dead grass was found where the aircraft had been parked, likely from fuel drips during engine start attempts. A technician who assisted with starting reported fuel dripping onto the air box, indicating a possibly flooded engine. The technician noted that cranking periods were extended with minimal rest between attempts, which likely exacerbated starting difficulty.
Recorded Data
The pilot used a tablet with a flight-planning app that recorded GPS data. The ground track shows the aircraft lining up on the grass strip and beginning takeoff at 09:32:32 UTC. After initial gentle manoeuvres, the aircraft accelerated, veering slightly left. The tail rose after 10 seconds, and within two seconds the aircraft was airborne, climbing at an average flight path angle of 14° and reaching a maximum groundspeed of 34 kt. The aircraft then turned left, reducing climb rate and crossing the left edge of the strip at about 10 m height. The last reliable GPS position showed contact with a tree 40 m left of the strip at approximately 15 m height. The aircraft then rolled left and descended vertically, nose-down, wings aligned with the strip, striking the ground left wing first.
Aircraft Information
G-CUBX was a 1981 Piper PA18-150 Super Cub with a Lycoming O-320 engine. It had been previously registered in Greece and Germany before UK registration in 2021 as G-CLYI. The aircraft was modified with an Alaskan Bush kit including tundra tyres, heavy-duty landing gear, and a belly fuel tank. It had been involved in a landing accident in May 2023 that caused it to flip over. After 13 months of repairs, it was re-registered as G-CUBX in June 2024. Vortex generators were fitted to improve stall and STOL performance. A CAA Airworthiness Review Certificate was issued on 11 July 2024.
After repairs, the aircraft was returned to the workshop on 22 July 2024 because the owner reported a left roll in flight. Adjustment of the right wing aft strut corrected a 2.5° difference in wingtip incidence (washout), and the roll was eliminated. On 16 August 2024, ignition system problems (inoperative spark plugs, poor harness, timing issues) were fixed; engine ground runs confirmed correct function. The technician noted a slow deployment of something (unfinished sentence in source).