What happened
On 19 December 2005, a Piper PA-28-140 Cherokee, registration G-ASPK, was completing a solo directional control training exercise at Land’s End Airfield in Cornwall. The weather conditions featured a light south-westerly wind of approximately five knots, with good visibility and a cloud base of 2,200 ft amsl. The aircraft was operating on Runway 25, a grass runway.
Following a stable approach at a speed between 80 and 85 mph with full flaps, the aircraft touched down on the damp grass surface further along the runway than usual. The student pilot maintained idle power and allowed the aircraft to decelerate to roughly 40 mph before engaging the hand-operated brakes. Upon braking, the aircraft suddenly veered to the left at an angle of approximately 30 degrees. In an attempt to correct the deviation, the pilot applied right rudder, but the aircraft continued toward a boundary hedge. The pilot applied the brakes again, which caused the aircraft to veer even further left, eventually striking the hedge at approximately 25 mph. The aircraft sustained damage to the nose landing gear, engine cowling, wings, spinner, and windscreen, though no fire occurred and the pilot escaped uninjured.
The investigation
The investigation examined the aircraft's braking system and the surface conditions of the runway. An inspection of the brakes confirmed they were functioning correctly and applying pressure evenly to both main wheels. Witnesses at the airfield provided varying accounts; one observer noted the aircraft appeared to be in a steady, continuous leftward turn, while an instructor suggested the combination of landing speed and runway conditions might have necessitated a go-around.
Findings
- The aircraft's tracks on the grass surface indicated a continuous turn to the left.
- The pilot could not definitively explain the cause of the leftward veer, though he considered the possibility of uneven braking due to the damp grass or improper rudder input.
- The aircraft veered left following the application of brakes on a damp grass surface.