When the aircraft arrived over the airstrip the surface wind was at a speed of 10 to 15 knots and varying in direction between south west and north west. The strip is situated on an exposed ridge and aligned north and south. The aircraft made two left circuits on each occasion descending to a low height along the strip to the north. After a third left circuit the aircraft again made an approach into the north and on this occasion landed, touching in the centre and 750 feet beyond the threshold of the 1, 875 feet long strip. The aircraft ran straight for approximately 300 feet and then veered to the left. Before reaching the left side of the strip the aircraft turned to the right and power was heard to increase markedly. The aircraft accelerated across the strip in a north easterly direction until it left the strip and struck an earth bank passing through it some nine inches from the top. It became airborne where the ground dropped away beside the strip and in a semi-stalled condition it flew for about 260 feet maintaining a mean 4 degrees descent down the hillside until it struck a large tree which tore off the left wing and the aircraft finally came to rest some 600 feet from the strip. The pilot suffered from an orthopaedic disability and wore a caliper on his left leg. The aircraft was fitted with a leather strap on the right rudder pedal which enabled the pilot to apply left rudder by pulling with his right foot. His licence restricted him to flying PA. 28 aircraft and he had demonstrated his competence at private licence standard.