I had flown many recent hours and was very current in this aeroplane. I decided to visit a friend who ran a farm in an isolated area at about 2,000 ft AMSL. It wasn't a hot day but the weather was warm and from memory the QNH wasn't particularly low. The private strip on the farm had a row of pine trees about 80 ft tall along the eastern side of the roughly north - south strip.
There was a slight crosswind of less than 5 km from the east and the possibility, almost certainty, of at least some turbulence at the strip was recognized, however, no turbulence was encountered during an uneventful (solo) wheeler landing in the tail wheel aircraft.
Immediately after landing, the 105 kg farmer boarded for a flight over the local area and the farm to see the property from the air and to take some photos. No turbulence was encountered on take-off or during the short flight.
A normal approach and final was flown into the same strip. Immediately prior to the planned three point landing at about 4 ft AGL, the right wing dropped resulting in a heavy landing on the right undercarriage leg.
The aircraft would not track straight, with full right rudder and full right brake applied, the aircraft was curving to the left towards the row of trees. Application of power resulted in better rudder authority and a slight reduction of the curvature of the aircraft's path towards the trees. A delicate balancing act followed where I was judging the length of the curved path versus the braking distance between me and the rapidly approaching trees. I was lucky, I managed to stop before hitting the trees but my aircraft had sustained substantial damage to the fuselage frame and a bent right undercarriage leg.
Probable cause:
I may have been a bit slow on approach and I may have been getting towards the back of the power curve.
I may have misjudged the approach speed at higher than normal altitude with a heavier than usual passenger. I suspect that all of the above were contributory factors to some degree , but this aircraft has a strong tendency to drop its left wing in stalls with power on or off. As a result, I think that mechanical turbulence caused by the trees was the major cause of the wing drop and the heavy landing.
