The pilot had arranged to take some friends for a flight and to have a flight check with a flying instructor beforehand. Initially the instructor was unhappy with the pilot's circuit planning and landings. The pilot was given some information on the aircraft and a circuit diagram and another check was scheduled for the following day. On the next day the instructor gave the pilot a substantial briefing prior to the flight. The pilot's flying had improved significantly and the instructor assessed him as competent to fly the aircraft. After a scenic flight in the local area the aircraft joined the circuit on right downwind for runway 12. Surface wind at the time was 120` at 15 knots. The aircraft was observed to touchdown aligned with the centreline, near the runway threshold, and a short time later was seen to bank left. It touched down on the grass within the left hand side flight strip heading about 40` to the left of the runway direction. At around this time the pilot elected to go-around and he applied full power. From this point the aircraft made a gentle left turn until it was tracking 330`. Initial impact with the ground occurred when the aircraft was descending at an angle of approximately 15` and banked at least 30` to the left. Indicated airspeed at this time was 35 knots. The aircraft landed heavily on the nosegear and rolled backwards before coming to rest 20 metres from the point of initial impact.