The purpose of the flight was to allow the passenger to decide whether he would undertake flying training on ultralight aircraft. After take-off, the pilot flew the aircraft along the coast to the north of the DEPARTURE strip, before returning by the same route. Approaching Moonee Beach the pilot climbed the aircraft to about 500 feet over the water. The aircraft then entered a wing-over type of manoeuvre, followed by a steep dive to a height of about 150 feet above the sea. A pull-out was made but as the aircraft climbed steeply the left wing failed and folded back against the fuselage. The pilot attempted unsuccessfully to deploy the emergency parachute and the aircraft fell into the sea about 30 metres from shore. The passenger was able to release his harness as the aircraft sank, and after trying for some time to locate the pilot in the wreckage he swam to the beach. The body of the pilot was recovered the following day. A detailed examination of the wreckage revealed no evidence of any pre-existing defect that might have contributed to the accident. It was evident that the steep dive and subsequent pull-out manoeuvre had exceeded the structural limits of the aircraft design.