The aircraft had an amphibious capability and began the flight via a water takeoff. The landing was to be made on a beach on the other side of the island. The aircraft was observed flying parallel to the beach a few hundred metres from the shoreline and at an estimated altitude of 200-400 feet, when it rolled right and suddenly spiralled into the water. Some witnesses indicated that they heard the engine noise interrupted just before the aircraft rolled while others said that the noise remained constant. No abnormality was found in the aircraft or its engine which might have contributed to the accident. There was positive evidence that the engine was delivering power when the aircraft struck the water. The pilot indicated that he was winding down the landing gear as he flew parallel to the beach. This may have distracted him, allowing the airspeed to decrease. The flightpath of the aircraft into the water was typical of the post-stall behaviour of Drifter aircraft.