Loss of control

Aircraft crashed into rice crop at high speed in a 30 deg nose down wings level attitude in fog. Cause undertermined.

The pilot commenced aerial spraying operations at about 0620 hours and, by 0920, he had completed four flights. He made no further flights during the day until about 2000 hours when he commenced the first of two flights required to spray a tomato crop. He had previously sprayed this crop on some four occasions during the previous two months. The weather was fine and warm, the wind was calm, there was no cloud and the end of daylight was at 2109 hours.

The pilot was visiting Karratha on business in his twin engined aircraft and he agreed to a request to take a friend and another local resident for a flight in the Karratha area. The three men met at Karratha aerodrome and at about 0945 hours, before proceeding to the aircraft, the pilot advised the Flight Service Officer on duty at Karratha that he would be making a local flight. Written details are not required for such flights and none were submitted. The pilot also advised that he did not require a radio watch to be kept on the «;ht for search and rescue purposes. At 0958 hours the pilot reported to the Karratha Flight Service Unit by radio that the aircraft was taxying for a local flight and that Runway 08 would be used for take-off. There was no further communication with the aircraft.

At 1125 hours Central Standard Time on 3 March, 1975 a Beech D55 'Baron' aircraft, registered VH-TYM struck the ground during an attempted 'go-around' from a landing approach at Parafield Airport, South Australia. The aircraft was virtually destroyed by impact forces and subsequent fire and the five occupants were killed.

A detailed examination of the wreckage disclosed no evidence of any pre-existing defect or malfunction of the aircraft which may have contributed to the accident.

The glider turned to the right and the angle of bank continued to increase until the wings were near vertical. The nose dropped rapidly and the glider assumed a nose down inverted attitude. As it dived towards the ground the attitude changed and the glider finally assumed a steep nose down Inverted attitude until it struck the ground.

The cause of the accident was that the pilot did not maintain an adequate margin of airspeed in the conditions that prevailed.

The pilot lost control of the glider during a turn and recovery could not be effected in the height available. The probable cause of the loss of control was that buffet, induced by aileron flutter, masked the pre-stall buffet which normally provides stall warning.

On its return to the mustering area, communication was established with a stockman riding a motor cycle who was directed towards some straggling sheep. The aircraft then dived to a low height to indicate the position of the stragglers.

An impact noise was heard shortly afterwards. Examination of the wreckage indicated that the aircraft had struck the ground in a very steep nose down attitude consistent with an uncompleted recovery from a stall. There was no evidence of any engine defect and it was established that aircraft had adequate- fuel.

On its return to the mustering area, communication was established with a stockman riding a motor cycle who was directed towards some straggling sheep. The aircraft then dived to a low height to indicate the position of the stragglers. As the aircraft pulled up from the dive the pilot said that he had lost sight of the sheep and would dive towards their position again. The aircraft again dived to a low height and climbed away with the wings level. As it commenced to level out at a height estimated as between 300 and 500 feet, the engine noise was heard to cease and it then passed out of the stockman's sight behind a tree. An impact noise was heard shortly afterwards. Examination of the wreckage Indicated that the aircraft had struck the ground in a very steep nose down attitude consistent with an uncompleted recovery from a stall. There was no evidence of any engine defect and it was established that aircraft had adequate- fuel.

After a short local flight the aircraft returned to the landing area and made a low run, at a height estimated as between 30 and 100 feet, in a south-easterly direction and passed near the group of persons on the ground. This was followed by a run at a similar height in a north-westerly direction and a further similar run to the south-east. Shortly after passing near the group of spectators on the third run, a steep climb was commenced and, at the top of the climb, the left wing dropped until the aircraft was almost inverted, the nose lowered and the aircraft rotated to the left as it dived towards the ground. The rotation appeared to cease just before the aircraft struck the ground in a steep nose down attitude and burst into flames.