Loss of control

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.

At 1627 hours the wreckage of VH-EQU was located in an area of relatively dense timber 137 metres beyond and 91 metres to the left of the end of Runway 14 at Batchelor. The aircraft had struck the ground at a relatively low speed whilst in a steep nose down, left wing down attitude. The evidence indicates that the aircraft sustained a substantial, but unexplained, loss of power at a low height after take off.

The unmarked area being used as an agricultural airstrip was situated on a narrow ridge aligned north/south. There was high ground to the north and wide deep valleys in all other directions and it was necessary for landings to be made to the north and take-offs to the south. The strip was 365 metres long and it curved 15 degrees to the left at a point 243 metres from the southern end. It sloped down at 2.75 degrees for the first 152 metres and then rose at a 4 degree angle to the loading area which was near level. The central section was about 11 metres wide and the surface of short grass and bare earth was smooth.

The aircraft touched down at about the point where the longitudinal slope changed and in the long grass to the right of the central section. The aircraft ran parallel to the southern portion of the strip and the pilot attempted to steer it left into alignment with the northern section. Although the heading of the aircraft was changed to the left, the wheels skidded on the surface, the path of the aircraft did not change and it failed to follow the curve of the strip. As the aircraft approached a gully where the ground fell away steeply, the pilot applied full engine power in an attempt to "go around". The aircraft became airborne at low speed as the ground fell away but it then descended, struck the steeply sloping ground and overturned. It came to rest at a level about 100 feet below that of the northern end of the strip.

VH/ULC had been constructed by the pilot and was classed as an amateur-built aircraft. Being an amateur/built aircraft, a flight test schedule was required to be completed before a Certificate of Airworthiness could be granted.

The pilot flew the aircraft several times and on the day of the accident had completed a flight of approximately two hours duration. After the aircraft was refuelled to capacity the pilot made it known that he intended to carry out a further flight and after starting the engine the aircraft was seen to taxi out and takeoff from runway 03 into a 10 to 15 knot headwind. At a height of about 300 ft after takeoff, the engine noise was heard to stop suddenly and the aircraft was seen to turn towards the right. It then descended rapidly and struck the ground in a near vertical nose down attitude. Subsequent examination of the wreckage failed to reveal any evidence of a pre-existing.defect or a reason for the engine's sudden loss of power.

Aircraft bounced several times on takeoff pulled into air in stalled condition. Prop pitch found faulty.

Unauthorised flight by student pilot lost control after takeoff. The car arrived at the southern end of the airstrip as the aircraft commenced to take off towards the north. After a short ground roll, the aircraft became airborne and climbed steeply to a height of about 150 feet. It then commenced a steep climbing turn to the left and, after turning through some 90 degrees, the nose dropped and the aircraft dived to the ground and overturned after impact. Shortly after impact a fierce fire broke out and extended to the surrounding scrub.