The pilot was carrying out local gliding in the Bond Springs area attempting to achieve a flight time of five hours which would qualify him for a Silver C certificate. He had flown away from the vicinity of the airfield in search of lift. On returning to the airfield he became aware that he would be unable to reach the airfield and selected the only suitable area to carry out a landing. The aircraft failed to make the selected area and struck a tree during the approach, subsequently impacting the ground on the right wing and slewing through 180 degrees before coming to rest.

The balloon was landing in a suitable paddock at the completion of a 50 minute charter flight. During this time the wind strength had increased from 5-8 kt to 8-12 kt, and at touch down the basket tipped over on its side, which is normal under these conditions as the balloon deflates. However the length of drag across the ground was longer than anticipated, and the balloon did not stop until the envelope contacted a tree in its path, becoming entangled in the branches which caused damage to the envelope material. Long grass in the paddock, providing less friction than normal against the side of the basket, combined with a wind gust, have been assessed as the reasons for the extended drag on landing.

While conducting a cross-country flight, the pilot encountered deteriorating lift conditions, and an outlanding became necessary. The pilot reported that while he was on short final approach to the selected paddock he encountered strong lift, which caused him to overshoot the target touchdown point. During manoeuvring for another approach, the glider stalled and struck the ground in a very steep nosedown attitude. When it was apparent that the aircraft would overshoot the target touchdown point, the pilot had carried out a steep turn to re-position for final approach. During this manoeuvre the spoilers, flaps and landing gear had been left extended. The pilot had evidently not monitored the airspeed and the glider had stalled and probably entered an incipient spin. There had been no requirement for the steep turn to be undertaken, as a landing straight ahead was available.

The pilot reported that the three gear position indicator lights were green as he commenced the take-off roll. At about 40 knots the gear commenced to retract and the aircraft slid to a halt with all wheels retracted and the position lights indicating that the gear was up and locked. No fault was subsequently found with the landing gear system which might have contributed to the accident. The pilot had not checked the position of the gear selector lever during his pre-flight and pre-start checks. The sequence of events during the attempted take-off was consistent with the selector being in the up position. The gear system includes an anti-retraction valve which prevents inadvertent retraction while the weight of the aircraft is on the mainwheels. When the aircraft had reached about 40 knots, there was evidently sufficient lift being developed to allow the anti-retraction valve to close and the gear to retract.

During the take-off roll the aircraft did not achieve flying speed by the point where it was normally expected to become airborne. The pilot abandoned the take-off and applied maximum braking, but was unable to prevent the aircraft over-running the strip. The aircraft broke through the boundary fence and came to rest in a small ditch. The reason the aircraft did not achieve flying speed could not be positively determined. In this aircraft type, it is important that the elevator trim is correctly set for take-off. If nose-down trim is inadvertently applied, excessive rearward pressure is required on the control column in order to raise the nose. However, the trim position set by the pilot was not established. When the take-off attempt was abandoned, there was probably sufficient strip remaining to stop the aircraft. However, the brake linings and discs were worn to the extent where full brake effectiveness could not be obtained.

As the aircraft approached Jandakot Airport the pilot noticed an un-commanded increase in propeller rpm which he was unable to correct with the propeller control lever. The pilot retarded the throttle and as a result regained some control over the propeller. Shortly after the pilot reduced power the engine began to make unusual noises and the cockpit filled with smoke. The pilot decided to make an emergency landing on the only clear area available, a disused rubbish dump. The engine failed completely during the approach to land. On touch down the aircraft collided with a mound of earth and overturned. The No.6 cylinder and piston exhibited signs of severe detonation probably caused by an unserviceable spark plug. The detonation had burnt a hole through the piston and this allowed all of the engine oil to be either burnt or pumped overboard from the now pressurised crankcase. The loss of engine oil caused the propeller to move to the fine pitch stops (propeller overspeed) and eventually resulted in a complete engine failure. The pilot reported that, up until the time he observed the unexpected increase in propeller rpm, there were no indications that the engine was anything but serviceable.

Circumstances:

The pilot reported that the helicopter was taken off into the hover above the helideck, where power and performance checks were carried out. A left pedal turn at the hover was then initiated over the helideck markings to position the helicopter for take-off into a 10-15 knot wind. On completion of the turn a loud bang was heard, and a vibration felt. The helicopter was landed on the helideck, shutdown and passengers disembarked. The tail rotor had struck a communications receiver dish antenna located outside the helideck area. An inspection of the helicopter failed to reveal any pre-existing faults which may have prevented the pilot from holding the helicopter in a steady hover during the turn. This accident was not the subject of an on-scene investigation.

The pilot had been spraying a wheat crop for about 30 minutes. He advised that difficulties were encountered with the stabilisation of the spray pressure. While attempting to adjust the pressure control he temporarily forgot the proximity of three high voltage power lines which crossed the crop. The aircraft collided with these lines and pitched down steeply to the ground. Fire broke out on impact and engulfed the wreckage.

During spraying operations the engine began to run very roughly and lost a considerable amount of power. The pilot considered that insufficient power remained to permit him to divert to a suitable landing area and he attempted to land straight ahead. Towards the end of the landing roll the aircraft struck a contour bank and the right landing gear collapsed. The cause of the power loss could not be positively identified, but was probably related to excessive spark plug fouling.

The pilot was participating in a 500 kilometres cross country gliding competition. Atmospheric conditions were not favourable for prolonged soaring flight, and none of the other participants was able to cover any significant distance. However, this particular aircraft departed on the planned track, and the next reported sighting was about 3 kilometres from the accident site. At this time the aircraft was circling at approximately 300 feet above the ground and tracking to the north-west. No further sightings were reported, and the wreckage of the aircraft was subsequently discovered in a paddock 102 kilometres from the DEPARTURE aerodrome, on the intended track. Investigation revealed that the glider had initially contacted the ground with the leading edge of the right wing, while the aircraft was in a steep nose-down attitude and spinning to the right. There were no known witnesses to the accident, and it could not be established whether the pilot had been attempting to outland or to find a thermal at low level. There was no evidence of any pre-existing mechanical defect which might have contributed to this occurrence. It was probable that control of the glider was lost during a manoeuvre at low speed and height above the ground, however the reason for the loss of control was not determined.