The pilot was approaching to land in what he believed were light wind conditions. As he crossed the threshold he realised that there was a tailwind component, but elected to continue the approach. Touchdown occurred with about 415 metres of the strip remaining. During the landing roll the pilot became concerned that the aircraft would not stop before the boundary fence, and a ground loop was attempted. The left maingear collapsed as the aircraft came to rest 103 metres from the end of the runway. The landing attempt had been made in 12 to 15 knot downwind conditions. The pilot had assessed the wind direction from the smoke emitted by nearby power stations. He had not noticed the direction indicated by the two windsocks at the aerodrome. It was likely that the pilot was mentally fatigued following a long and difficult day at his workplace, and he may have been pre-occupied with business matters which were related to the reason for the particular flight.

The pilot held a Student Licence as issued by the AUF. During a landing approach the aircraft overshot the intended touchdown point. It subsequently ran off the end of the strip and collided with a tree. It was reported that the student was not being supervised by an instructor at the time of the accident. The reason he apparently misjudged the approach was not determined.

Prior to DEPARTURE, the pilot had been made aware of a Notam advising pilots to disregard temporary displaced threshold markings for runway 27 at the destination. During the subsequent approach the pilot noticed red and white lighting, and associated this with the displaced threshold. It was his intention to land beyond these lights, which were in fact the runway approach lights. Very late in the approach the pilot realised he was too low, but before power could be applied the aircraft struck the lights, 180 metres short of the runway. The maingear legs were torn off and the nosegear collapsed before the aircraft slid to a halt on the side of the runway. The pilot had been confused by the Notam relating to the displaced threshold, but had not sought clarification prior to DEPARTURE. He had limited night flying experience and was unfamiliar with the presentation of High Intensity Approach Lighting. It was evident that during the approach he had focussed his attention on these lights, to the exclusion of the runway lighting.

The pilot had conducted a soaring flight for an hour in particularly turbulent conditions. The subsequent landing was conducted with a light crosswind from the right. The pilot misjudged the flare, and the aircraft ballooned to a height of about 15 feet, while veering to the left. The pilot then retracted the air brakes and the glider subsequently struck the ground heavily in a slight nosedown attitude. This had been the longest flight undertaken by the pilot, and the weather conditions probably resulted in stress and fatigue. The landing flare had been made with rapid, rather than progressive, control movements. The pilot had then lost directional control, and while he was attempting to regain a normal glide attitude the aircraft had struck the ground in a shallow dive.

The pilot was operating from a strip on top of a ridge line. Because of the slope of the strip, landings were being made with a quartering tailwind of about 10 to 15 knots. At the end of a landing roll, the pilot commenced to turn around prior to reloading, when the wind gusted to about 25 knots. The pilot applied more power in order to assist the turn, but the nosewheel bounced into the air. The aircraft weathercocked and ran off the side of the strip. It then ran down the slope of the ridge line until the nosewheel entered a large hole and the aircraft overturned. The pilot attempted to turn the aircraft around for reloading while traversing an area of rough ground adjacent to a steep slope at the side of the strip. All previous turns to position for reloading had been conducted on a flat area on the opposite side of the strip. However, the pilot decided to reverse the direction of turn to assist the loader driver who was experiencing difficulty in positioning the loader close to the aircraft.

The task of spraying a cotton crop was nearing completion. The time for a scheduled radio call was approaching, and on checking his watch the pilot found a need to alter its setting. He also checked the amount of spray liquid remaining in the hopper. As a result of these distractions, he momentarily relaxed his vigilance in regard to a powerline obstruction located at the end of the spray run. As he approached the powerline he took action to gain altitude, but the main landing gear struck the wires causing the aircraft to land heavily in an adjacent paddock.

Shortly after take-off the pilot noticed a 10 to 15 centimetre gap between the forward ends of the upper and lower cowlings on the left engine. He elected to continue the flight at reduced airspeed and engine power. About 15 kilometres from the destination the upper cowling became detached and struck the horizontal stabiliser. It remained wrapped around the stabiliser and resulted in severe vibration and a temporary loss of elevator control. The pilot was able to regain control, and during the turn onto a long final approach elevator control returned to normal when the engine cowling fell free. The cowling did not become detached until well after DEPARTURE. It was likely that an uneventful landing could have been carried out had the pilot returned to the DEPARTURE aerodrome as soon as he noticed the problem. The detached cowling was not found and the reason for the failure of the latches to hold it in place was not determined. However, the surface of the DEPARTURE strip was reported as rough and the aircraft had flown about 12 hours since the cowlings were last disturbed.

After an apparently normal approach the Captain and First Officer reported a firmer landing than expected. Towards the latter part of the landing roll the crew noticed that the aircraft had a slight list to the left. While the aircraft was being turned off the runway the "left wing door open" warning light illuminated. This was followed by an indication of a reduction in the hydraulic fluid quantity in the number 4 system. The appropriate check list was completed and the aircraft was taxied to the terminal. As the aircraft approached its designated parking position the engineering ground crew noticed that a section of the left wing landing gear was protruding through the upper surface of the wing. The aircraft was immediately shut down and all the occupants disembarked. Inspection of the aircraft found that the rear section of the landing gear trunnion in the left wing had failed. A metallurgical examination of the trunnion determined that the fracture was caused by the growth of a stress corrosion crack, which was followed by the growth of an unstable ductile crack. The aircraft manufacturer issued a service bulletin, several years previously, to cover the possibility of cracking in the trunnion caused by corrosion. The work required by the service bulletin had only been partially completed on this aircraft at the time of the accident.

The pilot was a Chinese citizen who was being trained, as part of an Australian Development Aid program, to a standard equivalent to that required for an Agricultural rating. His Chinese Commercial Licence was suitably endorsed to allow training in this country. The flight in question was authorised as a practice spraying exercise and was to be the pilot's last solo sequence before a flight test. At the end of the first practice spraying run the entry into the procedure turn was delayed, and the turn was then conducted at less than the normal angle of bank. This placed the aircraft in a wide and low turn, during which it collided with a tree. This collision occurred at about 50 feet above ground level, and the aircraft struck the ground 35 metres beyond the tree. The pilot subsequently reported that the aircraft had been affected by a downdraft. However, other pilots and ground witnesses in the area indicated that excessive sink or downdrafts were unlikely to have occurred. The tree struck was prominent and contrasted well with the surrounding vegetation. It was likely that the pilot was looking back to check his flight path in relation to the spraying runs and had not seen the tree prior to the collision.

The pilot, who is an approved AUF instructor, was conducting a solo test flight, following complaints by a student that directional control was more difficult than normal. During the takeoff run a rudder lever arm collapsed, directional control was lost, and the aircraft collided with a fence. It was likely that the directional control problems originally reported were related to the rudder lever arm being bent. The reason for the bending was not established, but the lever had evidently been weakened to the point where it failed during the attempted takeoff.