The pilot reported that just after touchdown he felt a bump. As the aircraft slowed the nose of the aircraft sank slightly, allowing the propeller to strike the strip surface several times. An inspection of the aircraft revealed that a wallaby had struck and bent the nosegear strut. This accident was not the subject of an on-site investigation.

The pilot was conducting a flight under Night Visual Flight Rules from his property to Broken Hill. About 30 minutes after DEPARTURE the pilot reported that the aircraft engine was running roughly. Shortly afterwards he reported that the engine cowling had become detached and then that the aircraft was on fire. No further transmissions were received from the aircraft which was destroyed as a result of impact forces and fire. It was established that the No.3 cylinder became detached from the engine crankcase and damaged the engine cowling as it was forced outwards against it. The cowling blew back against, and smashed the left windshield. Engine oil escaped from the crankcase where the cylinder had been attached, and was blown onto the cabin area. The likely source of the fire was fuel escaping from broken fuel lines. Engineering investigation revealed that the lower front, half-inch cylinder hold-down nut ceased to maintain tension on the hold-down plate. Other cylinder hold-down nuts from this engine were examined and showed no signs of structural weaknesses. It is considered that the subject nut also complied to specifications, although this nut was not recovered. The engine had been overhauled 46 flight hours prior to the accident. It is considered that the nut was incorrectly torqued at that overhaul. The reason for the incorrect torquing of the cylinder hold-down nut could not be established. The subsequent severe impact with the ground was a result of the extreme distractions with which the pilot had to contend. The aircraft was cruising at 3500' AMSL when the engine disintegrated and the fire broke out. Part of the emergency procedure for this type of occurrence is to dive the aircraft in an attempt to blow out the fire. As the aircraft impacted the ground in a steep nose-down but wings near-level attitude, and only slightly off course, it is thought that the pilot was complying with that drill. However, the low cruising altitude did not afford him sufficient time to accomplish this and establish the aircraft in a more suitable attitude for a forced landing. His limited night flying experience in combination with a dark night might have resulted in him not being able to estimate his height above ground level.

The pilot reported that shortly after the aircraft became airborne, he noted a substantial change in propeller pitch noise and an associated loss of performance. Insufficient runway remained to permit a landing straight ahead. The pilot raised the landing gear and flap, however the aircraft failed to climb and the airspeed decayed to below the safe single engine speed. The take-off attempt was abandoned and a forced landing was carried out off the end of the runway. The rear fuselage impacted heavily on a dirt bank 78 metres beyond the runway threshold, following which the aircraft passed through a fence and slid for a further 78 metres before coming to rest. No fault was subsequently found with the engines or systems of the aircraft which might have explained the reported loss of performance. Calculations indicated that the weight of the aircraft at the time of take-off was close to the maximum allowable, but the centre of gravity was aft of the rear limit. Several of the passengers indicated that the aircraft rotated sharply to an unusually high nose attitude as it became airborne. The pilot's action in raising the flap when he perceived the power loss was contrary to the emergency procedures for the type, and probably resulted in sink and a further reduction in airspeed.

While the aircraft was cruising at 2000 feet above mean sea level the engine commenced to run roughly. Trouble checks failed to determine the source of rough running and the pilot elected to land at an enroute aerodrome. However before reaching this strip, the engine lost power completely and the pilot was committed to a forced landing. Because of crowds at an adjacent beach, the pilot attempted to land on a road. Touchdown was further along the road than expected because of a strong tailwind component, and the aircraft collided with a kerb before coming to rest. Investigation revealed that nuts on the various bolts and studs securing the number 3 cylinder to the crankcase had evidently not been correctly tightened. Five of the eight mounting studs/bolts had failed from fatigue during normal operations, finally allowing the cylinder to become loose. The engine had completed 83 hours time in service since an overhaul. There was no logbook record to show whether the particular cylinder had been removed or replaced since that overhaul.

The pilot was conducting a flight to check the output of the spray system fitted to the aircraft. During the take-off he heard a noise from the rear of the aircraft and noticed something moving away from the aircraft. He continued with the take-off and two spray runs before positioning the aircraft on a downwind leg for landing. As the aircraft was turned onto the base leg the pilot realised that he could not apply left rudder. The pilot stated that he then intended landing the aircraft on the base leg but found that cone markers blocked the path. The aircraft was then lined up with and landed on runway 22. An inspection determined that the leaf-spring mounting that retains the tailwheel had failed due to fatigue. The loss of rudder control experienced by the pilot resulted from the bending of the left rudder to tailwheel control arm so that adequate left rudder could not be applied. It is considered that the leaf-spring failure should have been detected during routine maintenance or pre-flight inspection.

At the end of each spray run to the east, the aircraft was flown under a power line before the turn to change direction was commenced. Several runs had been completed when the pilot climbed the aircraft to commence the turn and the aircraft collided with the power line. The pilot dumped the remainder of the load and the aircraft continued to fly, trailing the power line. After travelling a short distance the aircraft apparently stalled and struck the ground in a nose down attitude. A fire broke out and completely engulfed the wreckage. The pilot subsequently advised that he had temporarily overlooked the presence of the power line. It was probable that on this particular spray run a pole supporting the wire was no longer in the pilot's field of vision. The severed wire became entangled around the right wing and lift strut, resulting in bending of the strut and probably inducing stalling of the wing.

The purpose of the flight was to deliver the aircraft to its new owner. The aircraft had been imported from Papua New Guinea in December 1985 and had flown only a limited amount since that time. The pilot carried out three circuits prior to departure, and made a successful landing enroute for refuelling. However, on touchdown at Bankstown following a normal approach, the nosegear collapsed. Initial investigation revealed that the nosegear downlock had not completed its travel to the overcentre position. In addition, the microswitch was incorrectly adjusted, giving a down and locked indication before the lock was fully engaged. The nosegear had collapsed because of faulty rigging of the gear, which prevented it from completing the full extension cycle. The applied loads had been held by the actuating rods and bellcranks until a bellcrank rod end had failed in overload.

The pilot was carrying out a pre-flight inspection of the aircraft in preparation for an Instrument Rating flight test. He had selected the flaps down, and began operating the hydraulic hand pump to extend the flaps. After a few pump cycles, the right maingear collapsed and the pilot then noted that the gear selector was in the up position. It was suspected that the anti-retraction valve, which is designed to prevent gear retraction on the ground, was unserviceable. However, no fault was discovered. Tests determined that the gear could be unlocked if the hand pump was operated rapidly, and the pilot advised that he had pumped briskly on this occasion. The check list provided by the aircraft operator did not alert pilots to confirm the position of the gear handle before using the hydraulic hand pump. It was not possible to establish why or by whom the gear selector had been placed in the up position.

The pilot had hired the aircraft to fly to Piper's Field with three friends for the day. He was familiar with the strip which is used for glider operations. On arrival in the circuit area, the pilot contacted the local gliding club by radio and was advised that gliders were landing and taking off in a southerly direction. The strip, 686 metres in length, has a one percent average down slope to the south. The wind velocity was reported as 200 degrees at 10 knots. The pilot reported that the aircraft encountered sink on final approach and that he applied power to counteract the sink. The aircraft touched down well into the strip and bounced. The second touchdown was about halfway along the strip and the pilot was unable to stop the aircraft before it overran the strip. The aircraft was damaged when it ran through a ditch which was concealed by long grass.

While the aircraft was being turned left to line up on a runway situated on a black soil plain, the right mainwheel broke through the runway surface, dropped into a concealed hole beneath the crust and bounced out again. The pilot shut down the engines and after inspecting the aircraft elected to fly it to Alice Springs. On arrival the aircraft was placed unserviceable. An inspection by an engineer revealed that the right maingear had been displaced rearward, the gear support structure buckled and the right engine was found to droop 1.5 centimetres.