The pilot was making a landing approach, to an area not normally used for helicopter operations, at the conclusion of a stock mustering operation. The helicopter collided with a single wire telephone line then landed heavily, rolling onto its side as the skids collapsed. The pilot reported that the wire was normally difficult to see because of age discolouration and the long span between poles. On this occasion he had forgotten that the wire ran through the area and did not see it during the approach. This accident was not the subject of an on-site investigation.

The pilot had intended to carry out aerobatic practice in the Dry Creek Aerobatic Training Area. After DEPARTURE, the pilot requested, and was cleared to operate in the Dry Creek area up to an altitude of 3500 feet. The aircraft was then observed to be spinning and crashed into a salt evaporation pan. The investigation revealed no pre-existing defects with the aircraft or its systems which may have contributed to the pilots inability to effect recovery from the spin. However, it was found that, at the time of the accident, the weight of the aircraft exceeded the maximum allowable by about 26 kilograms. The pilot was a member of a local aerobatic club and had accumulated some 30 hours of aerobatic flight. He had been assessed by his instructors and other experienced club members as a competent aerobatic pilot. The circumstances surrounding the entry to the spin and reasons for the pilots apparent inability to recover from the manoeuvre could not be determined.

The pilot had flown to Whirly Hole the previous day and after helping with the muster, the aircraft was landed and left overnight on the strip. Next morning, when the pilot attempted to start the engine, he found that he had left the master-switch in the ON position, which flattened the battery. He attempted to hand start the engine but it failed to fire, so after re-priming he set the throttle to a position which equates to about 1200 RPM. Upon the second start attempt, the engine fired but the aircraft moved off at a reasonable speed, with the pilot unable to intercept it before it struck a tree. Prior to starting the engine, although the pilot checked the park brake lever was still in the ON position, he did not re-apply pressure to the brake pedals. It is probable that hydraulic pressure bled off during the night or that the brakes were only lightly applied the previous evening. The brake system was serviceable and the pre-start checks include a requirement to test and set the brakes.

The taxiway for the particular strip is a continuation of the gravel centre section of the strip. The taxiway then makes a right angled turn. After a normal landing the pilot proceeded straight ahead, along the taxiway but failed to negotiate the turn. The aircraft entered a ditch and the left wing struck the ground. No fault was found with the aircraft's brake or steering systems that could have contributed to the accident. Insufficient attention was paid to the operation of the aircraft and the turn was attempted at too high a speed.

On the previous day the pilot had ferried the aircraft to a maintenance organisation for a scheduled servicing. No abnormalities were discovered and a satisfactory engine run was carried out by the pilot prior to DEPARTURE for the return flight. A search was commenced when the helicopter did not arrive at the destination, and the wreckage of the aircraft was located after a VSB signal was heard. The aircraft was lodged in the branches of a tree some 18 metres above ground level. The tail boom was lying near the base of the tree and most components had received substantial impact damage. Examination of the wreckage revealed that the engine had failed during flight. This was caused by a fatigue failure in the number 2 cylinder connecting rod big end cap. The damaged end of the connecting rod broke away a large piece of the crankcase housing the lubricating oil gallery. This led to overheating of bearings through a lack of essential lubrication. The reason for the fatigue crack initiating could not be established because of extensive post fracture mechanical damage at the origin. The terrain over which the aircraft was flying was unsuitable for a forced landing.

The pilot was conducting a parachute drop from 9000 feet. She reported that the cloud base was broken at about 4500 feet and that she climbed the aircraft through a break in the cloud cover to reach the drop altitude. After the parachutist had exited the aircraft the pilot found a break in the cloud cover and descended. However, she was then unable to locate the airstrip and spent some time flying in various directions until she decided to land and ascertain her location. A paddock was selected and after an aerial inspection a landing approach was conducted. The aircraft touched down about 150 metres into the paddock in tailwind conditions. It then ran through a fence, across a road and struck another fence before the nosegear leg collapsed. The aircraft then nosed over and came to rest inverted. The accident site is located about 47 kilometres south-west of the Hillman Farm Airstrip. After descending below the cloud base the pilot's reported actions did not include basic procedures when lost. She advised that when she could not establish her position, she became confused and apprehensive and consequently picked an unsuitably short paddock in which to land. The pilot had only recently recommenced flying after a 3 year break, and had completed a biennial flight review prior to conducting these parachute drops. Although this review totalled almost 6 hours flying and covered many important sequences, the instructor did not appreciate that the pilot had no cross-country experience in at-least that time. Navigation techniques and basic actions if lost were not covered in the review.

About five minutes after take-off, the pilot heard a change in engine note and felt a slight yaw to the left. This occurred several times in quick succession. The pilot reduced power and commenced a descent towards a disused mining area. At about 200 feet agl, the engine failed and an autorotational descent was set up. As the pilot was attempting to manoeuvre the helicopter into wind and clear of some mullock heaps, the helicopter touched down heavily on the rear of the landing skids and the tail rotor struck the ground. The main rotor then severed the tail boom and the helicopter came to rest ten metres from the initial point of impact. The engine oil cooler supply line was too short for its length of run and was routed past a stud on one of the magnetos. The stud abraded the line to the point where it caused it to leak and the loss of oil resulted in the engine seizing.

The pilot was approaching to land on a one-way agricultural strip. He was aware that the owner of the strip had placed a fence across the approach end, but was not aware that there was a second fence some 15 metres in from the first. This fence was not easy to see from the air. The aircraft cleared the first fence, but collided with the second. The pilot had walked part-way along the strip to inspect its condition prior to his landing attempt, but did not detect that there were two fences at the approach end. The pilot's aiming point was very close to the approach end boundary.

The pilot had been conducting a series of circuits with touch and go landings. Shortly after take-off for another circuit, the engine lost power. The pilot pumped the throttle and the engine responded briefly, but then failed again. The pilot was committed to a forced landing in an unsuitable area. The touchdown was heavy, the nosegear was dislodged, and the aircraft overturned. The reason for the loss of engine power was not established.

The pilot stated that he carried out a normal circuit at his destination. During the landing roll he selected the flaps up, and then inadvertently selected the landing gear up before realising his mistake and selecting the gear down again. The gear up selection occurred just as the aircraft was travelling over a hump in the strip and it is believed that this, combined with the pilot holding up elevator, caused the weight of the aircraft to come off the wheels. This resulted in the landing gear safety switch becoming ineffective and the gear commencing the retraction sequence. When the aircraft came to rest the nosegear was fully retracted, the left maingear was partially retracted and the right maingear was still down and locked. Subsequent inspection and testing of the landing gear system did not reveal any faults that could have contributed to the occurrence. The pilot stated that he believed he had mistakenly applied the after-takeoff checks instead of the after-landing checks and had selected the gear up instead of opening the cowl flaps. This accident was not the subject of an on-site investigation.