As part of a refresher check on the aircraft, the instructor required the pilot to use the manual system for lowering the landing gear. After turning the crank handle the recommended number of turns the gear down light did not illuminate. The pilot continued to rotate the crank handle a few more turns and a loud bang was heard, following which there was little resistance to crank handle movement. However, the gear down light still did not illuminate although the visual gear position indicator in the cockpit did indicate that the gear was in the down position. The gear actuator circuit breaker was reset and the gear selected up; the gear did not retract but the gear unsafe light illuminated. All further attempts to obtain a gear down light were unsuccessful. Observations made from another aircraft and by persons on the ground indicated that the gear was down and locked. The aircraft was diverted to Bankstown and the gear collapsed immediately after touchdown. A fault in the gear indicating system prevented illumination of the gear down light when the gear reached the down and locked position on the initial manual extension. When the crank handle was wound further, an overload failure of the actuator housing occurred. The gear was unlocked when the up selection was made but the damaged actuator prevented either retraction or safe extension. The actuator has a vital function in retaining the gear in the down and locked position as it pre-loads the landing gear braces in an overcentre position. Once the actuator was damaged, gear collapse on landing was inevitable.

The pilot was engaged in mustering cattle out of thick undergrowth. As he was moving the helicopter slowly forward, while checking the undergrowth for any remaining cattle, the main rotor moved under the overhanging branch of a large tree. The pilot attempted to move the helicopter down and to the right but the main rotor struck the overhanging branch. The helicopter impacted the ground and caught fire. The tree trunk was camouflaged by rubber vine, which constituted much of the undergrowth and probably reduced the pilot's awareness of the proximity of the tree.

The pilot stated that the aircraft was caught in a downdraught just prior to touchdown. The aircraft landed heavily and bounced. After a second bounce the pilot carried out a go-around. Following the subsequent landing, the damage to the propeller, fuselage and engine firewall was discovered. The landing was made on strip 04 and meteorological analysis indicates that at the time the wind was probably a south-easterly at 10-15 knots. It is likely that improper compensation for the wind conditions and an improper landing flare were causal factors in the accident. This accident was not the subject of an on-site investigation.

Whilst mustering cattle near a holding yard, the helicopter was being held in the hover in a 15-20 knot headwind. Because some of the cattle broke away, the pilot turned downwind to herd them back. As the aircraft rolled out of the turn it began to descend and the pilot attempted to arrest the sink by increasing collective. However, the helicopter continued downward and impacted heavily on the ground resulting in the tail boom being sheared off. It then bounced into the air and began to yaw rapidly but the pilot quickly and firmly placed it back onto the ground. When the helicopter came to rest the occupants were able to extricate themselves from the wreckage. The pilot misjudged the performance that could be expected from the helicopter. When the machine was turned downwind, the sudden loss of lift resulted in a descent from which the pilot was unable to recover before the aircraft collided with the ground. The pilot reported that he believes he overpitched the main rotor during the recovery attempt.

Shortly after what was reported by the pilot as a normal landing the nosewheel fork failed. This allowed the nosegear strut to dig into the strip surface and resulted in the aircraft overturning. The nosewheel fork failure was found to have been caused by overload forces and there was no evidence of any pre-existing defect.

After application of full throttle during the takeoff run, a severe vibration developed which rapidly stopped the engine from rotating. When the aircraft came to rest the pilot noted that one of the two propeller blades had cleanly separated from its hub. The hub failed as a result of fatigue cracking which extended around approximately half of its circumference. The cracking originated in the root of the blade retention thread and grew progressively over about 850 flights. The cracking was not visible during normal periodic inspections because the hub had been painted to help prevent corrosion.

A group of five firemen had finished a task in a fire fighting area and were to be winched out from steeply sloping terrain. The helicopter hovered at about 30 feet while the first two men attached themselves to the dual winch hook. They were then raised to the aircraft, following which the next fireman was also lifted. The remaining two men then attached themselves to the hook. The operation proceeded normally until the men were close to the skids of the helicopter. At this point the winch cable broke and the men fell to the ground. An inspection of the cable revealed that it had come off one of the pulleys of the hoist and become jammed. Fraying of the cable had occurred and it had finally failed in overload at a point some 4 metres from the hook. A number of kinks were found in the cable, possibly resulting from the operator's maintenance and inspection procedures. Such cable twisting would have increased the possibility of the cable riding over the edge of the pulley, particularly when the cable was not under tension. Such a situation would occur when extra cable was paid out to assist with the attachment of the cable to a person's lifting harness. The length of frayed cable was consistent with this sequence happening on the hoist on which the accident occurred.

Circumstances:

The aircraft was cruising at 2500 feet above ground level when the engine suddenly stopped. The pilot carried out a forced landing in heavy scrub, during which the aircraft was extensively damaged. The pilot declined to provide any information. However, other information obtained indicates that the right wing tank contained 90 litres of fuel and the left wing tank unusable fuel only. The contents of the fuel lines indicated that the engine had stopped as a result of fuel starvation. No defects were found which may have contributed to the accident.

The aircraft was the first of a group of four aircraft being used to return staff to an alluvial gold mine after a weekend break. The weather in the area of the destination was not suitable for a visual arrival and the aircraft was initially held for several minutes in an area five kilometres to the south of the strip, awaiting an improvement in the weather. The aircraft was then flown towards the strip and the pilot reported to a following aircraft that there had been a lot of rain and that the strip looked wet. He also advised that he intended to carry out a precautionary circuit and check if it was safe to land. No further transmissions were received from VH-TLQ. The wreckage of the aircraft was subsequently found burning in a river valley, 300 metres west of the threshold of runway 34. Surviving passengers stated that the aircraft struck trees shortly before impact. There were no ground witnesses. The aircraft had impacted the ground in a steep nose down left wing low attitude, at a low forward speed, then cartwheeled up rising ground before coming to rest inverted, 42 metres from the point of impact. The cabin area was destroyed by an ensuing fire. An inspection of wreckage did not reveal any mechanical defect or failure that could have contributed to the accident. The reasons for the apparent loss of control of the aircraft could not be determined.

The aircraft arrived in the circuit area in the late afternoon. The pilot assessed that the prevailing wind would make it necessary to land into the sun on Strip 29. He overflew the strip and carried out a right hand circuit intending to touch down on the left side of the strip, to allow for the crosswind. After touchdown, the pilot looked out of the left window in an attempt to keep the aircraft aligned with the strip. However, he did not see three half 200 litre steel drums that were located 14 metres in from the left side of the strip and the left mainwheel struck one of these drums. The left maingear folded and the aircraft slewed to the left and became entangled in the perimeter fence before coming to rest. The steel drums encroached on the strip landing area. The pilot was not aware of their location before landing although the drums could be readily seen from circuit altitude. The non-standard circuit pattern, the decision to land on the left side of the strip and the sunglare all contributed to the accident.