Collision with terrain

The pilot was engaged in a muster of cattle for a brucellosis test. He was chasing a calf that had broken away from the main herd. When the animal turned towards the helicopter, the pilot attempted to take evasive action. He felt the aircraft rock, and believing that it had been struck by the animal, pulled it up to about 40 feet above the ground. The aircraft began to yaw. During the subsequent landing, while still yawing, the landing skids collapsed. The investigation revealed that the animal had not contacted the aircraft. During the evasive action taken by the pilot the tail rotor had contacted the ground which resulted in the loss of directional control. This accident was not the subject of an on-site investigation.

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 pilot was attempting to take-off at night from an unlit runway, using the headlights of a car positioned at the upwind threshold for guidance. After becoming airborne the aircraft failed to climb away normally and collided with the car, killing one of the occupants. Although the aircraft had sustained substantial damage it remained airborne, and a safe landing was carried out at the planned destination. It was calculated that the aircraft was travelling at an approximate airspeed of 105 kt when it struck the car. No fault was found with the aircraft that would have prevented it from climbing normally after lift off. The reason the aircraft failed to climb could not be determined.

The aircraft was engaged in the aerial spotting of sheep and relaying the information by radio to ground mustering parties. When the muster was completed in that area, the aircraft was abserved to climb away, but the pilot's intentions were unknown. The aircraft was not seen again that day and when it had not returned by night a search was commenced. The wreckage was located the following morning near the site where the aircraft had last been observed. The aircraft had struck the ground in a nose low, right wing low attitude with no apparent forward speed. No fault was found with the aircraft that could have contributed to the accident. It is probable that while operating at a low altitude the aircraft had stalled and that the pilot had been unable to effect a recovery in the height available.

The pilot reported that while cattle-spotting at about 200 feet above ground level the engine lost power. He commenced a forced landing into a large clearing when, at about 30 feet, the engine regained power. He reported that he attempted to fly away but the aircraft sank, nose-down and left wing low, to the ground. Examination of the engine found no explanation for the reported loss of power. The left wingtip had scraped the ground for a distance of 28 metres, with the aircraft banked at an angle of approximately 45 degrees. The aircraft had then yawed left and cartwheeled for 65 metres before coming to rest. Damage to the propeller was consistent with the engine producing high power.

On the evening preceding the accident the pilot indicated his intention to commence mustering early the next morning. The pilot arose at about 0530 hours and it is believed that the aircraft took off at about 0600. The aircraft was seen at about 0620 by the stockmen. It was flying at about 100 ft agl and when the engine noise ceased and the aircraft was not seen again one stockman rode to a nearby bore and found the inverted aircraft wreckage. The aircraft had impacted the ground in a near vertical attitude. No contributory fault could be found with the aircraft or the associated systems. The pilot did not hold a mustering approval and no evidence of him having undergone such training could be found. It is probable that the aircraft stalled at low level and that the pilot was unable to regain control before ground impact.

Circumstances:

A weather front was approaching Rottnest Island from the north-west. The pilot departed before the weather arrived, climbing to 1500 feet whilst intercepting the south easterly track to Jandakot. Shortly after reaching 1500 feet, the weather closed in, and the pilot was unable to avoid entering cloud. The pilot did not request assistance from Perth Air Traffic Services. Instead, he turned towards the island and commenced an instrument descent expecting to descend clear of the cloud and land at Rottnest without difficulty. The aircraft exited the cloud at a low height above the sea, to be suddenly confronted with boats and land. During the sharp left hand avoidance turn, the left wing struck the water. The aileron was torn off and the wing and fuselage were damaged by the impact. The pilot retained control and carried out an emergency landing at Rottnest Island airport.

The weather was fine when the pilot departed Bankstown, however, deteriorating conditions were encountered enroute. Communication was lost with the aircraft after the pilot reported he was holding at a point some 15 kilometres from his destination. Searchers subsequently discovered the wreckage of the aircraft in water, 900 metres from the intended landing strip. No fault was found with the aircraft that would have been likely to contribute to the accident. Thunderstorms, low cloud and extremely heavy rain were present in the area. It is probable that the pilot was manoeuvring the aircraft for a landing when it struck the water.

The flight was to be a period of solo practice exercises following the completion of a Commercial Licence flight test a number of weeks earlier. The pilot conducted a number of circuits and landings, and on this circuit was carrying out a power termination autorotation landing from 800 feet above the ground. As he commenced levelling the helicopter from the flare, he felt a bump at the tail. He landed the helicopter and shut the engine down. An inspection revealed that the tail rotor had contacted the ground, severing the tail rotor blades. The resultant vibration and imbalance caused the tail boom to fracture and the horizontal stabiliser to became detached. No pre-existing defect was found with the helicopter which could have contributed to the occurrence. It was evident that the pilot had misjudged his height above the ground during the landing flare.

During the flight the pilot encountered gradually deteriorating weather conditions, forcing him to reduce his cruising altitude from 5500 feet initially, to below 3500 feet. Cloud covered the tops of the adjacent ranges and there were showers and associated low cloud in the accident area. The aircraft struck the ground at 2140 feet amsl, while flying level, banked 20 degrees right, under control and on a heading 80 degrees to the right of the flight planned track. Shortly before the accident occurred the aircraft entered an extensive area of hill fog whilst being flown at low level and at cruising speed. The pilot was probably attempting to turn back when the aircraft collided with trees on higher ground than a valley he had just overflown.