Circumstances:

The pilot had been hired to ferry the aircraft to the operator in Western Australia and had landed to refuel at Elliot. While on the ground, he agreed to deliver a box to the Wave Hill police station and stowed it, unrestrained, on top of a jerry can in the unoccupied seat. The aircraft was reportedly fitted with permanently installed dual controls. On approach to land at Wave Hill Station, the box shifted, fell onto a swag on the floor and restricted the movement of the cyclic control. The pilot was thus unable to manoeuvre to avoid a cattle crate stand and the tail rotor struck one of the rails. The helicopter then landed heavily on its skids.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Inadequate preflight preparation - improperly stowed cargo.

2. Unrestrained cargo moved and caused restricted movement of the flying controls. This accident was not the subject of an on-scene investigation.

The pilot reported that shortly after establishing cruise at 300 feet above ground level the aircraft suddenly began to shake as if something had been thrown into the propeller. The engine stopped shortly afterward and, after establishing a glide and making a radio call, the pilot attempted to restart the engine. The engine would not turn over. A landing amongst scattered scrub and clumps of grass was made. Examination of the propeller disclosed that one blade had failed due to a large fatigue crack adjacent to the mounting holes in the blade root. The blade had then severed a bracing wire running between the wing trailing edge and the fuselage behind the propeller. The wire had become entangled in the other propeller blades. The propeller blades were constructed of fibreglass strands in a resin matrix covered with a layer of carbon fibre cloth. Visual and x-ray examination of the blades indicated that the strands were not uniform in direction in the area of the blade roots, some sections had no strands at all, and there were voids in the matrix. These faults reduced the strength of the blades in that area. All blades showed evidence of fatigue cracking near the mounting holes. The holes had been made by multiple drilling. The blade manufacturer advised that he was aware of the faults and had altered the production method. He had advised all owners of similar blades of the deficiencies. This accident was not the subject of a formal on-scene investigation.

Circumstances:

On DEPARTURE from Bankstown, the landing gear retracted normally. On selection of gear down in the circuit at Hoxton Park, the pilot could not obtain a green gear down light. He observed that the main gear appeared to be fully extended. He carried out the manual extension procedures as set out by the manufacturer but was still unable to obtain a green light. He returned to Bankstown where an inspection from the tower and engineering advice indicated that all three legs appeared down and locked, although the nose gear forward doors had not closed. The pilot made a normal landing on the mainwheels, holding the nosewheel off for a short distance, and then gently lowering it as speed reduced. Soon after contact with the runway, the nose gear collapsed. The investigation disclosed that the retractable step hinge point was rusty with no sign of lubrication, and the retract cable was found to be tight in its outer cable. The retraction cable had also formed a loop within the nosewheel well, and it was this loop which had fouled the down lock mechanism, preventing the nose gear from locking down. During retraction tests it was noted that the step remained in the retract position even with the gear down and locked. The step should normally extend and retract with the nose gear. The aircraft had a history of landing gear defects and maintenance organisations which had worked on the aircraft seemed unaware of the correct performance and operation of the retractable step. The overall standard of landing gear maintenance and lubrication was inadequate. This accident was not the subject of a formal on scene investigation.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Inadequate maintenance of the landing gear system.

2. Inadequate preflight inspection of aircraft by pilot.

Circumstances:

The pilot reported that he was making an adjustment to the fuel selector, at the top of climb, when he noticed a lower-than-expected reading on the right outboard fuel quantity gauge. Suspecting a loose fuel cap, he advised the co-pilot to carry out a visual inspection of the right wing area with a torch. Although the fuel cap appeared to be seated properly, the decision was made to return to the DEPARTURE runway and carry out a more thorough investigation. During the landing roll the right engine lost all power, and the pilot attempted several unsuccessful restarts. At the end of the runway the aircraft was turned tail into wind, and another restart was attempted. As the engine started the co-pilot observed flames under the right wing area and activated the engine fire extinguisher. The co-pilot then exited the aircraft to investigate and returned immediately to inform the pilot that the aircraft was on fire. Both engines were shut down and the pilots exited the aircraft. The investigation showed that the rubber fuel cells inside the right wing had collapsed upward towards the fuel filler inlet. The fuel drain fitting located directly behind the right engine exhaust was missing. Rubber fuel cells are known to collapse in this manner when a fuel filler cap comes loose in flight. The fuel is then sucked out through the filler neck into the low-pressure area above the wing. This occurs faster than the vent system can cope, causing the inner cell to collapse. In this case, the fuel caps were found properly secured. However, the rubber sealing ring on the right fuel cap was perished and cracked in several places. The steel mating ring around the filler neck, which accepts the fuel cap, was also badly corroded over the entire sealing surface area. It is probable that the fuel syphoning began as a result of the poor seal around the cap. The syphoning would have been assisted by the tanks having been filled to the top of the filler neck for the flight. (The tanks had not been filled to this level for at least two years.) The outboard fuel (water) drain fitting attaches to a section of the fuel cell which protrudes through the lower wing surface. This fitting is located immediately behind the right engine exhaust outlet. When the fuel cell collapsed inside the wing, the fitting was unable to pass through the wing cut-out and was pulled from its attachment point on the cell. This then allowed fuel to flow freely into the airstream directly behind the engine exhaust. When the engine start was attempted with the aircraft tail into wind, the stream of fuel was blown directly back against the exhaust outlet. The investigation confirmed the right outboard exhaust as the ignition source for the fire.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Inadequate maintenance of the fuel filler cap.

2. The fuel tanks had been filled to the top of the filler neck.

3. Fuel from the right wing tanks had siphoned overboard, causing the inner fuel cells to collapse.

4. The pilot attempted to start the right engine with the tail of the aircraft into wind.

5. Exhaust gases from the right engine ignited the fuel draining from the tank.

Whilst on a training flight, the pilot attempted to turn the aircraft through 360 degrees as part of an autorotative descent that was commenced at 470 feet above ground level. During the turn the pilot looked inside the aircraft to check the rotor RPM, and on looking outside again he noticed that an excessively high rate of descent had developed. A roll was initiated to bring the aircraft out of the turn, and power was applied. However, the main rotor blades began making the sound characteristic of low rotor RPM and, as ground impact appeared imminent, the pilot attempted a run-on landing. On impact the aircraft was not aligned with the intended landing direction and after sliding approximately 10 metres the right skid collapsed. The main rotor blades impacted the ground, and the upper area of the bubble canopy and the aircraft rolled to a halt on their sides. The pilot had had a lay-off from flying for 4.5 months. He then completed a check flight with the Company Chief Pilot three days before the accident flight. This check flight included a 360 degree practice autorotation from below 500 feet above ground level. Expert opinion was that a person who had not regularly practised this manoeuvre would have difficulty completing it successfully every time, if commenced from below 500 feet above ground level. When the pilot attempted the manoeuvre it was 15 minutes before last light and the eastern sky was losing its definition. As the aircraft rotated in its turn, the pilot would have been presented with a rapidly changing quality of visual cues being presented to him which would have added to the difficulty of accurately flying the manoeuvre. The pilot was too late in his attempt to recover from the manoeuvre.

Circumstances:

The accident flight was intended to recover the aircraft which had been force landed that morning, due to a massive oil loss accompanied by a propeller overspeed. After take-off, the pilot left the landing gear down and climbed the aircraft over land to 1500 feet as he checked the engine instruments. He reported an initial increase in cylinder head temperature, but this was attributed to the landing gear-down climb by the engineer who was following in a helicopter. A short time later, the pilot reported rough running and then the engine vibrated and seized. An attempt was made to reach a clear area on an island, but despite retracting the landing gear, the pilot was forced to land the aircraft in a mangrove-covered tidal plain. The pilot levelled the aircraft over the tree-tops and stalled before cutting through the trees. A heavy ground contact was felt, and the aircraft came to rest in about 13 metres. The pilot egressed unaided after closing down the aircraft. The engine was recovered for inspection. Massive internal damage from a progressive failure of components, due lack of lubrication, is considered to have been the most probable cause of the engine failure. This is traceable to the previous occurrence that day when a massive oil loss and overspeed occurred. Inadequate inspection of the aircraft following the previous unserviceability including a failure to comply with the manufacturer's recommendations, allowed the aircraft to depart on the recovery flight in an unairworthy condition.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Inadequate inspection of the aircraft following a previous major oil loss and propeller overspeed.

2. Forced landing over unsuitable terrain following engine seizure. This accident was not the subject of an on-scene investigation.

Circumstances:

The pilot planned a short flight to Bunbury prior to boarding an international flight from Perth Airport that afternoon. He dipped the fuel tanks and checked the fuel gauge reading against the fuel calibration card, concluding that the aircraft contained about 70 litres of fuel, which was sufficient for the intended flight. Enroute to Bunbury, the pilot noticed that the fuel usage appeared higher than normal but did not take any action to remedy the situation, beyond leaning the mixture. The pilot noticed that both fuel tank indicators were approaching empty when he broadcast the inbound to Bunbury radio transmission. He was not concerned, as a check of the fuel gauge calibration card indicated that there were still 40 litres remaining. Eleven kilometres from Bunbury, the engine stopped and except for one brief burst of power would not restart. The pilot attempted to enter a forced landing pattern two or three times but had to change the selected landing area on each occasion due to a proliferation of power lines in the area. The aircraft eventually touched down on the bank of a river and overturned. A check of the aircraft found that eight and a half litres of fuel remained in the system, this was three and a half litres less than the published unusable fuel for the aircraft. Perusal of the aircraft records indicated that an error had been made during the latest fuel gauge calibration, and the fuel gauge calibration card was inaccurate. It is probable that the aircraft contained much less than 70 litres on DEPARTURE. The pilot sustained facial lacerations when the aircraft overturned on landing. He was not wearing the shoulder portion of the lap/sash seat belt. It is probable that there would have been no injuries if the complete belt had been worn.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Inaccurate fuel gauge calibration chart.

2. Fuel exhaustion resulting in a forced landing on unsuitable terrain.

3. The pilot did not ensure that the complete seat belt was fastened.

Circumstances:

The Gliding Federation Australia investigation reports that after a winch launch the student pilot flew locally for about ten minutes. He then realised that he was getting low and turned back towards the airfield. Late in his approach he saw power lines, dived under them, and was forced to outland in a paddock adjacent to the airfield. At the end of the landing roll the glider collided with a fence and was substantially damaged.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Inadequate circuit planning, probably as a result of inadequate or incomplete training.

2. Lack of situational awareness.

The pilot was carrying out a flight around the Archerfield Training Area. Approaching the southern boundary of the area he heard a change in engine note. The tachometer confirmed a loss of some 200 RPM, however, all other engine instruments indicated normal operating conditions. Full throttle selection failed to produce any change in engine RPM. The pilot elected to divert to Southport for a precautionary landing. After joining the downwind leg of the circuit he found that he was unable to control the engine RPM with the throttle. As a result he was unable to slow the aircraft to the normal landing speed. He decided against shutting the engine down and making a glide approach, as he was concerned that if he misjudged the approach the aircraft could land in the built up areas north of the aerodrome. On downwind once again, the RPM decreased to a level which was too low to sustain level flight. The pilot chose the clearest area in front of him for a forced landing. The area was a swamp and the aircraft nosed over shortly after touchdown. The engine had been overhauled and re-installed in the aircraft, 78 (in service) hours before the accident. The throttle arm linkage had come loose at the carburettor, effectively denying the pilot control of the engine. Examination of the castellated nut, which held the linkage in position, found no evidence that it had been torqued correctly or that a split pin had been installed.

Circumstances:

The student was making his second solo flight. During the approach to land the student realised the helicopter was above the desired approach path. He elected to land on the grass surface a short distance beyond the helipad as he has been taught. The wind was blowing at 10 to 15 knots from the northeast, with the landing conducted in an east south east direction. The pilot said he began to enter the hover and turn the helicopter to the left, into wind. The aircraft continued the left turn, during which it began to move rearwards. The tail skid dug into the landing surface, resulting in the helicopter rolling to the left and striking the ground.

Significant Factors:

The following factors were considered relevant to the development of the accident:

1. Improper compensation for wind conditions.

2. Pilot encountered unforeseen circumstances beyond his capability.

3. Improper operation of primary flight controls.