The pilot had been requested to carry out an aerobatic display over a fair being conducted at the local racecourse. During the display three spins were completed, with each being entered at about 1500 feet agl and recovery effected by 500 feet agl. The display appeared to be finished when the pilot made a low pass from behind the crowd at approximately 100 feet agl and then climbed out for what looked initially like a normal entry to the circuit at nearby Wyndham Airport. However, as the aircraft approached 1000 feet agl it was observed to carry out a spin entry similar to that used on the three previous spins. A spin to the left started and four turns were completed before recovery appeared to commence at about 200 feet agl. The aircraft struck the ground before recovery was complete, still yawing to the left and with the nose attitude about 24 degrees below that required for level flight. Whether or not the entry to the final spin was delibrate could not determined. The pilot was not approved to carry out aerobatic manoeuvres below 3000 feet agl, however, reports indicate that he had previously conducted low level aerobatic displays.

Due to a loose seat belt banging against the fuselage of the helicpoter, the pilot slowed the aircraft and commenced an approach to land as soon as possible. The chosen approach path had a tailwind of between 15 and 20 knots. Shortly after commencing the approach, the rate of descent increased rapidly and the pilot's application of collective pitch to correct the situation further increased the descent rate. During the approach, both the audio and visual annunciators indicated that the engine had failed. The pilot lowered collective but then had to flare as the aircraft was about to impact a small mulga tree. The aircraft cleared that tree but was damaged as a result of a collision with a nearby tree. The rapid rate of descent experienced whilst descending downwind with a low forward speed is typical of an aircraft which has settled in its own main rotor downwash, i.e in a Vortex Ring State. No defect was found in the engine which might have explained the reported engine failure. It is possible that the pilot inadvertantly selected the throttle to the engine shut-off position as he commenced autorotative flight.

The pilot, who had not previously flown this type of aircraft, intended to carry out a circuit and landing. The take-off was reported to be normal, but at a height of about 20 feet agl engine noise ceased and the aircraft nosed down steeply. It struck the ground heavily in a nose low, wings level attitude. It was determined that the fuel tap was still turned off when the take-off commenced and the engine had failed because of fuel starvation. The pilot had been unable to prevent the subsequent stall and had insufficient height remaining to regain control before impact with the ground.

The pilot had not flown for some time and was practicing circuits with her husband who was also a pilot. On downwind, her pre-landing checks were interrupted by a radio call. The aircraft was subsequently landed with the gear retracted. The gear warning horn was not serviceable prior to the flight. After the aircraft was established on final the pilot's husband commenced to stow the headsets and other loose items which were in the cockpit. He did not monitor the approach and therefore did not notice that the pilot had omitted to lower the landing gear.

Circumstances:

The pilot had completed the first leg of a 300 kilometre flight and was positioning the glider so that he could take a photograph of some silos. During the process the main landing gear was released. The pilot leant forward to pull on the landing gear retract column and was afflicted by a painful spasm of the stomach muscle. The pain persisted so the pilot decided to make an outlanding in a large wheat field. The pilot saw a power line near the western end of the paddock but decided to land in the paddock since it was otherwise suitable and he had sufficient height to fly over the wire. However, the glider encountered sink on final approach and collided with the wire. The wire struck the canopy of the glider and arrested its forward motion before the wire broke. The glider then fell to the ground.

Significant Factors:

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

1. The pilot suffered an inflight incapacitation which necessitated an outlanding.
2. The glider encountered an increased sink rate on final approach.
3. The pilot was unable to avoid a collision with a power line.

During cruise the right engine began to surge and vibrate. Normal actions to restore engine performance were unsuccessful and the engine was shut down. About four minutes later the left engine lost power in a similar manner to the right. The pilot carried out a forced landing but the nosewheel was torn off when it struck a ditch. A subsequent examination revealed no evidence of pre-impact defects or malfunctions of either engine which might have contributed to the reported power losses. Atmospheric conditions at the time were conducive to the formation of carburettor icing. The aircraft was not equipped with a carburettor air temperature gauge, and the pilot had not applied carburettor heat until the initial loss of power from the right engine. At the same time, he had moved the mixture levers to the full rich position, which would have reduced the exhaust gas temperature. This in turn would reduce the amount of heat available to disperse any ice accumulation. It was considered probable that if an appreciable amount of ice had formed, there was insufficient time available for it to be dispersed by the heat applied, before the pilot was committed to a forced landing.

After the pilot selected the gear down, he observed that the single gear position indicator light indicated that the gear was down. During the landing roll, as the aircraft slowed down, the left wingtip and left propeller contacted the strip. Subsequent inspection of the aircraft revealed that the left main gear was in the up position. The left gear uplock bracket-block had recently been repaired but the forward hole had been drilled slightly off centre. This caused the bracket to tilt rearward and the block to slip off the uplock roller face and jam against the roller retaining bolt. When the gear was selected down the gear motor drove against the jammed uplock and bent the left retract rod. This allowed the motor to complete its extension cycle and indicate a gear down condition because the indicator switches are located on the activator housing and not at each gear leg.

Circumstances:

The pilot reported that at approximately 150 feet after take-off, the engine power began to reduce and the engine out warning sounded. An autorotational landing was carried out, during which the main rotor blades collided with the tail boom. Inspection of the engine and its components, indicated that a partially blocked fuel nozzle had caused uneven combustion which in turn, resulted in a loss of power output. The nozzle, which had been tested serviceable and installed in the engine one hour prior to the accident, was later found to contain a piece of foreign matter which caused an uneven spray pattern at high operating fuel pressures.

The helicopter was being flown along a watercourse at a height of about 10 ft and an airspeed of about 85 kt. As the pilot rotated the aircraft to commence a climb the rear of the landing skids struck the water. The helicopter pitched forward, overturned and sank. The water surface at the time of the accident was smooth and glassy. The judgement of height above such a surface is difficult. The inexperienced pilot was apparently aware of these difficulties, however, on this occasion misjudged the height of the helicopter above the water as he selected the climb attitude.

Circumstances:

The pilot reported that after touching down on the third landing for the flight, the aircraft began to turn to the right. Corrective action was taken, however, the aircraft yawed sharply to the left and skidded off the left hand side of the runway. The wind was light and variable at the time of the accident.