The pilot was in the process of purchasing the "Cygnet" and had flown to Forest Hill to fly the aircraft before the purchase was finalised. On the day before the accident, he completed several flights in the "Cygnet", the last of which resulted in a forced landing after the engine failed. On the day of the accident the pilot planned to return to his home, but the aircraft he had flown to Forest Hill was unserviceable and departure was delayed until the following day. That afternoon when the "Cygnet" had been repaired he made another successful flight in the aircraft, which was also subsequently flown by another pilot. At 1505 hours, the pilot again took-off in the "Cygnet", for a ten minute flight. During this flight several flypasts were made along the strip before an approach to land was made. Witnesses report that the approach was misjudged and after touchdown the aircraft bounced several times before the pilot applied power and carried out a go-around. The aircraft then climbed straight ahead with full power set before making a steeply banked turn onto the crosswind leg of the circuit. A flat tight turn through 180 degrees was then made and the aircraft appeared to witnesses to be flying very slowly. During the turn one witness reported that the pilot's left foot came off the rudder pedal and control was partially lost. After control was regained, the aircraft continued flying slowly, it was seen to oscillate in pitch several times before the left wing dropped and it entered a spin. No change in engine noise was noticed during the spin and the engine continued to operate until the aircraft impacted the ground. Inspection of the aircraft did not reveal any pre-existing fault that would have contributed to the accident. It was subsequently found that the pilot was a diabetic and at the time of the accident he was markedly hypoglycaemic. The erratic way in which the aircraft was flown prior to impact indicates that the pilot lost control of the aircraft due to his being incapacitated as a result of hypoglycaemia.

The pilot carried out a normal full flap approach into a steady 15 knot headwind. Immediately before touch down the aircraft was struck by a strong wind gust from the left. The aircraft yawed sharply to the left and the nose lifted. The pilot applied full power and attempted to lower the nose but the aircraft touched down heavily on its main wheels and tail tie down ring. The aircraft did not bounce and the pilot elected to complete the landing. It was likely that the aircraft had been affected by a willy-willy at a critical stage of the approach. The pilot's recovery actions were unable to prevent the resulting heavy landing.

The pilot was operating a NOSAR NO DETAILS flight and he did not establish the time of last light at Esperance prior to departure from Lake King. In flight the pilot's only navigation was to check that he passed over known features whilst enroute. At a point approximately half way into the 50 minute flight the pilot became concerned about the failing light and he increased power in an attempt to reduce the remaining time interval to his destination. When the aircraft was approximately 15 km short of Esperance the pilot who was unsure of his exact position decided to land in a paddock rather then continue with the flight. The pilot carried out an Authorised Landing Area (ALA) inspection under the constraints of reducing time and light and he did not observe any obstructions other than some trees near the approach end of the paddock. Because of the trees the aircraft touched down well into the paddock and the pilot was unable to avoid colliding with a fence and water trough which he had not seen prior to landing. The collision occurred approximately 30 minutes prior to last light. The light was poor due to an extensive cloud cover. Esperance airfield was fitted with a Pilot Activated Lighting (PAL) system but the pilot who was aware that the system was there did not know the frequency needed to operate it. The pilot did not seek help from Flight Service prior to his precautionary landing.

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.

The pilot was nearing the completion of 50 hours of flying under the supervision of the company chief pilot. For this flight the chief pilot decided to travel in the passenger section of the aircraft, to demonstrate his confidence in the pilot. The aircraft was rotated at 90 knots and just after liftoff, at about 50 feet above the runway, the pilot heard a loud bang and noticed smoke coming from the left engine. At about this time the chief pilot started to call instructions to the pilot. Power was increased on the right engine and the landing gear and flap retracted. However, the aircraft began to descend and veer to the left before touching down on its undersurface. It skidded for 103 metres and came to rest 155 metres to the left of the runway centreline abeam the upwind threshold. An inspection of the left engine revealed that the thread of a nut on one of the number 2 cylinder connecting rod big end bolts was stripped, causing the big end to become detached from the crankshaft and forcing the connecting rod through the crankcase. The reason for the stripping of the nut thread could not be established.

The aircraft owner was flying the aircraft under the supervision of the pilot-in-command. A landing was made on the grass to the south of the gravel strip. After a small bounce on initial touchdown, the aircraft landed firmly and the right wheel penetrated the ground to a depth of about 5 cm. The aircraft tipped forward, the propeller struck the ground and the aircraft overturned. The aircraft owner had elected to land on the grass adjacent to the gravel strip in order to prevent possible stone damage to the aircraft paintwork.

Circumstances:

During a short ferry flight to a property for the purpose of conducting shooting operations, the pilot noticed a burning smell in the cockpit and a glow beneath the rear seat. Following an emergency landing the pilot evacuated the aircraft before it was consumed by fire. The pilot reports that he had been carrying signal flares, fuel, oil, grease and dirty rags on and beneath the rear seat. He further reports he had been smoking prior to becoming aware of the burning smell. The Fire Officers Investigation report confirms that the fire had originated in the cockpit and that the source of ignition had probably been a lighted cigarette butt which had come to rest on the dirty rags.

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.

The pilot intended to carry out a touch and go landing at the strip, from which he had operated on numerous occasions. He reported that the aircraft floated for some distance before touchdown, whereupon he immediately selected flaps up and applied full power. The aircraft started to swing towards the left, and suspecting an engine failure, the pilot shut down both engines and applied maximum braking. He slewed the aircraft to the right to avoid a dam at the end of the strip. The aircraft was arrested by a wire fence beyond the end of the strip, with the left maingear leg torn off. It was found that the left flap had not retracted, although the right flap had retracted normally and the cockpit indication was that the flaps were up. The strip was narrower than required for an ALA, and was bordered on each side by a one metre high oat crop. As the aircraft swung to the left, it is likely that retardation of the crop on the left wing added to the drag on that side. The aircraft had landed with a tailwind component. During the investigation, it was reported by several persons that asymmetric flap retraction was a known problem on this aircraft type, and was caused by dirt or other contamination of the flap tracks. The symptoms of the malfunction are similar to those associated with a loss of engine power on the particular side. The pilot had not been aware of the problem.

Circumstances:

The student pilot had been authorised to carry out a one-hour flight in the Bankstown Training Area for the purpose of practising steep turns and simulated forced landing approaches. The weather was fine and cool with light winds. Prior to DEPARTURE the student had been briefed by his instructor on the conduct of the flight. This had included specifying a minimum go-around height for forced landing approaches. The student was instructed to return to Bankstown by 1700 hours. The aircraft failed to return by the appointed time and, despite extensive efforts, was not located until the following morning. The wreckage was found in an open area and damage was consistent with the aircraft having struck the ground at a high rate of descent with a very low forward speed. Evidence was found to indicate that the engine was delivering little or no power at impact. Subsequent testing demonstrated the engine was capable of normal operation. A comparison of the actual weather conditions at the time of the accident and a carburettor icing probability chart, showed that serious carburettor icing was probable at descent power. The circumstances of the accident were consistent with the engine failing to respond to the opening of the throttle following a prolonged descent at idle power, following a practice forced landing approach. The student may have diverted his attention from flying the aircraft while attempting to restore power, resulting in a loss of control at low altitude. It was not possible to determine if the carburettor heat control had been operated in accordance with recommended procedures.

Significant Factors:

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

1. Weather conditions conducive to carburettor icing during descent

2. Probable prolonged descent at a low power setting.

3. Probable loss of power due to carburettor icing.

4. Student pilot may have diverted attention from the operation of the aircraft.

5. Loss of control at low level.