The aircraft had not flown since December 1985 and had been parked in the open. The Maintenance Release had expired, and a Permit to Fly was obtained to allow the aircraft to be ferried to Parafield for maintenance. When the gear was lowered for landing, only the nosegear indicated that it was down and locked. Recycling the system did not result in locked indications being obtained for the maingear, although to persons on the ground it appeared to be down. During the subsequent landing roll the right gear collapsed. The aircraft had been inspected prior to the flight and the engineers had noted that the gear bearings were dry and slightly corroded. They did not bring this to the attention of the pilot and he did not detect the condition during the preflight inspection. When the gear failed to fully extend prior to landing, because of lack of lubrication and corrosion, the pilot discussed the situation with an engineer on the aircraft and they decided that the fault was probably in the gear position indication system. As a result no attempt was made to lower the gear using the emergency system.

Following the first 50 hour oil change after a recent overhaul, the engineer who completed the overhaul and service, arranged for he and his wife to accompany the pilot on a scenic flight of the local area. The flight was conducted at an altitude of about 400 feet above ground level and proceeded normally for about 15 minutes until the engine suddenly lost power, it then ran roughly momentarily, before stopping. The pilot attempted to land the aircraft in the only available area, a confined swampy area, but during the approach it struck a large tree and crashed into the swamp. The inspection and testing of various components of helicopter was hampered by the aircraft having been submerged in the swamp, and no reason for the apparent loss of power could be determined.

The pilot arranged for a check flight in the aircraft, as it was a type he had not flown for some time. The instructor commented that as the pilot made rudder corrections during the takeoff roll, he also inadvertently applied light braking. After a period of general flying, the aircraft was returned to the circuit for a landing in moderate crosswind conditions. Touchdown was made in a three-point attitude, but shortly afterwards the aircraft commenced to swing to the right. Corrective measures by both pilots were unable to arrest the swing and the left gear subsequently collapsed. The pilot had used left aileron and right rudder inputs to align the aircraft at touchdown, and had possibly inadvertently applied braking to the right mainwheel.

The pilot was approaching to land in 10 knot crosswind conditions. Turbulence was encountered in the circuit area, and the pilot elected to approach at 80 knots with 20 degrees of flap selected. After a normal flare, the aircraft floated for half the 610 metre strip before touching down. The pilot applied heavy braking, but was unable to stop the aircraft within the confines of the strip. Damage was sustained as the aircraft passed through three drains. The approach speed was higher than required for the existing conditions. The strip sloped down in the direction of landing and it is probable that a tailwind existed at the time of landing.

The pilot reported that prior to takeoff he dipped the fuel tanks and determined that there was sufficient fuel for the flight over his property. During the flight the engine lost all power and the pilot was committed to a landing in a treed area. After touchdown the left wing struck a tree and the aircraft swung to the left causing the right wingtip to contact the ground. The pilot subsequently dipped the fuel tanks and found they contained only a small quantity of unuseable fuel. This accident was not the subject of an on-site investigation.

After the parachutists exited the aircraft the pilot closed the door and positioned for a landing on the 24 strip. The aircraft was established on final at an indicated airspeed of 65 knots and as the pilot was checking the airspeed indicator, the aircraft suddenly yawed to the left. The pilot immediately applied full right rudder, levelled the wings, and landed the aircraft on the left side of the strip. Investigation revealed that the left wing of the aircraft had struck a sapling, about 4 metres above ground level, 78 metres short of the end of the strip.

About 20 minutes after take-off on the return leg of a charter flight and while cruising at 4500 feet amsl, the right engine suddenly lost all power. The pilot reported that he was unable to restore power, and he elected to land at a nearby ALA. From the downwind position a continuous left turn was flown to align the aircraft with the strip. On short final approach the left engine also lost power and the aircraft touched down short of the strip boundary. It ran through two fences and the nosegear collapsed after striking a dirt bank. The flight was the first one in the aircraft type for the pilot in an unsupervised capacity. Investigations carried out at the accident site revealed that there was adequate fuel remaining in the main tanks, although the auxiliary tanks were virtually empty. Both engines were started and ran normally, and no fault was subsequently found with them that might have explained the power losses. The pilot did not have a detailed knowledge of the fuel system, and it was considered likely that he had mis-managed the system.

The pilot was engaged in spraying a small crop of tomatoes. This was the first time he had sprayed this paddock. The farmer provided him with a map of the area to be sprayed, but the powerlines were not marked on the map, so a briefing was conducted on the location of the powerlines. There was a set to the north of the paddock and two sets to the south. Before he commenced spraying, the pilot conducted an aerial inspection of the area. During the aerial inspection he was in radio contact with the farmer and believed he had located all the powerlines. Shortly after commencing the job, the pilot manoeuvred the aircraft for a run in the northerly direction. His intention on this run was to fly below a powerline that on previous runs, because of the disposition of that particular line, he had flown over. When manoeuvring to fly below this line, the aircraft hit another line 80 metres to the south. The pilot was not aware of the presence of the line the aircraft struck. The aircraft hit the ground and was destroyed by the impact and the resulting fire. The briefing received by the pilot was inadequate.

The pilot stated that he selected gear down but did not check for a down and locked indication. After having kept sufficient power applied to land well down the runway, the pilot heard the gear warning horn immediately prior to touchdown, but could not prevent the aircraft landing with the gear retracted. When the pilot purchased the aircraft it had been fitted with an unguarded switch type circuit breaker adjacent to the gear selector handle, and a receptacle for a remote gear switch. These modifications, which had not been approved by the Department of Aviation, were apparently designed to allow the gear to be raised or lowered from outside the aircraft during maintenance checks when the aircraft was supported by jacks. When selecting the gear down on this occasion, the pilot had evidently knocked the circuit breaker to the "off" position, removing electrical power to the circuit. Neither the pilot nor the passenger, who held a current Commercial Pilot Licence, realised that there were no aural or aerodynamic indications associated with the extension of the gear into the airstream when the gear was selected down.

The pilot in command was continuing a mustering endorsement which had been commenced the previous day. After flying for about 85 minutes the pilots stopped for a break of some 30 minutes. About 75 minutes after flying had recommenced a person on the ground heard a thump, and the wreckage of the aircraft was discovered shortly afterwards. It had struck the ground in a steep nose down attitude while spinning or turning to the left, about 270 metres to the south of the 30 strip. Investigation revealed that, at some stage prior to the final impact with the ground, the undersurface of the left wing had contacted the ground, causing left aileron failure followed by a loss of controllability. Medical evidence indicated that the pilot may have suffered a partial or complete loss of consciousness due to a pre-existing heart condition. However, it could not be determined whether this was a factor in the accident.