The pilot stated that he noticed a large piece of timber on the runway in line with the nosewheel during the landing flare. Power was applied and the nose wheel was raised to avoid the timber. During the subsequent landing the nosewheel struck the runway prior to the mainwheels. After returning to Mackay, the aircraft was inspected by an engineer who discovered damage to the firewall.

VH-AMM departed Sydney at 1426, tracking via Nowra to Moruya and cruising at flight level 160. Nowra control zone extends approximately 19 miles south of Nowra. The base of the control area south of this is 8000 ft, until 30 miles from Nowra. From 30 miles south of Nowra to Moruya the base of controlled airspace is flight level 150.

VH-MJH departed Moruya at 1442, tracking via Nowra for Sydney and cruising at 7000 ft. Advice of this departure was passed by Melbourne flight service to Nowra air traffic control.

At 1448 Melbourne air traffic control advised Melbourne flight service that VH-AMM was on descent 12 miles south of Nowra and would be calling flight service. The descent was continued and as instructed by air traffic control the crew called on the flight service frequency. An estimate of 1501 for arrival at Moruya was given to flight service.

Nowra air traffic control had observed both aircraft on radar and contacted flight service to pass an instruction to VH-AMM to maintain 8000 ft. An error in the call sign used by Nowra air traffic control caused a delay in transmission of this instruction. When the message was passed to the crew of VH-AMM at 1451 they advised they were climbing back to 8000 ft from 7700 ft. The two aircraft passed at about this stage.

Melbourne flight service was required to pass traffic information to both aircraft about each other but had not done so. Nowra was not a compulsory reporting point, and the Melbourne air traffic controller did not pass a position report for Nowra to flight service. Because there was no position report the controller had advised flight service when the aircraft was on descent.

The flight service officer did not have the flight progress strip for VH-AMM in the active bay until after the controller's report of the aircraft being on descent. The procedures adopted left limited time for the flight service officer to assess the traffic situation.

Significant Factors

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

1. Limited time period available to the flight service officer after advice of VH-AMM on descent.

2. Flight service officer did not pass the required traffic information to either aircraft, reasons undetermined.

In cruise at 10,000 ft the pilot noticed the left alternator light had illuminated, and that the right alternator was now taking all electrical loads. The left engine power then reduced from 31hg to 23hg, suggesting to the pilot that the turbo-charger was malfunctioning. As the aircraft was now unable to maintain its cruise altitude the pilot requested a descent to 7,000 ft. He also requested an airways clearance to return to Parafield.

He changed the left fuel tank selection from the main to auxiliary and turned the left fuel boost pump on. This restored engine power for a short period of time before it suffered a complete failure, followed by a complete loss of electrical power and smoke entering the cabin.

The pilot feathered the left propeller and turned the fuel selector and all electrical switches off. He maintained communications with Adelaide FIS using a mobile telephone. A successful single engine landing was made after the pilot manually extended the landing gear.

An investigation indicated that the alternator field wire had chaffed on the engine fuel supply line, wearing through its insulation which allowed the barbed wire to then arc on the line, eventually burning a hole through it. The ensuing loss of fuel supply through the hole, with associated loss in fuel pressure, contributed to the reduction of engine power. Activation of the fuel boost pump assisted in restoring some pressure, and power.

Fuel spraying from the holed line was ignited by the arcing alternator field wire, causing fire damage to the wing leading edge skin, wing structure rear of the firewall, oil pressure, hydraulic and fuel supply lines, and the nacelle fuel tank and vent lines. The electric loom between the engine and cabin had the insulation burnt off, allowing it to short circuit and cause the electrical failure. The magneto earth wires, being part of this loom, and also bared of insulation, grounded both magnetos, shutting down the engine.

The engine failing due to the grounded magnetos, and the pilot's action of turning the fuel off, probably deprived the fire of fuel before it became established, and self-extinguished.

The pilot of VH-UBC reported at Rugby at 1725, cruising at 10,000 ft and estimating Holbrook at 1759. The pilot of VH-MJH reported at Yass at 1730 at 10,000 ft and estimating Wagga at 1755. Both aircraft were operating outside controlled airspace and the tracks of the two aircraft crossed.

The two aircraft passed in close proximity. No traffic information had been passed by Melbourne flight service to either aircraft. The flight service position was manned by a trainee under the supervision of a flight service officer who was rated to operate that area. Neither person had noticed the potential conflict.

The area in which the aircraft were operating has a high level of complexity for flight service. The workload at the time was assessed as moderate.

Significant Factor

The following factor was considered relevant to the development of the incident:

1. Neither the flight service officer nor his trainee detected a situation of potential conflict.

The owner/pilot advised that he was practising an aerobatic sequence for a future airshow when the engine suddenly suffered a partial power loss. At the time the aircraft was vertical. The pilot pushed over to level flight at about 1000 ft AGL and 80 kts. Then the engine stopped completely. He performed a forced landing in a nearby paddock. The aircraft touched down at approximately 115 kts. During the landing roll the aircraft flipped twice onto its back before coming to rest upright but nose down.

Subsequently an engineer discovered that the crankshaft thrust bearing had seized. The pilot and the engineer believe that, during aerobatic manoeuvres, the oil pickup pipe had been exposed and sucked air, thereby starving the thrust bearing of oil.

This particular aircraft has a more powerful engine installed than the standard Pitts. The additional horsepower enables very high-performance aerobatics.

The owner/pilot, his engineer, the manufacturer and the CAA are involved in achieving an improved oil supply to the thrust bearing before the engine is returned to service.

Significant Factors

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

1. The crankshaft thrust bearing was inadequately lubricated during aerobatic manoeuvres.

2. The crankshaft thrust bearing seized and stopped the engine.

3. During the landing roll, the aircraft encountered an undulation and overturned.

The DHC-8 was inbound to Lord Howe Island and had made all necessary radio calls on the CTAF frequency. As the aircraft passed overhead the airport prior to landing, a Cessna 172 was sighted about 300 ft directly above. Normal radio communications were subsequently established between the aircraft and both landed without further incident.

The pilot of the Cessna later reported that he had been conducting a local flight around the island and considered that VHF communications may have been adversely affected by the mountainous terrain. He thought that was probably the reason why he had not heard any inbound radio reports by the crew of the DHC-8.

The airways clearance for VH-FKFs departure was runway 16, Strathbogie 1 SID. Soon after VH-FKF became airborne, the Departures radar controller noted VH-FKF turning onto an incorrect heading and queried the pilot. At about the same time the crew realised that they had not selected Fentons Hill VOR but still had Melbourne VOR selected to avail of the international DME. For a short time VH-FKF was intercepting the 200 deg. radial from Melbourne instead of from Fentons Hill. There was no breakdown in separation with other aircraft.

VH-LIH was tracking out of Albury for Sydney and was cleared to climb to flight level 120. VH-FNE was inbound for Albury, from Sydney, initially maintaining flight level 230. Because one of the radar stations was out of service the radar coverage in that area was unreliable and procedural separation was employed. The crew of VH-FNE were given descent to flight level 120, in error. The air traffic controller had intended to descend VH-FNE to flight level 130.

The crew of VH-LIH requested a clearance to climb to a higher level. This was not allowed as the controller mistakenly believed that VH-FNE was at flight level 130. The controller gave both crews traffic information on each other and asked them to report sighting and passing each other. In response the crew of VH-FNE told the controller they had been cleared to flight level 120, were currently at flight level 126 and were climbing back to flight level 130. Following discovery of the error in giving VH-FNE flight level 120, this aircraft was maintained at flight level 130 until it had passed VH-LIH.

Significant Factor

The following factor was considered relevant to the development of the incident:

1. Incorrect level clearance issued by the air traffic controller.

The pilot reported that the accident occurred at the end of the sixth leg for the day. The landing gear had been working normally. He had obtained a safe landing gear indication prior to landing. The right landing gear collapsed as the aircraft slowed after the touchdown. Inspection indicated that the torque link had failed in overload.

Subsequent engineering investigation indicated that a torque link retainer circlip had fallen off. The torque link's action had prevented the oleo piston from falling out until the link itself failed.

A similar problem had been detected during a scheduled inspection completed 20 flying hours prior to the accident. The clip was found to have fallen off and become stuck in the landing gear upper trunnion. The gear was only dismantled sufficiently for the clip to be replaced.

The factors that led to the circlip falling out were not determined at the time of the scheduled inspection and could not be determined after the accident as the circlip was not recovered.

Mariner 398 was tracking from Richmond to Nowra, via Camden and Wollongong. The crew had planned at 8000 ft but due to other traffic the aircraft was restricted to 7000 ft initially. The track took the aircraft close to D595 which is used for parachuting at Wilton. At 1215 the aircraft was approaching Camden.

VH-WRT departed from Wilton at 1210 for parachute operations and requested clearance to climb to flight level 130. The pilot was told by the sector 12 air traffic controller to climb to 7000 ft and remain within 3 miles of Wilton.

The sector 12 air traffic controller co-ordinated details on VH-WRT, including the 7000 ft altitude limit, with Sydney departures south. In response the controller was given identification on Mariner 398 and told that Mariner 398 was at 7000 and would call sector 12, eventually, at 8000 ft.

The sector 12 controller told the pilot of VH-WRT, at 1218, to maintain present altitude. The pilot acknowledged and said he was at 6300 ft. Subsequently the sector 12 controller passed traffic information on Mariner 398 to VH-WRT. The two aircraft passed with 700 ft vertical separation and one mile horizontal separation. The minimum separation required was 1000 ft vertical or 5 miles horizontal.

Significant Factor

The following factor was considered relevant to the development of the incident:

1. A lapse on the part of the sector 12 air traffic controller meant that the required separation was not applied.