Circumstances:

The pilot reported he had flown to the property to visit some friends. He overflew the paddock in which he intended to land at a height of 500 feet before deciding to carry out a low inspection run to determine if the surface was suitable for a landing. The pilot advised that he had seen a powerline running parallel to the direction of travel. As the aircraft passed along the paddock it struck an unseen spur line running at right angles to the main line. After severing both conductors, the aircraft was flown for a further kilometre before being landed. During the landing roll the aircraft collided with a contour bank.

Weather conditions were fine with a five knot wind directly down the runway. The student had previously flown gliders and had recently been introduced to ultralight flying. As his last flight had been some six weeks ago a period of dual was being conducted with an instructor. On the third landing the aircraft bounced on touch down and veered left. The student applied power for go around but overcorrected and the aircraft then veered to the right. Concerned that the aircraft would not clear trees ahead the instructor intervened to land the aircraft. A ground loop followed and the aircraft sustained damage as a result. The accident was not the subject of an on scene investigation.

The aircraft was being flown in company with a helicopter. While enroute the pilots had been requested to check the surface of Lake Torrens for suitability for future operations. The helicopter was landed on a section of the lake which was assessed as suitable for the fixed wing aircraft. The pilot of that aircraft also assessed the area as suitable and a landing was made at a touchdown speed of 40 knots. Shortly after the nose wheel contacted the surface it began to sink in the soft ground and the aircraft overturned.

The pilot had obtained a briefing on the strip at the intended destination and was aware that it was in good condition. On arrival a normal circuit was flown and on short final approach the pilot noticed bushes on the strip. He prepared to go around but before this could be effected the nose and left main wheels struck anthills which were obscured by the bushes. The left gear leg was detached and the aircraft ground-looped. The pilot made a navigation error and had made an approach to a disused strip 13 km from the intended destination. The strip had appeared serviceable when viewed from circuit height, but the pilot had not checked the orientation of the strip, which was 20 degrees different from that at the intended destination.

Circumstances:

The aircraft was conducting spraying operations. The pilot reported that the aircraft failed to remain airborne after encountering a severe "willy willy" at the liftoff stage of the take-off. He initially dumped part of the load, then dumped the remainder as the aircraft was making contact with the ground. An area of long grass and thistles then prevented the aircraft from becoming airborne. As a result, one main landing gear was torn off and the other damaged.

Circumstances:

After an uneventful flight to Tambar Springs, two passengers embarked for the return journey to Bankstown. Approaching Scone, unsuitable weather forced the pilot to divert east of track towards the coast. Whilst cruising at 1500 feet AMSL, about two kilometres north of Warnervale, the engine, without warning, suffered a complete loss of power. The pilot transmitted a Mayday call to Sydney Flight Service and positioned the aircraft for a straight-in approach onto runway 17 at Warnervale. He carried out a trouble check and attempted to restart the engine without success. The aircraft passed over the threshold high and fast and landed well down the runway. The pilot was unable to prevent the aircraft from running off the southern end and it came to rest some 150 metres beyond the runway after passing through a boundary fence which damaged both wings. A technical investigation revealed the complete engine failure occurred as a result of the disconnection of the accessory drive gear from the crankshaft. The locating dowl failed due to fatigue after a loss of tension of a bolt attaching the accessory drive gear to the crankshaft. The reason for the loss of tension was not positively established. However, it is possible that a propeller strike, 593 hours prior to the accident, caused the loss of initial torque on the bolt. The propeller strike and subsequent rectification action occurred in the United States of America before the aircraft was imported to Australia.

Circumstances:

The pilot reported that he was aware of the location of the three-cable powerline during his spray runs. He had completed three runs under the line and was conducting a clean-up run at the opposite end of the paddock when he collided with the wires during a pullup. The wire deflector snapped, and the top of the vertical stabilizer and rudder were torn off. The pilot was able to land the aircraft safely. He indicated that he had forgotten about the location of the line when he moved to the other end of the paddock and it was no longer necessary to fly under them.

The aircraft was engaged in night spraying of cotton crops. The pilot had completed about two and one half hours work on two properties, with a short break between tasks, before arriving at 'Ginidgeree'. The night was clear but dark, with a barely discernible horizon on certain headings. The marker vehicles had assumed their positions at each end of the first spraying run when the aircraft arrived over the paddock. Believing the markers to be incorrectly positioned, the pilot elected to fly orbits over the paddock while clarifying his orientation. After several orbits the pilot accepted the marker positions, and the aircraft departed to the north to begin the approach for the first spraying run. During the turn to intercept the inbound track, the aircraft struck a tree then impacted the ground and continued forward for 130 m, shedding components and starting a fire. The pilot suffered minor injuries and evacuated the burning wreckage without assistance. The aircraft had struck the tree in a gentle descent during the turn. The pilot, believing that the aircraft was flying level, did not notice the descent as he was concentrating on lining up for the first spraying run. The pilot held a Commercial Pilot Licence which had been endorsed for night spraying six days earlier. He had about 700 hours experience in agricultural flying, including about 50 hours of night spraying, in Ag waggon and Air tractor aircraft. At the time of the accident, the pilot was wearing overalls, boots, a high-quality helmet and was tightly strapped into his seat. Damage to the helmet indicated multiple impacts including at least one of extreme severity. In laboratory tests conducted overseas, a force of over 300 g was required to produce damage similar to that on the helmet. It is almost certain that, without the helmet, the pilot would not have survived the accident.

Significant Factors:

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

1. The night was dark with a barely discernible horizon on certain headings.

2. The pilot, although qualified in night spraying, was relatively inexperienced in the role.

3. While executing an inbound turn for the first spraying run, the pilot did not realise that the aircraft was gently descending.

At the time of the occurrence, the passenger terminal at Maroochydore was being modernised and expanded. A temporary, one metre high, chain wire fence marked the edge of the apron area in front of the building. The area between the fence and the terminal building was bare sand on which lay various building materials including sheets of roof cladding. Access to this area was restricted by a sign on a fence adjacent to the northern end of the building. However, the new sections of the building were open, displayed no warning signs, and allowed ready access to the apron side of the building. The old section of the building was still functioning as the passenger terminal. Access through this area to the apron was restricted to emplaning and deplaning passengers. Prior to the aircraft's arrival, a group of bystanders, some of whom carried placards, had gathered behind the chain wire fence directly in front of the terminal building. These persons gained access to this area apparently via the northern end of the building. As the aircraft taxied to its parking position in front of the terminal, the bystanders directed abuse at the flight crew. This abuse continued until the aircraft departed. After the aircraft captain remarked to the company airport manager that the bystanders could be in some danger when the aircraft taxied, they were asked by the manager to move. The group moved to the new northern section of the building. Some remained adjacent to the fence on which the warning sign was mounted, others were positioned within the new section of the building behind a low brick wall, while the remainder went to the rear of this section of the building. On taxi from the terminal, the aircraft was required to make a sharp right turn through about 180 degrees. Numerous complaints were received alleging that during the turn, the pilot used excessive thrust, endangering the bystanders. Photographic evidence was obtained showing loose sand and one or two sheets of roof cladding being blown by the jet blast. The Digital Flight Data Recorder (DFDR) was removed from the aircraft and analysed. The only engine parameters recorded by the DFDR system installed in VH-EWB are percentage thrust for each engine. This system provides an indication of developed thrust on each engine and records it as a percentage of maximum thrust by measuring the pressure differential between the jet pipe total pressure and the ambient pressure from the auxiliary pitot static system. Engine control by the crew is accomplished via throttle control of N2 RPM. The relationship between percentage thrust and N2 RPM is exponential so that small changes in N2 at the higher levels produce large changes in thrust. The DFDR analysis showed that taxi was initiated with a thrust of 54 percent. After the aircraft had turned through about 90 degrees, thrust increased to a maximum of 60 percent on both engines over a period of 4 seconds and then decreased to 54 percent over the following 6 seconds. The left engine was at 60 percent for 2 seconds and the right was at 60 percent for less than 1 second. During this time the aircraft turned through a further 90 degrees and the jet blast from its engines would have been directed towards the terminal building. The aircraft was turning into wind during this latter 90 degrees of turn. Because of an unserviceable accelerometer in the aircraft, no valid longitudinal acceleration data was recorded. Consequently, no information was available concerning brake application. Other periods of taxiing were examined for comparison with the taxi thrusts used on this occasion. These showed that up to 57.5 percent thrust had been used during taxiing manoeuvres at other locations. However, because the DFDR recorded data contained no other flight into Maroochydore, no meaningful comparison could be made. In any case, the use of an extra few percent around the 55-60 percent thrust level would not constitute a substantial increase the strength of the jet blast from the engines. Therefore, the allegation that the pilot used excessive thrust on taxi at Maroochydore is not supported by the factual evidence available. Immediately following the occurrence, the aircraft operator ceased to use the parking position directly in front of the terminal building. Also, arrangements were made by the Civil Aviation Authority with the airport owner for a safety officer to be in attendance at the terminal for all jet operations to control public access in the vicinity of the terminal construction area.

Circumstances:

HS-TGC operating as flight TG484 took off from runway 34 on initial climb to flight level 280. At 1518 hours local, following reports from members of the public, Sydney Air Traffic Control advised the crew that an object had been seen to fall from the aircraft shortly after take-off. The captain requested further information before a decision was taken whether to continue the flight or return to Sydney. At 1622 hours the aircraft was transferred to an Adelaide ATC frequency and at 1658 hours a report was passed from the company which provided engineering support to the airline in Sydney. The report indicated two pieces of metal were recovered. They were 30 cm and 45 cm in length and were pieces of an exhaust nozzle although the engine which lost the pieces could not be identified. A recommendation was passed to the captain to monitor all engine indications and if no abnormality were evident, it would be safe to continue to the destination. The captain advised that all engine indications were normal and that the flight would continue as planned. The aircraft landed safely at its destination. After arrival, the long fixed core exhaust nozzle (LFCEN) from number three engine was found to be missing. Subsequently, eight pieces of the exhaust nozzle were recovered in an area approximately 2.4-4.9 km beyond the northern end of runway 34. There were no injuries to persons under the flight path and property damage was minimal. A technical investigation revealed that material failure caused the separation of the LFCEN from the engine body. The attachment fitting which secures the LFCEN to the engine body failed as a result of extensive fatigue cracking. A service bulletin was issued by the engine manufacturer in February 1987 which recommended fitment of secondary attachment hardware for the LFCEN. As an alternative, it was recommended the primary attachment fittings be inspected on a regular basis (every 750 engine cycles) for cracking. The airline complied with the alternative recommendation but with an extension of the time between inspections to every 1,000 cycles. No. 3 engine had completed 666 cycles at the time of failure. In-flight separation of an LFCEN from the type of engine fitted to HS-TGC is an extremely rare event. The engine manufacturer has notified all affected aircraft operators of the circumstances and findings. The manufacturer also renewed its recommendations contained in the service bulletin which advocated the fitting of secondary attachment hardware to the LFCEN. The airline has taken action to ensure a fleet-wide inspection of all LFCEN attachment fittings at the next 'A' aircraft check and fitment of secondary attachment hardware in accordance with the engine manufacturer's service bulletin.

Significant Factors:

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

1. Fatigue cracking of the LFCEN attachment fitting, no. 3 engine.

2. Material failure of the LFCEN attachment fitting, no. 3 engine.