During a flight involving stock spotting at 700 ft above ground level, the engine began to vibrate and then lost power. The pilot was able to restore power for about a minute but then was unable to maintain level flight. He landed the aircraft in a small clearing in the scrub. Shortly after touchdown, the nosewheel struck a log and the aircraft nosed over. The pilot reported that he crawled quickly away from the aircraft as fuel was leaking from the tanks.

A licenced aircraft maintenance engineer later reported that he had investigated the power loss and could not find any defects. He started and operated the engine for at least 30 minutes without fault. He ventured that carburettor icing may have been the cause of the power loss.

The Bureau of meteorology analysis of the temperatures indicate that the dewpoint was 6 degrees C and the estimate for the dry bulb temperature was 15 degrees C. These conditions with 20% relative humidity are well outside the range where carburettor icing could be considered a factor.

The reason for the power loss has not been determined.

There were four aircraft operating in the circuit for runway 31R when the pilot of an inbound Grumman AA5 aircraft, VH-IFN, contacted Moorabbin tower at the ACADAMY reporting point. The first aircraft in the sequence was Cessna 172 VH-APF, followed by two similarly coloured Piper PA28 Cherokee aircraft VH-HQK and VH-AFH, and a Cessna 152, VH-NAK.

The controller decided to slot IFN behind the second Cherokee, AFH.

The controller instructed IFN to join base and report at 3 miles. The pilot of IFN acknowledged the instruction. Shortly afterwards the second Cherokee, AFH, called "downwind touch and go" and was instructed to "follow the Cessna (APF) late downwind" The pilot of IFN reported at 3 miles and was advised that he was number 3 for landing, and to follow the Cherokee on mid downwind.

The pilot of IFN advised that he had "traffic sighted and I'll slow down to follow". IFN has a circuit speed some 20 knots higher than the PA28 that he was following. The weather was hazy, and visibility was approximately 3NM, but visibility was reported to be slightly less in the sector from ACADEMY to runway 31R.

Shortly after IFN had made the 3 miles call, HQK, the first Cherokee, called "downwind".

The controller now realised that the pilots of the two PA28's had reported their positions in such a way that the controller thought they were in the reverse order to that in which they actually were. This took a little time to identify and rectify but did not change the order of the sequence in relation to the pilot of IFN, who was still following two PA28s.

When the controller gave the pilot of IFN his landing sequence number, he referred to him being number 3 to land when there was actually 3 aircraft between him and the runway threshold. There was also the C152, NAK as number five in the sequence.

As the sequence progressed, the first of the five aircraft involved, APF, commenced a touch and go. The pilot temporarily lost control of the aircraft and departed the sealed runway onto the grass strip. The controller concentrated on this event in order to closely monitor proceedings. The pilot of APF finally regained control of the aircraft and successfully became airborne. The controller had been unsure if the pilot of APF was going to avoid an accident and had sent round HQK, the first of the PA28 aircraft. He then needed to closely monitor the flight paths of APF and HQK to ensure no conflict occurred. He instructed HQK to turn early to avoid APF and to rejoin the sequence behind the last aircraft, the C152, NAK.

While the controller's attention was occupied with the runway separation problems, IFN overtook AFH, reportedly passing about 2m directly over the top of AFH. The pilot of AFH took avoiding action and advised the controller of the near miss. The controller observed the closeness of the aircraft and sent IFN around. The pilot of IFN reported that he did not at any stage see AFH.

Analysis

The pilot of IFN did not sight AFH at any time, most probably because AFH was below and ahead of him, and because the pilot of IFN was only expecting to see two aircraft ahead of him. He therefore was maintaining clearance from, and following, the first of the two Cherokee's rather than the second.

When the controller gave initial traffic instructions to the pilot of IFN, he decided to only include the two PA28s in the sequence ahead of IFN. This decision may have confused the pilot who, after initially turning to follow the second PA28, may have seen the C172 and the first PA28 as the two aircraft ahead when subsequently checking the preceding traffic. The fact that the two PA28s were of similar colour schemes would have contributed to any misidentification by the pilot and the reduced visibility further restricted his ability to observe all aircraft in the sequence.

When the C172 was cleared to commence a touch and go, the first PA28 was on base leg and had passed mid-base position. The second PA28 was on downwind about to turn base. Therefore, although being told that he was number three in the sequence, the pilot of IFN had three aircraft between late downwind and the threshold of runway 31R.

As a result of the confusing position reports given by the pilots of both PA28s, the controller's attention had been concentrated on establishing the actual sequence of these two aircraft until the near accident occurred on the runway. This action did not affect the sequence from the point of view of the pilot of IFN, or from the air traffic controller's traffic plan, other than the order of the two PA28s.

Because of the near accident involving the touch and go landing of the C172, the controller's attention was focussed on his primary functions of runway separation and safety when the track of IFN started to conflict with that of the second PA28, AFH.

Significant factors

1. The controller indicated to the pilot of IFN that there were two aircraft ahead of him in the sequence, when there were, in fact, three.

2. The visibility was such that spotting and recognising aircraft was difficult.

3. The controller's attention was occupied with his primary function of runway separation at the time that the tracks of IFN and AFH came into conflict.

VH-OZT, a Piper PA31 Chieftain was operating Flight 102 from Wynyard to King Island and then to Moorabbin. On arrival at King Island, when the pilot selected the landing gear down, the red gear-unsafe warning light illuminated. None of the three green gear-extended lights illuminated, and the gear selector did not return to neutral position. A pilot in another aircraft at King Island viewed OZT in flight and advised that the gear had not extended but that the main landing gear doors were open. The pilot of OZT then elected to proceed direct to Moorabbin. En route he advised Air Traffic Services (ATS) of the gear unsafe condition so that emergency services would have ample warning to prepare for his arrival. At Moorabbin he flew passed the control tower several times to enable company engineers and a Civil Aviation Safety Authority (CASA) flying operations inspector to view the aircraft, assess the problem and advise the pilot of actions to be taken.

All attempts to lower the gear, including manual extension, were unsuccessful. To minimise the risk of injury and damage to the aircraft, the pilot was advised to land on the hard surface in preference to the grass area beside the sealed runway. After confirming that emergency services were in attendance and with the emergency checklist items completed, the pilot landed the aircraft on runway 35 left.

While retrieving the aircraft from the runway, engineers found that the hydraulic hand pump pressure line had cracked. This allowed the hydraulic oil from the landing gear system to be pumped overboard, initially by the engine driven pumps and subsequently by the manual pump. With the loss of all of the oil, there was no means of extending the landing gear in flight.

A metallurgical examination of the hydraulic pressure line concluded that the cracking was caused by fatigue initiated in a small region of intergranular cracking created by the action of a corrosive environment. The approximate time in service for the hydraulic line was 21,000 hours.

Emergency response aspects

The Melbourne Metropolitan Fire Brigade (MFB) is the fire authority for all emergencies within the perimeter of Moorabbin airport. However, if an aircraft emergency occurs outside the airport boundary, the attending fire service may be the MFB or the Country Fire Authority (CFA). Both the MFB and the CFA have limited experience in aircraft rescue firefighting roles.

When notified of the emergency situation, an MFB officer proceeded to the control tower to coordinate rescue and firefighting activities. Prior to OZT landing he consulted with Federal Airports Corporation (FAC) officers, company pilots endorsed on the PA-31 Chieftain, the company maintenance controller, a CASA flying operations inspector endorsed on the PA-31, and the tower controller. The fire officer maintained radio contact with his fire crew who were awaiting the arrival of OZT. While in the control tower, the fire officer received details of the aircraft and the aerodrome layout, and radioed relevant information to his crew.

Two concerns were subsequently raised by those who responded to the emergency. The first involved media representatives who made their way to the disabled aircraft without first gaining permission. The FAC safety officer had secured a small area around the disabled aircraft but was unable to prevent unauthorised access by the media who had climbed over a fence and made their way to the aircraft. When the unauthorised access occurred, the tower controller monitored movements of both aircraft and personnel to ensure safe operations were maintained. He advised that if necessary he would have closed the airport to all aircraft arrivals and departures. Other media personnel who had sought permission to gain access to the aircraft were ferried to and from the aircraft by a safety officer.

Concern was also expressed about ease of access to the runways when the control tower is not manned. It was determined that for an emergency after the hours of tower operation, local police should guard the wreckage, keep spectators away and control the media.

The second concern involved the capability of the MFB and the CFA to cope with an aircraft emergency because of limited training in aircraft RFFS. The Manual of Air Traffic Services (MATS) (reference 17-6-1 paragraph 15) states that where there is no airport fire service, in the event of an emergency, ATS will activate the airport emergency procedures. Local fire service personnel rarely attend an aviation emergency. It cannot be assumed that the local firemen will be aware of all the risks to themselves, or to those they may attempt to rescue from an aircraft. Similarly, the coordinating fire officer may not be familiar with the possible hazards which could be ascertained from aviation specialists.

The current Moorabbin Airport Emergency Procedures includes a checklist item: "Aircraft type (basic description)". It was considered that being advised of a basic description might be inadequate in situations where an aircraft is equipped with hazardous equipment, such as medical oxygen cylinder(s) fitted to ambulance aircraft.

The safety of local fire crews, and persons to be rescued, would be enhanced if airport emergency procedures included a checklist item to cover the hazards associated with the specific aircraft. Information should be obtained from personnel familiar with the aircraft.

Safety Action

The Bureau is currently examining the adequacy of emergency response procedures at airports that are not normally supported by specialist aviation rescue and fire fighting services.

After departing Dubbo for Sydney, whilst climbing through 7,000 ft, the right engine fire warning illuminated momentarily with associated aural warnings, but ceased before any crew action could be taken. As the warning was assessed to be erroneous, the captain elected to continue to Sydney, where the aircraft landed without further incident.

Whilst subsequently holding on taxiway 'Golf', enroute to the eastern apron, the right engine fire warning again illuminated and remained on. The engine was shut down as a precaution and the engine fire phase one drills carried out. As the fire warning ceased, the fire detector fail caution light illuminated. The captain ordered a full shutdown, and aircraft evacuation. There were no injuries, and an inspection of the aircraft revealed no evidence of fire.

An engineering investigation revealed that the engine fire detector loop connections were contaminated with oil. The connectors were cleaned, and the fire detector unit changed. The system then tested normally, and the aircraft was released for service. However, during subsequent operations further erroneous fire detector failure and fire warnings occurred. Further investigation, including wiring insulation checks, found a chafed wire to the control unit, in the cabin above a passenger overhead locker. Insufficient security of the wire had allowed it to sag and rub against the locker hardware. The operator reported that a fleet inspection indicated this was an isolated problem and no further action was required.

As the aircraft climbed through FL380, approximately 110 NM from Brisbane, the crew heard a loud bang and observed the left engine Exhaust Gas Temperature (EGT) rise to 1100 degrees C. The crew carried out a precautionary engine shut down and the aircraft was returned to Brisbane where it landed safely.

Analysis of the aircraft's Flight Data Recorder (FDR) showed that until the EGT rise, the engine operation was stable with indicating parameters within the normal range. The EGT rise was accompanied by the overall decrease of other engine parameters.

The engine strip examination revealed that most of the high pressure (HP) turbine blades and guide vanes were either missing or burned away, while the rest of the engine was free of damage.

Examination of the blades revealed that failure of the turbine was precipitated by failure of one blade, which was found to have contained a fatigue fracture initiating from inter granular oxidation inside the blade's cooling channel. The separated blade then damaged the rest of the HP turbine. The blade part number was 1778M31G01.

The engine had accumulated 505 hours after overhaul during which all of the HP turbine blades were replaced by a mixture of new and overhauled blades. The blades were supplied by the engine manufacturer.

The damaged blades were returned to the engine manufacturer for examination.

Safety action

The aircraft operator experienced a similar blade failure in 1995, where the blade part number was the same. As a result of this occurrence, the operator has discarded all HP turbine blades of that particular part number.

When approaching the aerodrome, the crew made the appropriate CTAF calls, with no response. At 1,500 ft, just before turning crosswind, a single engined Cessna aircraft was observed about 800 m to the right and about 200 ft below. No response was heard after further calls on CTAF. The crew was unable to identify the aircraft.

The pilot suggested that the Hervey Bay / Maryborough area be made an MBZ due to the number of airline flights into the area each day, and the traffic density associated with the two aerodromes.

Advice of a safety deficiency has been raised and is being considered. The situation is common to other aerodromes subject to frequent airline operations.

Piper Cheyenne 111 aircraft VH-NMA was on a charter flight from Mangalore Vic. to Point Cook Vic. via Fentons Hill and Melbourne. The weather was clear with unlimited visibility. The flight was conducted under Instrument Flight Rules, cruising at 10,000ft. The normal crew compliment for this aircraft is 1 pilot, however for this flight, the charterer had specified that the crew shall consist of 2 pilots.

Approaching top of descent the crew selected and identified the Point Cook NDB and also entered the coordinates into the GPS. Descent to 9,000ft was commenced overhead Fentons Hill which left 27 track miles to run to Point Cook. The intention was to join a right downwind pattern for a landing on runway 35.

Clearance for further descent to 5,000ft was received after a change of frequency from centre to approach. At this stage an airfield was very close and the co-pilot pointed it out to the pilot-in-command who agreed it was Point Cook. The pilot-in-command then became engrossed in descending from 5,000ft as the airfield was by then almost under the aircraft. The crew did not refer to the on-board navigation equipment to confirm the aerodrome was Point Cook, nor did they refer to any topographical information. In fact they were descending over Laverton airfield.

After cancelling SAR with Melbourne the crew joined the circuit and landed at Laverton which is 5 nm north of Point Cook.

Laverton airfield is a decommissioned RAAF base with a similar runway configuration to Point Cook. Although decommissioned, there were 7 windsocks still in place, only one of which was marked with a cross to indicate that the airfield was closed. However, crosses had been placed on the runways to signify that they were not to be used. The crew had seen and discussed the crosses as they were approaching to land: they mistook them as displaced threshold markers and commented that the NOTAMS did not mention a displaced threshold at Point Cook.

Laverton is surrounded by major road, rail and suburban infrastructure while Point Cook is immediately adjacent to Port Philip Bay with substantial open farmland nearby.

The crew agreed that the misidentification occurred because of many factors some of which included:

- a late descent clearance,

- pre-occupation with loosing altitude

- lack of attention to topographical details

- lack of attention to available navigation aids

- reliance of runway layout and orientation as the sole means of identification,

- lack of situational awareness about the reason for the crosses on the runway ,and

- changing from instrument flight rules to visual flight rules without ensuring that relevant navigation processes were co-ordinated.

The operator has required all crews:

- to review charts and have an appreciation of the major topographical features of all destination airfields.

- to review the relevant airfield features during approach briefing, and

- continually review all previously identified navigation aids, even in VMC to ensure correct identification of airfields.

The RAAF has ensured that all relevant airport facilities at Laverton adequately show that the airfield is decommissioned.

The pilot and four friends departed Bankstown on a visual flight rules (VFR) pleasure trip in the pilot's recently purchased Piper Cherokee Six (PA 32-260). The trip had been planned to take five days and included flight legs to Bourke, Birdsville, Alice Springs, Yulara, Oodnadatta, Broken Hill, Condobolin, Parkes, and thence to Bankstown.

The first leg to Bourke was uneventful. However, when the pilot refuelled following arrival at Birdsville, a heavy flow of fuel was observed from the overflow and vent of the left main fuel tank. The fuel system of this aircraft consists of four separate fuel tanks; left and right tip and mains. Fuel feeds to the engine from a single fuel tank at a time and depends on a manual selection by the pilot. The pilot concluded that the flow was coming from the left tip tank. He believed that the contents of the left tip tank were flowing into the left main tank. When he moved the fuel selector to the right main fuel tank, the leak quickly stopped.

Fuel was again observed flowing from the vent and overflow of the left main fuel tank whilst the aircraft was enroute to Alice Springs. The fuel system was subsequently inspected at Alice Springs by a Licensed Aircraft Maintenance Engineer (LAME). The LAME informed the pilot that the left tip tank should not be used but that the remaining three tanks were safe to operate. The pilot elected to complete the trip by filling only the remaining three fuel tanks, leaving the left tip tank empty. With the three tanks full, he calculated that the aircraft's endurance was reduced to 4 hours and 45 minutes. Further legs of the trip were uneventful. The pilot calculated that the average fuel consumption remained at approximately 55 L/hr.

The pilot's fuel management technique for the remaining three tanks was to operate from the right main fuel tank from take-off until reaching cruise level, a period of approximately 10 minutes. He would then select the right tip tank and draw fuel from this tank for approximately 50 minutes. The left main fuel tank was then selected and would be drawn from for about 30 minutes. This would be followed by the right main fuel tank for a further 30 minutes, and so on, in order to maintain the aircraft's lateral balance.

On the day of the incident, the pilot had planned to fly from Oodnadatta to Condobolin via Broken Hill, with a possible extension to Parkes depending on in-flight calculations of fuel remaining. The pilot had started preparations for this leg shortly after dawn. Following a refuelling stop at Broken Hill, the aircraft departed at 1422 EST for Condobolin. When the aircraft reached Menindee at an altitude of 5,000 ft, a significant amount of cloud was observed along the planned track. A diversion was made to the south and the aircraft was descended to maintain altitudes between 2,000 ft and 3,000 ft. With the weather to the north still looking unsuitable for continued VFR flight, the pilot elected to divert for a landing at Griffith.

Greater than expected headwinds were encountered on the track to Griffith with the aircraft's groundspeed reducing from 90 kts, the planned groundspeed for the Broken Hill to Condobolin leg, down to as low as 75 kts. However, the pilot believed that he had more than sufficient fuel to reach Griffith. He became concerned about the fuel state when the aircraft was some 20 NM north-west of Griffith. He subsequently transmitted a message on the flight service frequency indicating that he may need to consider a landing before reaching Griffith. An alert phase was declared and crews of aircraft in the locality were asked to provide assistance in guiding the pilot to Griffith in the failing light conditions.

The pilot reported that the engine started to falter when the aircraft was approximately 10 minutes flight time from Griffith. He had been drawing fuel from the right tip tank and responded quickly by changing the fuel selector to the left main fuel tank. The pilot was verbally assisted to locate the lights of the aerodrome by the crews of two aircraft in the area. At the top of the descent for landing, the engine started to falter again so the pilot selected the right main fuel tank. Whilst on final approach, the engine again started to falter, however, the pilot was concentrating on the landing and chose not to make another fuel tank selection. A safe landing was completed at 1820, however the engine stopped during the ground roll and the aircraft had to be pushed clear of the runway. The total elapsed flight time from Broken Hill was 3 hours and 58 minutes.

The aircraft underwent inspection by a LAME at Griffith following the incident. No anomalies could be found with the fuel system, fuel gauges or the engine, which may have contributed to the incident. No explanation could be found for the fuel overflow problems which had been experienced earlier in the trip.

The pilot held a valid licence and medical certificate for the operation being undertaken. He had accumulated a total of approximately 750 hours and had flown about 50 hours in a similar Cherokee Six previously. Whilst he held a Night VFR rating, he did not satisfy the recency requirements in order to exercise the privileges of that rating. However, this was not considered to be a contributing factor to the incident.

The pilot had recently purchased the PA 32-260 after completing a 40-minute inspection flight at Roma with the previous owner. He later ferried the aircraft from Bathurst to Bankstown, a flight of approximately 1 hour and 20 minutes. In addition, he had completed a half hour period of circuits before embarking on the pleasure trip. He had amassed some 25 hours in the aircraft during the trip, culminating in the incident flight.

On reflection, the pilot believed that the incident resulted from a number of contributing factors. The incident flight was flown at much lower altitudes than those of the previous legs of the journey, most of which had been flown at approximately 7,500 ft. The pilot reported that he continued to use a high-power setting of 2,450 RPM and a slightly richer mixture to maintain smooth operation of the engine. In addition, the aircraft was not fitted with an Exhaust Gas Temperature or Cylinder Head Temperature gauge to assist with accurate leaning techniques. The resultant effect would have been a higher fuel consumption than he had previously experienced. Discussions with other pilots and maintenance personnel who were familiar with the aircraft type, considered that a fuel consumption rate of 60 L/hr was a more accurate reflection of the aircraft type's average fuel consumption. Using this fuel consumption figure and fuel capacities gleaned from the aircraft's flight manual, the fuel endurance of the aircraft, with the remaining three tanks, was calculated to be approximately 4 hrs and 10 minutes. When a fuel consumption rate of 55 L/hr was substituted, the aircraft's endurance was approximately 4 hours and 33 minutes, still 12 minutes less than the pilot had calculated.

The pilot added that a passenger had to return to Sydney to enable him to connect with a flight to Perth. This self-imposed pressure influenced his decision to "push on". These two factors, combined with the cumulative effects of fatigue resulting from a five day journey, the last day of which had commenced at dawn, most likely eroded his ability to make sound decisions and judgements, in what became stressful circumstances.

Shortly after take-off, the crew of the Boeing 767 were advised by ATC that tyre debris and part of a control pulley had been found on the departure runway. The crew advised that they would return to land after jettisoning fuel to reach maximum landing weight. The crew later declared an emergency due to aircraft control difficulties. A distress phase was initiated by ATC. When emergency services were in position, the airport was closed to all other operations and the aircraft landed safely.

A subsequent inspection of the aircraft revealed that the tread of the inner rear tyre on the right main landing gear had separated, although the tyre had remained inflated. Liberated rubber debris had entered the right wheel well, damaging a pulley and its mounting bracket in the right inboard aileron control system. This led to a loss of function of the right inboard aileron due to a reduction of aileron cable tension.

Investigation of the tyre failure by the tyre manufacturer concluded that the failure was the result of the loss of rubber adhesion to the casing plies below the buff line. The tyre was on its fifth retread and had been subjected to nine landings since the last retread.

The aircraft manufacturer reported that redundancies built into the aircraft control system provided sufficient remaining lateral control, despite the loss of right inboard aileron function.

Once established in the cruise, the pilot noticed that the right auxiliary fuel gauge indicated an above average consumption. When the fuel selector was changed to right main tank, the excessive consumption remained. The pilot decide to continue to destination after calculating his endurance at the indicated fuel consumption. At this stage the aircraft had passed the equal time point. He cross-fed fuel from the left-wing fuel tanks and kept both engines running. The aircraft arrived with 120 litres of fuel on board.

A post flight inspection by maintenance staff found that the right wing was stained underneath with avgas. Further investigation found that the fuel delivery hose to the fuel control unit was under torqued. Removal of the fuel finger filter found that the adapter O-ring was damaged.