The pilot reported that during cruise he experienced a loss of engine power associated with rough engine operation. He carried out a precautionary search and landed in a paddock. After landing, the engine was test run and could not be faulted. The pilot, having assessed that the available take-off length and surface conditions were adequate, elected to fly the aircraft from the paddock. The aircraft became airborne later than expected and struck a fence. A landing was made in the paddock immediately past the fence.

The crew of VH-NSD received an amended clearance on the flight from Townsville to Mackay, which required tracking over Proserpine. They experienced difficulties receiving the Proserpine VOR (VHF OMNI Range), in that the aircraft indications on both receivers were not indicating a steady reading. The pilots averaged the indications, but when they transferred to the Mackay VOR, they found that their aircraft was on the 300 degree radial and not the 311 degree radial as cleared by air traffic control.

The aircraft was then cleared to continue inbound on the 300 degree radial. Another aircraft was outbound on the 285 degree radial at the time and a breakdown in separation had occurred. The aircraft were estimated to have come within 8nm (15km) of each other.

The crew of VH-NSD did not report their inability to navigate accurately using the Proserpine VOR. This would have allowed air traffic control to use another means of separation other than confining the aircraft to radials. Mackay Air Traffic Control reported that the Proserpine VOR has not been reported as unserviceable by any other aircraft prior to or after this occurrence.

Two aircraft had departed runway 35, and VH-SLW had commenced a take-off. On reaching about 50 knots the pilot noticed the lights of VH-JMZ on final approach for runway 17 at about 200 feet above ground level. The pilot of VH-SLW stated that he expected the pilot of VH-JMZ to carry out a missed approach, and although his immediate reaction was to abort the take-off, he decided to continue as the aircraft was accelerating rapidly and going too fast to safely vacate the runway.

The pilot of VH-JMZ executed a short field landing and stopped short of the runway 08 intersection. VH-SLW became airborne and passed over the top of VH-JMZ at about 90 knots and 80 feet above the runway. The pilot of VH-JMZ acknowledged a taxiing call from VH-SLW when he was mid downwind for runway 17, but the pilot of VH-SLW did not hear this acknowledgement and was unaware of the presence of VH-JMZ. The second pilot in VH-SLW was not monitoring radio transmissions at the time.

The orientation of the aircraft prior to entering the runway was such that the pilots in VH-SLW were unable to see the downwind leg of runway 17 before they lined up. A review of the ATS tape recordings show that the pilot of VH-SLW did not make a radio transmission to advise traffic that he was lining up on runway 35 or that he was beginning his take-off roll. While on downwind for runway 17, the pilot of VH-JMZ had communicated with Cessna 210 VH-APU which was departing from runway 35, so that separation could be maintained with this aircraft. Once VH-APU was clear the pilot of VH-JMZ continued his approach, with the expectation that the runway would not be occupied

 After advising VH-SLW that he was mid downwind, the pilot of VH-JMZ did not transmit his position in the circuit. Just before landing he questioned the actions of the pilot of VH-SLW. The pilot of VH-JMZ reported that when he first saw VH-SLW on the runway he thought the aircraft was back-tracking and would vacate the runway but then realised that the aircraft was in fact taking off towards him. He believed that he was committed to land and could not carry out an overshoot once below 400 feet. He was aware that VH-SLW was occupying the runway when he landed.

Significant Factors

During the landing and take-off sequence of VH-JMZ and VH-SLW, the pilots placed their respective aircraft in a risk of collision situation.

Safety Action

Deficiencies identified during this investigation, including operational practices at uncontrolled aerodromes, are being analysed in conjunction with other occurrences in order to formulate appropriate safety actions.

The pilot requested, from Sydney Flight Service International, the NOTAM status of R674. The Flight Service Officer (FSO) checked the status using the FISOR system and advised that the area was not active. R674 is a military restricted area and is active on a 24-hour basis, any change to this status is advised by NOTAM. When the FSO checked the system, he received a message which indicated that there were no current NOTAMs for R674.

The correct interpretation of this message is that the area would still be active. Apparently the FSO, who was not familiar with the normal status of the restricted area, assumed that if no NOTAMs were current for the area, then it was not active. He should have advised the pilot that there were no current NOTAMs for R674. Significant factors 1. The Flight Service Officer made an incorrect interpretation of the message on the FISOR system.

Circumstances

The Arrivals North Controller [ARRN] had commenced duty at approximately 0705 EST and was experiencing a period of heavy air traffic. He had requested the previous occupant of the position to remain at the console in the monitor position to assist him in a settling-in period. This controller was in the monitor position during the events of this occurrence.

The FLOW controller had decided that he would request the use of Sector 8 airspace for three aircraft to reduce the workload on the arrivals controller and reduce the delay to the aircraft. The Sector 8 controller agreed to the request and raised the required flight progress strips [FPS] for his own reference. After receiving instructions from the FLOW controller to track both VH-TQO and VH-TQQ via Richmond, ARRN proceeded to process the two aircraft onto that track, a track that would take them clear of the main arrival route of Singleton to Sydney.

VH-TQO was proceeding at Flight Level [FL]190 on a flight from Tamworth to Sydney. At 0718 ARRN instructed VH-TQO to track direct to Richmond and thence to Sydney. This resulted in the aircraft tracking approximately 210 deg. VH-TQQ was proceeding at FL160 on a flight from Port Macquarie to Sydney and was on a similar track to that of VH-TQO and approximately 12NM behind. At 0721 ARRN instructed VH-TQQ to track direct to Richmond and thence Sydney.

This resulted in the aircraft tracking approximately 200 deg. At 0722 ARRN handed to Sector 8 the identification on VH-TQO with the assigned altitude of 8,000ft. This was accepted by Sector 8 who wrote this altitude on the FPS for VH-TQO. Both aircraft were then descended to 8,000ft by ARRN and at 0724 the controller, intending to transfer VH-TQO to Richmond Approach, mistakenly instructed VH-TQQ to contact Richmond Approach [Sector 8]. VH-TAF was on descent to FL200 on a flight from Coolangatta to Sydney and was tracking on the main arrival route from Singleton to Sydney.

At 0726 ARRN instructed VH-TAF to descend to 8,000ft. When VH-TQQ contacted Sector 8 the controller acknowledged with the callsign TQQ but notated the details on the FPS for VH-TQO. At 0726 the Sector 8 controller had a departure from Richmond that was conflicting with VH-TQO and elected to vector VH-TQO in order to maintain separation. He issued VH-TQQ, the aircraft on his frequency, with an instruction to turn left heading 140 for separation. The crew obeyed the instruction but were approximately 12 NM north of the point the controller thought the aircraft was passing.

The controller saw that VH-TQO was not turning and issued a further left turn to a heading of 120 to VH-TQQ. This placed VH-TQQ on a track that would conflict with VH-TAF. ARRN did not immediately realise that VH-TQQ had turned back towards the main Singleton to Sydney track and it was the arrivals controller in monitor who first saw the new position of VH-TQQ and initiated recovery action. At about the same time the crews of both VH-TQO and VH-TQQ started to question the control instructions and asked if there had been a transposition of the callsigns.

At 0728 ARRN instructed VH-TAF to turn left immediately onto a heading of 090 deg. to place that aircraft on a heading away from VH-TQQ. Flight levels were then checked and vertical separation established until radar separation could again be guaranteed. Radar analysis showed that there was no breakdown in separation as vertical separation existed at all times during which horizontal separation was not provided.

The callsigns were very similar and belonged to the same type of aircraft in the same company. Anecdotal evidence and statements from the persons concerned in this occurrence, indicate that this confusion has often arisen because of the common feature of these two aircraft being processed for arrival or departure at similar times. During the course of the interviews five controllers complained of the two callsigns being on frequency together and having had trouble with them at some time or other.

The crew of VH-TQQ were expecting to be given the radio frequency change to Richmond Approach at the time the ARRN controller issued the instruction and, therefore, had no reason to query the instruction. The O and Q do not readily stand out from one another on the digital read out of the radar display and this can lead to a confusion of callsigns in high density traffic situations.

Significant Factors

1. The callsigns TQO and TQQ are very similar and do not stand out from each other on the digital read out showing on the radar screen.

2. VH-TQO and VH-TQQ were given the same tracking instructions while proceeding 12 NM in trail.

3. Both the Arrivals North controller and the Sector 8 controller used the callsign TQQ when intending their transmissions to be for TQO.

Safety Action

Since the above incident a further occurrence has been reported to the Bureau. On 23 March 1994 a controller at Sydney transposed the callsigns and issued a clearance to TQO which was intended for TQQ. On this occasion there was no further incident as the pilot queried the callsign immediately and corrective action was taken.

Recommendation

R930316

With the above occurrences in mind, the Bureau of Air Safety Investigation recommends that Qantas Airways: Change the registration of VH-TQQ to avoid confusion with other callsigns.

About 5 minutes after take off the engine began to run roughly. The aircraft returned to Hoxton Park and after landing the pilot found the fuel strainer full of water. The aircraft had been refuelled about 10 days before from a ground installation and had remained in the open since then. Investigation revealed that no other operators who had refuelled from the same installation had suffered from water contamination. The fuel installation is a modern style appliance with a water sensing element which automatically shuts itself down if water is detected.

It was not determined how the water got into the fuel system but there had been periods of heavy rainfall whilst the aircraft had remained in the open and it is possible that water had leaked in through the fuel caps.

The aircraft lost power shortly after take-off. A successful forced landing was made in a field adjacent to the strip. An inspection of the aircraft disclosed that a hose directing cooling air to the fuel injector manifold was kinked restricting the amount of cooling air available at the manifold. It is suspected that the manifold overheated and vapourised the fuel causing the loss of power experienced by the pilot.

The nose landing gear collapsed during the take off roll causing both propellers to strike the runway whilst operating at full power. Subsequent investigation revealed that a rigid hydraulic line had failed causing the loss of all hydraulic pressure. This lack of hydraulic pressure probably allowed vibrations to unlock the nose leg over-centre lock during the take off roll.

Examination of the failed hydraulic line revealed that there was thinning of the pipe wall at the failure where the pipe was supported by a 'P' clamp, possibly the result of corrosion. Significant Factors: Failure of a hydraulic pressure pipe, possibly due to corrosion, resulted in loss of all hydraulic pressure. The nose landing gear over-centre lock probably unlocked due to vibration.

The pilot of VH-TQL reported that when on short final for runway 12 the crew noticed a displaced threshold for runway 30 and men and vehicles commencing to enter the closed off area. No NOTAM for this activity was current and this was confirmed by the AVFAX help phone number. The RAAF advised that there had been a self cancelling NOTAM for work on the cable-hook arrester system on the previous day, and the work continued the next day but relevant authorities were not advised. Upon ascertaining that the work was continuing, the tower controller had immediately arranged for a Sydney NOTAM to be raised but it was not issued prior to the arrival of VH-TQL. Measures have been taken by the RAAF to prevent a recurrence.

After departing Canberra from runway 35 at 0744, the aircraft was observed by radar to correctly follow the assigned standard instrument departure. However, the pilot failed to transmit a departure report on departures frequency 125.9 and contact could not be established on tower, departures, approach or sector frequencies. At 0749 an uncertainty phase was declared. The aircraft was observed to be following the cleared route, Canberra to Bindook via Cullerin and at 0756, the pilot contacted Sydney arrivals and requested descent.

The uncertainty phase was then cancelled by Sydney Control. The crew of VH-TJO were interviewed by the company training manager, and although the captain could not specifically recall contacting Canberra Departures, it appears that the Sydney FIS frequency 125.7 MHz was incorrectly selected in lieu of 125.9 mhz. When a descent clearance was requested Sydney FIS directed the crew to the correct frequency.