The Sector 15W controller became busy with a number of aircraft and subsequent co-ordination and did not pass the radar identification of a northbound B737, on climb to flight level (FL) 330, as the aircraft approached

Williamtown airspace. The Sector 15W controller was also briefing another controller with the intention of opening the planner position. The APPR controller contacted the Sector 15W controller and requested departure instructions for an aircraft at Williamtown about to depart via Sector 15W airspace. While the two controllers were discussing the availability of departure instructions for this aircraft, the APPR controller observed an unidentified aircraft overhead Williamtown and requested details from the Sector 15W controller. The Sector 15W controller advised that the aircraft was a B737 at flight level (FL) 330 tracking direct to a position near Coolangatta.

The APPR controller considered there had been a breakdown in procedures but did not discuss the perceived breakdown with the Sector 15W controller. The Sector 15W controller believed he was operating in accordance with the co-ordinated arrangements and continued at the position until the completion of the shift. There was no breakdown in separation.

ANALYSIS

The APPR controller could have used a number of specific terms to grant approval for the transit of Sector 15W's aircraft through military airspace. Any of these terms would have explicitly indicated the status of the approval. The Sector 15W controller could have been more vigilant when he accepted the offer of the use of the airspace. Possibly, in his haste to utilise the airspace he did not appreciate the ambiguity of the phraseology.

The use of imprecise and ambiguous co-ordination phraseology enabled a situation to develop which could have had more serious consequences.

SIGNIFICANT FACTORS

1. Neither controller considered the ambiguous aspects of the non-standard co-ordination phraseology.
2. The Sector 15W controller did not pass the radar identification of the B737 to the APPR controller in a timely manner.

The SAAB 340B aircraft was conducting a regular public transport flight from Wagga to Sydney via the Bindook VOR navigation aid. The crew had been told by ATC to expect an OAKDALE 2 arrival into Sydney. Approaching Bindook the SAAB was instructed by ATC to enter the holding pattern at FL170.

The captain removed his headset to advise the passengers on the public address (PA) system of the delay, whilst the first officer handled the aircraft. Shortly after, as the captain was addressing the passengers, ATC cancelled the holding and instructed the SAAB to turn onto a heading of 180 degrees, on descent to FL160. The first officer acknowledged the cancellation of the holding, and the descent clearance, but did not readback the assigned heading.

When the captain had completed the PA announcement the first officer advised him that they had been cleared to leave the holding pattern and track direct to the Bindook VOR for an OAKDALE 2 arrival. The captain was unaware that the aircraft had been assigned a heading.

ATC noticed the SAAB turning left through its assigned heading and queried the crew, reiterating the required heading of 180. As the SAAB turned right to 180 degrees, the separation between the SAAB and a British Aerospace 146 (BAe 146) was reduced to 3.5 NM laterally and 500 ft vertically. The SAAB passed behind the BAe 146 as ATC issued instructions to the aircraft to increase their vertical separation. The minimum required separation standard was 5 NM horizontal, or 1,000 ft vertical.

The expectation of an OAKDALE 2 arrival may have caused the SAAB's first officer to anticipate a standard intercept from the Bindook aid. This error could have been averted if ATC had queried the lack of the assigned heading readback by the first officer, and if the captain's attention had not been diverted by making a PA announcement. The captain reported that PA announcements are usually made at the commencement of holding, to minimise any conflict with normal ATC communications. However, he had not anticipated that the holding would be cancelled so quickly, and consequently had not heard the ATC instructions.

1. Reversal of the flight levels of the two eastbound aircraft.  That is, giving the actual flight level of the first aircraft as that of the second aircraft.  If this was the case, the aircraft in the B747 crew's 1 o'clock would have been at FL 250 as reported by them.
2. Reversal of the clock code position.  Where the 1 o'clock position was transposed with the 11 o'clock position. This may have been related to the mental inversion of the radar screen image required to be performed by the controller to give relevant information to the crew of the B747.  The view of the radar screen is north facing, whereas the B747 was heading south and separation had already been achieved between it and the aircraft below. The controller had ensured separation with the aircraft above by requiring the B747 to level out at FL 280.  Giving traffic on this aircraft was a safety measure to assist the B747 crew's situational awareness.

There also appeared to be a misunderstanding of the request from the B747 crew as to clearance to the next waypoint. The controller cleared the B747 to TAPOP when the request was direct to TAXON. This misunderstanding was not considered relevant to this occurrence.

The TCAS display reported by the captain of the B747 was due to the type of TCAS on the aircraft. TCAS II with a 604 software update will display a proximity target if the target is currently within 6 NM and 1,200 ft of the TCAS aircraft.  There was no traffic advisory given by TCAS, but the aircraft was displayed on the screen due to this sensitivity.

SIGNIFICANT FACTOR

Incorrect traffic information was passed to the crew of the B747.

The Inner North sector controller became distracted with a number of tasks at the position and with other aircraft in the sector and forgot to pass the radar identification of the B737 to the next control position; Departures South. The transfer of aircraft radar identification between the two positions is normally conducted between 35 NM and 40 NM from the aerodrome. This ensures that the next controller is aware of the position of inbound aircraft and can plan the separation with traffic in his sector prior to the aircraft entering the area.

At the time, the Flow controller had not annotated the flight progress strip (FPS) for the inbound B737 with a landing time. The FPS was located adjacent to the Departures South position to enable controllers to appreciate the sequence of arriving aircraft. The Flow controller handed over responsibility to another controller. The new Flow controller observed the inbound B737 on the radar display but did not annotate the FPS with a landing time.

The inbound B737 was maintaining 8,000 ft and was 20 NM from the aerodrome. The Inner North controller noticed that he had not transferred the inbound B737 and instructed the crew to call Departures South. The Inner North controller then electronically transferred the identification of the aircraft to the Departures South position. This was contrary to air traffic control procedures. The controller transferring responsibility for an aircraft must receive notification of acceptance of the aircraft, either by voice or electronically, from the controller receiving the aircraft prior to instructing the aircraft to call. The Inner North controller did not advise the Departures South controller of the late transfer of the radar identification and transfer of the inbound B737.

The Departures South controller was busy with other aircraft in the sector and monitoring the departure of a B737 on a Cowes standard instrument departure (SID) from runway 27. This aircraft had been initially assigned climb to 5,000 ft. The Departures South controller did not observe the inbound B737 within his area of responsibility and approved the outbound B737 to climb to flight level (FL) 200. When the crew of the inbound B737 contacted Departures South, the controller recognised the potential conflict and instructed the outbound B737 to maintain 7,000 ft. The crew of the outbound B737 were unable to arrest the rate of ascent until the aircraft had reached 7,600 ft. The Departures South controller issued traffic information to the crew of the inbound B737 about the other aircraft. The crew were able to observe the outbound B737 and maintain visual separation until radar separation was regained.

The two aircraft passed with vertical separation of 400 ft and horizontal separation of 2 NM. The separation required was 1,000 ft vertically or 3 NM horizontally. There was a breakdown in separation.

ANALYSIS

The Inner North controller became distracted with other aircraft in his sector and did not transfer the identification of the inbound B737 to the Departures South controller as required by local instructions. Consequently, the Departures South controller was not aware of the inbound B737 as the aircraft entered his sector.

The lack of a landing time on the flight progress strip was a missing cue that may have alerted the Departures South controller to the inbound B737. The reason for the landing time not being annotated on the flight progress strip could not be ascertained.

The Departures South controller did not observe the inbound B737 enter his airspace prior to instructing the outbound B737 to climb to FL200. Had he maintained a more regular scan of the display it is possible that he would have observed the inbound B737 entering his sector.

When the Inner North controller became aware that the inbound B737 had entered the Departures South sector without a transfer of the aircraft's identification, he should have contacted the controller on the intercom. This would have alerted the Departures South controller to the presence of the inbound B737 and may have enabled separation to be maintained between the two B737s

SIGNIFICANT FACTORS

1. The Inner North controller did not pass the radar identification to the Departures South controller prior to the inbound B737 entering the latter's airspace.
2. There was no landing time annotated on the flight progress strip for the inbound B737 for the Departures South controller.
3. The Departures South controller did not observe the inbound B737 entering his sector.
4. The Inner North controller transferred the inbound B737 to the Departures South controller prior to conducting radar co-ordination.

VH-ANP, inbound from the north was being processed for a runway 26 ILS approach to Essendon. VH-EAJ, also inbound from the north, was being processed for a runway 27 ILS approach to Melbourne. While tracking in an easterly direction, on a right downwind leg for the ILS approach, the pilot of ANP reported he had Essendon in sight. He then requested priority as a Med 1 flight for clearance direct to Essendon.

To facilitate separation with, and priority for, ANP, EAJ was instructed to climb to and maintain 4,000 ft. Shortly afterwards, when in the Epping area, and maintaining 4,000 ft, EAJ was instructed to turn right heading 310 deg for a vectored right orbit. At this time, ANP was to the east of EAJ, on a southerly heading, on descent to 2,500 ft, on a wide right base for runway 26 and with the mode C level indicating 3200 ft. There was a strong westerly wind blowing above 2,000 ft and this resulted EAJ making good a track of approximately 335 deg from a heading of 310 deg.

The two aircraft passed with less than three miles horizontal separation when vertical separation was 800 ft. The pilot of ANP had EAJ in sight.

After departure, the pilot reported that the landing gear did not retract normally and requested a low-level flypast for a visual inspection. Inspection from the ground revealed that the right main wheel was turned through 90 degrees. Emergency services were requested and when they were in position the pilot elected to land on the grass strip with the landing gear retracted. The aircraft sustained substantial damage during the subsequent landing but neither of the occupants were injured.

A subsequent inspection of the aircraft revealed that the right main landing gear torque link bolt had failed, and the torque links had separated. This allowed the main wheel assembly to rotate away from its normal position. The aircraft's maintenance records indicated that maintenance had recently been carried out on the right landing gear. The accident flight was the second flight following completion of that maintenance.

He initiated a practice forced landing and conducted the required checks. At about 2,800 ft he attempted to warm the engine but obtained no response. The throttle was retried, still without response. The emergency checks were carried out again and a Mayday call was transmitted. The pilot attempted to restart the engine using the starter.

With no engine response, the pilot continued with the forced landing. Two fields were selected, with the secondary field being beyond an earth bank at the far end of the desired field, as the pilot had been experiencing a tendency to overshoot during the earlier flights. Since no response was obtained from the engine, the engine shut down checks were completed prior to landing.

Witnesses reported that the engine note had not varied during the approach to land. There was no surging or back firing. The aircraft touched down at the end of the primary paddock and rolled some 18 m before colliding with the earth bank which was about 1.8 m high. The fire wall and rudder pedal areas were distorted by the impact.

Subsequent investigation involved analysis of a fuel sample from the aircraft and examination of a section of exhaust pipe from the engine. The fuel was within specifications, and the exhaust pipe temperature was below the detectable limit. Since an idling engine could also have exhibited temperatures below that limit, no conclusion concerning engine operation could be reached. An examination of the engine and its systems did not find any abnormalities which could have caused the problem. The Bureau of Meteorology reported that the air was very dry and there was no possibility of carburettor icing. No reason for the engine's failure to respond has been established.

The aircraft was not equipped with an emergency locator transmitter.

SIGNIFICANT FACTORS

1. The engine failed for reasons not determined.
2. The pilot had low total flying experience.
3. The pilot misjudged the approach to land.

At 1550 VH-RUH, enroute Broken Hill to Moorabbin, reported overhead Natya at 7,000 ft. At 1552 VH-LJR, enroute White Cliffs to Essendon, reported overhead Natya, also at 7,000 ft. The Flight Service (FS) 14 operator was expecting LJR to be at its planned level of 5,000 ft. Neither aircraft was aware of the other and traffic information was immediately passed.

Investigation revealed that the pilot of LJR requested traffic for a climb to 7000 ft 16 minutes after departure from White Cliffs. That request was to the FS15 operator. Nine minutes after that request the pilot of LJR reported maintaining 7,000 ft. Departure co-ordination from FS15 to FS14 was done manually because the operators were too busy on their frequencies to do it by intercom. The investigation was unable to determine whether the level change was co-ordinated as part of the departure co-ordination.

The pilot of LJR called FS14 at 1510 (42 minutes before he reported over Natya) and reported maintaining 7,000 ft and an amended estimate for Natya. The FS14 operator did not realise that LJR was no longer at its planned level and the FS14 flight strip still indicated 5,000 ft. When the aircraft later reported at Natya, there was a different operator working the FS14 position. He immediately noticed the aircraft was not at its planned level of 5,000 ft which was still annotated on the flight strip.

Both FS15 and FS14 were very busy at the time. FS15 was dual manned and in addition to normal traffic was handling a difficult distress phase which extended over a protracted period.

The pilot of VH-MVX was given a departure instruction to turn left onto a heading of 030 degrees and to maintain 2,000 ft. The departure was being made from runway 15. The pilot had planned to cruise at 9,000 ft. The restriction to 2,000 ft was due to an inbound jet on the 153 radial which had been assigned 3,000 ft and had been programmed for a left circuit for runway 15.

VH-MVX was cleared for take-off, and before the pilot contacted the departures frequency, the departures controller advised the tower that the jet would be now tracking for a right circuit. After sighting the inbound jet, the tower controller volunteered to separate the two aircraft.

On first contact with the departure’s controller, the pilot of VH-MVX reported on climb to 9,000 ft, the flight planned altitude. Since the separation problem had been resolved, the departures controller thought that the tower had cancelled the altitude restriction, and he accepted the altitude without comment.

The pilot of VH-MVX subsequently reported maintaining 3,000 ft. There was no restriction by this stage and the pilot was cleared to climb to 9,000 ft.

For this sector, the captain was the pilot flying (PF), and the copilot was the pilot not flying (PNF). The clearance instructions and restrictions were correctly received, understood, and readback by the crew. The assigned altitude 2,000 was placed in the assigned altitude indicator. This is to remind the crew of the last assigned altitude. After take-off, the PNF contacted departures in the normal manner. He reported climbing to the originally cleared and planned level of 9,000 ft. This incorrect level advice was not challenged by the approach controller. The PNF could not explain why he forgot the 2,000 ft restriction. The captain stated that he did not hear the copilot say 9,000, believing he said 2,000. The departure controller then requested the pilot accept amended tracking instructions. These were accepted, again without reference to the 2,000 ft restriction. Company Standard Operating Procedures (SOP's) require the PNF to refer to the assigned altitude indicator when reading back altitude clearances issued by air traffic control. The captain stated that he was happy to comply with the amended tracking instructions, was well aware of the restriction to 2,000 and was intending to comply with this restriction as well. He then subsequently climbed through the restricted altitude.

Company SOPs require the PF to initiate altitude calls at 1,000 ft and 500 ft to go to assigned levels and for the PNF to respond. These calls were not made, nor challenged.

The occurrence was allowed to develop through the failure of air traffic control and the crew to maintain adequate situational awareness. The safety net failed when the crew failed to comply with SOP's, cockpit management was inadequate, and the copilots support role was also inadequate. Action has been taken by the company to improve crew performance, and a notice issued to all pilots instructing them to apply extra vigilance to their duties.

The pilot advised that the weather was fine, water conditions calm, and the river running at 6 - 8kt. The aircraft was launched from the bank and taxied downstream for departure.

The pilot reported that the aircraft's acceleration, and climb onto the step appeared to be normal, but before the aircraft became established on the step it began to porpoise. He attempted to overcome the oscillations by applying forward elevator control pressure which only aggravated the situation. He then tried to find the optimum position on the step by raising and lowering the nose with the elevator control, resulting in him chasing the oscillations.

The aircraft eventually "wheelbarrowed" on its bow, preventing it from accelerating to its safe take-off speed. The pilot persisted with the take off, and while attempting to turn a bend in the river water pressure on the bow damaged the left nose gear door, creating an increase in water drag. This caused the aircraft to water loop to the left, damaging the left sponson and rear fuselage.

The pilot rejected the take off and taxied the aircraft to the shore.