Breakdown of co-ordination

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Port Moresby ATC passed coordination to Brisbane Centre on ANA923 and QFA 114 but the flight levels coordinated were incorrect. ANA 923 was coordinated at flight level 390 and QFA114 at flight level 370. At 1700, the pilot of ANA923 reported at VIPAM at flight level 370. When this was passed to Brisbane sector 11, confirmation of the flight level was requested, and this was confirmed by the pilot. Sector 11 contacted Port Moresby by telephone, and Port Moresby confirmed flight level 390.

At approximately 1710, Port Moresby called back to apologise and advise that the level coordinated should have been flight level 370, and QFA 114 should have been flight level 390.

An Airbus A320 taxied at Adelaide and the crew requested an airways clearance to Brisbane. Air traffic control issued the crew with a clearance to Brisbane via UVUPU (064 AD VOR 181NM) and planned route to cruise at FL370 with a runway 23 RADAR 3 departure. This clearance was correctly read back by the crew. However, the departures flight progress strip (FPS) for this flight had been incorrectly annotated with an UVUPU 2 standard instrument departure (SID) instead of a standard radar departure (SRD) RADAR 3.

When the crew reported ready for take-off the approach east (APPE) radar controller issued an "unrestricted" instruction to the aerodrome controller (ADC). The ADC cleared the aircraft for take-off without assigning a radar heading. The flight crew did not query this instruction and the A320 became airborne, the crew electing to maintain runway heading. The crew contacted APPE and reported "tracking runway heading, climbing to FL370 left 2,800". They requested approval to track direct to UVUPU which was approved by the controller. Believing the aircraft to be tracking via the SID, a discussion between the pilot and APPE then revealed that the pilot understood that he had been cleared on a RADAR 3 Departure, while the controller understood that the aircraft was tracking via the UVUPU 2 SID.

There were no traffic conflictions. The investigation revealed that there were two contributing factors in this occurrence. The aircraft callsign had been changed on the FPS and the APPE controller was concerned that the SSR code on the strip may have been entered incorrectly. While confirming this detail he was distracted and annotated the FPS with an incorrect clearance. The technique of writing the clearance on the FPS prior to the issuance was considered a significant factor. The controller had already written UVUPU 2 on the FPS and when he was distracted during the issuing of the clearance, he had made an incorrect assumption, which had been influenced by the clearance already written on the FPS. The pilot in command had been issued with a standard radar departure clearance which required an assigned heading to be issued by the ADC with the take-off clearance. When the crew received the take-off clearance without the assigned heading, they should have immediately queried the instruction.

However, they elected to take-off and maintain runway heading. This action was consistent with the SID procedure. On first contact with APPE, the crew did not specifically mention that they did not have a heading to fly, and the controller incorrectly assumed that they were departing on a SID, in accordance with the annotation on the FPS. There were explicit instructions in the Aeronautical Information Publication, which detailed the requirements to be followed when departing on a SRD. The controller was required to assign a heading prior to issuing the take-off clearance and the pilot was required to read-back that heading. Considering that air traffic control had two clearances current for the departure, the last safety defence was the assigned heading in the standard radar departure. Had the crew queried that no heading had been assigned for their departure, APPE would have immediately queried the requirement

The aircraft was incorrectly co-ordinated whilst transiting Amberley military CTR. Amberley ATC are required to co-ordinate an estimate for Brisbane for traffic transiting their airspace for landing at Brisbane. The pilot is then assigned a standard transfer level of 4,000 ft. prior to his transfer to Brisbane approach.

The first co-ordination from Amberley in this case, was an attempt to handoff FIS to Brisbane departures when the aircraft was west of Amberley at flight level 150. The departures controller accepted the aircraft to avoid delays. The aircraft continued on an east/ south-easterly heading from Amberley and entered approach south's airspace without co-ordination from Amberley. The pilot eventually contacted departures, and was turned back into the departure controller's airspace for processing for a right circuit on runway 19. There was no breakdown in separation.

Summary: The pilot had submitted a flight plan for the IFR flight at 7,000 ft. The aircraft was limited to 6,000 ft on departure, and this altitude, along with the departure time and the transponder code were mentioned in the co-ordination between the tower and sector controllers. The details read back by the sector controller included 7,000 ft as the altitude. This error was not detected by the tower controller. The pilot subsequently reported maintaining 6,000 ft when contacting the sector controller.

At no time was the altitude prefixed by "amended" or any such phrase to draw attention to the different altitude. Airservices Australia advice was that there is no requirement for the use of the term "amended" when the cleared level is different from the planned level. This incident is the subject of safety deficiency action to investigate the need for the use of the term "amended".

A Dash 8 had departed Sydney for Port Macquarie NSW. The crew was maintaining the aircraft at flight level 170 and reported that they were ready for descent. The sector 15 C controller issued instructions for the aircraft to leave controlled airspace on descent and for the crew to contact flight service for the portion of the flight to be conducted outside controlled airspace.

The boundary of controlled airspace was 12,500 ft and the crew contacted FIS 5 prior to that level. The flight service officer received the transmission but had not had any coordination on the flight from sector 15 C. Fortunately, there were no immediate traffic conflictions, and the flight service officer had time to peruse his flight strips and pass relevant traffic information to the crew of the Dash 8.

The sector 15 C controller, who was under training, had not passed the flight details regarding the Dash 8 to FIS 5. However, a tick had been placed on the flight progress strip indicating that the coordination had been completed.

While the Dash 8 had been en-route, the military airspace under the control of Williamtown air traffic control became active and this action required coordination between sector 15 C and Williamtown control, which included information on the Dash 8. This activity resulted in a short-term, high workload situation involving several conversations with Williamtown air traffic control.

At approximately the same time, a second training officer prepared to take over the training responsibilities from the original training officer. This handover/takeover took place at the console with both officers "plugged in" to the monitor jacks. This had the effect of the second training officer being unable to hear anything through his headset until the first officer removed his headset from the jack.

The crew of the Dash 8 received their instruction to contact flight service immediately after the first training officer unplugged from the console and he did not hear this transmission. The second training officer looked at the flight progress strip as the instruction was being given and, seeing that the strip notation indicated that the coordination had been completed, believed all appropriate action had been taken.

Neither the first training officer nor the trainee could remember when or why the notation was made on the flight progress strip indicating the completion of the coordination with FIS 5 but, on reflection after the occurrence, the training officer remembered that it had not been done.

There was no breakdown in separation.

Amberley airspace was de-activated during the previous night and was to become active for military operations at 0800 local time. At 0747 a controller at Amberley co-ordinated the activation with the Brisbane Approach Planner. The planner informed the radar operators and set the planner console to show pending status. The co-ordination was conducted by Amberley with the Sector 4 controller shortly afterwards. Between 0755 and 0815 the person filling the planner position changed on two occasions. The Brisbane Terminal Airspace Co-ordinator (TAC) had been expecting the Amberley airspace activation but had been in a conference during this time.

At 0815, the current planner received co-ordination on the departure of VH-NJW. The planner conducted the appropriate co-ordination with the Sector 4 controller. None of the radar maps were showing the Amberley airspace as active at this time. NJW subsequently departed and was transferred to the Sector 4 frequency. The Sector 4 controller had not queried the transfer as Amberley radar had been unserviceable, and the controller assumed that the alternative had been to direct the aircraft to Sector 4. Amberley Approach later enquired as to whether the Sector 4 controller had a radar return in the area about 50 NM west of Brisbane. The approach controller was informed that the aircraft was VH-NJW. There was no breakdown in aircraft separation.

An investigation by Airservices Australia found that the TAC position was not occupied at the time of the airspace activation. In addition, the quick changes of staff in the planner position resulted in the loss of the information to the later staff. The activation times were routinely co-ordinated between Amberley Approach and the Brisbane planner position. This was considered the most appropriate method. The investigation found that the planner had not ensured that the radar maps were set correctly at 0800.

Procedures were changed to log the Amberley airspace activation and de-activation times in the Airways Operations Journal. Annotations confirming that the radar consoles had been set correctly were also to be entered.

Report not released due to no IP comment from the Indonesian agency on this joint investigation report. ASOR hard copy held on occurrence file. Report not to be released without the approval of the Director or a DD Signed Alan L Stray Deputy Director Investigations 6 July 1998

FACTUAL INFORMATION

An international B747 was enroute from Singapore to Melbourne over northwestern Australia at flight level (FL) 350. The B747 was under the control of a Brisbane sector controller using procedural control. The Brisbane controller was a team leader and he had commenced work at 2300 EST. He conducted a performance check on another controller until 0200 at which time the other controller left the console for a break. The team leader continued operating the position for approximately another two hours. The team leader felt well except for a minor cold condition which had developed that afternoon.

Generally, the work at the sector, on the evening shift, could be divided into approximately three periods. The first period was from 2300 until 0100 and this was the time when departure and position reports for aircraft intending to transit the sector were mainly received from northern air traffic control centres. The period from 0100 until 0200 was when the boundary positions were received. The last period from 0200 to 0400 was when the aircraft actually entered the sector and the crews contacted the sector controller. On the day of the incident the last period had finished at approximately 0300.

The B747 had been cleared to operate at FL350 and the crew had requested a preferred level of FL370 after 0320. The crew of the B747 reported their position at Curtin at FL350 and with an estimate for PAVKO of 0336. The team leader co-ordinated the position report with a Melbourne sector controller. PAVKO was the point at which control of the aircraft would be transferred from Brisbane to Melbourne air traffic control. The team leader intended to approve the crew of the B747 to climb to the higher level and to co-ordinate the level as FL 370 with the Melbourne controller. However, the team leader co-ordinated the level as FL350. The Melbourne controller incorrectly readback the level as FL370. Neither controller noticed the incorrect readback of the level. The Melbourne sector flight progress strip for the B747 indicated the aircraft was at FL350.

The team leader asked the crew of the B747 if they would be requesting climb to FL370. The crew replied that they would shortly like to climb to the higher level. The team leader instructed the crew of the B747 to climb to FL370 with a requirement to reach that level by PAVKO. The crew reported to the team leader when the aircraft left FL350 on climb to FL370. Normally, an aircraft's change of level is co-ordinated with the next air traffic control agency. The team leader, however, thought he had previously co-ordinated the higher level with the Melbourne sector controller and consequently did not conduct any further co-ordination.

The team leader instructed the crew of the B747 to contact the Melbourne sector controller at PAVKO. When the aircraft reached PAVKO the crew of the B747 reported their position and level of FL370 to the Melbourne sector controller. The Melbourne sector controller had expected the aircraft to report at FL350. There had been an error in co-ordination.

ANALYSIS

The team leader may have relaxed after completing the busiest part of the shift. Additionally, the timing of the incident, the time spent at the position overall, the possible higher level of awareness required for the check and his minor cold, probably combined to the extent that his ability to concentrate adequately on the task was impaired to some degree.

The Melbourne controller may have had an expectation of the B747 being at FL370 due to previous experience and the fact that it is a standard level for aircraft flying a south-easterly route.

The relationship between the body's circadian rhythm and performance is well known. In this incident, the fact that both controllers were working during the early morning and were also approximately halfway through their shifts would probably account for their lack of concentration and the consequent mishandling of the co-ordination.

The team leaders mind-set relating to his intention to approve the crew of the B747 to climb to FL370 would have pre-disposed him to hearing what he expected to hear from the Melbourne controller. This is despite the fact that the team leader co-ordinated the correct level at the time.

SIGNIFICANT FACTORS

1. The team leader had been continuously operating the position for approximately four hours.

2. The incident occurred at a time of the day when errors in human performance are more likely.

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.