ANSP info/procedural error

1. The Chieftain pilot was unfamiliar with the airspace in the area.

2. The Chieftain pilot did not plan via the preferred route.

3. The Chieftain pilot was not provided with traffic information on the Dash 8 by air traffic control.

4. The proximity of the Taree CTAF to the Williamtown restricted area increased the complexity for operations in the area.

5. The controller did not appreciate the potential for conflict when the Chieftain pilot reported tracking direct to Williamtown.

6. The use of TCAS by the Dash 8 pilot and adherence to CTAF procedures by both pilots to locate and avoid the other aircraft.

The controller assumed that adequate separation would be achieved based on his experience. However, that left little margin to recover the situation after he saw the Chieftain on radar, tracking to Williamtown. The provision of traffic information would have probably enabled the Chieftain pilot to take action earlier to avoid the Dash 8.

The Chieftain pilot did not flight plan via the recommended track for aircraft operating from Taree to Sydney. Had he planned via NICLA it is unlikely that he would have entered the restricted area without a clearance. It would have also minimised the possibility of conflict with aircraft on the Williamtown - Taree track, which was one of the intentions of the preferred track advice in the en route supplement. The non-use of the preferred track to Sydney and the pilot's unfamiliarity with waypoint NICLA were indicators of inadequate flight preparation.

The Chieftain pilot had little option but to depart Taree when he was unable to communicate with the controller. However, that meant the pilot would be busy with CTAF broadcasts and establishing contact with the controller during the initial stages of the flight. It is likely that the increased workload, and the need for him to find NICLA, caused the pilot to probably approach task saturation. That was indicated by the pilot not appreciating the illogical aspects of being advised, in the same radio transmission, to expect a clearance by the Williamtown - NICLA track and to avoid the restricted area. Had the pilot been less busy with the flight, or more familiar with the area, he probably would have requested the controller to confirm the track to be adopted.

The controller was also probably approaching task overload as he coordinated a clearance for the Chieftain with Williamtown air traffic control. That was likely the reason for the controller advising the pilot of the incorrect track. In addition, he missed the pilot's advice of tracking direct to Williamtown. Had the controller been less busy he would have probably appreciated the content of both his and the Chieftain pilot's transmissions and taken action to clarify the situation. That could have included either navigation assistance or the provision of traffic information to the pilot.

The proximity of the Taree CTAF to the Williamtown restricted area results in increased complexity for both controllers and pilots, especially when aircraft are operating between controlled and non-controlled airspace. In this occurrence the use of TCAS by the Dash 8 pilot, and adherence to CTAF procedures by both pilots assisted them to resolve the situation. The occurrence also highlighted the importance of effective planning for both controllers and pilots prior to commencing duty or undertaking flights respectively.

The pilot of a Piper Chieftain had planned an instrument flight rules (IFR) flight from Taree to Sydney via overhead Williamtown. After the aircraft became airborne, the pilot contacted the Myall sector controller. The controller told the pilot there was no other IFR traffic and that the Williamtown restricted areas were active. Shortly after, the controller told the pilot that clearance on the planned track was not available and to remain clear of the Williamtown restricted areas. The pilot was told to expect clearance via the Williamtown - NICLA track. However, the controller had intended to tell the Chieftain pilot to expect a clearance via the Taree - NICLA track. The track from Taree to NICLA is 237 degrees. The pilot did not query the controller regarding the amended route. He acknowledged the controller's transmission and then reported intercepting the 198 degree track from the Taree NDB navigation aid direct to Williamtown, on climb to 8,000 ft. The controller subsequently saw on his radar display that the Chieftain was 15 NM south of Taree at 5,000 ft, inside the Williamtown restricted area. The Chieftain was also approximately 3 NM to the north of a northbound IFR de Havilland Dash 8 that was on descent to Taree. The aircraft subsequently passed each other safely.

Pilots of aircraft on the ground at Taree can normally communicate via VHF radio with the Myall sector, which is located in the Brisbane air traffic control centre. The Chieftain pilot later reported that he had attempted, unsuccessfully, to contact the controller on the aircraft's VHF radio while taxiing. The investigation could not establish why the Chieftain pilot was unable to communicate with the controller. The Chieftain was not fitted with a high frequency radio.

When the pilot of a southbound flight reports taxiing at Taree, controllers normally issue a secondary surveillance radar (SSR) code and then coordinate a clearance for the flight with Williamtown air traffic control. A controller can then issue a clearance once the aircraft is identified on radar after departure. As communication was not established until the Chieftain was airborne the controller had to coordinate with Williamtown after the pilot reported departure.

Because radar coverage in the Taree area was not available below about 4,500 ft, controllers were required to pass traffic information to IFR aircraft on other IFR aircraft. The Dash 8 and the Chieftain flights were traffic for each other. The controller later reported that he expected to identify the Chieftain before the Dash 8 left the Williamtown restricted area. Also, he considered that the amended track for the Chieftain would have provided separation, as it diverged from the inbound track of the Dash 8. After the Chieftain pilot's departure report, the controller did not appreciate that the aircraft was tracking direct to Williamtown and was likely to conflict with the Dash 8 on the reciprocal track.

The preferred route between Taree and Sydney, as listed in the Aeronautical Information Publication en route supplement, was W238 to NICLA and Craven, a position 41 NM west-south-west of Taree. That route avoided the Williamtown restricted area. The Chieftain pilot was unfamiliar with waypoint NICLA and was attempting to locate its position on his chart as the aircraft climbed.

During the departure the Chieftain pilot made radio broadcasts in accordance with common traffic advisory frequency (CTAF) procedures. The CTAF is used for operations in non-controlled airspace and is not monitored by air traffic control. Immediately after departure, the pilot broadcast on the CTAF that the aircraft was tracking to the Mount Mcquoid VOR navigation aid, located 39 NM south-west of Williamtown. He also advised that the aircraft was on climb to 8,000 ft. Shortly after, he contacted the Dash 8 pilot in response to the latter's inbound CTAF broadcast. The Dash 8 pilot was advised by the Chieftain pilot that he was 6 NM south of Taree passing 4,100 ft and tracking direct to Williamtown. The Dash 8 pilot then queried the controller regarding the Chieftain's position. The controller confirmed the position of the Chieftain relative to the Dash 8. The Dash 8 pilot then returned to the CTAF and advised sighting the Chieftain. The Chieftain pilot reported to the Dash 8 pilot that he could see the Dash 8.

The Dash 8 pilot later reported that he had used controller and CTAF reports plus information from his aircraft's traffic alert and collision avoidance system (TCAS) to see the Chieftain. He estimated the aircraft passed with about 3 NM lateral displacement.

Both pilots reported that the controller's frequency was very busy with a lot of radio transmissions.

1. The Adelaide flight progress strip in the tower was misplaced on the airways clearance delivery console during the handover/takeover of the surface movement control/airways clearance delivery positions.
2. The coordinator did not review the flight progress strip to ensure the crew had been cleared before coordinating the Sydney flight data record for VH-HYY.
3. The absence of ticks on the Sydney flight progress strip did not alert controllers to the fact that a clearance may not have been read back or issued.

Although the annotated Adelaide flight progress strip was accidentally placed on the airways clearance delivery console during handover/takeover, there were at least two chances of detecting the error (at the coordinator and aerodrome control positions, for instance) before the aircraft departed. The controllers were supposed to ensure that the flight progress strip annotations reflected the current status of the flight. They should have ticked the clearance to show that it had been issued and read back. Perhaps the controllers assumed the strips were correct because they had been forwarded from at least one other position. Alternatively, the controllers at the positions may have been distracted while managing other aircraft or tasks.

Because air traffic controllers need accurate flight information, they have to continuously assess and confirm data from different sources. Even if crews provide the destination when asking for taxi clearance, mistakes can still happen if controllers do not scrutinise the information.

The Australian Advanced Air Traffic Control System (TAAATS) held two flight data records for VH-HYY, one from Melbourne to Adelaide and the other from Melbourne to Sydney. The crew were cleared to Adelaide but the Sydney flight data record was coordinated in TAAATS. After the aircraft departed, the controller saw that its radar track did not "couple" with the flight data record. This was achieved when the air traffic system linked an aircraft's secondary surveillance radar track with the flight data record assigned to that code. Separation standards were not infringed.

Airservices Australia found that, in anticipation of a busy departure period, the controller operating the combined surface movement control and airways clearance delivery positions noted clearance details on all pending flight progress strips. The controller cleared the crew of HYY for Adelaide and ticked the clearance and altitude annotations on the strip after receiving a correct read-back. This was required to confirm that the clearance had been issued and read back correctly. After the surface movement control and airways clearance delivery positions were individually activated, and during handover/takeover, the Adelaide strip for HYY was accidentally placed on the airways clearance delivery console and the Sydney strip placed on the surface movement control console. When the crew sought a taxi clearance, the surface movement controller did not notice that the clearance annotated on the Sydney strip was unticked but still activated the strip. The strip was then passed to the coordinator position and the controller there changed the state of the HYY flight data record in preparation for the aircraft's departure. The coordinator processed the first observed record for that aircraft and did not notice that the clearance had not been ticked. The departure controller then received a system "preactive" electronic strip showing that HYY was taxiing for a departure to Sydney. The strip in the tower was then passed to the aerodrome control position. Neither of the two controllers staffing that position noticed that the clearance on the HYY strip had not been ticked. Controllers at each operating position were required to maintain and arrange their strips.

Because TAAATS gave a separate secondary surveillance radar code to each flight data record in the system, the Adelaide and Sydney flight data records for HYY had different codes. The HYY crew were later cleared for take-off and after departure, the Sydney flight data record did not link to the aircraft's radar track. After confirming that the aircraft track displayed on the radar was that of HYY, the departure controller told the crew to select the aircraft's transponder on the secondary surveillance radar code assigned to the Sydney flight data record. The track then linked to the flight data record and the electronic strip on the departure controller's display changed to active. Shortly after, the departure controller gave an amended clearance to the crew of HYY for direct tracking to Sydney. The crew replied that the flight was to Adelaide.

The Aeronautical Information Publication AIP GEN 3.4-36-38 gives the radiotelephony phraseology required around an aerodrome. When pilots seek a clearance and clearance delivery is in operation, they must provide the aircraft's flight number and the aerodrome where they first plan to land. When they seek a clearance to taxi, they may include this aerodrome if they wish. The automatic voice recording confirmed that the HYY crew had supplied their destination when seeking a clearance but that they did not include it when asking for a taxi clearance. In other words, they had complied with the AIP radiotelephony phraseology procedures.

1. The flight service officer did not provide directed traffic information to the crew of VH-XDZ about the disposition of VH-XDA.
2. The workstation design complicated traffic management, the maintenance of an accurate air picture, and oversight of the flight service officer's workload.
3. The absence of three staff on sick leave.
4. Management of the flight service officer was inadequate by allowing the officer to continue working for long periods, with a high workload, without satisfactory supervision.
5. Management of the flight service centre roster did not provide properly endorsed and rested staff to provide an effective flight service function

The incident occurred during a high workload period for the flight service officer. Analysis of the audio transmissions revealed frequency congestion, with multiple calls from aircraft and associated inter-unit coordination. The officer may have been suffering the effects of fatigue having worked unexpected periods of overtime on the preceding days, as well as concern stemming from the meeting held earlier during the day. The imminent closure of the flight service function had lessened motivation and morale and heightened general levels of uncertainty and anxiety. The detrimental impact of excessive anxiety, stress and high workloads on human performance has been well documented. These factors appear to have had a significantly adverse influence on the flight service officer's ability to perform effectively.

The console needed a large chart display on a mobile trolley placed at 90 degrees to the operating position to complement the overhead map display. The arrangement of this workstation was ergonomically undesirable, requiring the flight service officer to continually change physical position to correlate the flight progress strip display with the chart display. Moreover, the chart display was a physical barrier between the operating position and the supervisor/utility position. This barrier may have prevented the evening shift officer from noting the flight service officer's increasing workload.

The number of active flight progress strips for aircraft movements within the flight service officer's area of responsibility was considerable. Because the geographical display bays were not used and the strips were sequenced in chronological order, this adversely affected the situational awareness on the flight service officer

1. The pilot of one aircraft did not report taxiing at Mitton Creek to the FS1 officer.
2. VHF radio coverage did not extend to the Mitton Creek airfield.
3. HF radio operation was intermittent on the morning of the occurrence.
4. The large number of flights being managed on retransmitted frequencies by the FS1 officer made radio communication difficult.
5. The delay in the transmission of the departure reports by three of the aircraft limited the ability of the FS1 officer and pilots to fully appreciate the amount of aircraft traffic in the area.

Had the pilots of all the departing aircraft persisted with attempts to report taxiing at Mitton Creek to the FS1 officer it is probable that they would have received the necessary traffic information. While this would have delayed some flights, it would have ensured that the required traffic information was received by pilots prior to departure. While two pilots were able to have their taxi report relayed through the pilot of airborne aircraft, there was no confirmation that they had received the required traffic information.

The complexity of the traffic and the number of pilots operating on the FS1 frequencies made it difficult for the officer to communicate the required traffic information to pilots. The ability to transfer the retransmitted frequency to another operating position within the flight service centre would have reduced the number of radio communications being received/transmitted by FS1. This would have assisted the officer to manage the traffic situation.

The crew of the instrument flight rules (IFR) EMB110 did not receive traffic information on two IFR category aircraft that had departed Mitton Creek. The crews of the departing aircraft did not report taxiing prior to departure. The flight service (FS) frequency for the area was congested and it was difficult to communicate. Consequently, the crew was unable to coordinate the use of lateral or vertical separation techniques with the crews of the departing aircraft.

The aircraft was enroute from Alice Springs to Cairns and was displayed to the Daintree sector controller in the Brisbane air traffic control centre, as a green jurisdiction track and label. Without notice, the display changed to an uncoupled black track without label data, resulting in the sector controller losing situational awareness. Investigation revealed that the Cairns tower coordinator controller had cancelled the aircraft's flight data record (FDR) in the Australian advanced air traffic control system (TAAATS).

The coordinator had assumed that an aircraft on the ground at Cairns was the aircraft displayed as airborne and consequently felt it was unnecessary to check further prior to deleting the record. Local instructions precluded the cancellation of flight data records not under the coordinator's jurisdiction without prior consultation/coordination with other air traffic control units. The possibility of this occurring had been recognised by management and the instructions were issued in an endeavour to prevent inadvertent deletion of a flight data record.

TAAATS displays a warning message requesting confirmation of the requested action when a controller deletes an FDR for an aircraft. This message does not warn controllers that they do not have jurisdiction of the aircraft. Airservices Australia have proposed that the warning message for non-jurisdiction FDRs should be amended to alert controllers to the fact that coordination is required prior to deleting the FDR.

SAFETY ACTION

Local safety action

A request to change the warning message has been submitted by Airservices Australia Northern District (This is one of many TAAATS software modification requests that have been submitted). The modification is unlikely to be actioned in the short term due to the need to action higher priority tasks. Bureau of Air Safety Investigation safety action BASI will monitor Airservices' actions and, in particular, any system modifications which are made to prevent further similar occurrences.