During planned stop-work meeting by air traffic controllers,
Airservices Australia (Airservices) enacted a contingency plan for
the Melbourne Flight Information Region (FIR). That plan amended
Class A and C controlled airspace (CTA) to temporary restricted
airspace (TRA) and limited the number of aircraft able to fly in
the TRA. The plan required pilots of aircraft not approved to fly
in the TRA to leave controlled airspace by 1015 CSuT. A Cessna
Aircraft Company Citation (Citation) was seen on radar to be
operating in the TRA after that time and in potential conflict with
a Boeing Company 737 (737). The Adelaide Approach East controller
issued traffic information and clearances to enter controlled
airspace to the pilots of both aircraft that ensured their
separation.
There were no separation standards applicable to aircraft in the
TRA. Recorded radar data indicated that the vertical and lateral
spacing between the aircraft exceeded the vertical separation
standard of 1,000 ft (for aircraft below flight level (FL) 290) and
the radar separation standard of 5 NM that would normally apply to
aircraft in CTA.
Civil Air, the Australian Air Traffic Control Association
notified Airservices of the proposed stop work meeting on 8 March
2002. On 12 March 2002, Airservices issued a notice to airmen
(NOTAM) C22/02 regarding the controllers' standdown period between
1030 to 1430 on 13 March 2003. That NOTAM advised that a temporary
restricted area and limited route structure would be activated and
that specific details would be notified by a subsequent NOTAM.
Later that afternoon, Melbourne FIR NOTAM C708/02 was issued
advising that pilots of aircraft not in receipt of an approval to
operate in the TRA were to be clear of CTA by 1015.
During the morning of 13 March 2002, sometime between 0830 and
0900, the Citation pilot telephoned Airservices requesting approval
to fly in the TRA. That request was denied and the pilot
subsequently planned to leave CTA, by descending en route, at 1015
in accordance with the NOTAM. The 737 pilot was approved to fly in
the TRA.
Prior to the activation of the TRA, the two aircraft were under
the control of the Melbourne Centre Canty sector controller. At
about 0930, that controller received a temporary local instruction
and other documents that detailed how the Canty airspace would be
transitioned from CTA to TRA. An FIR Manager was available to
assist controllers in the Barossa Group, of which Canty was one
sector. At 1020, the Citation pilot requested a clearance to
descend to FL200, a level outside the TRA. The Canty sector
controller approved the descent but then advised the pilot that he
could remain in the TRA. The pilot acknowledged that radio
transmission and advised the controller that he would remain in the
TRA. The controller was not aware of what aircraft were approved to
operate in the TRA.
The plan called for controllers to record details of aircraft
that remained in the TRA for subsequent checking by a manager. The
intention was to confirm that only aircraft approved to fly in the
TRA were actually in the area. At 1025, the controller broadcast
that control services were terminated and those pilots should
operate in accordance with the TRA NOTAM and closed the Canty
sector control position. The controller recorded that both the
Citation and the 737 were in the TRA. As Melbourne Centre staff
were checking the approval status of the aircraft remaining in the
TRA, they were notified by Adelaide Approach controllers that the
Citation was in the area without approval.
The contingency plan was developed in 1997 to provide a
structured response to, and recovery from, a failure of air traffic
services. The plan was reviewed in 1998 - 1999 in preparation for
the information technology problems expected during the 2000 new
year, and updated in 2001. The plan was broad based and there was
limited detail on how it may actually be implemented. When
Airservices was notified of the controllers' standdown, it was
perceived that a limited segregation service, using the plan, could
be offered to assist the aviation industry. The plan was modified
in conjunction with the two primary airline operators and the
resultant contingency plan complemented their individual company
plans.
More detailed local plans, to address the transition to/from the
contingency plan, were developed during the period before the
notified standdown. Those local plans were not developed in
accordance with Airservices safety management processes.
A review of the plan and associated procedures was conducted
following the standdown and considerable changes were made before a
second similar standdown, involving Sydney and Brisbane
controllers, a week later. A further review was conducted after the
second standdown and, as a result of both reviews, 139 items were
identified for action. A safety assessment of the contingency plan
was subsequently conducted in April 2002 resulting in further
changes to the plan. Those changes also included limiting the
future declaration of a TRA to Class A and C airspace over
Australian territory.