The reporter has raised a safety concern in relation to the Ground Delay Program (GDP), a traffic management initiative to assist with air traffic flow management, not being activated resulting in excessive controller workload.
The reporter states, prior to a recent procedure change, the National Operations Management Centre (NOMC) would initiate and coordinate the GDP. The procedure was amended so that the Air Traffic Manager (ATM) would liaise directly with Airservices Australia (AsA) senior management to coordinate the GDP.
The reporter states, on [date] the GDP should have been activated with poor weather at [Location 1], [Location 2] and [Location 3]. A decision was made by AsA senior management not to activate the GDP concerned about the 'optics'. This decision resulted in [Location 2]-based controllers remaining plugged into their consoles from 3 to 4 hours. The reporter further states, the controllers' enterprise agreement stipulates controllers should be confined to their consoles ideally for 2 hours, not to exceed 3 hours for fatigue mitigation.
The reporter finally states, with the increased level of airborne traffic, controllers reported losing situational awareness for certain periods during this time.
Accountabilities and responsibilities:
The Air Traffic Management Director (ATMD) (as per National ATS Administration Manual (NAAM) 1.7.3.2) have overall responsibility for service provision within the Brisbane and Melbourne Flight Information Regions (FIR) and will preside over decisions which impact the National Airways System (NAS) beyond the area supervised by individual shift manager (SM). They also must plan and oversee the management of operations, traffic density and complexity within the FIRs ensuring maximum safety, effectiveness and efficiency of operations.
The Shift Managers (as per NAAM 1.7.3.3) have responsibility for service provision within their area as defined in local instructions. However, any decision which may impact on the NAS outside this area must be referred to the ATMD unless this decision is explicitly documented as their responsibility. Additionally the SM’s must:
a) regulate staff workload through the timely implementation of traffic management strategies
b) manage airspace and/or aerodrome configurations to provide safe and efficient access to airspace users
c) manage systems to provide accurate information which informs controller situational awareness
d) manage the de-concentration and consolidation of operational positions to meet the traffic demand.
When issues were raised with the ATMD on the day, the ATMD worked with the Shift Managers to respond to late notice network impacts due to un-forecast weather events in [Location 2] and a combination of weather and emergency events in [Location 1] in the late afternoon/evening.
Pre-tactical plan for the [date] - ATMD accountability:
The NOMC uses a Collaborative Decision Making (CDM) process to pre-tactically assess the predicted hourly weather in the Air Traffic Flow Management (ATFM) ports for using a combination of Terminal Area Forecasts (TAF)’s and weather modelling systems to gain a consensus of weather conditions. These conditions are then converted to runway arrival rates through the use of tried and tested business rules that have been developed with Industry, Airservices and Bureau of Meteorology. This is known as the Meteorology and Collaborative Decision Making (METCDM) process and involves AVMET units from [Airline 1] & [Airline 2], NOMC MET from the Bureau of Meteorology, NOMC CDM/ATFM team, ATMD and Air Traffic Control (ATC) Shift Managers.
The ATMD then makes a final decision on the activation of a GDP based on defined rules or network need.
The pre-tactical assessment of the weather for the [date] showed airborne delays remaining below En-route Supplement Australia (ERSA) published values and did not meet the triggers for the activation of a [Location 1] or [Location 2] GDP. (Weather models for [Location 1] and [Location 2] provided to the ATSB and CASA).
Day of Ops:
The weather impacting [Location 2] through the morning and late afternoon/evening had not been forecast to impact arrivals rates to the level experienced on the day. As per NAAM, the Shift Manager must regulate workload and manage the units resources to meet the demand requirements or put in place mitigation to suit.
On the day while some Shift Managers were excellent in coordinating with the ATMD and being proactive in managing the workload of the group, there were other Shift Managers who were very late reacting to delays already in the system before approaching the ATMD to discuss. The ATMD assessed traffic, delays, staffing, weather and potential Traffic Metering Initiatives (TMI)’s with the SMs to enact the best solution.
A Level 2 GDP was enacted for [Location 2] in the evening when it was reported to the ATMD that there were nil approaches being made. This was enacted to return delays to below ERSA which was successful.
Temporary Local Instruction (TLI)’s and Governance:
Two TLI’s have recently been issued in relation to network management:
- TLI_24_0339 Chief Airspace Network Officer (CANO) approval for network management tools (effective 2412020200 UTC)
- This TLI is to provide a level of oversight for pre-tactical planning to ensure there is a fair balance between both network capacity and airline operational needs. ATMD, Head Network Planning & Optimisation and the NOMC meet with the CANO to discuss pre-tactical plans taking into account recommendations from the NOMC, ATMD, staffing availability and METCDM process.
- TLI_24_0342 Use of tactical traffic management initiatives (effective 2412032230 UTC)
- This TLI provides a background of network management requirements for all parties, and:
- Clarifies the requirements stated in C-PROC0381 Network Operations Procedure Manual to ensure that actions that have a fundamental impact on the network and efficiency of the network must have ATMD approval.
These TLI’s were not in effect on the [date].
Safety Events recorded:
[Report number]: Other – non-safety related: Traffic metering [Location 3] approach departures due en-route requirements enacted
ATC Enterprise Agreement
20.17 Breaks from continuous duty
(a) ATCs should not work more than two (2) hours without a break but must not exceed three (3) hours without a break, except in extraordinary circumstances which could not have been reasonably foreseen by Airservices.
(b) Where such extraordinary circumstances occur, the denial of the break can only be for a limited period of time whilst these circumstances are addressed by Airservices. This will include the situation where Airservices is unable to replace a shift because less than eight (8) hours' notice has been provided to Airservices of a staff member’s absence. In these circumstances, breaks of limited duration may be accommodated through the use of contingency arrangements.
The events of the day with weather impacts beyond that was forecast could not have been reasonably foreseen by Airservices.
Improvements:
Following feedback from SMs and ATMD on the day it was found that there is a potential gap in some knowledge and skills in relation to:
- proficiency with Harmony or Maestro to the level where they were ahead of the network
- all accountabilities and responsibilities of the Shift Manager role.
The Network Operations Manager and Head Aerodrome and Airspace Services [Location 2] are working together to improve this.
CASA has reviewed the report and Airservices Australia’s response, including the changes implemented in late December 2024.
We are continuing to work with Airservices to support the implementation of their approved Fatigue Risk Management System (FRMS), as required under Part 172 MOS.
CASA does not propose further action at this time.