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Concern summary

Safety concern regarding  the implementation of Temporary Restricted Airspace (TRA) at multiple locations, the use of short breaks and proposed enroute conditional endorsement (ECE) procedure. 

Reporter's deidentified concern

The reporter has raised a safety concern regarding the implementation of Temporary Restricted Airspace (TRA) at multiple locations, the use of short breaks and proposed ECE procedure.

Temporary Restricted Airspace

The reporter states that due to staff shortages, many air traffic controller shifts are unable to be filled resulting in several, normally controlled locations, being designated as TRA. The reporter states that those operating in TRA - line controllers, centre managers, pilots and operators do not have a proper understanding of the TRA procedures. 

From an ATC perspective, the reporter states that no-one has received training in implementing or managing TRA and the written procedures provided are inadequate to ensure a consistent application. The reporter states that some controllers manage the space by only authorising one aircraft in at a time. Put more simply, the principal of one aircraft out - one aircraft in. While other controllers permit multiple aircraft into the TRA at one time. 

From a pilot/operator perspective, the reporter states that it is evident that most crew do not have any understanding as to what TRA is, or how they are meant to operate within it. The reporter states that one airline does not permit aircraft into TRA due to the safety risks involved and the inability to implement risk controls at short notice, where as others seem oblivious to any changes in the airspace. The reporter gave an example of an international carrier flying out of Cairns in August 2022 during TRA airspace. The reporter states that it was evident that the crew had no idea what was happening. The tower cleared the aircraft for take-off and no further assistance was required to be given to the crew. Given the terrain around Cairns, other aircraft in the vicinity and the crew's unfamiliarity with the airspace rules, the reporter believes the scenario was unsafe.

The reporter's concern is that procedures for implementing TRA are inadequate to outline to controllers the process they should be following. The reporter states that controllers have received no training in TRA procedures, and reading through the procedures on their own, there is no clear guidance as to how access to the TRA should be granted or who is meant to grant the access. 

The reporter believes that the ad-hoc approach to TRA airspace is an accident waiting to happen.  

In addition to the TRA procedures, the reporter is further concerned by the use of the short break procedure in the Terminal Control Unit (TCU) environment and the proposed enroute conditional endorsement (ECE).

Short break procedure

The reporter states that the short break procedure allows the endorsed controller to leave the console for a break, and another controller, that doesn't have the endorsement for that sector, monitors the console while the original controller goes on the break. The reporter states that the short break procedure is primarily used in the enroute environment and was designed to be used with no, or minimal traffic and where no separation issues could exist. The reporter states that the short break procedure is now being utilised in the TCU environment, where aircraft taxi at short notice, or VFR aircraft call up unexpectedly.  

The reporter states that many controllers refuse to conduct a short break procedure as their ATC license is effectively being used to control aircraft when they are not present. The reporter is concerned that this procedure is being used more and more frequently in environments it was never intended for, and less experienced controllers are accepting the procedure thinking it is a normal process they are expected to comply with. 

Proposed enroute conditional endorsement (ECE)

The reporter further advises that controllers have been advised that an enroute conditional endorsement (ECE) is being proposed as a solution to the staffing shortages.  The reporter states that the ECE is a worse version of the short break procedure, in that a controller that doesn't hold an endorsement for the sector would be allowed to fully control any aircraft in the sector, and be required to perform nearly all the normal duties of an endorsed controller. However, the controller would have no training for the particular sector.

The concern is that the controller does not know the intricacies of the airspace and it is quite likely the controller could miss traffic conflicts that a controller that knows the airspace would never do. The reporter is also concerned that an ECE controller will not correctly identify the lowest safe issues and process aircraft in an unsafe manner, because it is a scenario that the controller would never have encountered before.  The reporter is concerned that the proposal of the ECE is a band-aid approach to a severe staffing shortage and brings additional risks.

The reporter queries the risk assessment to regularly utilise the short break procedure in the TCU environment and the proposed ECE procedure.

Further to the above, the ATSB has received a report from a flight training and charter operator also raising concerns regarding the implementation of Traffic Information Broadbase by Aircraft (TIBA) and TRA procedures at Rockhampton and Mackay. 

The reporter states: 

  • There is little to no notice of TIBA imposition, resulting in circumstances where solo students are operating in the area while TIBA procedures are implemented, and there were no indication of TIBA procedures coming into effect pre-departure.
  • Controllers (both in Mackay Tower and Brisbane Control Zone) unsure of TIBA procedures, and unable to provide assistance to aircraft who are querying procedures. On one occasion a pilot asked the controller what the implications of the TRA meant for them, and the controller replied 'I don't know'. 
  • Pilot's being unfamiliar with TIBA procedures and inconsistent application of TIBA procedures
  • Private pilots and non-commercial pilots operating in the area being forced out of the airspace or operating in the airspace with extreme difficulty
  • Brisbane Control Zone co-ordinating arrival times provide no flexibility on arrival and departure slots, resulting in aircraft not being permitted in the airspace due to unforeseen operational delays enroute, resulting in unscheduled diversions and low fuel events. 


Named party's response

Contingency Plans including Temporary Restricted Airspace (TRA)

Airservices has published contingency plans for many years. Version 1 of the current National Air Traffic Service (ATS) Contingency Plan was published in 2005 and detailed that TRA will not routinely be used to manage Air Traffic Services (ATS) Contingencies. The approach was based on the premise that airspace retained its ATS Classification, allowing Airservices to control access to airspace.

This premise was altered in 2008 when there was a change in regulation which resulted in determinations in respect of airspace of any class have no effect during any period in which ATS are not provided. As a result of this regulatory requirement, the National ATS Contingency Plan have been amended and it was determined at this time that the use of TRA would be used to encompass high density airspace for the purpose of access control to prevent overload of the contingency system.

The publication of the use of restricted areas in the contingency plans has been in place for over 15 years and the contingency plans are tested on an annual basis unless activated, which can then be used as the review. For 15 years, no issues have been raised in respect of the use of TRA. Airservices also includes contingency plan activation on the annual training plan from time to time.

In recent times, high levels of late notice staff unavailability has resulted in the activation of contingency plans on a more frequent basis than any previous period. Airservices acknowledges that there have been identified issues in relation to controller and pilot understanding of information published in Airservices internal documents and the Australian Aeronautical Information Publication (AIP). Work is being undertaken to try and simplify the issue with a meeting being held with Qantas, Virgin and the Civil Aviation Safety Authority (CASA) on 16 September 2022. A revised version is  due to be circulated for consultation.

It is important to clarify, that if no ATS is available then the airspace has no classification and TIBA procedures, an international standard, apply. As previously stated, Airservices then utilises a restricted area to restrict access. The risk to an aircraft in airspace with no ATS following TIBA procedures would be higher without the protection of a restricted area. In the Cairns example, the aircraft is entitled to depart into the airspace utilising TIBA procedures, regardless of whether the restricted area existed or not, this is a company decision. The restricted area limits traffic but does not change the procedures in use. There is also nothing that precludes an aircraft, in airspace where no ATS is available, flying published departure procedures. Unless being vectored, separation with terrain is always the responsibility of the pilot.

Short break procedure

The short break procedure is not domain specific; has been in place for many years; is subject to formal reviews; and, has been fully consulted with CASA. The reporter is correct in that the short break procedure can only be used when air traffic activity is minimal and does not require air traffic controller action for the separation of aircraft. The short break procedure has additional controls and limits the interaction by a controller who is monitoring the frequency to that detailed by the executive controller. Responses are extremely limited and do cover scenarios indicated. Airservices considers the use of the procedure to be safe.

Proposed enroute conditional endorsement (ECE)

Airservices is following its safety management system and change processes as it works towards a conditional endorsement. Airservices already has location specific conditional endorsements in place. This proposed enroute conditional endorsement is on a broader scale and as such controls are being developed that fit the airspace that the controller is expected to manage. These include checklists, system maps and traffic management.

The proposed endorsement will follow the protocols detailed in the Civil Aviation Safety Regulations part 65 which allows for both location specific and functional endorsements. Airservices has consulted with staff and taken input into the process. CASA has also been briefed on the proposal which will increase the number of available staff and is aimed to prevent airspace being left with no ATS available and being subject to TIBA procedures.

Additional report

In relation to Rockhampton and Mackay, Airservices disputes the statement in relation to notification of the procedures. The NOTAMs indicating the period of no ATS available are published in sufficient time that any pilot would have had access to them when undertaking pre-flight briefing prior to commencing a training flight. As stated previously, Airservices does acknowledge that there is some misunderstanding within ATC regarding the contingency procedures and is working to improve the understanding of its staff. However, the TIBA procedures are published in the Australian AIP and it is not Airservices responsibility to train pilots in relation to procedures contained in the AIP. The NOTAMs contain the information in relation to the restricted area, which is used to control access.

The additional report makes reference to low fuel events. The AIP requires aircraft to report minimum fuel or MAYDAY fuel and also deals with the reporting of such occurrences. Where a pilot reports minimum fuel or MAYDAY fuel, Airservices staff will report such occurrences through CIRRIS and Responsible persons (Pilots) are required to routinely report such matters to the ATSB. Airservices has reviewed its data, and no such occurrences are recorded so we are unable to make any comment on this aspect of the report.

In regard to unscheduled diversions, Airservices is unable to provide comment on this aspect of the report as we are unaware of such diversions by training flights and is in regular contact with Airline operators where we are aware of one such issue due times published on the NOTAM.

Finally, restricted areas are used to limit congestion and reduce the risk of airborne conflict. Slots are provided and normally have a 15-minute window and it is acknowledged that there is limited flexibility if the window cannot be met. Many of the periods of no approach ATS at Rockhampton and Mackay are 30 minutes periods to facilitate a break for a single duty controller. It is acknowledged that there have been periods of longer outages where no staff have been available that may give rise to the statement.

Regulator's response

In relation to the use Temporary Restricted Areas (TRA) with Traffic Information Broadcast by Aircraft (TIBA) procedures as a contingency measure.

As a concept, TRA with TIBA has been in place for over 14 years. In 2008 it was decided that TIBA should not be enacted without a TRA.

However, the rate of application had been limited to approximately 5 TIBA events per year with most in enroute airspace, 2022 has seen significantly many more TIBA occurrences with many in approach/departure airspace.

CASA views the current use of contingency management practices as unsustainable and is actively engaging directly with Airservices Australia (AA) to assist them to address the underlying drivers so that they can deliver services to the expected level. Whilst the contingency practices used do provide an acceptable level of safety performance at the location level, the widespread regular use of contingency practices across the entire system may introduce additional risk which will need to be monitored.  CASA intend to address the root cause of the issues raised, through a combination of surveillance (key focus areas), enforcement and direct consultation.

In relation to the use of the short break procedure in a TCU.

Historically the short break procedure has been principally utilised in the enroute environment; however, there is no restriction as to which ATC stream it applies.  The short break procedures are only to be taken when air traffic activity is minimal and not requiring air traffic controller action for the separation of aircraft.  As the relieving controller is required to reply with phrases, such as 'STAND BY' or 'WILL ADVISE' only, safety is likely to be maintained albeit at the expense of efficiency.  Use of the procedure in the terminal environment does not appear to be in breach of any standards or practices.

In relation to the proposed enroute conditional endorsement (ECE).

CASA is aware that Airservices are considering the development of an ECE; however, no detailed information has yet been provided to CASA.

It is probable AA are seeking to increase the use of what is known as a Restricted Endorsement. Holding a Restricted Endorsement enables an air traffic controller to control additional airspace in which traffic levels or complexity are considered very light. There are limitations on when a Restricted Endorsement can be exercised, which means that its use is often limited to overnight operations only.

In relation to the specific use of TRA with TIBA at Rockhampton and Mackay.

Since the commencement of Increased Surveillance Services (ISS) on 16 June 2022, Coral Approach has experienced contingency procedures most weeks due to staff availability.

CASA issued a Safety Finding to AA on 11 November for failing to ensure there were sufficient qualified staff to provide the air traffic services for Coral Approach.

CASA is working with AA to consider the most appropriate contingency arrangements to make whilst AA address the Safety Finding.