Compromised separation recovery training
Date issue released
Safety Issue Description

Airservices Australia had not provided en route air traffic controllers with effective simulator-based refresher training in identifying and responding to compromised separation scenarios, at intervals appropriate to ensure that controllers maintained effective practical skills.

Issue number
Transport Function
Aviation: Airspace management
Issue Owner
Airservices Australia
Mode of Transport
Issue Status Justification

The ATSB is satisfied that this safety action satisfactorily addresses the safety issue.

Proactive action
Action number
Airservices Australia
Action date
Action Status
Action description

On 1 September 2014, Airservices Australia (Airservices) advised the ATSB of safety action relating to compromised separation recovery training.

Airservices established the SkySafe Taskforce which conducted a review into compromised separation recovery training, with respect to both content and management of the training.  The review identified 14 recommendations for continuous improvement in these areas, to ensure a quality training program for air traffic controllers. All actions were completed by mid-March 2014. 

A recommendation to undertake consultation with industry on Australian Aeronautical Information Publication (AIP) phraseology to ensure a common understanding of the urgency and application of procedures in compromised separation occurrences was addressed through the provision of a Safety Bulletin provided to the broader aviation community on 7 March 2014.

A recommendation to examine and update for consistency the safety alerting sections of the Manual of Air Traffic Service (MATS) and the AIP was completed through revision of AIP and MATS and the subsequent release of amendments on 21 August 2014 to ensure alignment. 

In response to nine recommendations relating to the provision, documentation and management of compromised separation recovery training requirements, amendments were made to Airservices’ Air Traffic Services (ATS) Training Operations Manual.

Compromised separation recovery training learning resources were developed in accordance with two recommendations relating to updating all compromised separation training to include details on traffic collision and alerting system functionality and pilot perspectives, Short Term Collison Alert parameters, differing control intervention requirements depending on differing escalation factors, guidance on actions to be taken where the subject aircraft are not under surveillance, and the means of making controllers aware of the updated compromised separation recovery training content.  The learning resources support the delivery of online, classroom and simulator training.  .

The 14th recommendation to ‘Identify and include in the Safety Investigation Procedure the method and forum where systemic and significant safety issues are escalated’ was completed through the creation of an internal Letter of Agreement between Airservices’ Safety Services and ATC sections.

On 25 July 2014, following development work and consultation with Airservices’ ATS Operational Training section, a Standardisation Directive communication was issued to controllers to clarify the structure and phraseology of the air traffic control response (ATC) in relation to compromised separation recovery situations. 

On 8 August 2014, a summary of the ATC Compromised Separation Recovery Training and ATC structure response was presented at Airservices’ 31st ATS/Airline Safety Forum as part of broader industry consultation and collaboration.

On 30 March 2016, Airservices advised of additional outcomes from the SkySafe Taskforce, which included:

  • review of the quality assurance and governance around the content of training material
  • codification of the competency elements of an effective compromised separation recovery response to reconcile the need for a response to contain certain elements whilst still providing the flexibility to tailor responses to each scenarios. This has led to the creation of the technique known as 'TRUCT' (Trigger, Resolve, Urgency, Confirm, Traffic).
  • implementation of a 6-month assessment regime that includes a requirements for ATC to demonstrate the use of compromised separation phraseology in a challenge-response situation with the check supervisor
  •  implementation of increased warning time of Short Term Conflict Alert (STCA) in the en route airspace from 60 seconds to 90 seconds which provides additional window of opportunity to identify and respond to compromised separation scenarios.

Airservices also reported that the organisation was taking action to provide a part-task simulator solution in support of the 6-month assessment regime on compromised separation skills.

This solution will be suitable for en-route and terminal area (TMA) and will also be examined for feasibility to be introduced into the tower environment. The part-task simulator is under trail at this time and depending on the outcomes, may form part of the annual compromised separation training requirement.