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Reach for the Onesky, Australia’s integrated air traffic management system

written by Ian Thompson | February 23, 2019

This story about the Onesky air traffic management project first appeared in the December 2018 edition of Australian Aviation.

An aerial look at Melbourne Airport. (Lachie Hare)
An aerial look at Melbourne Airport. (Lachie Hare)

The $1.2 billion joint civil-military air traffic control system now under development provides the foundation for a new generation of Australian air traffic management.

Government aviation policy papers in 2009 proposed that considerable organisational and operational benefits would come from collaboration between Airservices Australia and Defence.

Both organisations have air traffic management (ATM) systems due for replacement at around the same time. This provides a generational opportunity for both organisations to align their ATM systems, as well as achieve benefits from other areas of harmonisation.

Airservices currently relies on The Australian Advanced Air Traffic System (TAAATS) of hardware and software for its traffic control. Defence, meanwhile, uses ADATS, the Australian Defence Airtraffic System.

Thales Australia has been awarded the prime contract to deliver the new Civil Military Air Traffic Management System (CMATS) – a single, national, integrated air traffic management system. OneSKY is the name of the overall program that aims to harness the capability and benefits CMATS can provide.

For example, Airservices aims to maximise the benefits available under OneSKY to make significant overall business changes.


The existing TAAATS system comprises two air traffic control centres – Brisbane and Melbourne – each responsible for about half the airspace across continental Australia. Both traffic control centres will have independent flight data processing systems, providing terminal control radar and tower services at all major cities within their area of responsibility.

Defence currently operates a network of control towers and approach radar locations, although radar approach services for Richmond, Pearce and Edinburgh are provided from Airservices facilities. ADATS currently incorporates radar sensors (fixed and deployable), software and display systems, communications systems and radar simulators for the school of air traffic control and military approach units.

By way of context, CMATS could be considered part of the third-generation of ATM system development. The first generation involved the introduction of radar systems and ground based navigation aids. Digitisation of air traffic control data through radar and flight data processing systems could be considered the second generation. The third generation involves ATM systems that have been developed to cater for large increases in traffic, while reducing the operational costs to airspace users. Some of the initiatives include satellite-based navigation, surveillance and communications, information management systems that dynamically link aviation stakeholders, and ATM system functionality that enables aircraft to operate on their most optimum flight profile.

The new ATM systems, CMATS included, have their origin in the United States’ Next Generation Air Transportation System (NextGen), and Europe’s Single European Sky ATM Research (SESAR) program. Both programs shared common goals: to provide for a threefold increase in capacity; to improve safety by a factor of 10; to deliver a 10 per cent reduction in the environmental impact per flight; and reduce ATM costs to users by 50 per cent. Generational change was required to ATM systems and procedures to achieve these goals.

CMATS integrates Australia’s civil and military ATM functions with both running off the same flight data processing system. A single flight information region (FIR) will replace the existing two FIRs plus the Defence ATM system. This single FIR, comprising domestic and oceanic airspace, will encompass 11 per cent of the Earth’s surface.

Although air traffic control centres will still be located at Brisbane and Melbourne, system integration allows for dynamic switching of air traffic control functions between the two locations. Any civil or military en-route sector, terminal or control tower position can be quickly configured to manage air traffic in any portion of Australian airspace. This flexibility enables CMATS to overcome disaster events, staff shortages or equipment issues, and assign resources to deliver route flexibility under changes to wind conditions.

Although air traffic control centres will still be located at Brisbane and Melbourne, system integration will allow for dynamic switching of air traffic control functions between the two locations. (Airservices)
Although air traffic control centres will still be located at Brisbane and Melbourne, system integration will allow for dynamic switching of air traffic control functions between the two locations. (Airservices)

This level of control function integration under one flight data processing system has not been undertaken by other major air navigation service providers (ANSPs). NATS, the United Kingdom ANSP, for example, operates three flight data processing systems within its domestic airspace: London terminal control and area control, plus Scotland area control.

The United States also operates 20 en-route control centres that use separate flight data processing systems.

According to Chris Deeble, Airservices OneSKY Program executive, “CMATS offers greater operational flexibility and the opportunity to generate significant cost savings for airspace users. Taking account of the existing and forecast traffic levels, all undertaken within a single FIR, CMATS is around five to eight times more complex than any other air traffic management (ATM) system that is operating anywhere in the world.”

A cost-benefit analysis conducted by Deloitte has identified around $1 billion economic benefit over the operational life of CMATS through cost reductions allied to greater operational efficiency.

First, CMATS will deliver capacity for airspace users to operate on user preferred routes (UPRs) across Australian transcontinental airspace. UPRs enable aircraft to take advantage of high level wind flows thereby reducing flight times and fuel burn. These UPRs extend into the oceanic airspace of adjoining ANSPs and beyond.
Second, trajectory-based operations enable aircraft to plan their arrival using a continuous descent from cruise to touchdown.

Third, greater predictability and access to special use airspace, particularly military restricted areas, reduces route length and enables aircraft to operate at their optimum flight level.

Airservices deputy chairman (and former Chief of Defence Force) Mark Binskin with Defence Minister Christopher Pyne at the recent opening of Thales Australia’s new Melbourne offices for its OneSKY project team. (Defence)
Airservices deputy chairman (and former Chief of Defence Force) Mark Binskin with Defence Minister Christopher Pyne at the recent opening of Thales Australia’s new Melbourne offices for its OneSKY project team. (Defence)

Aircraft flying preferred routes and at most efficient flight levels sharply increase the complexity of air traffic controller workloads.

Software tools are required to help controllers identify conflicts between flights and provide alerts when aircraft are not following clearances. Some examples of tools within CMATS include: arrival management systems to plan an orderly flow of aircraft landing at airports; a satellite-based data link to provide pre-departure clearances; and formation flight and clearance management for military aircraft, providing conflict detection.

The flexibility in configuring and allocating air traffic controller sectors is expected to deliver cost reductions through greater workforce efficiency. It will enable assignment of air traffic controllers to sectors with the greatest numbers of aircraft. To achieve this, a shared system-wide view is available from all CMATS workstations allowing for tactical arrangement of airspace sector configuration. Air traffic controllers will share a common understanding of flight parameters when aircraft are crossing between adjacent sectors.

Although the contract with Thales was officially signed in February 2018, early CMATS works began in early 2015 involving exhaustive deliberation of Defence and Airservices’ CMATS system requirements.

“We wanted to address major items on the critical path as early as possible, prior to getting into the contract,” Deeble said. “The system requirements’ review was also undertaken to de-risk the program from both the customer and supplier perspective. This gave us a good idea about the congruity between our requirements and Thales’s interpretation of them. Many plans were also agreed prior to contract signature.”

The advanced works undertaken by Thales also provided for the early implementation of the voice communication system. At the end of 2018 and early 2019, four sites will have the new voice system operational ­– an important element in being able to dynamically assign air traffic control staff to manage different portions of airspace.

“From a technical perspective, CMATS is probably a different level of complexity compared to some bespoke Defence programs, like Project Wedgetail. But the CMATS system is of critical importance to the Australian nation, travelling public and the aviation industry,” Deeble said.

“It is a very significant and complex undertaking. I wouldn’t consider CMATS at the bleeding edge of technology, but it remains complex architecturally and its dependency on networks to transfer data between many civil and Defence sites will present some challenges. A project of this scale, integrating civil and military elements within a single FIR, has not been attempted by an ANSP elsewhere.”

The introduction of CMATS involves strong inter-organisational relationships between Airservices, Defence and Thales. Deeble explained: “The inter-organisational relationships present a considerable challenge. Defence and Airservices often bring different cultural perspectives in what they do and how they go about doing it. For Defence, air traffic control is an enabling and supporting function to get warfighting capability into the air to perform various missions. With Airservices, air traffic control is its core function.

“The two organisations have different funding arrangements. Airservices obtains funding from its long-term pricing agreement with airspace users. Defence, on the other hand, has appropriations coming from government to fund its activities. It is used to undertaking many large projects while Airservices undertakes these large projects much less frequently, generally at 15-year intervals. A lot of work needs to take place with the people from the two organisations to manage these differences to keep the CMATS progressing on an even keel.”

The joint program team is an important mechanism to integrate the interests of both organisations. The project team comprises around 65 people from Airservices. Defence, meanwhile, has 16 staff embedded within the Airservices project team as well as providing others, when needed, who are undertaking work on other air traffic control-related projects. In effect both organisations provide about the same number of people for project activities.

An agreement has been crafted between Airservices and Defence, mirrored in the Thales contract. It outlines the principles applied in working together based around teamwork and best-of-program thinking. A governance framework includes escalation processes to resolve differences that can’t be worked out within the project team. The aim is to escalate issues and gain resolution quickly.

The contract with Thales also includes a target cost incentive model intended to promote a collaborative working relationship with the company. The goal is to incentivise Thales to be more efficient in performing project tasks and identify opportunities to work collaboratively with Airservices and Defence to reduce project time and costs. Gains will be shared between the three organisations if program work is performed more efficiently than planned and delivers costs lower than forecast.

“From my experience it is essential to work the various relationships involved in the project,” Deeble said. “If you can understand the relationships you can then get the best outcomes for the parties. Working together to resolve problems is essential rather than letting them fester.”

Deeble said that while the relationship between the entities should be considered a work in progress, the project plan as agreed with Thales was “on track”.

“My aim is to identify and tackle issues early, not wait until a contractual dispute erupts,” he said.
“Although there is still seven years work ahead of us, I think we are in a good place.”

Baseline code for CMATS is already running at Thales’s Melbourne development centre. The first human-machine interface software elements have been delivered on schedule. ATM software, termed TopSky New Generation, is being developed simultaneously by Thales at their sites in Paris, Toulouse and Melbourne. Thales United Kingdom is developing software that will be used in the fallback ATM system. It will be used if the main software ceases to operate for some reason.

A single FIR provides a complete picture of air traffic across Australia. Since any workstation can control any piece of airspace, the system provides for strong business resilience in the event of a disaster or catastrophic event. The main flight data processing system and data repository is located in Melbourne. Should the main processing centre in Melbourne fail, for whatever reason, the redundant system in Brisbane will assume responsibility for undertaking flight data processing. Although only a backup system, processing of flight information and data storage would be ongoing in Brisbane. In the event of a Brisbane failure, controller work stations can stand alone and operate locally.

One of the most significant changes CMATS will bring is a new approach to information management for all users of the ATM system. A system-wide information management system (SWIM) is being developed to exchange information between various stakeholders and users.

SWIM presents the opportunity to use cloud-based technologies, another new challenge for Airservices and Defence which, up to now, have controlled safety-critical infrastructure and systems directly through in-house engineers and technicians.

Cloud solutions mean that these functions will likely be undertaken by other organisations. “At the moment we are exploring the use of cloud-based technology. Our current thinking is that we will limit the cloud applications to those items that are not mission, safety or time-critical,” Deeble said.

“Other items, such as capturing technical data and its storage, will probably be performed in a cloud environment.”

CMATS will also deliver a greater flow of information between the ATM system and airlines and airports. At the moment, CMATS is primarily focused on how aircraft are controlled. The information that is generated from CMATS data will be accessed by airlines and airports through applications that sit outside CMATS, such as the flow management system. While an information exchange may occur in the future, the priority at the moment is for CMATS to only feed these applications with flight data.

These applications are developed by other software suppliers. In the past, the prime supplier of the ATM system was responsible for developing or integrating other applications. Airservices is now reflecting on what functions it does or does not keep within its organisational umbrella.

Testing the new CMATS voice control system. (Airservices)
Testing the new CMATS voice control system. (Airservices)

Previously it had been thought that all applications would be built into CMATS. It is now considered that ‘best of breed’ applications such as long-range flow management, workflow management, data analysis and reporting, are better developed by others and managed outside CMATS.

Cyber and broader security features are being built into the system as part of the system specification. The flow of information between civil and military functions presents difficulty in managing the acquisition and subsequent use of information that may have security implications. To provide protections, Thales is required to develop CMATS to comply with the government security policy framework. The Australian Cyber Security Centre will also help with its certification.

“At the moment, most of Airservices’ air traffic management information is not security-classified. Existing procedures and practices exist for how this data is gathered and stored”, Deeble said. “Our intent is that elements of the CMATS will be classified at the protected level and cyber security will be built into the system from day one, rather than trying to add these important elements as afterthoughts and introduced later.”

The use of third party applications presents further security management concerns. Applications that involve extensive interaction with multiple stakeholders, such as with airlines and airports, can only involve lower levels of security. The exchange of data only between Airservices and Defence through CMATS can provide much greater protections. Protection for information managed by cloud-based technologies is currently being explored.

From an organisational transition perspective, CMATS presents an upside to Airservices compared with the introduction of TAAATS which involved considerable staff training to change from paper-based to electronic recording of flight data. There remains a challenge for Defence, however.

“For Airservices the transition from TAAATS to CMATS will not be as significant as the transition required for Defence from ADATS,” Deeble said. “ADATS still involves paper strips and did not undergo a great deal of evolution over its life. Under CMATS all military locations will undertake electronic recording of aircraft.”

The capacity of CMATS to deliver the tactical allocation of air traffic controllers to manage different portions of airspace provides the opportunity to significantly improve staffing efficiency. Within Airservices, the Customer Service Enhancement (CSE) division is exploring the changes that need to take place within the organisation to deliver the promised CMATS cost savings. For example, performance-based endorsements are being introduced for air traffic controllers to enable staff to work an increased number of sectors which all share many common characteristics.

The first release of CMATS, involving Amberley and East Sale, as well as some software support functions will become operational at the end of 2022. Most Airservices locations and other Defence sites will become operational around mid-2024. The final version of CMATS software will be dropped into all sites by early 2025.

VIDEO: A look at Onesky from the Airservices Australia YouTube channel.

This story first appeared in the December 2018 edition of Australian Aviation. To reach more stories like this, subscribe here.


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