Remote digital tower installations around the world have already shown the decreased cost and increased safety benefits compared to bricks and mortar towers. The digitalisation and virtualisation of air traffic control (ATC) systems empower air traffic controllers (ATCO) to work from any location, but also to serve any airspace – even beyond national or regional borders. In regions where smaller, low traffic volume airfields are at risk of closure, the remote tower concept allows ATC operations to be located at an easily accessible site, reducing staffing issues.
On top of that, the idea that several low traffic airports can be served and consolidated into one remote tower centre offers additional cost benefits. This solution provides enormous potential in terms of process optimisation, utilisation of resources and functional synergies across multiple airport locations. But how does this work?
The concept of one Air Traffic Controller managing more than one airport has been tested in both simulation and real-life situations as part of the SESAR 2020 research program, since 2017. There are many locations around the world with small, remote airports that require surveillance but have a very small number of aircraft movements. The challenge is often two-fold; the tower could be in a remote location, away from civilisation, making recruitment difficult; the second is that the controller spends a large proportion of their day with nothing to do. This is not only counter-productive but also not the best situation for a job that requires extreme focus and preparedness. A remote digital tower solves both those problems with the relocation of the tower operations to a bespoke facility, in an accessible location, and to avoid accidents through a smartly balanced ATCO workload.
Adding multiple airports to the same remote tower position was first put to the test at the German Aerospace Centre (DLR) Air Traffic Validation Center in Braunschweig, Germany. In a human-in-the-loop, real-time simulation, seven Hungarian civil and military controllers managed up to 30 movements per hour at three Hungarian airports. DLR researchers and Frequentis human factors experts assessed the controllers’ line of sight, their perceived situational awareness, workload, and acceptance, as well as efficiency and safety while handling the various traffic situations. Altogether five simulator validations and one live validation with a real-time working position in Budapest for three local Hungarian airports were conducted. This allowed the overall operational feasibility of the concept to be reviewed, and the design of the controller working position to be agreed upon. DFS and Frequentis developed a prototype, which is characterised by a high level of system integration. We expect the first multi remote tower centre to be established before 2025.
Combining tower and approach
Although a remote digital tower provides location-independence for ATC services, the same doesn’t apply to approach services, yet. However, if remote tower facilities are already in place, it is then possible to integrate that with approach control so that traffic flow in the upper airspace can be monitored and aircraft landing and departure slots can be scheduled more efficiently. With this hybrid tower and approach solution, there is also the potential for the same ATCO to manage both tower and approach in times of low traffic, with the option to combine or split the service based on traffic load. This is something that was missing during the pandemic when air traffic was at a standstill because, without the ability to combine both services, the tower still needed to be fully staffed. A costly exercise when revenue streams had come to a halt. Naviair, the Danish air navigation service provider, selected the integrated tower and approach solution from Frequentis DFS Aerosense in early 2020 to manage increasing airspace demand and support the workload of ATCOs. This will be the first time that both digital tower and approach services have been combined as one integrated system.
Important to note is that with a remote tower visual representation of an airfield, consistent and reliable network performance is mandatory. This means no interruption in voice/data transfer or image quality, essential for remote and isolated airports. What is required is an ATM-grade network capable of detecting any degradation in network performance, known as brownouts, compared to a conventional network that only reacts to total link loss, blackouts. A network that allows dynamic rerouting based on application priorities and bandwidth availability, will eliminate loss of service or reduced image quality.
Turnkey services from concept to go-live
Cutting-edge technology is also only one part of what is needed for a successful project; equally as important is an operational concept, which is based on clear and concise customer needs and a sound business case. Implementing remote ATC operations includes the need to adapt air traffic service (ATS) procedures and consulting, ATS training and transition, support during the regulatory approval process as well as stakeholder management throughout the whole implementation process.
For further information on digital tower solutions, meet us at the Kaivopuisto Air Show in Finland, 6-7 August 2021.