In the future, today's airport towers could be replaced by control centres to which several airports are connected for remote control. At the end of 2021, within the context of SESAR, the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR) and Frequentis set up a remote tower centre prototype from which Lithuanian and Polish air traffic controllers provided aerodrome traffic services to a total of 15 simulated airports. The trial showed that the idea of large-scale remote tower centres works.

"In the test campaign, we prototyped newly developed planning tools for these large remote tower centres," reports Jörn Jakobi from the DLR Institute of Flight Guidance. "These planning tools will be of central importance in these new working environments to optimally organise and utilise the available resources."

A promising concept for small, but also for medium and large airports

Rather than relying on a few air traffic controllers in a single tower, there is a whole pool of air traffic controllers working in a remote tower centre, which means they can be deployed more flexibly when needed. Smaller airports in particular, where demand is high on weekends and public holidays but low during the week, can be operated more efficiently this way. "If the traffic volume at several airports drops significantly, a single air traffic controller can control some of them simultaneously," says Jakobi. Medium-sized or large airports could also benefit from remote control by a centre. If the traffic volume increases during peak hours, air traffic controllers from the pool can provide support for a short time. A continuous balanced workload could be achieved in this way.

Planning tool manages the complexity of efficient allocation

The challenge with a large remote tower centre is the optimal allocation of the different airports to the air traffic controllers and the available workstations. "This complex task requires automatic planning tools to support the supervisor of a centre in devising the most suitable distribution of task load," says Jakobi.

As part of the EU-funded SESAR research project 'Digital Technologies for Tower' (PJ05-W2 DTT), DLR, Frequentis AG and the Lithuanian and Polish air navigation services 'Oro Navigacija' and 'PANSA' have developed the concept and necessary planning tools for the remote control of several airports, implemented them in prototypes and tested them. The role of the supervisor position is key. This person monitors and distributes the task load to individual controllers and ensures that they are not underloaded or overworked. The planning tool combines various data, such as the number of arriving and departing aircraft and the expected traffic mix. The supervisor views the processed data and thus has a comprehensive overview of the current and future situation. In the event of poorly balanced task loads, the tool suggests possible solutions. If, for example, a controller is predicted to face an excessive workload, the planning tool helps the supervisor find an additional spare workstation and a suitable controller from the pool to assist.

Initial feedback from the participating controllers shows the viability of the concept. "I am convinced that such remote tower centres represent the future," says Jakobi. "They are the natural evolution of conventional towers at airports. This validation has shown the concept's potential."

Press Release - Frequentis - 3 March 2022: Press release on multiple remote towers

The project received funding from the SESAR Joint Undertaking as part of Horizon 2020, the European Union Framework Programme for Research and Innovation (grant number 874470).