Everything in Sight, Even From Afar

After several research and development programs, the time has come: the first “Remote Tower” in Leipzig enables air traffic controllers to coordinate flights at Saarbrücken Airport remotely – more are to follow.
Binoculars are still an indispensable piece of standard equipment in every airport tower, but not any more at Saarbrücken International Airport. For more than six months now, daily operations have been remotely monitored from the grounds of Leipzig airport, 450 kilometers away, where DFS Deutsche Flugsicherung GmbH operates a Remote Tower Control Center. From here, the air traffic controllers have a clear view of the traffic in Saarbrücken in the air and on the ground, even though they cannot see it directly out of the window. Instead of looking through traditional binoculars, the controllers use a multitude of monitors displaying images from high-resolution video and infrared cameras. According to DFS, Saarbrücken is currently the world’s largest airport that is monitored remotely during day-to-day operations. After an introductory phase of only four weeks, the Remote Tower Control Center was put into regular operation at the turn of 2018/2019.

A network of several cameras provides the controllers with a 360-degree panoramic image, and they can freely choose the section of the image to focus on. The cameras in Saarbrücken can be swiveled and tilted to a large extent and zoomed to display even distant details.

Infrared technology provides air traffic controllers with a significantly improved view of the apron and the runways, especially in darkness. A new IT system, the Remote Tower Control System, also provides them with valuable support. It automatically detects all flight and taxiing movements and highlights the aircraft on the ground and in the air on the monitors. Aircraft taking off and landing can be tracked manually or automatically by the cameras; all optical functions are designed redundantly for safety reasons.

“Our Remote Tower Control System is a key innovation and an example of how new digital technologies can be used in the aviation sector,” explains DFS CEO Professor Klaus-Dieter Scheurle. “We are improving our efficiency while maintaining the high standards of safety DFS requires.” According to him, the system is unique worldwide and “establishes a new standard in remote tower technology”.

Air traffic controllers outside the tower having no direct line of sight to the aircraft has been common practice for decades. This is how DFS monitors flight movements throughout German airspace at the four major control centers in Langen, Bremen, Munich and Karlsruhe. “It’s a logical next step to control take-offs and landings remotely,” says Professor Scheurle.

„With our system, we are now able to control an international airport around the clock from a remote location for the first time.“

PProfessor Klaus-Dieter Scheurle,
CEO of DFS Deutsche Flugsicherung GmbH, Langen

With the remote tower technology, DFS is not only aiming to save costs while maintaining a high level of security. Above all, they also want to be able to deploy air traffic controllers more flexibly. “Until now, this solution was only an option at very small airports with low air traffic volumes,” says Scheurle. “With our system, we are now able to control an international airport around the clock from a remote location for the first time.”

The development partner for the remote tower system was the Austrian technology company Frequentis, while the video and infrared sensors were provided by the German Rheinmetall Defence Electronics group.

The system has been developed over the last four years, and the national and international marketing campaign is now being launched. DFS subsidiary DFS Aviation Services GmbH and Frequentis have founded their own company, Frequentis DFS Aerosense GmbH, for this purpose.

Incidentally, Remote Tower technology is not a job killer: ten air traffic controllers from Saarbrücken have moved to Leipzig. Following the positive experience with Saarbrücken, DFS plans to transfer control of the airports in Erfurt and Dresden to Leipzig in the coming years. Appropriate training should enable air traffic controllers to obtain authorization to work at all three airports in the medium term.

The German Aerospace Center (DLR) is also intensively involved in remote monitoring, especially of smaller airports, and is conducting research into an innovative Multiple Remote Tower concept. In future, this too should allow air traffic controllers to manage not just one, but several airports at the same time from a distance. There are 37 international partners involved in the project within the framework of the EU “Horizon 2020” research and innovation program.

„In more complex traffic situations, one, two or more controllers may manage one airport, while in less intensive conditions, a single controller may be responsible for one, two or more airports.“

Jörn Jakobi,
DLR project coordinator of the European research project
“PJ05 Remote Tower for Multiple Airports”

Jörn Jakobi is convinced that, “the latest results of our test campaign have shown that a ‘multiple’ solution could become a viable concept in the near future.” He is DLR project coordinator of another European research project called “PJ05 Remote Tower for Multiple Airports”. The project is paving the way for a paradigm shift in air navigation services, allowing air traffic control at airports to be decoupled from location and conventional tower buildings.

However, in order to fully exploit the advantages of the remote tower concept, the centers would have to be connected to more than one airport, says Jakobi. “This enables a much more efficient allocation of airports to air traffic controllers. The controllers work flexibly at the airports where there is more traffic. In more complex traffic situations, one, two or more controllers may manage one airport, while in less intensive conditions, a single controller may be responsible for one, two or more airports.”

Photos and videos from DFS and DLR
Text by Behrend Oldenburg