The Federal Ministry for Digital and Transport, the Federal Supervisory Authority for Air Navigation Services and DFS Deutsche Flugsicherung GmbH have launched extensive measures in recent months to improve the compatibility of air navigation services and wind energy. The common goal was to ensure the undisturbed operation of air traffic control systems while also seeking to take energy policy issues into account, i.e. to ultimately make more space available for onshore wind turbines. Within the framework of the research project WERAN (interaction of wind turbines and radar/navigation) funded by the Federal Ministry for Economic Affairs and Climate Action , the Physikalisch-Technische-Bundesanstalt (PTB) defined the essential aspects for a recalculation of protection areas around air navigation facilities. At the same time, the measures now taken by air navigation services implement important parts of the key points that were agreed by the Federal Ministry of Transport and the Federal Ministry for Economic Affairs and Climate Action on 5 April 2022.

Federal Minister Dr Volker Wissing said: "Wind power is of great importance for enabling a climate-friendly energy supply in our country. As we seek to expand wind energy more quickly, we have made it possible within a very short time to reduce the distance between wind turbines and air traffic control and meteorological systems on the basis of the latest scientific findings. We have thus removed a significant obstacle to the expansion of onshore wind power. I would like to thank everyone involved who, with great dedication and constructive exchange, has worked to reconcile the different requirements."

Federal Minister Dr Robert Habeck said: "More areas for wind energy while ensuring the reliability of radio navigation – this is a giant step forward and crucial for the expansion of wind power. The successful cooperation with the aviation authorities and the Ministry of Transport is a very good example of how we are removing obstacles at all levels to accelerate the expansion of renewable energy."

System protection areas to be reduced

In April of this year, the Federal Ministry for Economic Affairs and Energy and the Federal Ministry for Digital and Transport agreed to reassess the system protection areas of air traffic control systems based on new scientific findings gained from the WERAN project. On the basis of new criteria, DFS now has the opportunity to reassess the protection areas of the Doppler rotating beacons (DVOR) and to determine whether they can be reduced to a radius of seven kilometres proposed by PTB. Only within this radius do air traffic control aspects have to be taken into account for construction projects. The reassessment started on 1 August 2022 and is expected to be completed by the end of 2022. The results already available have allowed for the reduction of the protection areas of DVOR Klasdorf, DVOR Gedern and DVOR Fulda (as early as 1 August 2022). DFS expects that the reduced distance of seven kilometres will also be sufficient in many other cases, thus removing one of the obstacles to the planning of wind turbines.

New calculation formula for CVOR

The potential disturbance of the navigation information provided by the radio beacon that may be caused by wind turbines, the so-called angular error, is determined using a calculation formula. DFS and PTB were able to develop a new formula that enables more precise predictions. In the case of the more robust Doppler rotating beacons, a jointly developed formula has already been used since 2020 and since then, the approval rate has increased to over 90 per cent. The new CVOR calculation formula, which is expected to be operational from the end of September 2022, is also projected to lead to a higher approval rate for conventional radio beacons (CVOR).

Acceptance of higher angular errors

By reassessing the performance requirements necessary for area navigation on the one hand and technical modifications to the navigation systems on the other, a higher angular error caused by wind turbines, for example, can now be accepted and thus the available error budget can be increased from a current 1.0° up to 1.5° or, in some cases, be more than doubled to 2.1, depending on the turbine type. This allows the construction of additional wind turbines in the protection areas of rotating radio beacons.

Dismantling and conversion of rotating radio beacons

As part of the introduction of modern, increasingly satellite-based navigation methods, DFS is currently reviewing around 2,600 flight procedures across the whole of German airspace. The new procedures enable radio beacons to be dismantled in many places. Since 2002, 17 beacons have already been dismantled; of the 51 beacons currently owned by DFS, a further 20 are expected to be dismantled by 2032.

In addition, through the support provided by the Federal Ministry for Economic Affairs and Energy, it has been possible to convert eight CVORs into DVORs which are less susceptible to interference.

DFS, Kristina Kelek,, tel.: 06103-707-4161
BAF, Eva Ramos,, tel.: 06103-8043145
BMDV, Tim Alexandrin, , tel.: 030-18300-7200
BMWK, Susanne Ungrad,; tel.: 030-18615-6133
PTB, Jens Simon,, tel.: 0531-592-3005

DFS Deutsche Flugsicherung GmbH is a federally owned company under private law with around 5,600 employees (as at 31 December 2021). DFS ensures safe and punctual flight operations. In peak years, around 2,200 air traffic controllers have guided more than three million flights through German airspace – as many as up to 10,000 a day. The company operates control centres in Bremen, Karlsruhe, Langen and Munich as well as towers at the 15 international airports in Germany. The subsidiary DFS Aviation Services GmbH markets air traffic control-related products and services and is responsible for air traffic control at nine German regional airports and at London Gatwick and Edinburgh airports. DFS is playing a major role in the integration of drones into air traffic and has founded the joint venture Droniq GmbH with Deutsche Telekom. The subsidiary R. Eisenschmidt GmbH sells publications and products for general aviation, Kaufbeuren ATM Training (KAT) trains military air traffic control personnel, and the joint venture FCS Flight Calibration Services offers flight calibration services.