DFS Deutsche Flugsicherung: roles, control centers and organization

Every jet you photograph at the fence has passed through several pairs of hands you never see: the tower that gives the takeoff clearance, the approach control that puts it on final, and the center that guides it across Germany. Behind all of this stands DFS Deutsche Flugsicherung. This guide explains how the state-owned company is organized, which control center handles which airspace, why in Saarbrücken no controller sits in the tower anymore – and where DFS meets you as a spotter every day.

DFS in one paragraph

DFS Deutsche Flugsicherung GmbH is Germany’s national air navigation service provider. It is 100 percent owned by the federal government, is headquartered in Langen in Hesse, just a few kilometers from Frankfurt Airport, and took over the duties of the Federal Air Navigation Services Agency (Bundesanstalt für Flugsicherung) on January 1, 1993. Legally it is a company vested with sovereign powers: a privately organized firm that performs sovereign tasks of the federal government. According to DFS, its controllers handle every flight operating under instrument flight rules (IFR) in German airspace – civil and military, around the clock, 365 days a year.

By its own account, DFS employs around 5,900 people at 19 locations. In addition to the roughly 2,200 controllers, that includes around 900 technicians and engineers who develop and operate radar, radio and flight data systems, plus flight information officers, instructors and administration.

How the work is divided: tower, approach, center

A scheduled flight from Hamburg to Munich changes its point of contact several times along the way – the individual stations from delivery to center are covered in detail in the article Delivery, ground, tower, approach, center. Air traffic control is organized in levels, and each level has its own airspace and its own frequencies.

Level	Responsibility	Where the controllers sit	Typical callsign on the radio
Ground control / apron	Taxiing between the stand, taxiways and runway	in the tower or in an apron control of the airport	“… Ground”, “… Apron”
Aerodrome control (tower)	Runways, traffic pattern, control zone	in the tower at the airport or in the remote tower	“… Tower”
Approach control	Arrivals and departures around the airport	usually in a control center	e.g. “Langen Radar”, “Bremen Radar”
Area control (center)	En-route flight in the lower and upper airspace	control centers Langen, Bremen, Munich, Karlsruhe	e.g. “Munich Radar”, “Rhein Radar”
Flight information service (FIS)	Advisories for VFR pilots, no separation	Langen	“… Information”

Tower: the part you see

According to DFS, tower controllers manage traffic on the apron, on the runways and in the immediately surrounding airspace. They have direct visual contact with the aircraft, and in fog and at night a ground radar helps them. When you hear an airliner get “cleared for take-off” at the fence, that clearance comes from the tower. Which runway is used for takeoffs and landings is decided by the tower depending on the wind – more on that in the guide Understanding the runway direction in use at an airport.

Incidentally, the DFS tower does not direct every taxi movement. At large airports such as Frankfurt or Munich, an apron control run by the airport operator handles taxi guidance on the apron before the aircraft is handed over to the tower.

Approach control: the invisible funnel

Between the en-route phase and the runway lies approach control. It sorts the arriving aircraft into a sequence, assigns altitudes, headings and speeds and puts them on final approach, usually onto the instrument landing system. How the ILS works is explained in the article ILS approach explained. The spacing between aircraft depends on radar minimum separation and wake turbulence categories – which is why the aircraft behind an A380 land with a bigger gap, see Wake turbulence and separation.

For the big airports in Germany, approach control is usually not located in the tower but in the responsible control center. On the radio you therefore hear it under the name of the center. The fixed routes on which aircraft arrive and depart are the SIDs and STARs, explained in the article SID and STAR. When things get tight, approach control sends aircraft into a holding pattern.

Center: the en-route phase

The en-route phase is handled by the center controllers in the control centers. According to DFS, they control every IFR flight over Germany. The airspace is divided into many sectors for this, each with its own frequency. An aircraft is passed on from sector to sector – you don’t see that on the flight tracker, but you certainly hear it on the radio when the crew switches to a new frequency.

The four control centers

DFS operates four center facilities. The division follows altitude at its core: three centers handle the lower airspace, one the upper airspace.

• Langen: At the company headquarters on the DFS campus, the center handles the lower airspace over central Germany, including the area around Frankfurt Airport. The campus is also home to the AIS center, the air traffic control academy, the research center and the technology center.
• Bremen: The center and tower facility at Bremen Airport handles the lower airspace in the north and northeast – you also hear its callsign around Hamburg and Berlin.
• Munich: The center right at Munich Airport handles the lower airspace in southern Germany.
• Karlsruhe: The control center in Karlsruhe monitors the upper airspace. According to DFS, the boundary is at roughly 7,500 meters (flight level 245), in places higher over southern Germany; above it runs most of the overflight traffic, that is, the jets you only see as contrails.

There is one special feature in the north: civil traffic in the upper airspace over parts of northern Germany is handled by the Eurocontrol center in Maastricht; DFS provides staff there for the military air traffic services. What else Eurocontrol does is covered in the article Eurocontrol explained.

Towers at 15 airports – and two of them without a tower

At Germany’s 15 international airports, DFS provides aerodrome control: Berlin Brandenburg, Bremen, Dresden, Düsseldorf, Erfurt-Weimar, Frankfurt, Hamburg, Hanover, Cologne/Bonn, Leipzig/Halle, Munich, Münster/Osnabrück, Nuremberg, Saarbrücken and Stuttgart. You can find profiles of many of these airports on our site, for example Munich Airport, Düsseldorf Airport or Berlin Brandenburg Airport.

Two of these 15 airports no longer have a staffed tower. DFS controls Saarbrücken Airport and Erfurt-Weimar Airport from the Remote Tower Control Center in Leipzig. Cameras at the airports deliver a panoramic picture to high-resolution screens, while the controllers work hundreds of kilometers away. The center at Leipzig/Halle Airport has been in operation since December 2018, first for Saarbrücken; Erfurt-Weimar was added in April 2022.

What happens at the other airports

Outside the 15 international airports, DFS is not automatically in the tower. Since a change to the Basic Law in 2009, air navigation services may also be provided by foreign organizations approved under European law. At regional airports with a control zone, this is why the subsidiary DFS Aviation Services, which according to the company serves nine German regional airports, sometimes takes over, and sometimes another provider. How the neighbors organize this is shown in the article on Austro Control and Skyguide.

More than controllers: FIS, AIS and technology

A large part of DFS’s work has nothing to do with clearances at all.

• Flight information service (FIS): VFR pilots who are not being guided by air traffic control can call FIS on dedicated frequencies. It is based in Langen, gives weather and traffic advisories and helps with navigation, but expressly provides no separation. Which airspace class has which rules is explained in the article Airspace classes A to G.
• Aeronautical Information Service (AIS): The flight information officers in the AIS center in Langen accept flight plans and support pilots in their preparation. The aeronautical information, which includes NOTAMs, also runs through this service – how to read them is shown in Reading and understanding NOTAMs.
• Air traffic control technology: DFS develops and operates radar systems, radio stations, navigation aids and flight data processing itself. This also includes the regular flight inspection of instrument landing systems.
• Military air traffic control: DFS handles civil and military flights under instrument flight rules together. Through its subsidiary Kaufbeuren ATM Training, which took over the training from the Bundeswehr (German armed forces), it also trains military air traffic control personnel.

Subsidiaries and holdings

DFS has built up a number of companies around its core business. Three are of particular interest to spotters:

• DFS Aviation Services: markets air traffic control services in Germany and abroad and operates towers at regional airports. A British subsidiary is responsible for air traffic control at Edinburgh Airport.
• Droniq: a joint venture with Deutsche Telekom for drone-related services. Where you may fly a drone in Germany is shown in the article Geozones and the dipul map.
• FCS Flight Calibration Services: a joint venture with Skyguide and Austro Control that carries out calibration flights – the aircraft circling low over runways and approach lighting are often a small highlight for spotters.

From BFS to GmbH: a short history

Until the end of 1992, civil air traffic control in the Federal Republic was the responsibility of the Federal Air Navigation Services Agency (Bundesanstalt für Flugsicherung, BFS), founded in 1953. With the conversion into DFS on January 1, 1993, air traffic control was moved into a private-law form but remained owned by the federal government. An attempt to sell part of DFS to private investors failed in 2006: Federal President Horst Köhler did not sign the law because he considered it incompatible with the Basic Law. In 2009, Article 87d of the Basic Law was amended, and since then it has also permitted foreign air navigation organizations approved under European law.

The headquarters has been in Langen since April 2002. How air traffic control as a whole came about – from the first light signals at the airfield to radar and data link – is told in the article on the History of air traffic control.

Oversight and funding

DFS is supervised by the Federal Supervisory Authority for Air Navigation Services (Bundesaufsichtsamt für Flugsicherung, BAF), also in Langen. It is funded through fees: for the en-route phase, aircraft operators pay en-route charges that are collected centrally via Eurocontrol; for arrivals and departures at the international airports, DFS charges fees directly. The level is set by the Federal Ministry of Transport, and cost planning follows European rules in multi-year periods.

Where you meet DFS as a spotter

You don’t have to be a radio scanner pro to notice the work of air traffic control at the spot. A few typical situations:

When listening in, note this: what is allowed in Germany and what is not, especially when passing on what you have heard, is summarized in the article Listening to aviation radio: the legal situation. And if you wonder why an airline is called on the radio by a completely different name than the one on the tail, the article Callsign and flight number helps.

The DFS campus as an excursion destination?

The DFS campus in Langen is an operational site and not an excursion destination – visitors must identify themselves there with an ID card or passport. Spotters have a better view nearby anyway: from Frankfurt Airport, for example at the Zeppelinheim viewing platform, you see the traffic that the colleagues in Langen are sorting. And at the Leipzig/Halle observation deck you stand at the airport from which Saarbrücken and Erfurt are controlled.

Becoming a controller at DFS

DFS trains its own new recruits, at the air traffic control academy in Langen. According to the company, around 350 prospective controllers are in training, plus around 130 dual-study students in subjects such as air traffic control engineering or computer science. What the selection process, training and daily work look like is explained in the article Becoming an air traffic controller.

Conclusion

DFS Deutsche Flugsicherung is the invisible infrastructure behind every picture at the fence. As a state-owned GmbH headquartered in Langen, it runs German airspace from four control centers – Langen, Bremen and Munich below, Karlsruhe above – and provides aerodrome control at the 15 international airports, two of them by remote tower from Leipzig. If you can tell tower, approach and center apart, you understand runway changes, holding patterns and delays much better and hear on the radio what comes next.