Our glossary contains frequently used terms and acronyms together with their explanations.


Flying is the safest way to travel, because it has the lowest number of accidents per passenger-kilometre of all means of transport. This is not to say that mistakes do not happen in air traffic.  However, wrong decisions are systematically recorded and analysed to prevent similar mistakes from happening in the future. Safety is also our top priority at DFS.

Passengers boarding an aircraft at a German airport have no cause for concern. The fact that flying is safe not only in Germany but throughout Europe is reflected by the statistics compiled by the International Air Transport Association (IATA). These put Europe among the safest regions in terms of air traffic. It is largely at the discretion of a car driver to decide whether to drive quickly or slowly, whether to tailgate or leave enough space between his car and the car in front. Air traffic, however, is another story. All flights under instrument flight rules are controlled by air traffic controllers. Whether during take-off, landing or overflight – the DFS controllers ensure that all aircraft in German airspace keep sufficient distance from each other. The minimum vertical separation between two aircraft has to be at least 1,000 ft (approximately 300 metres), while the prescribed horizontal separation is between three and eight nautical miles (5.6 to 14.8 kilometres). When aircraft on approach-to-land are being guided into the airport by the controller like pearls on a string, the minimum separation is three nautical miles. Some airports still apply two or two-and-a-half miles (3.7/4.6 kilometres), depending on the certified procedure.

There are rarely any consequences if a car driver gets too close to the car in front of him, unless he is caught by the police or the driver in front brakes suddenly. But there are consequences in air traffic. Every infringement of the separation minima in the air and every potentially dangerous situation on the ground is recorded and analysed. It is the task of the safety management system of DFS to conduct an analysis.