GPS signals for flight navigation and incorrect location and altitude data are being disrupted daily in the Baltic Sea region by pilots in Europe. The clues point to Russia.
At Copenhagen airport, pilot Oliver Kviter inspects his plane before takeoff. He has to take passengers to the island of Bornholm in the Baltic Sea, and the plane is full. Before departure, he and the co-pilot entered the route into the on-board computer's memory - all they had to do was follow it.
This is possible through the GPS satellite navigation system, writes ARD and explains: the computer devices on board the aircraft communicate with satellites in space and thus determine the position. “Satellite navigation is extremely important”, says the pilot. Thanks to it, the commanders know where they are at any moment.
However, in the Baltic Sea region there are constant problems with GPS signals, as Oliver Kwieter and other pilots shared with the German media. There is interference, navigation via satellites often does not function. In such cases, the commander must receive instructions from the air traffic controller via radio. "Then we have to follow them until the system works again or even until landing," the pilot explains.
Pilots report disruptions every day
Kviter says he has encountered such disruptions three or four times in the past five years, but adds: "I know from colleagues who regularly travel to Finland and the Baltic countries that for them disruptions are an everyday occurrence."
Data from Germany shows that there are still "small double-digit numbers" of such disruptions reported by air traffic controllers every day, which requires even more attention from them. "We are currently in control of the situation," Morten Grant, head of the navigation department at the German air traffic control service, told ARD. If the number of jamming increases even more, it will lead to an overload of air traffic controllers.
Russia's hybrid war
Since the planes also report the recorded jamming to ground stations, the companies that collect the data can identify the areas with the most problems - such as the Baltic Sea. In addition, researchers from the University of Gdynia have managed to locate a large jamming installation in Kaliningrad.
In front of ARD, representatives of the German Navy also identified Russia as the source of the signals interfering with the pilots' work. They apparently originate both from land and from Russian ships. The EU High Representative for Foreign Affairs and Security Policy Kaia Kallas also spoke about “hybrid warfare”.
According to security expert Nico Lange, this is about “testing the gray areas”. Russia is deliberately trying to manipulate the signals - for it, the interference "is certainly part of the war", says Lange.
Many pilots are worried
The situation is causing concern among pilots. In a 2024 study, for which 2,000 pilots were surveyed on the topic of interference, more than two-thirds admitted that they were "very or extremely worried". The questions were not related to GPS interference in general, but only to a specific type that is observed in the Baltic Sea region.
This type of interference simply misleads pilots - not only is the reception of data blocked, but also false signals are deliberately sent to mislead the planes. The on-board computers suddenly start to show that the plane is somewhere else or at a different altitude than it actually is, and this can have serious consequences. "If the GPS position is falsified, this can lead to a large number of misleading warnings," explains Niklas Ahrens, who deals with these problems at the pilots' union "Cockpit", to ARD.
False warnings in the cockpit
This is mainly about the so-called extended warning system when approaching the ground. Its purpose is to prevent a plane from crashing into a mountain, for example. Through GPS interference, this system can issue false warnings such as "Obstacle ahead! Climb up!".
This is an urgent warning that pilots usually only hear in simulators. "In flight, these types of warnings are usually misleading. And the system should be turned off," Ahrens explains. This avoids false warnings, but it also leaves a safety net that would protect the aircraft in certain circumstances.
The ARD journalists spoke to a number of major airlines that fly in the Baltic Sea region. “Lufthansa” states that GPS spoofing constitutes “a serious violation of civil aviation security”. The Polish airline LOT responds that temporarily disabling the system still provides greater security than following warnings caused by false location data.
“This should not be accepted as the new normal”
But how to respond to disruptions in aviation? Kaia Kallas believes that the issue should also be considered by NATO. “Of course we need to do more in this regard and not accept it as the new normal.”
Security expert Nico Lange's view is that the disruptions in the Baltic Sea region may be more than just a provocation. Electronic warfare is a means of “preparing a battlefield”. The fact that there are so many cases in the Baltic Sea could mean that “Russia is at least considering, and perhaps planning, military operations in the region,” he says.