Aircraft flying over the Baltic region have reported a growing number of missing or false GPS signals. The likely cause of these blackouts is believed to be GPS jamming, and Russia is seen as the most probable culprit. These jamming incidents have been happening regularly since the beginning of the war in Ukraine in 2022. The jamming seems to be centred around Russia's Kaliningrad exclave, which is a crucial military area for Moscow.
“Russia is regularly attacking the aircraft, passengers, and sovereign territory of NATO countries,” said Dana Goward, president of the U.S.-based Resilient Navigation and Timing Foundation, a GPS users lobby group. “It is a real threat,” Goward warned. “There is one instance of accidentally jamming we know of that almost resulted in a passenger aircraft impacting a mountain,” referring to a case reported by NASA in 2019.
The EU Aviation Safety Agency (EASA) is looking into the issue, but so far regulators say that the GPS problems are not a danger to flights.
Interference cases reported by pilots “have been increasing steadily since January 2022,” said Eurocontrol, the European Organization for the Safety of Air Navigation, which receives reports from pilots through its voluntary incident reporting system EVAIR. During the first two months of 2024, EVAIR recorded high increases in GPS outage reports. In absolute figures we received 985 GPS outages compared with 1,371 for the whole of 2023," Eurocontrol said, adding that there were almost seven times more incidents in the first two months of this year compared to the first two months of 2023.
Recently, an open source intelligence profile on X, formerly Twitter, named Markus Jonsson said that GPS jamming in the Baltic region had been going “for 47 consecutive hours making this the longest run ever” affecting “1,614 unique aircraft,” but the actual number could be higher.
EASA hasn't been able to confirm the Russian origin of the interference or whether the jamming is intentional. “Due to the locations affected, it is very likely that the activity is conflict-related, with the impact on civil aviation being a side effect. However EASA can’t say who is responsible,” said EASA spokesperson Janet Northcote.
But Goward called the incidents “absolutely deliberate,” adding: “The war zone in Ukraine is much too far away for interference in the Baltic to be spillover.”
EASA and the International Air Transport Association (IATA) held a joint workshop in January on the subject. At the time, EASA Acting Executive Director Luc Tytgat said the agency has seen a “sharp rise in attacks on these systems, which poses a safety risk.”
However, Northcote, speaking this week, said: “Currently, the situation is not considered unsafe, moreover, the awareness has significantly improved among the crews, thanks to diverse safety promotion actions from airlines, aircraft manufacturers and regulators.”
Jamming is considered to be very easy to do because it only takes a very, very weak signal to make a GPS receptor go dark, and tools capable of jamming signals can be bought online. Another hack called spoofing displays a false position of the aircraft. “Spoofing is a bit harder than jamming,” but with the right tools “a reasonably competent hobbyist can do it. We have recently seen spoofed aircraft almost accidentally fly into Iranian airspace without clearance, which could have resulted in a shoot down,” Goward said.
“Typical regions where GPS interference has been reported include the Baltic and Kaliningrad area, around the Black Sea, the Caspian Sea as well as the eastern Mediterranean,” said Jenni Kiiski, spokesperson for Finnair, one of the airlines most affected by GPS jamming. Many of its flights go south from Helsinki over the Baltic Sea and pass near Kaliningrad, she said.
When GPS interference disrupts airBaltic flights, “the route taken and the location shown on the small cabin screens visible to passengers, as well as possibly on the website Flightradar24, may in exceptional cases differ from the actual route,” Kristops said.
In mid-March, a military plane carrying British Defense Secretary Grant Shapps was hit by GPS jamming on its way back from Poland.
EASA hasn't been able to confirm the Russian origin of the interference or whether the jamming is intentional. In the wake of the Oct. 7 Hamas attacks, Israel has been jamming and spoofing GPS signals on its border with Lebanon to protect its territory from Hezbollah rocket attacks. Recently, Israeli jamming caused problems for Lebanese civil aviation, with reports of planes headed for Beirut being forced to turn back because of the signal blackout.
Although the jamming may be disconcerting, it doesn't pose a significant safety risk, said Stuart Fox, director of flight and technical operations safety at airline lobby IATA. “An aircraft can safely navigate the globe without GPS.”
“I started flying in the late 80s when there was no GPS and we used to fly over the globe,” he said, adding that modern aircraft integrate different navigation sources. “When it’s over land, it uses ground-based navigation sources; when it’s over the oceans, it uses inertial reference systems.”
Pilots can still find their way without GPS, Goward acknowledged, but not having the system working properly “makes pilot and air traffic controller workload go up, and the chances of mistakes go up.”
Goward linked the most recent spate of jamming in the Baltic to “Sweden approaching and gaining membership in NATO, and more directly to a US Aegis anti-missile system being installed and activated in northern Poland.”
He said the Polish system went live on Dec. 15. “Interference began the same day along the northern Polish border and through the strategic Suwałki Gap,” he added, referring to a narrow piece of Polish and Lithuanian territory separating Kaliningrad from Russian ally Belarus.
Asked if EASA will apply safety restrictions on commercial air traffic, Northcote said: “It’s not for EASA to impose such limitations, as this is a state responsibility,” adding: “EASA is continuously monitoring the events to make sure that no unsafe situation develops.”
