A leading international airline has cancelled all flights to an Estonian airport until June at the earliest due to “GPS interference in the area”.
Finnair says that its normal services to Tartu, the cultural hub of Estonia, cannot operate safely because the approach is dependent on Global Positioning System (GPS) technology.
In a post on X, the Finnish airline said: “We’re suspending our flights to Tartu from 29 April until 31 May.
“The approach methods currently used at Tartu Airport are based on a GPS signal and GPS interference in the area affects the usability of this method.”
Russia is widely suspected of jamming or spoofing GPS signals close to its frontiers. Tartu airport is around 40km (25 miles) from the Russian frontier.
Finnair says it is working on “an alternative approach solution that doesn’t require a GPS signal”.
Last week, two Finnair flights had to divert back to Helsinki after GPS interference prevented the approach to Tartu. On both 25 and 26 April, the evening flight from the Finnish capital abandoned the planned landing and turned around.
Finnair is the only airline operating international flights to and from Tartu.
Jari Paajanen, the carrier’s operations director, said: “The systems on Finnair’s aircraft detect GPS interference, our pilots are well aware of the issue, and the aircraft have other navigation systems that can be used when the GPS system is unserviceable.
“Most airports use alternative approach methods, but some airports, such as Tartu, only use methods that require a GPS signal to support them. The GPS interference in Tartu forces us to suspend flights until alternative solutions have been established.
“We apologise for the inconvenience the suspension causes to our customers.”
Finnair says GPS interference has increased significantly since 2022. The airline’s pilots have reported interference near Kaliningrad – the slab of territory, about the size of Yorkshire, that is a Russian exclave between Lithuania and Poland.
GPS interference has also been encountered in the Black Sea, the Caspian Sea and the eastern Mediterranean. It is perpetrated in two forms: jamming, which makes it impossible for pilots to know their precise location using GPS; and spoofing, whereby the aircraft’s systems are tricked into representing the wrong position.
The airline says: “Typically, GPS interference does not affect flight routes or flight safety, as pilots are well aware of it and aircraft have alternative systems in place that are used when the GPS signal is interfered with.”
Last week Downing Street said an RAF plane carrying the defence secretary, Grant Shapps, was targeted by GPS interference for 30 minutes over the Baltic.