Incidents of interference with the GPS signals of Finnish aircraft are likely part of Russia's hybrid strategy and could even be training exercises for a state of war, according to Jukka Savolainen, director of the Helsinki-based European Centre of Excellence for Countering Hybrid Threats (Hybrid CoE).
Savolainen told Yle that Finnish society should be prepared for much more intense interference, and air traffic should use multiple satellite positioning systems to ward off such attacks.
Yle's investigative journalism unit MOT reported earlier this week that Finnish air traffic was extensively disrupted in March last year following Russia's invasion of Ukraine in February.
For example, the seemingly deliberate jamming of GPS signals prevented aircraft from landing at Savonlinna airport, located in the east of Finland less than 100km from the Russian border.
One military specialist, retired Major Marko Eklund, told MOT that there are several Russian military bases housing electronic warfare forces near Finland, and their mission is to jam communications, such as GPS signals from aircraft.
"In the areas where that interference had been detected, there is a team from across the border whose job it is to cause it," Eklund noted.
Russian units practice hybrid influencing
Jukka Savolainen confirmed to Yle that MOT's information regarding the aircraft interference is credible.
"I would not dispute any part of the information," he said, adding that it is still not clear whether the jamming was deliberately aimed at Finland or a side effect of Russian military training.
Russian electronic warfare forces might train for a situation where electronic air defence is switched on in order to prevent flights into Russia, Savolainen explained.
"If tensions are heightened and Russia begins to fear unauthorised drone flights or even missiles, there will be widespread disruption [to GPS signals]," he said.
Similar air traffic disruptions have been frequently observed in the Black Sea, Savolainen further noted, near the villa of Russian President Vladimir Putin.
Finland must be prepared for "more serious" interference
Although the incidents involving Finnish aircraft last year should be taken seriously, Savolainen noted that the level of hybrid influencing involved was small compared to what could happen.
"If signal jamming covered a wide area and prevented navigation near an airport, pilots would no longer know where their own plane was or other planes were. It could force the suspension of all air traffic," Savolainen said.
He added it is also possible that, in a crisis situation, jamming devices could be placed in properties acquired by Russian citizens, making it more difficult to shut them down.
The same devices can also be used to jam mobile phone traffic, for example.
However, Savolainen also told Yle that the Finnish Defence Forces are of course prepared for such situations, and that deliberate electronic jamming on Finnish territory can be considered an infringement of territorial integrity, so military force can be used against it if necessary.
"Society as a whole should prepare for more severe interference than we are currently experiencing," Savolainen said.
He recommended that other satellite positioning systems, such as the EU's Galileo, should be introduced on aircraft alongside the American GPS system.
Different positioning systems use different frequencies, and therefore jamming them is not as easy as jamming just one system.
Hybrid attacks began even before war in Ukraine
MP Antti Häkkänen (NCP), chair of Parliament's Defence Committee, told Yle that incidents of signal jamming in Finland have not particularly increased since Russia's invasion of Ukraine last February.
"Finland, like the rest of Europe, has been the target of this type of interference in the past. It is likely to be bullying and harassment, causing trouble and problems in many sectors," Häkkänen said, but said he did not wish to comment on whether Russia has engaged in such activities in Finland.
"Of course, it's no secret that Russia is known to have the electronic warfare forces and know-how to do this," he said.
Häkkänen also said he did not wish to comment on whether Finland has reacted in any way to these incidents.
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