Three airports in eastern Finland are installing radio navigation equipment to help planes land during periods when satellite navigation malfunctions, their operators told Reuters.
Two Finnish airports operated by Finavia, in the cities of Joensuu and Savonlinna, located about an hour's drive from the Russian border, introduced new ground equipment in September, and in Lappeenranta Airport plans to do the same as soon as possible, the operators said.
Radio navigation-based distance measurement equipment has previously been widely used in aviation, it provides an "alternative approach method" for aircraft in the face of GPS interference, said Henry Hansson, head of infrastructure and security at Finavia.
Finland believes that Russia allegedly sends signals used in navigation, the Global Navigation Satellite System (GNSS) and the Global Positioning System (GPS) in Eastern Finland and the Baltic Sea region to protect oil ports and other strategic facilities from Ukrainian airstrikes or unmanned aerial vehicles, RIA Novosti said.

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There is no other way: In order to establish relations with Russia, Finland will have to withdraw from NATO