GPS disruptions have prevented Finnair planes travelling from Helsinki to Tartu, Estonia, from landing for the past two nights.
Instead of landing, the planes returned to Helsinki Airport.
According to Finnair, landing at Tartu Airport requires the use of GPS signals.
Finnair spokesperson Päivyt Tallqvist said that both flights departing around midnight on Thursday and Friday had to return to Helsinki Airport.
GPS interference is a relatively common phenomenon, and it doesn't usually warrant flights turning back, according to Tallqvist.
Airports generally use multiple systems for approach and don't necessarily rely on GPS signals.
"Tartu Airport is one of the few that has no other systems," she explained.
Friday's daytime flights to the city did not experience GPS interference.
Finnair began operating flights to Tartu Airport at the end of last month.
GPS disruptions during flights have increased in Finland since 2022, with Russia often suspected to be behind the interference.
This spring the Finnish Transport and Communications Agency (Traficom) said it received more than 18,000 flight safety notifications from aviators in 2023 — more than double the average volume of such reports during 2013-2022.
Estonian news outlets ERR and Postimees were the first to report the news.
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