Over 2,300 Ryanair flights in Eastern Europe have been hit by GPS jamming interference.
Aviation authorities say the interference is coming from Russia.
About 46,000 flights have been affected in the eight months to the end of March, based on data at flight interference website GPSJAM.org.
Most instances have come when flying in eastern Europe and the Baltics, bordering Russia.
While potentially dangerous, modern aircraft have other alternative systems for navigation.
“In recent years there has been a rise in intermittent GPS interference which has affected all airlines,” Ryanair said.
“Our aircraft have multiple systems to identify aircraft location, including GPS and if any are not functioning, can switch to one of the alternate systems.”
As well as Ryanair, it impacted 1,368 Wizz Air flights, 82 British Airways flights and four easyJet flights.
Glenn Bradley, head of flight operations at the CAA, said: “Aviation is one of the safest forms of air travel and there are several safety protocols in place to protect navigation systems.”
“GPS jamming does not directly impact the navigation of an aircraft, and a known issue does not mean an aircraft has been jammed deliberately.”
