Finnair is preparing to restore services to the Estonian city of Tartu, following a reinforcement of ground navigation equipment that will serve as an alternative to GPS.
The carrier had suspended the route from Helsinki on 29 April after incidents in which ATRs – operated by its regional partner carrier Norra – encountered GPS interference.
Finnair states that it will resume Tartu flights on 2 June.
Vice-president of operations control says the Estonian air navigation service EANS has “done an excellent job” by implementing an alternative system, which is based on distance-measuring DMEs.
EANS chief Ivar Vark says the organisation has received confirmation that the DME signals provide “sufficient coverage” in lower airspace.
“This means that we have found a solution that enables us…to continue serving these flights for which GPS or another conventional navigation solution is a necessary prerequisite,” he adds.
“During validation we found that the signal sent from the DMEs works very well at an altitude range where the additional coverage was needed.
“Flights can [travel], in Tartu’s case, from controlled airspace to the [ILS]. Now we need to add this solution to the procedures and then the pilots can start using it.”
Finnair will operate twice-daily to Tartu, six days per week.
EANS says DME has served as an alternative for higher-altitude traffic, above 10,000ft, since March. It adds that no other flights, besides Finnair’s, have turned back or been cancelled as a result of the GPS disturbances.
