The Federal Aviation Administration is investigating the cause of mysterious GPS interference that, over the past few days, has closed one runway at the Dallas-Fort Worth International Airport and prompted some aircraft in the region to be rerouted to areas where signals were working properly.
The interference first came to light on Monday afternoon when the FAA issued an advisory over ATIS (Automatic Terminal Information Service). It warned flight personnel and air traffic controllers that GPS interference over a 40-mile swath of airspace near the Dallas-Fort Worth airport. The advisory read in part: “ATTN ALL AIRCRAFT. GPS REPORTED UNRELIABLE WITHIN 40 NM OF DFW.”
A dramatic impact
An advisory issued around the same time by the Air Traffic Control System Command Center, meanwhile, reported the region was “experiencing GPS anomalies that are dramatically impacting” flights in and out of Dallas-Fort Worth and neighboring airports. It went on to say that some of the airports were relying on the use of navigation systems that predated GPS.