Mysterious GPS Disruptions Spread Across Texas; FAA Issues Warning to Pilots

The Dallas-Fort Worth International Airport as seen in a file photo. (Screenshot via Google Maps)

The Federal Aviation Administration this week warned pilots about mysterious disruptions to GPS signals in Texas as a runway at the Dallas-Fort Worth International Airport was shut down.

The FAA told Bloomberg that it’s investigating possible jamming of the global positioning system (GPS) that aircraft use to guide them to runways and during their flights. The FAA also confirmed that the Dallas airport runway was shut down temporarily.

So far, according to the FAA, it has found “no evidence of intentional interference.” However, the agency didn’t appear to say what might be the cause. The FAA didn’t respond by press time to a request for comment.

American Airlines told Bloomberg that the GPS problem wasn’t affecting its business, and Southwest Airlines said it wasn’t experiencing any disruptions.

Flight tracking website ADS-B appeared to have been the first to report GPS interference around Dallas on Oct. 17.

“Significant GPS interference being reported by pilots in the Dallas area. Aircraft being rerouted onto non-RNAV arrivals,” it wrote.

As of Oct. 18, according to ADS-B’s website, GPS interference was being reported also near Waco, Texas, and near the Fort Hood military base in Killeen.

Dan Streufert, founder of the flight-tracking website, told Bloomberg that such interference in the Dallas area is unusual.

“In the U.S., it’s very unusual to see this without a prior notice,” Streufert noted.

“GPS jamming has always been a risk area,” R. John Hansman, an aerospace professor at the Massachusetts Institute of Technology, told the outlet. “It’s not that difficult or expensive technically to jam GPS. Which is why we don’t use GPS as the only navigation source.”

In January, officials in Denver issued an alert that GPS was unreliable within a 50-mile radius of the Denver International Airport due to interference. It isn’t clear what caused the interference.

A spokesperson for the U.S. Department of Homeland Security, Mike Roskind, told GPSWorld last month that the Denver incident lasted about 33 hours and impacted various infrastructures and systems across the area. Radio systems with no backups were negatively impacted, he said, although wireless and cellular service providers that had backups performed fine. Roskind said a report on that incident will come in October.

Top federal officials have warned that GPS is considered a vulnerability within the U.S. national security apparatus.

Caitlin Durkovich, National Security Council director for response, said in December 2021 that the system is “still a significant single point of failure in our country” because “positioning, navigation, and timing is foundational to our life.”