Pilots flying into Denver International Airport (DEN) were cut off from communicating with air traffic controllers for 90 seconds during the latest US outage, according to the Federal Aviation Administration (FAA).
On May 15, 2025, Frank McIntosh, Deputy CCO of Air Traffic Organization at the FAA, revealed details about the communication breakdown when he appeared in front of the Committee on Transportation and Infrastructure.
McIntosh told lawmakers that on May 12, 2025, one of the frequencies used between pilots and air traffic control was lost, requiring them to switch to a backup frequency to regain communication.
“The aircraft at the time of that frequency outage were all separated by air traffic procedures and separation standards. There was no loss of separation,” explained McIntosh.
Reports by some media organizations that the outage lasted for six minutes were dismissed by McIntosh as being “over-exaggerated”.
According to Fox News, 20 pilots were left without means to communicate with air traffic control.
In response to hearing the committee evidence, Rep. Robert Garcia of California said it was an “absolutely shocking system failure,” requiring “immediate solutions”.
Following McIntosh’s evidence, the FAA released a statement confirming that “part of” the Denver Air Route Traffic Control Center (ARTCC) “experienced a loss of communication for approximately 90 seconds at 1:50pm, local time […] when both transmitters that cover a segment of airspace went down”.
The FAA added: “Controllers used another frequency to relay instructions to pilots. Aircraft remained safely separated and there were no impacts to operations. The FAA is investigating.”
The incident in Denver follows heightened concerns surrounding ageing air traffic control systems in the US and a spate of outages at Newark Liberty International Airport (EWR).
On May 11, 2025, a third radar outage at the Philadelphia Terminal Radar Approach Control (TRACON) in the space of two weeks caused flight disruptions.
