Denver Air Traffic Controllers Lose Contact With Planes During 90-Second Communications Outage

Both the primary and main backup frequencies went down, forcing controllers to use an emergency frequency to relay instructions to pilots.

A United Airlines jetliner prepares to push off from a gate at Denver International Airport on May 7, 2025. David Zalubowski/AP Photo

Air traffic controllers in Denver were forced to quickly switch to emergency backup frequencies after losing contact with planes for roughly 90 seconds earlier this week, according to the Federal Aviation Administration (FAA).

This marks the latest in a series of equipment failures that have raised concerns about the nation’s aging air traffic control system.