Colorado, May 16 - The Denver Air Route Traffic Control Center in Longmont, on Monday, May 12, 2025, experienced a communications outage that disrupted contact between air traffic controllers and pilots for approximately 90 seconds, though some reports suggest the disruption may have lasted up to six minutes. This incident, affecting one of the busiest aviation hubs in the United States, has raised concerns about the reliability of the nation’s aging air traffic control infrastructure, particularly in light of similar recent failures at Newark Liberty International Airport. The Federal Aviation Administration (FAA) confirmed that the outage impacted both primary and backup radio frequencies, forcing controllers to switch to an emergency frequency to restore communication with aircraft. Despite the disruption, radar operations remained unaffected, and the FAA reported that all aircraft maintained safe separation, with no operational impacts or incidents resulting from the event.
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The Denver Air Route Traffic Control Center oversees approximately 285,000 square miles of airspace, covering Colorado and parts of eight neighboring states, including Arizona, New Mexico, and Utah. Around 1:50 p.m. local time, both transmitters covering a segment of this airspace failed, affecting communication with an estimated 15 to 20 aircraft approaching Denver International Airport (DIA). Controllers quickly utilized a 121.5 MHz emergency frequency, typically reserved for distress situations, to relay instructions to pilots and direct them to a secondary frequency. This swift response mitigated potential risks, but the incident has spotlighted ongoing challenges within the FAA’s air traffic control system. According to sources, four frequencies from the center’s two main towers were already out of service prior to the outage, leaving controllers reliant on a backup channel that subsequently failed.
This event follows a series of high-profile disruptions at Newark Liberty International Airport, where radar and radio outages over the past few weeks have caused significant delays and cancellations. The FAA has attributed these incidents to outdated equipment and staffing shortages, issues that have plagued the agency for decades. A 2024 Government Accountability Office report highlighted that 51 of the FAA’s 138 air traffic control information systems are unsustainable due to obsolete technology and a lack of spare parts. In response, the U.S. Transportation Department (USDOT) has proposed a multibillion-dollar overhaul of the national air traffic control system, which includes replacing 618 radars, installing 4,600 high-speed network connections, and upgrading controllers’ computers. The exact cost remains undetermined, but aviation industry estimates suggest a price tag of at least $30 billion.
The Denver outage, while brief, underscores the urgency of modernizing the FAA’s infrastructure. As air travel demand surges post-pandemic, incidents like those in Denver and Newark highlight the vulnerabilities of a system strained by aging technology and understaffing. The FAA is currently investigating the cause of the Denver incident, which remains unknown, and has emphasized that safety was not compromised. However, with similar disruptions occurring nationwide, pressure is mounting for comprehensive reforms to ensure the reliability and safety of U.S. airspace.