A copper wire upgrade was the root cause of a nationwide US ground stop that triggered widespread travel chaos and thousands of flight cancellations, according to US Transport Secretary Sean Duffy. Speaking at a news conference, Duffy explained that the government is actively investigating whether the disruption stemmed from human incompetence by the contractor performing the work or from faulty equipment.
The incident marked the longest suspension of its kind since the September 11, 2001, terrorist attacks. The airspace shutdown forced no flights to take off from the continental United States for more than four hours starting at 15:54 EST on Friday. According to flight tracking website Flight Aware, the aftermath resulted in more than 3,500 flight cancellations and over 2,000 delays by Saturday, with knock-on effects expected to persist for days as airlines struggle to recover.
Investigating the Copper Wire Upgrade Failure
Maintenance work was being carried out to transition legacy infrastructure from copper wire to fibre optics by technology provider contractor L3Harris, Duffy noted. Highlighting the fragility of national aviation infrastructure, Duffy remarked that the United States possesses “an incredibly old telecommunications system,” adding that the specific wire being replaced was so outdated that manufacturers were discontinuing it.
The technical failure occurred when a router undergoing maintenance began flooding other air traffic control systems. This overflow generated severe communication issues with aircraft, prompting the government to order a total airspace shutdown for safety reasons. Federal Aviation Administration (FAA) head Bryan Bedford confirmed during the same press briefing that authorities see “zero evidence of anything nefarious, and zero evidence of anything AI related.” Duffy reiterated that investigators currently found no indication that the incident resulted from a cyber-attack, though a full investigation remains ongoing.
Infrastructure Challenges and Future Risks
The sudden suspension left many travellers stranded, with some passengers trapped inside aircraft on airport tarmacs, unable to take off or return to terminal gates. Although certain international flights eventually received clearance to depart in an effort to free up airport space, the disruption severely impacted schedules nationwide.
Following the crisis, Duffy warned that similar operational failures could happen again unless the US Congress approves substantial funding for air traffic control modernization. US President Donald Trump has formally requested $30.1 billion for infrastructure upgrades. Former TSA Administrator John Pistole told the BBC that while the ability to restart the system within four and a half hours demonstrated resilience, it raised critical questions about the long-term reliability of America’s aviation networks. Both chambers of Congress are currently controlled by the Republican Party as lawmakers face mounting pressure to fund necessary system overhauls, as reported by the BBC.
Source: Copper wire upgrade caused nationwide flight suspension, US transport secretary says (source-feed timestamp 2026-11-14T17:16:36+00:00). AI-assisted report based on the cited linked article and its RSS feed; details were not independently verified.
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