US flight shutdown exposes deepening air traffic network crisis

CHICAGO: A communications failure that halted flight departures across the United States on Friday (Nov 13) has renewed scrutiny of the country's ageing air traffic control network, raising questions about its resilience even as the government spends billions of dollars to modernise it.

The Federal Aviation Administration (FAA) ordered a nationwide ground stop, preventing aircraft from departing US airports, following "a communication issue impacting all Air Route Traffic Control Centers", Transportation Secretary Sean Duffy said in a post on X.

Duffy later attributed the outage to a problem with the FAA's legacy network, saying switches and routers had become overloaded with data and went down. It was not immediately clear what caused the equipment overload.

The FAA lifted the ground stop after more than four hours, but Duffy warned that it would take time for air traffic operations to return to full capacity.

More than 1.5 million passengers were scheduled to depart US airports on roughly 11,000 flights after 4pm Eastern Time (2100 GMT), shortly after the ground stop began, according to aviation analytics firm Cirium.

The shutdown came on the same day the White House and Transportation Department sought another US$30.1 billion from Congress to upgrade airports and air traffic control, including US$10.1 billion for air traffic control modernisation.

Much of the system's underlying weakness has been documented for years.

The Government Accountability Office reported in 2024 that the FAA had classified 51 of its 138 air traffic control systems as unsustainable and another 54 as potentially unsustainable. Together, they accounted for more than three-quarters of the systems reviewed.

FAA Administrator Bryan Bedford told Reuters in September that the agency's more than 300 air traffic facilities operated as technological silos, relying in some cases on decades-old computers and telecommunications systems that cannot communicate seamlessly with one another.

Some obsolete equipment requires replacement parts obtained through online auction websites or made using 3D printing.

BACKUP SYSTEMS UNDER STRAIN

An incident in September demonstrated how one communications failure could be compounded by another.

After error messages appeared on a telecommunications circuit serving a Philadelphia air traffic control facility, the FAA's contractor switched to a backup fibre-optic line. A construction crew then accidentally severed that line in New Jersey, contributing to widespread disruption. About 9,500 US flights were delayed or cancelled that day.

"When it fails, we just don't have the redundancy that we would get if we had a modern architecture," Bedford said at the time.

Friday's shutdown was the first nationwide ground stop since January 2023, when a failure of the FAA system that distributes critical safety notices to pilots halted departures for less than two hours and disrupted more than 10,000 flights.

Congress approved US$12.5 billion in July 2025 to modernise the country's ageing air traffic control infrastructure, including telecommunications and radar systems. The administration said Friday that 68 per cent of the FAA's legacy copper telecommunications network had been replaced with high-speed fibre.

But Bedford warned in September that replacing ageing copper wires with fibre-optic cables alone would not prevent future outages without a modern telecommunications network.

The overhaul faces challenges beyond securing money.

In September, the Government Accountability Office warned that the FAA lacked a reliable cost estimate and an integrated master schedule for its air traffic control modernisation programme.

Instead, as of May, it had 11,389 separate project schedules that were not coordinated, raising the risk of repeated work at the same facilities, delays and cost overruns.

The FAA aims to complete the first phase of modernisation by December 2028. But the GAO warned that inadequate planning increased the risk of delays, potentially leaving the agency dependent on outdated systems prone to failure for longer.