US air traffic vulnerabilities exposed by old computers, severed cables and stalled upgrades

By David Shepardson

WASHINGTON, Sept 23 (Reuters) – America’s aging air traffic control system — reliant on outdated telecom systems, decades-old Compaq computers and replacement parts bought on eBay — keeps failing.

In the latest example, thousands of flights across the densely populated Northeast were delayed or canceled on Monday due to the dual failures of a circuit at a Philadelphia air traffic facility and the accidental cut of a fiber-optic cable near New Brunswick, New Jersey, by a construction crew.

“The architecture of our telecom is still a 40-year-old architecture, which means you could have a switch go down and a line be cut yesterday and the Northeast goes down,” U.S. Transportation Secretary Sean Duffy said on Tuesday.

The disruption underscores how fragile the nation’s air traffic control network has become after decades of delayed modernization efforts, underfunding and piecemeal fixes.

Despite billions already spent or approved, the Federal Aviation Administration still relies on aging, often incompatible systems that can turn a single equipment failure or severed cable into flight chaos — a risk officials warn will persist without a far larger overhaul.

In January 2023, all flights departing the U.S. were grounded for the first time since the September 11, 2001, attacks after a contractor accidentally deleted computer files, affecting a key pilot messaging database. The outage disrupted 11,000 flights before the issue was solved.

In September 2025, more than 2,000 flights were delayed and hundreds were canceled at two Dallas-area airports due to a telecom outage after a contractor cut fiber lines, impacting communication systems at the Dallas airports. It disrupted flights for 100,000 American Airlines passengers alone.

There have been repeated serious technology issues, which last year convinced Congress to approve $12.5 billion to modernize air traffic control systems. Duffy said on Tuesday he wants another $30 billion to complete upgrades and fix facilities.

“These incidents will continue to happen unless we get the resources and actually build the architecture fit for the 21st century,” Duffy said.

Across the Atlantic, Britain has also suffered major air traffic control outages this month that have led airlines to question the resilience of its systems.

AGING TECHNOLOGY

The FAA has been forced to use 3D printing or to go to eBay for replacement parts for some of its aging systems. In other cases, the FAA can no longer get spare parts.

The Government Accountability Office in 2024 said the FAA needed to take “urgent action” to address aging air traffic control systems, noting that one-third are unsustainable.

The FAA’s more than 300 air traffic facilities cannot talk to one another and operate on individual analog computers. “Every facility is a silo,” FAA Administrator Bryan Bedford told Reuters in a recent interview. “We’re behind 20 years.”

He said effectively the FAA’s towers are run on individual Compaq computers. The brand, which was acquired by HP, stopped producing computers in 2013.

The FAA still has aging telephone systems and three telecom systems that are not interoperable and have a “clunky connection” that often forces delays, Bedford said.

At the same time, the US has the world’s most complex airspace and faces a shortage of several thousand air traffic controllers.

One big step is expected in late 2027 when air traffic control will move from analog to digital communications. The FAA will ​later shift all of the facilities from running on individual computers to the cloud.   

The FAA has tried for decades to modernize the system, but those efforts have repeatedly fallen short.

In 1982, the FAA first released a comprehensive plan for improving air traffic control services, estimating it would cost about $10 billion by the late 1990s. 

The Government Accountability Office in 1995 said the cost had ballooned to at least $36 billion on the effort to consolidate facilities and standardize computer hardware and software.

Another FAA reform effort dubbed “NextGen” launched in 2004 was pegged at $15 billion, but a report last year said it has faced numerous delays and cost overruns and is less ambitious than what was envisioned more than 20 years ago.

“FAA has delivered a delayed, over budget, and less transformational NextGen than originally planned,” said the Transportation Department Office of Inspector General.

The FAA has also been working for years to end a long-ridiculed, decades-old practice of air traffic controllers using paper flight strips to keep track of aircraft. But adopting the change, which started in 2022, at 49 major airports will take the FAA until at least 2028. The FAA said 18 major airports have already gotten rid of the paper strips.

(Reporting by David Shepardson; Editing by Jamie Freed)