Could overloaded FAA routers ground US Thanksgiving flights after Friday’s nationwide shutdown? A five-hour FAA ground stop exposed weaknesses in America's ageing air traffic control network. Overloaded routers and a telecommunications outage disrupted thousands of flights, causing more than 10,000 delays and 4,000 cancellations. Flights resumed after system checks, but the incident raises questions about whether the FAA can prevent another shutdown during Thanksgiving's busy travel period.
Thanksgiving could bring nearly 29 million passengers onto US airline networks between November 20 and 30. The holiday rush will put airports and air traffic controllers under heavy pressure. The concern comes just days after the Federal Aviation Administration (FAA) grounded departing flights nationwide because overloaded routers disrupted air traffic communications.
The airspace has reopened, but officials have not ruled out further technical failures. Could the same problem return when millions of Americans are travelling for Thanksgiving on November 26?
The numbers show why Friday's outage has raised concern. Airlines expect to carry around 2.7 million passengers every day during the 11-day Thanksgiving travel period. They are adding an average of 38,000 seats daily compared with last year. November 29 and 30 are expected to be the busiest days. These figures come from Airlines for America, which published its forecast on November 10.
American Airlines expects more than 8 million customers between November 19 and December 1. The airline and its regional partners have scheduled nearly 85,000 flights, 4% more than last Thanksgiving.
November 29 will be particularly busy. American has scheduled 7,021 flights that day, its largest operating day since the pandemic. At certain points, the airline expects to have 1,130 aircraft flying at the same time.
United Airlines also expects more than 500,000 passengers daily during the holiday period. Its passenger numbers could reach around 600,000 on November 29.
These are the schedules airlines are preparing to operate. Friday's shutdown has raised a separate concern about the system needed to manage all those flights.
A nationwide communications failure during the Thanksgiving rush could affect thousands of scheduled departures. Even a shorter interruption could leave aircraft and crews out of position. Passengers could face cancellations and delays long after the original problem is fixed.
The FAA lifted its nationwide ground stop at 8:15 p.m. Eastern time on November 13. Transportation Secretary Sean Duffy announced the reopening after around five hours of disruption.
The shutdown affected departing flights across the United States. Aircraft already in the air were allowed to continue and land safely. Airlines then faced the task of restoring their schedules.
Friday's reopening did not clear the backlog. The Associated Press reported more than 2,500 cancellations and hundreds of delays across US airports on Saturday. International flights were also affected. European aviation authorities temporarily suspended US-bound departures at the FAA's request.
Duffy blamed ageing equipment in the country's air traffic control network. He said its routers became overloaded with data and began sending inconsistent information.
Routers pass information between computers and networks. Air traffic controllers depend on reliable communications and radar information to manage aircraft. The FAA could not take the risk of continuing departures with the system behaving unpredictably.
There are questions about what triggered the failure. Sources told CBS News that an update to the private communications network operated by L3Harris caused the system to reboot. Mullin said security patches added to the older equipment appeared to overwhelm its routers.
Both accounts point to problems involving new updates and ageing infrastructure. Officials have not provided a complete explanation of the failure.
Mullin also said there was no indication of a cyberattack. He rejected a connection with the Microsoft outage reported around the same time.
Duffy expects the air traffic control system to be operating normally by Thanksgiving. The FAA says it tested the system before allowing flights to resume.
But the larger problem remains. The equipment that failed has not been completely replaced.
The government has secured $12.5 billion for air traffic control modernisation. Duffy has called for another $30 billion to complete the work. The Associated Press reported that the administration is seeking the additional funding.
There is no official warning of another nationwide ground stop on November 26. There is also no guarantee that the same technical failure cannot happen again.
The pressure will increase as November 20 approaches. Nearly 29 million passengers are expected to fly during the holiday period. Airlines are running thousands of additional flights, with the busiest travel days still to come.
