US Flights Resume After Nationwide Grounding Lasting Over Four Hours

The United States went over four hours without any flight departures this Friday (13). The FAA, the agency that regulates American civil aviation, ordered a halt to all airport departures at 3:54 PM New York time, 5:54 PM in Brasilia, following a telecommunications outage at centers controlling en-route flights.

The airspace reopened at 8:15 PM New York time, 10:15 PM in Brasilia, according to Transportation Secretary Sean Duffy. Aircraft already in the air continued their journeys. Domestic flights in Alaska and Hawaii were not affected.

When the order was issued, more than 3,500 planes were in the air, Duffy said. About 11,000 flights, carrying over 1.5 million passengers, were scheduled to depart after 4:00 PM New York time. By the end of the night, cancellations surpassed 4,000 and delays exceeded 10,000, according to flight tracking websites. Hundreds of planes were diverted to other airports.

Duffy attributed the outage to outdated equipment. According to him, routers and switches in a still-analog telecommunications network became overloaded with data and began sending inconsistent information to controllers. The FAA called the incident a temporary telecommunications failure and stated that it grounded flights as a precaution.

Secretary of Homeland Security Markwayne Mullin stated that there is currently no evidence of an attack and that the failure is unrelated to the Microsoft service outage on Thursday (12). The exact cause remains under investigation.

Airlines scrambled to rebook passengers. JetBlue canceled the remainder of its Friday schedule, with the exception of departures to Europe. Air Canada and Porter canceled flights to and from the United States. Delta and United waived rebooking fees. Duffy warned that the return to normal operations will be slow and cancellations are expected to extend through the weekend.

This was the first nationwide flight grounding in the country since January 2023, when a failure in the pilot notification system held departures for about 90 minutes. This time, the interruption lasted more than four hours.

Shares of American, United, and Delta fell in after-hours trading. Duffy used the episode to demand $50 billion from Congress to modernize air traffic control, and senators have requested explanations from the FAA.