Domestic flight departures in the country are gradually returning to normal after the computer failure that triggered a cascade of delays at all airports.

The Federal Aviation Administration (FAA) reported on January 11, 2023, that all domestic US departures had been canceled owing to a problem with the US flight control systems (NOTAMS). Commercial airline pilots use NOTAMS for real-time information on flight hazards and restrictions. The FAA stipulates NOTAMS are not to be relied on as a sole source of information, and so some flights may be able to satisfy safety requirements by using other data.

FAA ordered a nationwide ground stop due to a computer glitch that required a 90-minute pause to all U.S. departing aircraft. But airlines continued to delay or cancel flights because of ongoing congestion.
More than 10,000 flights have been delayed or canceled thus far, marking the first nationwide suspension of flights in about 20 years. Many business leaders linked the grounding to the events that followed the September 11, 2001 terrorist attacks.

Although airline officials expressed confidence that normal operations could return in large part by Thursday, major carriers including Southwest Airlines Co (LUV.N), United Airlines (AAL.O), Delta Air Lines (DAL.N), and American Airlines (AAL.O) all reported Wednesday that 40% or more of flights were delayed or canceled.

Major US carriers including United Airlines, Delta and American Airlines all said they had grounded flights in response to the situation. United and Delta have issued travel waivers in response to the outage. American Airlines said its customers could rebook their flights Wednesday and Thursday without additional fees.

Follow the FAA and relevant airports’ and airlines’ updates. Before heading to the airport, confirm your flight. Give yourself extra time to check in and get through airport security.