Thousands of flight delays and cancellations rippled across the US early Wednesday after a computer outage led to a grounding order for all departing aircraft by the Federal Aviation Administration (FAA). The aviation agency lifted the order shortly before 9am Eastern Time and said normal operations were resuming across the country.
According to the flight tracking website FlightAware, nearly 5,000 flights within, into or out of the US had been delayed on Wednesday at around 10am ET. Approximately 900 had been canceled.
Update 5: Normal air traffic operations are resuming gradually across the U.S. following an overnight outage to the Notice to Air Missions system that provides safety info to flight crews. The ground stop has been lifted.
We continue to look into the cause of the initial problem
— The FAA ✈️ (@FAANews) January 11, 2023
While the White House initially said that there is no evidence of a cyberattack, President Joe Biden said “we don’t know” and told reporters that he’s directed the Department of Transportation to investigate the cause of the disruption.
The stop order was lifted just before 9 am ET, but delays and cancellations were still expected to snowball. Departure gates at major airports were filled with aircraft that had been ordered grounded for hours. More than 21,000 flights were scheduled to take off in the US on Wednesday, mostly domestic trips, and about 1,840 international flights expected to fly to the US, according to aviation data firm Cirium.
The system failure affected what is known as the Notice to Air Missions System (NOTAMs). Before commencing a flight, pilots are required to consult NOTAMs, which list potential adverse impacts on flights, from runway construction to the potential for icing. The system used to be telephone-based, with pilots calling dedicated flight service stations for the information, but has now moved online.
According to FAA advisories, the NOTAM system failed at 8.28 pm ET on Tuesday, preventing new or amended notices from being distributed to pilots. The FAA resorted to a telephone hotline in an effort to keep departures flying overnight, but as daytime traffic picked up it overwhelmed the telephone backup system.
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