US air traffic is delayed nationwide due to an outage in the communication system of the Federal Aviation Authority (FAA). The regulator ordered all US airports to reschedule departures on Wednesday morning.

The problem has since been resolved. The FAA announced that aeroplanes were cleared to depart from airports in a statement on Twitter around 3 p.m. (Amsterdam time).

Earlier today, the regulator announced an outage in a key communications system called Notice to Air Missions. The FAA uses the system to notify pilots in US airspace of closed runways, equipment failures and other potential hazards.

The regulator confirmed that the system suffered an outage on the night of January 10-11. US airports were ordered to reschedule all departures on Wednesday morning, including flights from European airlines such as Air France-KLM.

The FAA said that air traffic in the United States was slowly recovering in an update posted at around 3 p.m. (Amsterdam time). The cause of the problem has not been disclosed at the time of writing. The FAA said the investigation is ongoing.

Dark day

According to tracking website FlightAware, more than 4,000 flights have been delayed, and more than 700 have been cancelled entirely. A video from news channel CNN depicts travellers at a Pennsylvania airport being informed that all departures have been rescheduled. “This is a nationwide problem”, a spokesperson says over the intercom.

CNN spoke to a family who said they were trapped at an airport in Hawaii for more than five hours. The family intended to travel to Dallas, but were informed that the plane would not be departing just before the flight. A passenger in London told the news channel that his plane was grounded for three additional hours before departure.

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