Chaos in the sky.
Thousands of flights were canceled or delayed in the United States on Wednesday due to a computer failure that forced the American civil aviation regulator (FAA) to temporarily suspend all domestic flight departures, the White House ruling out stage the possibility of a cyberattack.
The incident, which began overnight from Tuesday to Wednesday, affected a crucial information system for pilots and crews.
To ensure air traffic safety, the FAA has decided to prevent all takeoffs of domestic flights until 9:00 a.m. on the east coast of the country (3:00 p.m. Paris time), with a few exceptions, the time to resolve the problem.
According to the FAA's latest tweet, "normal air traffic operations are gradually resuming" across the country.
More than 1,100 flights were canceled and more than 7,300 were delayed, according to a count from the specialized site Flight Aware around 5:30 p.m. GMT.
At Ronald Reagan airport, located near Washington, the departure boards were riddled with red flags indicating delays.
At Mexico City airport, several flights to the United States were also delayed, noted an AFP journalist.
Attention is now focused on the cause of the failure, which has not yet been identified by the FAA.
Asked about the subject before the take-off ban was lifted, US President Joe Biden said he spoke with his Minister of Transport, Pete Buttigieg, but did not know the origin of the breakdown at the time.
Regulators “expect to have a better idea in a few hours and will react at that time,” he said.
White House spokeswoman Karine Jean-Pierre said on Twitter that there was at this stage “no sign that this was a cyberattack”.
Pete Buttigieg called for an investigation "to determine the causes (of the outage) and recommend next steps."
The chair of the US Senate Committee on Transportation, Maria Cantwell, also warned that a committee would examine the causes of the disruptions.
"The public needs a resilient air transport system," said the elected Democrat in a press release.
Air traffic in the United States had already been badly shaken at Christmas time by an extreme cold spell accompanied by snowfall, which had caused cascading cancellations for several days within the Southwest company.
Several Republicans have also strongly criticized the FAA, like Senator Ted Cruz who, in a press release, deemed the agency's inability to operate an important safety system "unacceptable".
The Notice To Air Missions (NOTAM) system, affected by Wednesday's outage, makes it possible to transmit information to flight crews concerning risks in airports, such as work on a landing strip, for example.
A total of 21,464 flights are expected to take off from the United States on Wednesday, the vast majority being domestic routes, according to figures from specialist firm Juliett Alpha.
Around 2 million passengers could potentially be affected by the incident.