Airlines in the United States resumed departures and a ground stop was lifted on Wednesday after a system outage the previous night had forced a halt to all departing flights. Computer outage forces massive flight disruption in US.
As the Federal Aviation Administration (FAA) scrambled to fix the cause of the problem, over 4,300 flights were delayed and 700 cancelled.
The FAA had ordered airlines to pause all domestic departures after its pilot alerting system crashed and the agency had to perform a hard reset two hours after midnight, officials said.
They said the cause for the massive disruption was unclear, adding they had found no evidence of a cyber attack.
“Normal air traffic operations are resuming gradually across the US following an overnight outage to the Notice to Air Missions (NOTAM) 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 said in a tweet.
A NOTAM is a notice containing information essential to personnel concerned with flight operations, but not known far enough in advance to be publicised by other means.
Information can go up to 200 pages for long-haul international flights and may include items such as runway closures, bird hazard warnings and construction obstacles.
The FAA is expected to implement a ground delay programme in order to address the backlog of flights halted for hours. Flights already in the air had been allowed to continue to their destinations during the ground stop.
US President Joe Biden ordered the Transportation Department to investigate the outage and said the cause of the failure was unknown at this time. Asked if a cyber attack was behind the outage, Biden told reporters at the White House: “We don’’ know.”
Transportation Secretary Pete Buttigieg pledged “an after-action process to determine root causes and recommend next steps”.
The FAA said it was working to restore the NOTAM system, which alerts pilots to hazards and changes to airport facilities and procedures that had stopped processing updated information.
