A rare nationwide ground stop in the United States has delayed or cancelled thousands of flights, with officials warning that the disruption could continue until Sunday night as airlines work through the backlog.
The Federal Aviation Administration halted departures from airports across the country on Friday after communication problems affected several air route traffic control centres. The order was lifted at about 8.15pm Eastern Time, but passengers continued to face cancellations, delays and crowded airports over the weekend.
US Transportation Secretary Sean Duffy said more than 3,500 aircraft were in the air when the disruption began. Controllers and pilots brought the planes down safely while the FAA investigated instability affecting communications with aircraft and some radar feeds.
The airspace was reopened after the agency restored full functionality to its air traffic control centres and terminal radar approach control facilities. More than 8,000 flight operations resumed on Friday night, officials said, although airlines were left to reposition aircraft and crews before normal schedules could return.
US flight disruption expected to continue
FAA administrator Bryan Bedford said travellers should expect further delays and cancellations before the system recovered. He said airlines believed they could restore their full schedules by the close of business on Sunday.
Mr Duffy said the problem appeared to be linked to ageing telecommunications equipment rather than a cyber attack. A contractor had been carrying out routine work to replace old copper connections with fibre at a remote FAA site, and officials were investigating whether a faulty router or an installation error caused other equipment to become overwhelmed.
The secretary said the affected system generated more than 1,000 connection attempts every four to five seconds, creating inconsistencies in communications and radar data. The FAA ordered the ground stop as a safety precaution, rather than allowing flights to operate with unreliable information.
Airlines have advised passengers to check directly with their carrier before travelling, as the consequences of the four-hour stoppage are expected to ripple through schedules until the recovery is complete.
