US flights are resuming after a nationwide order grounded all outbound aircraft, but thousands of passengers remain stranded following an outage blamed by officials on ageing technology.
The failure led to the cancellation of 12,000 flights across the country. Services are now restarting as airlines work to clear the disruption.
US officials have attributed the outage to out-of-date technology, without further details being provided. The impact of the breakdown continues to be felt by passengers as air travel returns to operation.
