Pakistan, Nov. 15 -- The US Federal Aviation Administration (FAA) lifted a nationwide ground stop on Friday after a communications failure at air traffic control centres disrupted flight operations across the country, triggering widespread airport chaos and the longest nationwide shutdown since the September 11, 2001 attacks.

The ground stop, imposed at 3:54pm Eastern Time, remained in effect for more than four hours. Airlines cancelled more than 4,700 flights and delayed 10,000 others on Friday, while another 700 cancellations had already been recorded for Saturday, according to flight-tracking service FlightRadar24. Aviation analysts warned that it could take days for airlines to restore their schedules.

The disruption also spread bey...