Flights from British airports have resumed early on Wednesday (local time) after a major air traffic control failure, but hubs warned that it would take time for operations to return to normal and questions mounted about the reliability of Britain's aviation systems.

More than 1,000 departures and arrivals into British airports were cancelled today, with thousands of passengers left stranded.

A technical problem with Britain’s air traffic control system disrupted flights across the country on Tuesday, with more than 1,000 flights canceled, according to flight tracking…