Flight disruption at Heathrow linked to Friday's unprecedented US air traffic shutdown was easing by Saturday afternoon, with the knock-on effect on departures to America now limited mostly to delays rather than cancellations, though the UK's aviation regulator is still warning passengers to expect some further disruption.
The US Federal Aviation Administration (FAA) ordered a nationwide ground stop on Friday, halting all domestic departures across the continental United States for more than four hours, from 15:54 to 20:15 US Eastern time (19:54 to 00:15 GMT), after a telecommunications and radar problem hit air traffic control systems. US officials said outdated equipment being overwhelmed by newer technology was to blame, and said there was no evidence of a cyber-attack. Almost 10,000 flights were cancelled across the US, according to tracking site Flightradar24, with more than 15,000 delayed or cancelled in total and an estimated 1.5 million passengers affected, making it the most disruptive US ground stop since the September 11 attacks in 2001.
US airspace reopened on Friday evening, with Transportation Secretary Sean Duffy confirming shortly after 1.30am GMT on Saturday that flights were resuming, but warning the ripple effects would last for days as airlines cleared a backlog.
At Heathrow, cancellations on US routes climbed through Saturday morning, rising from 29 to 31 scheduled departures by 9.45am, with around 20 more delayed, largely on British Airways, American Airlines, United Airlines and Delta services to cities including New York, Chicago, Dallas and Los Angeles.
By Saturday afternoon, The Independent reported that the knock-on effect at UK airports had eased to delays on a smaller number of US carrier flights, with only a handful of departures, including American Airlines services to Charlotte, Dallas and Los Angeles, still showing as cancelled on Heathrow's boards.
The UK Civil Aviation Authority (CAA) confirmed in an official statement on Saturday that "while US flights have resumed, there may be some follow-on disruption as airlines work to re-book affected passengers and get all services back to normal." Tim Johnson, the CAA's consumer director, said anyone travelling between the UK and the US "should check with their airline for the latest information before heading to the airport," adding that UK airlines were "doing all they can to minimise inconvenience."
Gatwick was also affected, with three arrivals from Orlando cancelled earlier on Saturday, though the wider impact there was described as minimal.
What this means for your journey: if you are flying to or from the US via Heathrow over the next few days, check your flight status with your airline before leaving home, since some delays and rebooking knock-on effects are still expected even though the ground stop itself has been lifted. If you are driving in to collect or drop off a delayed passenger, see our /parking/ guide for current charges and short-stay options.