Thousands of flights were cancelled across the United States on Friday, after a huge computer and communication problem forced air traffic controllers to stop all planes from taking off for more than four hours.
It was the longest nationwide “ground stop” in 25 years, and only the second time this has happened since the attacks of 11 September 2001.
Officials said the problem happened while a contractor was replacing old copper wires in the air traffic control system with modern fibre-optic cables, as part of a major upgrade. Somehow, the new technology overloaded the old equipment, causing radar and communication gaps.
More than 10,000 flights were affected, with over 4,100 cancelled completely, according to flight-tracking website FlightAware. Luckily, officials said more than 3,000 planes already in the air at the time landed safely, and nobody was in danger.
US Transportation Secretary Sean Duffy admitted the contractor had let them down. “Our contractor didn’t meet the moment,” he said.
The head of the Federal Aviation Administration, Bryan Bedford, said he expected the system to be back to normal by Monday (New Zealand time), although some delays were likely to continue for a few more days as airlines worked to get passengers to where they needed to be.
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