All flights from Heathrow Airport are in disarray this morning as the new air traffic control centre at Swanwick experienced severe technical problems yet again.
The new centre, which went live in January five years late and £180m over budget, has already had to be upgraded several times.
A Heathrow spokesperson said: "The airport is subject to delays because of problems at air traffic control at Swanwick."
A spokesman at the Swanwick national air traffic control centre added: "A software upgrade was done last night which went well but, when it came to this morning, half the workstations did not turn on."
He explained that operations were running at 50 per cent of normal capability, but offered no further information regarding when the system will be fully up and running.
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