The Transport Secretary has told MPs she did not believe the air traffic control problems that have caused chaos for hundreds of thousands of passengers were “unavoidable”.
Travellers were caught up in the disruption after hundreds of flights were cancelled following the Nats technical issue on Tuesday.
Cancellations and delays continued on Wednesday as airlines dealt with knock-on impacts at airports including Heathrow, Gatwick, Manchester and Stansted.
Addressing the Commons on Wednesday afternoon, Heidi Alexander said: “A four-hour air traffic outage yesterday left hundreds of thousands of passengers facing cancellations, diversions, and delays.
“I would like to apologise wholeheartedly to passengers for this disruption.
“We often take for granted the way in which our aviation system just works, but yesterday that was not the case.
“Safety must remain air traffic controllers’ overriding priority, and this morning I have spoken to Nats chief executive Martin Rolfe, who informed me this outage was due to a technical issue at their Swanwick site.
“So, while my understanding from Nats is that we can rule out a cyber attack on this occasion, I do not believe this issue was unavoidable.
“We also spoke this morning about how Nats responded to resolve and minimise the disruption as quickly as possible, and I am grateful to the airports and airlines who responded straight away.”
Nats has apologised for disruption to passengers and airlines, for which Mr Rolfe said he took “full responsibility.”
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