NATS’ preliminary technical report sets out the causes of the issue and actions taken to rectify and mitigate the effects. It found the incident occurred due to an anomaly that forced the system to stop processing flight plans. The system was closed to maintain safety and required manual operation to continue service.
The UK Civil Aviation Authority will now independently review the wider issues around the system failure and how NATS responded to the incident.
If there is evidence that suggests NATS may have breached its statutory and licensing obligations, the UK Civil Aviation Authority will take any appropriate steps.
The review will also set out lessons to be learned for the future for the benefit of consumers and the industry.
Rob Bishton, Joint-Interim Chief Executive at the UK Civil Aviation Authority, said: “Millions of passengers every year rely on air traffic control to work smoothly and safely. The initial report by NATS raises several important questions and as the regulator we want to make sure these are answered for passengers and industry.If there is evidence to suggest NATS may have breached its statutory and licensing obligations we will consider whether any further action is necessary.”
The scale of the disruption that followed was significant and meant some passengers faced long delays, in some cases, waiting several days for alternative flights.
Airlines worked around the clock, putting on extra capacity to resolve the issue. Airlines have obligations to look after their passengers in these circumstances and bring them home as soon as possible.
NATS shared its preliminary technical report on the failure with the UK Civil Aviation Authority on Monday (4 September) and the regulator sent it to the Secretary of State for Transport, Mark Harper and Aviation Minister, Baroness Vere outlining its next steps.
Details of the independent review will be published by the end of September 2023.
Transport Secretary Mark Harper said: "I welcome NATS’ preliminary report outlining the facts of last week’s air traffic control technical failure – particularly the confirmation that there were no safety issues as a result.I also welcome the announcement from the Civil Aviation Authority (CAA) of an independent review to dig deeper into this event and understand whether there are any further steps to be taken to improve the resilience of the air traffic control system.Thousands of passengers faced disruption as a result of the failure, with over 1500 flights cancelled and hundreds more delayed. I once again want to echo NATS’s apology to those who were caught up in it, with a technical fix now identified to ensure that such an incident does not recur."
