Ryanair has rejected the findings of the National Air Traffic Services’ (NATS) preliminary report into the UK’s air traffic control system failure in August, calling the findings a “whitewash”.

The airline has pointed to what it calls “numerous inaccuracies” in NATS’ preliminary technical report, which sets out the causes of the issue on Monday August 28th which led to widespread delays and cancellations, as well as the actions taken to rectify and mitigate the effects. 

According to the UK’s Civil Aviation Authority the NATS report found the incident occurred due to an anomaly that forced the system to stop processing flight plans.

The report says: “This is the root cause of the incident. We can
therefore rule out any cyber-related contribution to this incident.
Safety critical software systems are designed to always fail safely.” The system was closed to maintain safety and required manual operation to continue service.

The CAA 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 CAA will take appropriate
steps.

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 the incident on August 28th was significant and meant some passengers faced long delays, in some cases, waiting several days for alternative flights.

NATS shared its preliminary technical report on the failure with the CAA on Monday (September 4th) and the regulator sent it to the secretary of state for transport, Mark Harper and aviation minister, Baroness Vere, outlining its next steps.

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.”

The transport secretary will chair a further meeting between NATS, the CAA and the aviation industry tomorrow (September 7th 2023) to allow NATS to present its findings and consider initial feedback from airlines.

Ryanair’s Michael O’Leary has called the report a “whitewash” and said: “This preliminary NATS report is factually inaccurate. It ridiculously understates the number of flights that were cancelled or delayed through the NATS system failure.”

The airline says it had more than 370 flight cancellations (over 63,000 passengers) and more than 1,500 flight delays over the two days, with more than 270,000 passengers delayed. 

O’Leary added: “This whitewash report, which understates the number of flights cancellations and flight delays, fails to explain why one inaccurate flight plan brought down not just the NATS ATC system, but also the backup system.”

The CAA’s independent review will also set out lessons to be learned for the future
for the benefit of consumers and the industry. Details of the independent review will be published by the end of September 2023.