Over 2,000 flights cancelled after Nats software defect, CAA to review
Transport Secretary Heidi Alexander has ordered an independent review after a coding error halted departures at Heathrow, Gatwick and other UK airports on 8 September.
News London evidence indexOpen analysis ▾
Trust 66: named Nats chief and Transport Secretary plus Nats report cited, but no independent outlets or figure sources.
Higher is stronger
Critic 80: clear impact, quotes, next steps, but article reads largely like a press release.
Higher is stronger
Hype 30: headline strong but body factual; mild emphasis without sensationalism.
Lower is better
On 8 September a software error in the system that automatically assigns identification codes to aircraft caused the cancellation of over 2,000 flights across the United Kingdom. The disruption affected passengers at Heathrow, Gatwick, Manchester and Stansted airports, among others. The National Air Traffic Services (Nats) released a preliminary report on the incident on 9 September.
What the fault involved
Over 2,000 UK flights cancelled after Nats technical fault, MOD denies military error
Transport Secretary says outage was not unavoidable while Nats launches investigation expected to finish next week
Nats explained that the faulty code‑allocation software normally generates a unique identifier for each aircraft when a manual request is entered. The error prevented the system from assigning these identifiers, which are required for radar tracking of flights in the airspace. Martin Rolfe, chief executive of Nats, told the Standard that the problem was a software issue and not linked to any prior outage or radar incident.
"I have now received Nats’ report and, while I am pleased to see that the safety of passengers was protected, it’s clear we need to urgently understand why this issue was not discovered and fixed before it caused chaos,"
Heidi Alexander, Transport Secretary
Heidi Alexander, Transport Secretary, described the disruption as "completely unacceptable" and said the incident caused frustration for travellers, airlines and airports. She added that the government will ensure the aviation sector is resilient enough to meet future demand.
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Government response and next steps
Following the Nats report, Alexander tasked the Civil Aviation Authority (CAA) with conducting an independent review of the findings and of Nats' investment plans for system resilience. The CAA is required to publish its report within six months of the appointment, according to the Standard.
Nats has faced renewed calls for leadership accountability after the incident. Rolfe apologised to affected travellers and to the aviation industry for the inconvenience caused. No evidence has emerged that military or civil operators contributed to the fault, as confirmed by Nats in its preliminary report.
Questions this report answers
+How many flights were cancelled because of the software defect?
More than 2,000 flights were cancelled on 8 September when the code‑allocation software failed. The cancellations affected several major UK airports and left hundreds of thousands of passengers stranded.
+Who is responsible for reviewing the incident?
Transport Secretary Heidi Alexander has asked the Civil Aviation Authority to carry out an independent review of the Nats report and the agency's future resilience plans. The CAA will produce its findings within six months.
+When will the review be published?
The Civil Aviation Authority is required to publish its independent review within six months of being tasked, as stated by the Transport Secretary in the Standard report.
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