Airports chaos caused by 'software glitch' officials find - as Government orders further probe but dodges sacking under-fire NATS boss

Airports chaos caused by 'software glitch' officials find - as Government orders further probe but dodges sacking under-fire NATS boss - See more Daily Mail on Google - save us as a Preferred Source An air traffic control system failure that led to thousands of flights being cancelled last week was caused by a software glitch, a preliminary report has found. The National Air Traffic Services (NATS) probe into the chaos on September 8 found the cause was a 'software malfunction in the space of a millisecond' in a small part of its system. This part of the software automatically allocates identification codes to aircraft when air traffic controllers request them. These codes are then used to identify flights while they are in the air. The preliminary findings, ordered by Transport Secretary Heidi Alexander, explain a request for a code was paused when the system received a message for a higher-priority task. When the code request resumed, the software defect meant it didn't restart correctly. This triggered the chain reaction that led to thousands of flights being grounded. The report also found the meltdown, which saw hundreds of thousands of passengers suffer cancellations or nightmare delays, was not caused by human error or any 'incorrect actions'. Ms Alexander said she had ordered the Civil Aviation Authority (CAA) to review NATS's findings. The Cabinet minister had given under-fire NATS boss Martin Rolfe a week to report back on the reasons for the grounding of more than 2,000 flights, having previously said she did not believe the issue was 'unavoidable'. She has so far dodged calls by airlines, including Ryanair and WizzAir, for a major overhaul of NATS and the removal of Mr Rolfe over repeated failures. Hundreds of thousands of passengers suffered disruption due to the 'software defect' on 8 September Last week's fault caused flights both in and out of the UK to be axed and saw some travellers forced to sleep on the floor at airport terminals The Government had given under-fire NATS boss Martin Rolfe a week to report back on the reasons for the grounding of more than 2,000 flights Mr Rolfe has received £2.2million in bonuses and incentive payments over the past three years despite two other high-profile failures in 2023 and last year. Passengers at Heathrow, Gatwick, Manchester and Stansted were all impacted by last week's fault, which caused flights both in and out of the UK to be axed and saw some travellers forced to sleep on the floor at terminals. In the report Mr Rolfe said at this stage he could confirm the incident was not related to the outage in 2023 or last July's radar issue. 'I can also confirm that it was a software issue and not caused by any incorrect actions by either military or civil operators,' he said. Mr Rolfe apologised again to travellers who were affected by the incident, as well for the challenges it caused to the aviation industry. 'This was a software issue in a specific part of our flight data system, that we have traced to a small subsection of coding,' he added. 'The issue has been identified and mitigation is in place while a permanent fix is safety tested and deployed.' Mr Rolfe promised a 'major incident report' would be completed within the next two months following a full investigation. 'Our primary focus, and the primary accountability under our licence, is the safety of all air traffic using UK airspace,' he continued. 'We will always do what is necessary to preserve that. That can mean placing restrictions to limit air traffic, as we did on 8 September; we do not do that lightly, and we deeply regret the inconvenience it caused to so many people.' In response to the preliminary report, Ms Alexander said: 'The disruption we saw last week was completely unacceptable and I know how frustrating it was for passengers, airlines and airports. '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. 'I have therefore tasked the CAA with conducting an independent review to check NATS' findings and investigate their investment plans to enhance resilience in the future, along with regulatory accountability. 'It is crucial that our national infrastructure is fit for the future, and this Government will make sure the aviation sector is as resilient as possible, so passengers can get to where they need to be.' The CAA report is due to be published within six months. Last July, a 'radar-related issue' caused an air traffic control failure which disrupted thousands of passengers and forced the cancellation of more than 160 flights. In August 2023, more than 700,000 passengers suffered disruption when flights were grounded at UK airports when NATS suffered a technical glitch while processing a flight plan.