Key facts
- A software defect caused the UK air traffic control system failure.
- The failure led to over 2,000 flight cancellations.
- Hundreds of thousands of passengers were affected by the outage.
- The defect occurred in the system that underpins the management of UK airspace.
- The problem happened in the space of a millisecond, producing corrupted data.
The UK's air traffic control system experienced a failure earlier this month, causing widespread travel disruption. The National Air Traffic Services (Nats) has now stated that the incident was caused by a "software defect." This failure led to more than 2,000 flights being cancelled and affected hundreds of thousands of passengers, with some facing overnight stays at airports or being stranded abroad. Major UK airports, including Heathrow, Gatwick, Luton, and Glasgow, saw their operations impacted. The incident prompted scrutiny over the robustness of Nats' systems and led to questions regarding the leadership of its chief executive, Martin Rolfe. The government had previously stated that a cyber attack was not the cause, and the Ministry of Defence has denied reports suggesting a military aircraft was responsible. Nats reported that the defect occurred in the system responsible for managing UK airspace, causing corrupted data to be produced in a fraction of a second. This reduction in available information led air traffic controllers to implement restrictions to ensure flight safety.