UK Air Traffic Disrupted by Radar Issue, 150 Flights Cancelled.

A technical glitch at UK air-traffic control caused by a radar issue led to 150 canceled flights, affecting London Heathrow and other airports during a busy travel period. The issue was resolved by switching to a backup system, but the outage caused frustration for holidaymakers and airlines. The UK government is investigating the incident, with Transport Secretary Heidi Alexander meeting NATS CEO Martin Rolfe to understand what happened.

A brief radar-related issue at the UK's air traffic control system, managed by NATS, caused significant disruptions across the country on Wednesday, July 1, 2025. The outage, lasting just 20 minutes, led to the cancellation of 150 flights and widespread delays, affecting major airports including London Heathrow [1].

The fault was attributed to a problem with the radar display system in NATS' national air traffic control center in Swanwick. NATS quickly switched to a backup system to resolve the issue, but the brief outage caused significant chaos, with passengers and airlines expressing frustration [1]. The Transport Secretary, Heidi Alexander, described the incident as an "isolated event" with no evidence of a cyber attack [1].

The incident is not the first major outage NATS has faced. In August 2023, a similar issue resulted in over 700,000 passengers being affected and 500 flights canceled. Airline operators, including Ryanair and EasyJet, have criticized NATS' performance, with Ryanair calling for the resignation of NATS CEO Martin Rolfe [1].

Graham Lake, a former director general of the Civil Air Navigation Services Organisation (CANSO), explained that the NATS air traffic network is like "national infrastructure" and that radar failures can degrade the network's capability, leading to significant delays and cancellations [1].

The UK government is investigating the incident, with Alexander meeting with NATS CEO Martin Rolfe to understand what went wrong. The Department for Transport (DfT) noted that it does not have direct control over NATS and that the government is working closely with NATS to address the issue [1].

The disruption comes at a busy time for UK air travel, with Heathrow Airlines Operators Committee calling for more runways in the southeast of England to increase capacity [1]. However, critics argue that expanding airports would increase emissions and air pollution [1].

References:
[1] https://www.bbc.com/news/articles/clyv75g60ejo
[2] https://www.standard.co.uk/news/london/air-traffic-control-problem-flights-cancelled-heathrow-gatwick-stansted-b1240833.html