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
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On Tuesday a systems failure at National Air Traffic Services (Nats) halted the processing of flight plans, leading to the cancellation of over 2,000 arrivals and departures nationwide. The disruption continued into Wednesday, affecting passengers at major airports including Heathrow.
Background to the outage
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The Standard reported that the glitch followed a flight plan entry that, according to four unnamed sources, originated from a military aircraft. The Ministry of Defence (MoD) responded that it does not believe any error on the part of the armed forces contributed to the failure. The agency added that, because the matter is subject to a live Nats investigation, further comment would be inappropriate.
In August 2023 a similar Nats technical problem grounded flights and disrupted more than 700,000 passengers. That earlier incident highlighted the vulnerability of the UK’s air traffic management system to software faults.
Official statements
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Transport Secretary Heidi Alexander addressed the House of Commons on Wednesday afternoon, stating she did not consider the air‑traffic control issue to be "unavoidable". She urged the regulator to accelerate remedial work to prevent a repeat. A Nats spokesperson said the organisation is continuing its technical investigation and warned against speculation while the probe proceeds.
I take full responsibility for the incident.
Martin Rolfe, chief executive, Nats
Industry reaction
Ryanair chief Michael O’Leary called Mr Rolfe’s position "untenable" and urged the board to consider leadership change. Wizz Air issued a statement describing the Nats failure as "extremely disappointing" and saying the provider is "not fit for purpose in its current form".
What comes next
Nats has said a full technical investigation will be completed by next week. The findings will be shared with the Civil Aviation Authority and the Department for Transport. Passengers whose flights were cancelled are advised to contact their airlines for rebooking or compensation under EU261 rules.
Questions this report answers
+How many flights were cancelled because of the Nats fault?
More than 2,000 arrivals and departures were cancelled across the United Kingdom after the technical issue at Nats on Tuesday. The scale of the disruption means many passengers will need to seek rebooking or compensation from airlines.
+Did the Ministry of Defence admit any mistake?
The Ministry of Defence said it does not believe there is any indication of an error on the part of the military. It also noted that the incident is under a live Nats investigation, limiting further comment.
+What did the Transport Secretary say about the outage?
Transport Secretary Heidi Alexander told MPs the air‑traffic control problem was not unavoidable. She called for swift remedial action and highlighted the need for the regulator to address system weaknesses.
+When will the investigation results be published?
Nats expects its technical investigation to conclude next week. The final report will be shared with the Civil Aviation Authority and the Department for Transport, and may inform future safety and system‑upgrade decisions.
News London Desk
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