Ministry of Defence denies military jet caused air traffic failure

The Ministry of Defence has denied a report that a military aircraft was to blame for an air traffic control system failure that caused widespread travel chaos earlier this week.

A flight plan submitted by a British military aircraft caused the outage, which led to the cancellation of more than 2,000 flights, the Financial Times reported on Friday, citing sources familiar with the incident.

The data entry caused a glitch in the system operated by National Air Traffic Services (Nats) on Tuesday, which took hours to restart, according to the newspaper.

A Ministry of Defence (MoD) spokesperson said: "We do not believe there's any indication of an error on the part of the military.

"Because it's subject to a live Nats investigation, which is expected to conclude next week, it would be inappropriate for us to comment any further while that investigation is ongoing."

A spokesperson for Nats - in which the government has a controlling interest - said it was still investigating the cause of the glitch and that it "would be wrong to speculate while that work continues".

Hundreds of thousands of people are thought to have been affected across two days of end-of-summer travel chaos after the system went down for four hours on Tuesday.

Flights in and out of the UK's main airports were affected, including Heathrow, Gatwick, Luton and Glasgow.

While Nats is expected to report back on its own investigation on Wednesday, Transport Secretary Heidi Alexander has also ordered an independent probe by the Civil Aviation Authority.

The watchdog said earlier this week that passengers were unlikely to be entitled to compensation after would-be travellers told the BBC of nightmare delays and waylaid holiday plans.

Airlines are not necessarily liable to compensate passengers for disruption caused by air traffic control.

After meeting the head of Nats, Alexander said a cyber-attack could be ruled out but added: "I do not believe this issue was unavoidable."

Nats has apologised for its third major technical fault in three years, after a computer shutdown over the August bank holiday caused travel chaos for 700,000 people in 2023 and smaller outage in 2025 caused 150 flight cancellations.

Nats is a public-private partnership, with the government holding the controlling stake of 49%. The rest is split between a group of UK airlines including BA, easyJet and Virgin Atlantic, as well as Heathrow and Nats staff.