Heathrow Airport Flights Cancelled: What Went Wrong, Ongoing Disruptions and How It Could Affect Your Travel

Thousands of passengers experienced chaos at Heathrow and other UK airports on 30 July 2025 after a radar failure in London's air traffic control zone grounded all departing flights.

The technical glitch, described as a 'major problem' by the UK's National Air Traffic Services (NATS), disrupted operations at Heathrow, Gatwick, Stansted, and smaller airports, leaving travellers stranded and summer holiday plans in disarray.

While systems were restored by late evening, delays and cancellations continue to ripple through schedules, raising concerns about the reliability of UK air travel infrastructure.

What Caused the Chaos?

The disruption began around 15:00 BST on 30 July 2025, when a critical radar failure rendered London's controlled airspace unavailable, halting departures to ensure safety.

NATS confirmed the issue in a statement at 20:30, noting, 'The system in question has been restored, but restrictions remain to maintain safety.'

Heathrow, Europe's busiest airport, was hardest hit, with over 150 flights cancelled and hundreds delayed, according to The Independent. Gatwick reported 150 cancellations, while Stansted and Luton faced similar issues.

X posts from @aviationbrk stated, 'Gatwick and Heathrow have grounded all departing flights following a radar failure affecting the wider London area.'

Another from @ZT_Followers noted, 'Heathrow and Gatwick LIVE: All flights grounded as air traffic control collapses.'

The failure echoes a March 2025 power outage at Heathrow, highlighting recurring technical vulnerabilities.

Passenger Chaos and Airline Response

The outage stranded an estimated 100,000 passengers, with Heathrow's Terminal 5 seeing queues spilling outside.

Travellers faced significant delays, with flights diverted to Birmingham, Manchester, and European airports like Paris and Geneva.

Passenger John Carr, a 35-year-old from Stourbridge, told PA News, 'I'm pretty gutted. We've got loads of stuff in the suitcases to set up the venue,' after his Heathrow flight to Norway for his brother's wedding was cancelled.

British Airways restricted flights to 32 per hour at Heathrow, resuming normal levels by 19:15 BST. EasyJet's David Morgan said, 'It's extremely disappointing to see an ATC failure once again causing disruption to our customers.'

Airlines offered refunds or rebooking, but limited summer capacity exacerbated frustrations. The financial impact is estimated at £7.5 million ($10 million) for Heathrow, based on daily revenue averages.

Passengers like Tanya Goldhaber, reported, 'My child went into meltdown for a little while which wasn't great but she's sleeping now'.

Ongoing Disruptions and Systemic Concerns

NATS restored systems by 17:20 BST, stating, 'Our systems are fully operational and air traffic capacity is returning to normal.' However, knock-on delays are expected through 1 August 2025, as airlines clear backlogs.

Transport Secretary Heidi Alexander told Sky News, 'I am aware of a technical issue which impacted NATS operations causing travel disruption this afternoon,' advising passengers to check flight statuses.

The Liberal Democrats' Ed Davey called for an investigation, saying, 'It is utterly unacceptable that air traffic control has once again been hit by a technical fault.'

The incident, following a March 2025 Heathrow power outage, underscores infrastructure vulnerabilities.

As Heathrow and other airports recover, the incident underscores the fragility of global travel networks, with passengers bearing the brunt of systemic failures.

With a US trade deadline looming on 1 August 2025, potentially raising transatlantic fares, travellers are urged to monitor updates, arrive early, and secure travel insurance to navigate ongoing disruptions.