What Exactly Caused the Chaos?
On Tuesday, September 8, 2026, the UK's National Air Traffic Services (NATS) experienced a critical technical problem. The issue was located in its flight processing system, the software that automatically processes flight plans submitted by airlines.
While not a safety risk to planes already in the air, the system's failure meant that flight data had to be handled manually, a much slower process. This forced NATS to drastically reduce the number of aircraft taking off and landing, triggering a cascade of delays and cancellations across the country. NATS has ruled out a cyberattack as the cause.
The Scale of the Disruption
The impact was immediate and massive. In total, over 2,000 flights were cancelled across Tuesday and Wednesday, affecting hundreds of thousands of passengers. On Tuesday alone, more than 1,000 flights were cancelled. The disruption was centered on the UK's busiest airports, including London's Heathrow and Gatwick, as well as Manchester and Birmingham. The fallout was felt across Europe and beyond, as displaced aircraft and crews created a significant knock-on effect that took days to untangle. British Airways, the UK's flag carrier, and Ryanair were among the most heavily impacted airlines.
Impact on Flights to and from India
The chaos significantly affected travel between the UK and India. Airlines including Air India, IndiGo, and British Airways reported diversions, delays, and cancellations on these popular routes. On Tuesday, several Air India flights from Delhi, Mumbai, and Bengaluru bound for London were diverted to other European cities like Paris, Vienna, and Zurich. Consequently, the return legs of these flights to India on Wednesday were cancelled. IndiGo also had to divert two of its London-bound flights, which led to the cancellation of their return journeys to India. Air India issued a statement acknowledging the impact and advising passengers to check their flight status before travelling to the airport.
Is the System Back to Normal?
NATS announced that the technical issue was identified and a fix was implemented within hours on Tuesday afternoon. However, the recovery has been complex. By Thursday, September 10, schedules were beginning to return to normal, but the knock-on effects of repositioning aircraft and crews meant disruption continued for days after the initial fault. The UK government has demanded a full investigation from NATS, which is expected to deliver a report within a week. This incident marks the third major stoppage for NATS in just over three years, raising serious questions about the resilience of the UK's critical aviation infrastructure.
Your Rights as an Affected Passenger
If your flight was cancelled, your airline is obligated to offer you a choice between a full refund or an alternative flight to your destination at the earliest opportunity. If you are significantly delayed, the airline has a duty of care. This means they must provide reasonable assistance, including food and drink vouchers and, if necessary, overnight accommodation and transport to get there. However, when it comes to financial compensation for the inconvenience, passengers are unlikely to be eligible. The UK's Civil Aviation Authority (CAA) has stated that the air traffic control outage is likely to be considered an 'extraordinary circumstance,' which is outside of the airlines' control.
