London — A technical failure at the UK’s National Air Traffic Services (NATS) Prestwick centre in Scotland disrupted flights across northern parts of the country on Monday, 21 September 2026, leading to roughly 200 cancellations and widespread delays. The issue was resolved by mid-morning, but knock-on effects continued through the day and could affect some operations into Tuesday.
NATS described the problem as a “connectivity issue” unrelated to the major software defect that grounded or delayed more than 2,000 flights earlier in September (around 8 September). Engineers fixed the Prestwick fault, and the system returned to full capacity, though residual delays arose as aircraft and crews were repositioned.
Affected Airports and Scale
Disruption was concentrated in Scotland, Northern Ireland and northern England. Manchester, Glasgow, Edinburgh, Belfast International and George Best Belfast City airports reported the heaviest impact, with delays of up to several hours and notable cancellation rates (for example, more than 17% of departures affected at Belfast City at one point). Some disruption also reached London Gatwick, London City and other routes heading north. Airports south of Manchester were described as broadly less affected.
Aviation analytics firm Cirium estimated around 200 UK flights were cancelled or did not operate. easyJet was the most impacted carrier, with about 47 of its 670 scheduled UK departures cancelled. British Airways and Ryanair also reported cancellations and delays; Ryanair said roughly 25,000 of its passengers faced disruption.
Official Response
Transport Secretary Heidi Alexander confirmed the problem had been fixed and systems were resuming, while acknowledging passenger frustration so soon after the previous outage. NATS apologised and urged travellers to check flight status directly with their airlines. The Civil Aviation Authority indicated that passengers are unlikely to be entitled to compensation under EU/UK rules because the disruption stemmed from air traffic control rather than the airline.
Airlines renewed criticism of NATS resilience and called for greater accountability. Pressure continued on NATS chief executive Martin Rolfe following repeated incidents in recent years.
Passenger Advice
Travellers flying on or around 22 September should monitor airline apps, websites and airport updates closely, as residual delays and schedule recovery can extend into the next day. Allow extra time at airports, especially for connections involving Scotland, Northern Ireland or northern England. Those already affected on 21 September should contact their airline regarding rebooking, refunds or care provisions.
This marks the second significant NATS-related disruption in under two weeks, following the larger September outage caused by a software defect that corrupted flight data in milliseconds. Temporary traffic restrictions maintained safety throughout Monday’s incident.
