Britain's aviation network has been hit by a second major air traffic control failure in a fortnight, cancelling more than 200 flights and renewing questions over the resilience of the systems handling one of Europe's busiest aviation markets.
The disruption on 21 September began with a technical problem at National Air Traffic Services' (NATS) Prestwick control centre in Scotland, affecting traffic across Scotland, Northern Ireland and northern England. Manchester, Edinburgh and Belfast were among the airports caught in the disruption, with knock-on delays and cancellations elsewhere in the UK.
By late afternoon, 227 flights had been cancelled, according to aviation analytics company Cirium, figures reported by Associated Press. Ryanair said more than 25,000 of its passengers were affected. For airlines still recovering from the earlier breakdown, it was an unwelcome repeat.
Two failures in a fortnight
On 8 September, a separate NATS systems failure caused far more extensive disruption. Nearly 2,100 flights to and from UK airports were cancelled, including about 1,750 on the first day of the outage, according to The Guardian. British Airways alone cancelled almost 550 flights, affecting more than 85,000 customers. Heathrow, the UK's largest international gateway, took a particularly heavy hit.
The effects stretched beyond holiday traffic. Arsenal's Champions League travel plans were disrupted by the earlier air traffic control problems — a reminder that failures on this scale quickly spill into corporate, group, sports and events travel. A preliminary investigation into the 8 September incident identified a software defect involving the allocation of codes to individual aircraft, The Independent reported.
NATS has said the latest Prestwick incident was unrelated to that failure. For airlines, however, the distinction does little to reduce the operational cost of two breakdowns within such a short period.
Airlines turn up the pressure
British Airways, easyJet, Jet2 and Ryanair were among the carriers raising concerns following the latest disruption. Ryanair again called for NATS chief executive Martin Rolfe to resign, while easyJet questioned the resilience of Britain's air traffic control infrastructure, according to a report by The Guardian.
The consequences of an air traffic control failure rarely end when the technology comes back online. Aircraft are stranded away from their scheduled bases, crews can run out of permitted operating hours and airport slots are lost. Airlines then face the costly exercise of rebuilding schedules while finding seats for displaced passengers.
For the travel trade, the disruption travels further still. A cancelled flight can unravel hotel reservations, airport transfers, cruise departures, tours and onward connections. Travel management companies and agents handling multi-sector itineraries are often left rebuilding an entire journey rather than simply finding another flight.
Compensation remains a sticking point
Passengers may also find that a cancellation does not automatically bring financial compensation. The UK Civil Aviation Authority said the 21 September NATS disruption was likely to constitute “extraordinary circumstances”, which would generally put statutory compensation outside airlines' control. Carriers still retain obligations to look after passengers affected by cancellations and lengthy delays, including rerouting and providing appropriate care.
Transport Secretary Heidi Alexander had already commissioned an independent Civil Aviation Authority review following the first September outage. The second failure now gives that review a sharper industry context.
For airlines, airports and travel companies, attention will turn to whether the investigations produce changes to redundancy, technology and contingency planning at NATS. After two significant failures in a fortnight, the question facing Britain's aviation sector is no longer simply what went wrong on a particular day, but how quickly confidence in the resilience of the network can be restored.
