NATS said in a preliminary report released on 18 Sept that last week’s
widespread UK airport disruption — which forced cancellations of more than 2,000
arrivals and departures — was caused by a millisecond-level software fault. The
probe found a software error in the UK air traffic system on 8 Sept that
occurred within one millisecond and was not attributable to human error. The
affected system assigns flight identification codes used by controllers on
radar. The fault triggered mass cancellations and delays at major airports
including Heathrow, Edinburgh and Manchester, affected hundreds of thousands of
passengers and took several days to restore normal operations.
