The UK’s worst air-traffic outage in a decade was caused by an anomaly in the airspace manager’s software system, which confused two geographical checkpoints separated by some 4,000 nautical miles. From a report: The UK’s Civil Aviation Authority said Wednesday it will conduct an independent review of the incident, which forced hundreds of flights to be canceled or delayed last week after an error in processing an airline’s flight plan. The glitch triggered a shutdown of the software system run by NATS for safety reasons, according to a preliminary report from the public-private partnership formerly called National Air Traffic Services. This forced air-traffic staff to input flight plans manually, drastically reducing the amount of air traffic that could be processed.
The event sent airlines and airports in the UK into turmoil on Aug. 28, leaving planes out of position and passengers stranded. Nearly 800 flights leaving UK airports were canceled, with a similar number of arrivals scrapped, according to analytics firm Cirium. The report by NATS showed that on the day of the incident, an airline entered a plan into the system which led through UK airspace. NATS Chief Executive Officer Martin Rolfe declined to discuss details of the flight, such as its route or the airline involved, saying the specifics weren’t pertinent to the outage. While the flight plan wasn’t faulty, it threw off the system because the software used by NATS received duplicate identities for two different points on the map. There are an infinite number of flight-plan waypoints in the world, and duplicates remain despite work to remove them, according to Rolfe.