The UK’s Civil Aviation Authority (CAA) has ordered an independent probe into an air traffic control meltdown on August 28, which grounded or severely delayed flights for several hours.
The inquiry was ordered shortly after the national air traffic control agency, which is known as NATS, released its own preliminary technical review into what caused the meltdown.
In a statement, NATS said on Wednesday that the technical issue had been traced to a one in 15 million chance events when a computer system attempted to process a flight plan that included two identically named but separate waypoint markers outside of UK airspace.
The computer system didn’t know how to process the flight plan and created a ‘critical exception’, which activated a failsafe system that stopped the automatic processing of all flight plans.
NATS said it took several hours for engineers to fix the issue because they had to “identify the problem and the specific data, isolate and remove it in a controlled way, and then test it to ensure it could be returned safely into operation.”
The computer system at the centre of the fiasco has been in operation for more than five years and has processed more than 15 million flight plans, but this is the first time that an event like this has occurred.
Nonetheless, the CAA said it would independently review the wider issues around the system failure and look at how NATS responded to the incident.
“The initial report by NATS raises several important questions and as the regulator we want to make sure these are answered for passengers and industry,” commented Rob Bishton, the CAA’s Joint-Interim Chief Executive, shortly after the technical report was published.
“If there is evidence to suggest NATS may have breached its statutory and licensing obligations, we will consider whether any further action is necessary,” Bishton continued.
The CAA expects its independent review to be completed by the end of September. NATS said safety was never compromised.
Ryanair blasted the NATS report in the incident, claiming it was full of inaccuracies and hit out at the agency for refusing to pay airlines compensation for huge expenses they incurred as a result of the meltdown.
