As planes finally return to the skies after days of delays and cancellations, the mystery behind the UK air traffic system breakdown appears to be rooted in the mismanagement of flight data.
The chaos, which hit thousands of late-summer holiday-goers this week, saw most UK flights being cancelled across the country in what Transport Secretary Mark Harper described as the worst incident of its kind in almost a decade.
Government ministers initially included a cyber attack as the possibility of the network failure, following a breach by pro-Russian cyber attacks in April on Eurocontrol, the organiser of commercial traffic in the European Union.
But a statement from National Air Traffic Services (NATS) Chief Executive Mark Rofle revealed that initial investigations showed that the problem "relates to some of the flight data we received."
"Our systems, both primary and the back-ups, responded by suspending automatic processing to ensure that no incorrect safety-related information could be presented to an air traffic controller or impact the rest of the air traffic system.”
Mr Rolfe did not elaborate on which exact data caused the conundrum, but multiple media outlets reports say that the system shutdown is being blamed on an airline’s inaccurate flight data entry submission. This reportedly led to the system reverting to manual processes and causing flight cancellations.
The NATS chief later described the issue as "incredibly rare", saying he was confident the situation would not arise again. "We understand the way the system didn't handle the data… the way it failed”
‘Significant’ Charges Looming
The revelations follow a meeting of NATS, the Civil Aviation Authority (CAA), airlines, airports, trade bodies and the Border Force, chaired by Transport Secretary Mark Harper.
Speaking after the meeting, Mr Harper warned again that the knock-on effects of Monday's disruption are likely to continue over the coming days, and said passengers due to travel should check with their airlines before heading to the airport.
The NATS Air Traffic Control system at Swanwick cost £623million.
It was brought to its knees by a single flight plan being formatted incorrectly before being input. (No, it wasn't from France).
Even an Excel spreadsheet used for data entry has checks built in to prevent this.
— Bryan Smith #RejoinEU (@BpsmithUk) August 29, 2023
The head of one industry body said the organisation has "crucial questions to answer" over the fault, which Nats remedied three hours after confirming the issue just before 12:00 on Monday.
Willie Walsh, head of the International Air Transport Association, called the failure "unacceptable" and said he felt for passengers who continue to suffer "huge inconvenience" and airline staff put under "considerable additional stress".
He added that airlines would "bear significant sums in care and assistance charges, on top of the costs of disruption to crew and aircraft schedules. But it will cost NATS nothing."
A Lesson in Observability
The precise nature of that technical glitch that caused the disruption has yet to be fully explained, and may not come to light before investigators deliver a preliminary report to the Secretary of State for Transport next Monday.
But Oseloka Obiora, Chief Technology Officer at RiverSafe, says that network visibility across could have prevented much of the chaos.
“Downtime in industries such as aviation causes incredible disruption, as we’ve seen by flights being grounded and major delays, so it is vital that organisations have observability to monitor their entire network environment.
Effective network visibility through observability can be the difference between hours and days’ worth of delays in the aviation industry.
“Having visibility over the condition of networks, infrastructure and applications based on data outputs can ensure that IT teams are able to better identify and resolve issues faster.”
