Air traffic chaos caused by ‘one in 15 million’ event

The air traffic chaos, sparked by a glitch in the UK’s air traffic control system, was bought down by a “one in 15 million” event, its boss said. 

The system shut itself down after receiving highly unusual duplicate “markers” on a flight plan. 

It led to hundreds of flights being delayed or cancelled as a result on 28 August, a bank holiday, and the day after. 

The company Nats – which controls the UK’s air traffic services, said it had never happened before. 

Newly released details have revealed how part of the UK’s air traffic control system shut itself down automatically in just a matter of seconds after the rare error. 

Martin Rolfe, chief executive of Nats, said that the system did “what it was designed to do, i.e. fail safely when it receives data that it can’t process”.

He described it as “a one in 15 million flight plan that we received”, meaning the engineers took a few hours to work out a situation they were not familiar with.

It was the first time this had happened in the five years the software had been operating, having processed more than 15 million flight plans, he said.

Nats said it had taken measures to prevent the situation from happening again.