What does NATS do and how did the air traffic control issues happen?

The technical fault meant flight plans had to be input manually by controllers (Gareth Fuller/PA) (PA Archive)
The technical fault meant flight plans had to be input manually by controllers (Gareth Fuller/PA) (PA Archive)

Monday (August 28) has seen air travel in and out of Britain come to a complete standstill, with thousands of flights being cancelled and travellers being left stranded across the globe.

It was all caused by a “technical issue” the NATS was suffering from, which it said it “identified and remedied” yesterday afternoon.

In a statement, they explained: “We are now working closely with airlines and airports to manage the flights affected as efficiently as possible. Our engineers will be carefully monitoring the system’s performance as we return to normal operations.

“The flight planning issue affected the system’s ability to automatically process flight plans, meaning that flight plans had to be processed manually which cannot be done at the same volume, hence the requirement for traffic flow restrictions.

“Our priority is always to ensure that every flight in the UK remains safe and we are sincerely sorry for the disruption this is causing. Please contact your airline for information on how this may affect your flight.”

The incident has left many wondering what exactly the NATS does and how the technical fault happened. Here is a look at all the available information on the subject.

What is NATS?

NATS stands for National Air Traffic Services and provides en-route air traffic control services to flights, as well as controlling the air traffic in a number of UK airports.

It was originally created in 1962 and used to be co-managed by the UK’s military and civil servants.

In 1992, it was restructured to become a limited company and a wholly owned subsidiary of the Civil Aviation Authority in the country, ending the direct involvement of military officers in the management of the organisation.

Later, in 1998, it was proposed that NATS should be owned by public-private ownership. So, through the Transport Act 2000, 51 per cent of NATS was transferred to the private sector.

Over the years, things like the decline in air traffic following the 9/11 attacks have meant that the ownership percentages have had to change slightly in accordance with additional investments. But, the NATS is co-owned by the UK government, which holds the golden share, the Airline Group, the NATS staff, and the LHR Airports.

What does NATS do?

The primary duties of the NATS are to keep our skies safe by controlling air traffic, provide en-route guidance to flights via their control centres, and operate the air traffic procedures in a number of airports, including Heathrow, Luton, Stansted, and London City.

The company also helps the military across the globe with aeronautical data, defence consulting, military terminal assistance and surveillance, should they want to hire NATS.

What caused the technical glitch?

Thousands of passengers were left stranded in the UK and abroad on Monday after the technical failure across UK airspace, with more than 1,500 departing and arriving flights cancelled, according to Cirium, an aviation analytics company.

Transport Secretary Mark Harper told Sky News a technical fault on this scale hasn’t happened “for almost a decade”.

“Normally the system works very well and obviously [we] want to look to see if there’s anything we can do to avoid this disruption in the future,” he said.

Thus far, all that has been revealed is that the delays were caused by a technical issue. This meant that the NATS staff had to switch from their digital systems to analog systems while they worked out the problem. However, planning air traffic control is a lot slower when it isn’t digital, the company revealed.

The Transport Secretary shared that an independent review overseen by CAA would be due “in coming days”, which should reveal more about what caused the glitch and what steps could be taken to prevent it from happening again in the future.