Revealed: Ageing computer system ‘is to blame’ for air traffic control meltdown as passengers may have been condemned to sleeping on airport floors when controller put too many DOTS in a flight plan request, expert says

An aging computer system was blamed for the air traffic control collapse today, as an expert claimed the chaos may have erupted because a controller put too many points in a flight plan request.

The widespread disruption that began Monday is believed to be caused by a single fraudulent flight plan.

Controllers need basic information about each flight to populate their display, such as the flight number, aircraft type, destination and route.

If these details aren’t spaced and formatted in a certain way, and the computer doesn’t recognize the data, it could cause a system crash – a failure described this morning by former British Airways boss Willie Walsh as ‘mind-boggling’.

Michele Robson, who has worked in air traffic control for more than 20 years, told the Sky News Daily podcast: ‘If there have been mistakes in the past, it’s normally due to bad information entered in the wrong format.

“It’s a very old system, it’s been running for years and overall we’ve been very lucky and don’t have failures very often, and when it does, we get it back during backup time, and there it is for .

“There have been other cases where something is formatted incorrectly and the flight plan computer behaves in a way they don’t expect and effectively causes it to fail, so that could be enough to potentially crash the system if it were to be formatted incorrectly.

‘You have to spread things out in a certain way, for example with a certain number of points. They do it in a very unique way that has never been done before or it would happen every day.

“So it must be something pretty unusual that they put in place to make it happen but it’s an old system and maybe something was put in yesterday that’s never been seen before and that’s what caused it to get this response where it failed .’

Martin Rolfe, CEO of National Air Traffic Services, was asked this morning on BBC Radio Four’s Today program why the problematic flight details were not rejected by Nats ‘as a piece of spam’.

He replied: ‘Our systems are safety critical systems, they deal with the lives of passengers and the traveling public.

“So even things like just throwing data away need to be considered very carefully.

“If you throw out a critical piece of data, within thirty seconds, a minute, or an hour you might find something that doesn’t make sense on the screens in front of the controller. So it’s nothing like throwing spam away.’

Asked about the age of the system and how often it needs to be updated, Mr Rolfe added: ‘We have a full program and we invest £100 million a year in new systems and we are constantly evaluating which systems need to be replaced and when.

“This is clearly a complex system with security at its core and the part of the system we are discussing was replaced quite recently, about five years ago.”

When the outage was first noticed on Monday morning, the system went into backup mode — which stores up to four hours of data — to prevent air traffic controllers from getting false information.

Because the bosses quickly realized that the problem would not be solved within that four-hour period, they decided to switch to a manual system, which required all flight plans to be entered individually.

This time-consuming process left air traffic controllers unable to handle even a percentage of the usual number of aircraft flying to and from UK airports.

The system was fully restored by 2.30pm on Monday, Mr Rolfe said, but the domino effect continues to be felt by passengers, who have been condemned to sleep on the airport floor as they desperately wait for their rescheduled flights.

Aviation analysis firm Cirium said 64 flights scheduled to fly into UK airports today were canceled as of 9am – after some 1,585 flights were canceled on Monday and another 345 on Tuesday.

Former British Airways boss Willie Walsh said it was “mind-boggling” that the system collapsed due to incorrect data.

Mr Willie, director general of the international aviation organization International Air Transport Association (IATA), told BBC Radio 4’s Today programme: ‘I find it staggering, I really do.

“This system should be designed to reject incorrect data, not crash the system.

“If true, that shows significant weakness that must have been there for some time and I’m surprised if that’s the cause.

“Obviously we’re waiting for the full evaluation of the problem, but that statement doesn’t match what I know about the system.”

It comes as it emerged that Martin Rolfe, CEO of National Air Traffic Services, saw his wages double to more than £1.3 million last year, after receiving pension benefits, an annual bonus of £281,000 and a long-term bonus of £555,000 retroactive. power. plan.

Mr Rolfe declined to comment on whether NATS – or himself after his personal windfall – will have to pay as a result of the disruption.

“At this point, my focus was entirely on making sure we restored the system, which we did on Monday, when we got back to normal at 2:30 p.m.,” he said.

“We have been working closely with the airline CEOs, many of whom I have spoken to directly, to make sure that we absolutely get everyone to their destination as quickly as possible, but most importantly, as safely as possible. ‘

Mr Walsh estimated the chaos will cost airlines around £100 million.

He said, “It’s very unfair because the air traffic control system that caused this failure isn’t paying a penny.”

The impact continued today: another 42 flights to or from Heathrow were cancelled.

Many affected travelers are being told to wait several days for a flight home.

Some have been forced to sleep on airport floors or travel long overland routes after their flights were cancelled.

Airlines were criticized for failing to book hotel rooms for many people who were delayed overnight.

Rory Boland, editor of consumer magazine Which? Travel said: ‘We are seeing worrying reports of passengers being left stranded without assistance and airlines failing to properly communicate with their passengers or comply with their legal obligations, such as offering timely re-routing or overnight accommodation.

In particular, travelers should be aware that their airline has a responsibility to reroute them as quickly as possible, even if it means buying a ticket from a competing airline – a rule some airlines appear to be ignoring.

“Passengers must also be provided with food and drink and accommodation if necessary.”

EasyJet operates five repatriation flights to Gatwick, with the first two departing today.

The airline said: ‘During this traditionally very busy week of travel, options to return to the UK are more limited on some routes and so easyJet will operate five repatriation flights to London Gatwick from Palma and Faro over the next few days on 30 August. and Tenerife and Enfidha on August 31, and from Rhodes on September 1.

“We are also operating larger aircraft on key routes including Faro, Ibiza, Dalaman and Tenerife to provide around 700 additional seats this week.”

It is speculated that the ATC malfunction was caused by a French airline submitting a flight plan to Nats in the wrong format.

Downing Street did not rule out that possibility, while Nats declined to comment on whether that had happened.

The issue resulted in flights to and from UK airports being restricted for several hours on Monday afternoon while flight plans were checked manually.

This caused the cancellation of about 1,500 flights on Monday, while another 300 were scrapped on Tuesday because aircraft and crews were out of place.

Mr Rolfe said Nats is working closely with the Civil Aviation Authority to prepare a preliminary report on what happened to Transport Secretary Mark Harper.

The conclusions of the investigation will be made public, he added.