Failed air traffice control system dates back to 70s

The software at the West Drayton centre in west London belongs to a programme that is no longer in production and which some computer experts have never heard of.

Experts said controllers were having to use a "patched-up system" and the present computer arrangement was "messy".

They also expressed surprise that National Air Traffic Services (Nats) - which has also been plagued by problems at its 623 million HQ at Swanwick, near Southampton, in recent years - had been carrying out overnight testing on an operational system rather than a simulated one.

Today’s problem centred on the flight data processing system and the software is based on the Jovial programme from the mid-1970s.

"Even some people in the computer industry have never heard of this programme as it goes back so far," said Tony Collins, executive director of Computer Weekly magazine.

He went on: "Although the hardware is new, the software is old. They have been upgrading parts of the software but it is very much a patched up system and that doesn’t help.

"It’s a little like adding new bits to an old car."

Mr Collins continued: "What is surprising is that they decided to open the Nats centre at Swanwick where the main data feed was being supplied by this old system.

"Some time ago, Nats told the House of Commons Transport Committee that the West Drayton system would not last beyond 2005. Then it was announced that the system would carry on until 2007 and now it is understood it will carry on until 2010-11.

"Controllers at Swanwick are having to get a feed from an old system. It’s a messy arrangement."

Mr Collins added: "There is also the question of why they were testing on an operational system rather than on a simulated one."

Today’s problem is just the latest in a series of difficulties that have hit Nats.

It has had to contend with the late opening of its Swanwick headquarters, numerous technical glitches, financial difficulties and a controversial and bitterly-opposed part privatisation.

Computer Weekly highlighted a series of problems, including the difficulty which some controllers had in reading numbers on their screens.

Swanwick was built to replace the West Drayton centre, which controls air traffic over south-east England and all traffic going in and out of London’s airports.