Staff preparing the £699m New En Route air traffic control centre at Swanwick for a go-live date of 2001 have hit a new safety-related communications problem that has no immediate solution.
Although the site's owner National Air Traffic Services (Nats) is confident that a solution will be found, the difficulty underlines the risks to the go-live date, and to the Government's plans to privatise Nats before the Swanwick air traffic control centre is due to go into operation.
By the end of this year Nats hopes it will be ready to show demonstrations of the operational system to bidders. Chief executive Bill Semple believes that bidders will see that the Swanwick project is world-beating.
However, the system is not due to become operational until November 2001, some months after the sale of Nats, which is scheduled for the first quarter of next year.
In view of the technical uncertainties, some bidders have indicated that they will seek to offer prices which substantially discount the Swanwick centre. But Nats officials said the Government is unlikely to accept such bids.
The latest estimate of Swanwick's total cost is £699m, a figure which represents more than the £650m the Government is said to be seeking for Nats.
Although the unforeseen communications glitch could be an early indication that other project issues are lying undetected, Nats remains confident that nothing will stand in the way of the winter 2001/2002 target date.
The communications problem centres on the need for voice messaging systems at the Swanwick site to link into legacy equipment at the existing London Air Traffic Control Centre. This complicates and slightly delays the routing of voice messages, leading to an intrusive "sidetone" echo in the headphones of controllers.
Clear communications are vital, not least because misunderstood messages bet-ween air traffic controllers and pilots have been a contributory factor in some of the world's worst air crashes.
Easy ways around the problem involve small compromises in safety, so staff are continuing to look at other possible solutions.
Nats said the communications problem is a "marginal" safety issue. "We are confident we can crack it," said a spokesman.