Computer Weekly has learned that, because of the shortage of controllers at Swanwick only 18 to 22 main tactical radar positions - used by controllers when talking to pilots - are being manned, compared with up to 24 last year at West Drayton. Swanwick took over higher level flights over England and Wales from West Drayton in January.
The main business justification for the £623m Swanwick air centre, about £337m of which was spent on systems and software, was to provide an increase in capacity of between 30% and 40% over West Drayton while boosting margins of safety.
But Swanwick needs more staff to run the same number of air space sectors than the West Drayton centre. This is a particular problem at present because National Air Traffic Services (Nats) is short of 41 controllers.
Nats says the number of flights being handled by Swanwick in June was 4% below the levels managed by West Drayton in 2001, and in July was 3% below. "The airlines were aware that there would be no significant increases in capacity over West Drayton in the first year of Swanwick's operations," said a Nats spokesman.
However, delays for airlines this year have sometimes been double those of 2001. The Nats spokesman said this was due in part to the rapid and unexpected increase in the number of low-cost flights. He insisted that Swanwick was needed because West Drayton did not have the ability to meet the predicted growth in traffic.
But if staff shortages and major delays continue in the long term, Nats could be left in the increasingly challenging position of having to defend the cost of Swanwick and its advanced systems.