Simon Calder: Slicing the sky ever more thinly

The Man Who Pays His Way

"Never mind the outlook, try the uplook", advises the sign outside a Baptist church near Athens, Georgia, US. Look up to the skies over Europe this week, and you could be witnessing a revolution. But the people behind the most radical changes in air-traffic control in 50 years would rather you didn't notice a thing – that will mean the switch has been thrown painlessly.

Starting on Monday morning, the string that holds together the West Drayton air-traffic control centre near Heathrow will begin to be unravelled. (Rumour has it that some of the antiquated equipment that currently choreographs 747s over Britain is being shipped straight to the Science Museum.) Next weekend, the "New En-Route Centre" at Swanwick in Hampshire will take control of planes flying to, from and over the UK.

The centre is long overdue, in two senses. First, the Swanwick centre is six years late in opening. Next, the technology supporting air-traffic controllers in West Drayton is hardly more sophisticated than a Space Invaders machine, and not entirely reliable; tens of thousands of travellers were grounded in June 2000, when the mainframe failed and Britain's skies temporarily closed down.

National Air Traffic Services (NATS) – the public-private partnership which controls the skies over Britain – is confident of a smooth transition to a system capable of handling increased demand for air travel. From a sneak preview, the omens are good: the new centre looks less like the backdrop to an Ealing comedy and more like a set from Thunderbirds.

So how much will air-traffic delays reduce from next weekend, thanks to the new centre? Er, not at all. Initially, indeed, the queues in the skies could well get longer. During the first 10 weeks of the operation, the maximum capacity of each sector of sky over Britain will be reduced by 30 per cent. This is the equivalent of grounding three flights out of every 10. The idea is to minimise the strain on controllers as they adapt to their brave new world.

NATS stresses that most of the time, the number of aircraft in each chunk of airspace is below the new, lower limit. Air traffic is lighter in winter than summer, and since 11 September hundreds of flights have been deleted from the schedules. But your flight delay may still be ascribed to air-traffic control. The staff are easy – and anonymous – targets for apportioning blame for late-running flights, whether or not it is their fault.

You wait half a century for an air-traffic control revolution, and two come along at once. On Thursday, planes will start flying over continental Europe at heights they have never tried before. This is all the work of Eurocontrol, the space-age centre in Brussels that looks like the bridge of the Starship Enterprise and also takes the rap for plenty of delays. It is slotting extra layers into the skies above 29,000 feet, by reducing "vertical separation minima" – in short, squeezing in more planes.

At present, pilots are obliged to fly 2,000 vertical feet apart. But smarter instrumentation makes controllers more confident that pilots can maintain the assigned height with precision. So they are cutting the minimum to 1,000 feet, and squeezing in six more flight levels.

Passengers can look forward to journeys that are more comfortable as well as less delay-prone; previously, some captains were obliged to keep low to avoid the congestion at altitudes where the skies are smoother; now they can fly above the crowds.

The result, says Ian Jones – who runs Eurocontrol's Flow Management Division in Brussels – is like adding several lanes to a motorway. But that doesn't mean that air-traffic delays will be eliminated at busy times.

From his omniscient view as traffic cop for the skies of Europe, Ian Jones says his purpose is: "To make sure the passenger arrives where they're trying to go as near to the time they want to.

"It's like the M25. Anyone who goes on to the motorway at five o'clock on a Friday evening knows how traffic snarls up." The analogy of Europe's skies, he says, is identical: "We offer people alternative routes via Epsom and Chessington." Some solutions, he says, are more radical: "Overflying or tunnelling underneath the M25."

Once all the available space has been filled, though, the people who co-ordinate flights over Europe have to say, "Don't leave now, leave in half an hour and you'll have an uninterrupted journey to your destination."

These welcome, and expensive, improvements may speed your passage over Europe, but could just mean you reach the stack of planes queuing for Gatwick or Heathrow that much sooner. With only three runways between them, Britain's busiest airports are hard-pressed to meet the demands of the 21st century. So expect to spend plenty of time circling over the Home Counties, enjoying repeated views of Biggin Hill, Bovingdon, Lambourne and Ockham – the hapless villages over which aircraft burn up fuel while waiting to land.

There is still some extra capacity to be squeezed out of the skies, particularly over the former Soviet bloc. But many thorny problems need to be solved before the dream of a "single European sky" comes true.

Air traffic is one rare activity where imperial measures are accepted as standard worldwide. Or for most of it. Controllers back in the former USSR do not recognise the industry standard of feet; they insist upon metres.

Simon.Calder@independent.co.uk