By Richard Westcott
BBC Transport Correspondent
British air traffic controllers have invented a new system that could eventually cut flight delays all over the world.
The principle is simple enough. Planes coming into land will be spaced out by time, rather than by distance. But it has taken a team at NATS (formerly National Air Traffic Control Services) four years of scientific study to make sure it is safe, and Heathrow is about to become the first airport on the planet to test it out.
It all comes down to wind.
