Britain From Above 1. 24 Hour Britain (9 of 28)

Britain From Above

Every day, more than 7,500 aircraft crowd into Britain's skies, carrying more than half a million passengers from every corner of this little green planet.
These are the GPS traces of every single plane entering British airspace over 24 hours.
And they're all following their own secret motorway system up in the sky - strictly laid out routes that run north and south, up and down the country and out over Europe and the Atlantic.
And dotted around the country, there are stacking systems, roundabouts in the sky, where they circle, waiting to land at one of our seven major airports.
These skies are being monitored every second of the day.
This is one of the Royal Navy's airborne early warning helicopters.

Suspended from the back is a state-of-the-art radar system that looks out over the horizon, further than any air traffic radar system on the ground.
Inside, observer Chris Barber can tell precisely where every aircraft should or shouldn't be.
Up here, we're very privileged.
We can look for hundreds of miles and see a God's-eye view of what's going on in a large area.
The red are all the danger areas.
That's where civilian and military air traffic is not allowed to go, when they're active, because there may be some gun-firing exercises, naval training exercises.
There may be air-to-air military training with RAF or Navy jets.