The ageing Boeing 767 is on approach, descending you feel the odd bump as your aircraft passes through the clouds. It’s been a smooth flight, with the average 2013 standard service, but importantly you’re on schedule. Then, the flight crew announce they’ve slowed down as a result of air traffic restrictions. There is a collective groan, you roll your head back against the seat and push your iPod earphones back into your ears.

You’re delayed, it’s inconvenient, but how often do you take a moment to visualise the huge amount of aircraft in the sky around the aircraft you’re sitting on?

These time-lapse videos shot at San Diego International Airport and London Heathrow provide an incredible visualisation of the fast growing number of aircraft movements, a result of the increasing demand for air transportation around the world.

To give some perspective. In 2012, San Diego only handled 17.2 million passengers on an average 509 movements per day or approximately 215,000 in 2012. In comparison, London Heathrow handled 69.9 million passengers on 471,341 movements or 1,300 per day in 2012. Both airports operate with night curfew restrictions.

These time-lapses show only a fraction of the movements on any given day. Next time you fly, give some consideration to the coordination it takes to move these aircraft safely, and what you’re missing outside when you choose to sit in an aisle seat.