How to combine lots of picture onto one base picture?

[Blighty]

A image like that requires a lot of work.

What you need:
1) An image of the airport
2) An image of each plane - 50 or 60 of them.

For each plane
1) Make a selection of the plane
2) Invert the selection
3) Delete the background
Knowing how to use the selection tools is a must here.

Now place all planes onto the airport image - each plane on its own layer.

See this one here:
https://www.gimp-forum.net/Thread-Off-th...taking-off