Air Traffic Simulation

This is a air traffic simulator, designed to emulate an air traffic situation.

There are three buttons on the bottom right corner, and they each introduce a new type of plane.
The green planes are the normal planes; they fly in one direction, and change direction when they meet the edge of a world. They also slow down when the reach a cloud.
The red planes are the rogue planes; they fly randomly and may get stuck into the cloud.
The blue planes are the repair planes; they repair normal planes when they intersect with them.

When the rogue planes crash into the normal planes, they explode, and the plane will then spiral out of control. After a while, the plane will disappear, if not repaired.
You can introduce a repair plane and control it with the left and right keyboard buttons.
If the repair plane intersects with the plane in time, then the plane will revert back to normal.