We have here an airport with two intersecting runways and a helicopter landing zone. The air traffic only arrives, there’s no departures. When a new aircraft is about to enter the screen, a red exclamation mark will appear near the screen border. Then you should press the mouse button on the plane (or helicopter), draw a line of flight and release the mouse button. If the trajectory drawn ends on the runway threshold or a landing zone (for copters), the aircraft will land successfully.