International Airport -- Only 1 runway used???

[Stringer Bell]

I didn't notice it before but apparently all the planes are only landing on one of the runways at my international airport. I tried to place it facing different directions, even bulldozed an entire district just to move my airport there as a test, but it's still the same. Planes will always only land on and take off from one of the runways. I loaded an earlier city that I built and it's the same deal (funny I never noticed it until now) -- anyone has the same problem and know how to fix it? What's the cause???

Thank you!

[AoD_lexandro]

Your runways need to be lined up with multiple air routes for both to be used. If one runway is lined up to the "main" point where air routes converge, only one will be used.

[Stringer Bell]

Ha??? Thanks, but how do I know where the air routes are?

[Stringer Bell]

I mean, I know I can click on the route view but all I can see a few purple lines going to one of the runways. And then it links to a line running over the city. I am not sure I know how to line my airport up with multiple air routes. Any adivce will be most appreciated!

[Stringer Bell]

This airport thing is just ruining my whole CS experience. I spent hours moving the airport and rotating it and testing it and it never manages to link up with the air routes with more than one runway, it's almost like there's a bug. And then one time I manage to have it link up with two runways, but it feels like such a fluke, like my city is plagued by a bug and my airport now cannot be moved or else I lose the fluke connections I get that one time.

I can't help but think there must be some logic about it that I miss. Anybody has any ideas? I made a screencap of my airport and the air routes:

https://imgur.com/a/T0K5B

[AoD_lexandro]

Your runways only work in one direction for landing, if only one end is the closest point it gets used. The international airport is intended for maps with 4 incoming air connections, so you can have a N/S runway and an E/W runway.

If your not sure where the incoming air connections are on the map, have a look at it in the editor and see where aircraft are going through the map. Then work around that and figure out a good place to plonk it down to match the air connection routes.