Thanks a lot for your suggestions! Some of you are right
I’ve got the solution, I think:
A rwy in ACEO does not necessarily need two entries/exits. One is enough, if this is both entry and exit.
But that’s not enough. The logic in the game is based on the stand, not the runway. Every runway that is reachable for a stand has to be reachable for landing and take off, regardless of that the rwy is marked as landing-only or take-off-only.
Back to my airport, the problem wasn’t the runway direction mark or the entry direction, the problem was the one-way taxiway to the runway. This prevented that the runway can be used - theoretically - for both landing an take-off:
This game’s logic is realistic. Assuming a rwy could be used dependent on wind directions.
Not realistic is my runway design , but it’s based on the also not realistic possibility, to mark a runway as landing-only (or take-off-only) and the strange max capacitiy of only 6 flights per hour.
One more thanks for your help!