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I have had a couple of trains crash at a signalled junction that has been running fine for 50+ hours.
It may just be some very unlucky timings of trains arriving at the junction.

I first noticed a train backlog and found the collision and was able to get an auto save back to see the collision (which repeats each time the same game is loaded).

All trains are running on rocket fuel and all train research is complete.

There 3 trains involved that cause the issues on a 3 lanes of track at an intersection.
From what i can tell (using game speed 0.1) the iron train in lane 1 is planning on moving into lane 2 and the green circuit train in lane 3 is planning on staying in lane 3, but half way through the junction the iron train changes it route and wants to go into lane 3 and stops in the middle of the junction to let green circuit train through. The for some reason the blue circuit train (in lane 2 that the player is in) then ploughs into the iron train that is stopped in the junction (the breaking zone looks ok for this train).

I was able to get in one the the trains and save it again around 5 second before the collision (attached). I have another save around 20 seconds before as well if it needed.

Thanks

G

Thanks for the perfect safe where I could reproduce the problem again and again while debugging.
I reorganized and cleaned up parts of the train logic to avoid weird inconsistencies like this that could happen (I'm surprised that this was not happening much more often).

This problem is fixed, but as it required some bigger changes, it is fixed for the 0.16 version.