Thanks for your answer. You are right. I am playing with terrain scattering and full texture resolution. I will look through the error.log file as soon I am back from work. If I find anything memory related I will use lower settings. Thanks! EDIT: I found this on the beginning of the error.log: Unity Player [version: Unity 4.6.4f1_99f88340878d] mono.dll caused an Access Violation (0xc0000005) in module mono.dll at 0023:1011940a. Error occurred at 2015-09-14_182908. C:\Program Files (x86)\Steam\steamapps\common\Kerbal Space Program\KSP.exe, run by [...]. 60% memory in use. 0 MB physical memory [3209 MB free]. 0 MB paging file [0 MB free]. 0 MB user address space [104 MB free]. Write to location 00800000 caused an access violation. This looks memory related (at least for me). I lowered the texture resolution and disabled terrain scattering, and the game did not crashed after playing ~1,5 hours. Thank you kerbanoid! If a mod is reading this: Is there a way to mark this post as resolved?