I have some static meshes that drop to the ground. When I start the game or simulate some of them will fall through the ground and some don’t sometimes none of them fall through the ground. However if I let them fall onto another static mesh they do not fall through at all. Here is a video demonstrating the problem.
You can turn on Continuous Collision Detection (CCD) for them.
Thank you, that solved my problem.
Should post as answer so we can give you props