I'm having the same problem as Blackbeard, and posting log and craft data. https://www.dropbox.com/s/yexwxcrjgt6ddse/KSP.log?dl=0 https://www.dropbox.com/s/6vnm2ae680gl3ik/Untitled%20Space%20Craft.craft?dl=0 It happens after I get into orbit and try to re-focus. Long as I know it is a problem only with Ion engines. Ships with other KSPI parts loads perfectly. Even if you only change the engine to any non-Ion engine, it loads normally. Hope the data helps. Sorry for my poor English. P.S. AluminiumHybrid engine's node definitions seems to be wrong. Changing node_stack_bottom = 0.0, -12.5127, 0.0, 0.0, 1.0, 0.0, 2 to node_stack_bottom = 0.0, -12.5127, 0.0, 0.0, -1.0, 0.0, 2 and node_stack_top = 0.0, 10.2547, 0.0, 0.0, -1.0, 0.0, 2 to node_stack_top = 0.0, 10.2547, 0.0, 0.0, 1.0, 0.0, 2 lets you attach another engine underneath and a nosecone on top.