I'm noticing an instant ~200m/s acceleration on every vessel when transitioning from space to atmosphere (70km) on Kerbin. Making reentry impossible for my early career craft. It's a mod heavy install, but a quick removal of Principia makes the problem go away and a reinstall makes it reappear. Later I'll try it on a fresh install of KSP and report back.
Fresh install fixed the problem, now to reinstall mods one by one to find the culprit.
It appears to happen randomly and with different mods installed (tested all night!). Running Tasker and Resource Monitor on my second monitor shows no abnormal CPU loads or memory issues. Heck, on my last attempt fully modded it didn't even do the acceleration. I'll try to learn how to pull logs and see if those shed any light on whats going on. If anyone else is experiencing this, please chime in!