I really like having heat as a problem to deal with, bu I don't like *something* about the new thermal system. I'm just not exactly certain what it is. I do know that with pre-stock DRE I could do things like put delicate parts on the backsides of SSTOs so they didn't blow up on re-entry, and now that doesn't work at all... my airbrakes and fuel cells always burn up if they're connected to an empty tank (but don't if they're connected to a full tank!). Ships seem to randomly gain and lose heat with warp, sometimes explode for no reason, and none of the supposed heat-reducing parts do much of anything. Speaking of heat-reducing parts, today I deleted KSP, then reinstalled from Steam. Then I started a sandbox, created a ship consisting of a single 2.5m probe core, a mk3 liquid fuel tank, 12x Radial Attachment Points, 12x LVN engines, and 8 launch clamps. Then I launched the craft and turned on debug thermal info. Picture of testbed: http://i.imgur.com/mUYwmLu.png After firing the engines to exhaustion on the pad 3 times for each config (remaining clamped to the ground), I got the following as the avg peak temp of the fuel tank after 3 runs attaching various heat-reducing parts to the tank: 545.3 - No thermal additions 536.0 - 8 large radiators 508.5 - 8 medium thermal control system panels (deployed) 540.0 - 8 medium thermal panels (undeployed) 504.3 - 8 large thermal control system panels (deployed) 525.3 - 8 large thermal control panels (undeployed) 426.1 - 1x additional mk3 fuel tank (fuel locked) In all cases, the engines (obviously the hottest part) peaked within a few tenths of a degree of 560. This isn't a perfect test, I know, and there's a lot more that I could do to investigate further (vacuum vs air, larger vs smaller mass, longer time, etc), but I think this does show that radiators are useless, you need a stupid amount of TCS to even make a small dent in heat, and if you really want to survive a high heat environment you're better off increasing your thermal mass instead of adding any of your current options for cooling. Even worse, NONE of the above changed the heat of the engines themselves... we've got NO option to try and control engine heat? Anecdotally, as I mentioned before, I know that my spaceplanes survival rates are MUCH better when they re-enter with full tanks. Summary and TL;DR - I enjoy the game and like having heat as a problem, but I want more/better options to deal with it, because the current options aren't very good.