I got past mission 5 yesterday, with energy to spare, so it's doable. I had been practicing optimizing my lift-offs, so probably that helped a lot... It makes more sense to add batteries, I could'n figure out why the kerbal space agency would want to put a probe up there that has no power to do anything after it just arrived I really like the mission pack, as it adds purpose to the game. This has been missing for a while now, I'm really looking forward to career mode. Your mission pack is what made me start playing again, so thanks!