I updated to the newest version, but I'm still getting the same results. Once my ET was drained, I had approximately 400 meters of acceleration to go in a 110x150 km orbit. My OMS was giving me less than 1/ms, and the estimated remaining burn time was over 5 minutes long. By that time, I'd be reentering the atmosphere! If it's of significance, my payload is approximately 8.5 tons. I don't wish to make you do something just for me, but instead of tweaking fuel consumption, could you make a patch to make the engines more powerful in vacuum, in case people (like myself) have trouble with the newer engines? While I'm at it, I'd like to say your work is fantastic. I absolutely can't wait till everything is finished so I can build Space Station Freedom.