Okay I just found one on Baidu Tieba (Chinese website...) The owner just posted a picture of it reaching orbit. (Translated Chinese into English) I made one as same as his(Mass=1.265t, dV=5372m/s, TWR=2.42) then a lighter one(mass=0.703t, dv=4275m/s, twr=4.35) Enough to reach orbit! ..... so that's all. Moderator Comment: Your links were broken. I removed them so you could fix if desired. Welcome to the forums! ~Claw