Wow guys, thanks for all the advice! There's so many helpful people here, obviously I can't reply properly to you all. Thanks for the nice welcome. I have read all your posts and been trying various changes. I've not had the sucess I was originally after but that's possibly because I was aiming too high The SRBs were just so I could turn my ship easier in space, as previously I could barely shift my ships rotation due to its size. I managed to get a rocket into orbit by staging my fuel differently, however each fuel tank had an engine and I was out of fuel once I actually reached space. So after reading some of your posts, I'm going to aim for a more central thrust supplied by various stages of fuel so I an jettison the dead weight. The main problem I have now is once I'm in space, what design should I have? Will I have decoupled the old larger thruster for a smaller design? I tried that but ran out of fuel whilst stabilising the orbit.