Will, it's about time I shared my rockets. All of these are stock parts only, and I can establish orbit with any one of them. The Orbiter Mk 1. A fairly reliable ship, if a little finicky to get into orbit. :-\ The Orbiter Mk 1 Mod 1. Slightly more tankage gives a somewhat higher chance of successful orbiting. The Orbiter Mk 2. Switching to liquid fuel and adding a few solids to get it off the pad leave it FAR more reliable in terms of 'reaching orbit', but something of a thrillride in the upper atmosphere. ??? And, the Orbiter Mk 2 Mod 1. This thing goes exoatmospheric before first stage burnout. I eventually got bored with waiting for it to stop climbing, gave it a retro burn, and circularised the orbit... roughly 6000km up. The Mk 2 is... abusive towards my PC. This is a beast of a machine, and it takes until well after all the solids are gone for the framerate to get out of single digits. Jebediah LOVES it! 8)