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I dug through the forums and couldn't find anything quite like this. It promises to be a pretty kerbal sort of challenge, so hopefully we will get some interesting entries. Building an SSTO seems to be pretty popular for early players. Airbreathing spaceplanes are the most common, though pure-rocket and VTOL SSTOs are typical too. Building a reusable SSTO in Demo Mode, on the other hand...that's a bit of a challenge. It's easy enough to stack stages in Demo to achieve pretty much anything you want, but with only a single liquid-fueled engine, what you can do in a single stage is limited. The LV-T30 (at least, the one in the Demo) has a sea level TWR of 14.8, which isn't exactly ideal for an SSTO. With an ISP maxing out at 305 s and the demo's maximum tankage ratio of 9:1, the theoretical maximum delta-v of an LV-T30-based SSTO is 5.47 km/s with a launch TWR of exactly 1:1. This is more than enough to reach orbit, of course, but when you factor in decreased atmospheric specific impulse, aerodynamic drag, a reasonable launch TWR, and a host of other considerations, you end up cutting it pretty close. And getting back down to the atmosphere, surviving re-entry without heat shields, and still having enough fuel to land without parachutes...that's tough. So that's the challenge! Build a single-stage rocket using only Demo parts that can take off, reach a stable orbit, re-enter, and land propulsively without a parachute. A list of demo parts is available here. However, this list includes the TVR-1180C Mk1 Stack Tri-Coupler, the AV-R8 Winglet, and the Telus Mobility Enhancer, none of which are present in the demo I have, so they aren't allowed for the purposes of this challenge. Anything else on that list is fine. To qualify as a single-stage rocket, the entire rocket (minus launch clamps) must reach orbit and return to land without any loss of parts. A stable orbit is an orbit greater than 70x70 km. Water landings are permitted as long as you touch down under rocket propulsion and no parts break. No autopilot mods, but anything else is fine. Control is going to be a challenge; without a vectorable engine or control surfaces (and minimal mass budget for reaction wheels or RCS), a lot is going to depend on aerodynamics and your center of mass. For that reason, some part clipping is fine. Scoring of qualified entries is based on extra points, available as follows: Playing in the actual demo: +200 points Reaching an orbit of at least 100x100 km: +500 points Retrograde orbit rather than prograde orbit: +300 points Using a single re-entry rather than multiple aerobraking passes: +100 points Landing on the daylight side of Kerbin: +50 points Landing on land rather than on water: +75 points Landing in sight of the VAB: +200 points Landing on the actual launch pad: +100 points Landing on deployed landing legs: +25 points Ties will be decided by whichever entry has a lower launch mass. Good luck to all!