Hey everybody! I've been playing KSP since .19, but this is my first time on the forum! I thought I would share some of my recent SSTO designs with you! I put these under Mod Craft Because they have MechJeb installed on them but everything else is just the new stock parts from .25. This first one is the Delta Flyer Mrk III (first two were not that great). I wanted to make an SSTO that could go to Laythe on it's own power. I have a good network of space stations set up in the solar system at this point (one at the Mun, Eve, and Dres), and a great tug design that I really like, but because of the docking port not being at the center of mass on this design I could not push it to Laythe very simply. So I designed engine modules that are self contained and can dock (usually via MechJeb) with the engine ports on the back. This design can reach orbit around Kerbin under its own power, shed two of its R.A.P.I.E.R engines and replace them with atomic ones. After refueling it can then make the trip to Laythe. The tug can then bring the R.A.P.I.E.R modules along with extra fuel and the whole thing can then serve as a Laythe transport to and from the surface (planning to create another station there soon for exploring Jool's moons). From Kerbin's surface it can reach a decent orbit of about 100 km with a couple hundred delta-v to spare, and can do even better on Laythe. Here are some shots of the process. After that I really wanted to see if I could make a design that could take more kerbal's to and from the surface (via the new 4 seater crew module). I also wanted to make it smaller and lighter so the tug could pull it to Laythe. So I made the Mrk IV. I ditched the swappable engines and removed some of the fuel. This design proved to be pretty great (a tad harder to land because of less lift). The cut down weight actually made it able to reach orbit around Kerbin and Laythe with similar leftover delta-v to the Mrk III (about 400m/s at Laythe). This design was actually light enough where my tug could take two of them to Laythe with fuel to spare. So there ya go my first successful SSTO designs! Hope you guys enjoy them! If you would like the craft files or anything just lemme know!