I made another LF-only SSTO spaceplane! It can now dock and deliver small cargo!
I like the five ramjets with low and high altitude scoops. But just nuclear engines for space propulsion? Obviously that's enough to get from the top of the atmosphere into orbit, but is there a trick to your approach angle or something? It looks like you were going almost vertical at that stage, but I would have thought you'd be maintaining shallow flight as long as possible to build up lateral speed.
With LV-N's, the trick is actually
altitude. No matter how you slice it, you can't exit the atmosphere on turbojets going faster than 1300m/s, and you can't use turbojets above some 22km. So what you do on ascent, is buy yourself time to accelerate using the Nervas' very low thrust.
My ascent profile looks like this:
From runway, fire turbojets at half throttle. Take off and pitch up 40 degrees.
Maintain half throttle until about 4-5km. Punch it to full throttle to begin accelerating. Maintain pitch.
At 10km, stage to fire NERVAs. They're almost fully efficient at that altitude and every little bit helps. Adjust pitch to 45 degrees.
Keep going until your turbojets run out of air, then turn them off and close all intakes. With a properly built design you'll be flying at at least 1200m/s. Keep full throttle on the NERVAs.
Adjust pitch to be slightly above your prograde vector. Once you clear the bulk of the atmosphere at some 45km, adjust pitch to be halfway between your prograde, and your trajectory normal vector.
Keep adjusting your pitch to be somewhere between the prograde and the normal as you reach apoapsis. You'll reach some 120-125km, still going at about 1200-1300m/s.
Continue doing this as you start losing altitude. If everything goes right, you will eventually circularize at some 90km.
This is a
very inefficient ascent profile. With any other setup, you would never want to use it. However, you can't have many LV-Ns due to overheat, and you are stuck carrying a lot of dead weight in turbojets, so an
efficient ascent profile doesn't leave you enough
time to make orbit, and you aren't carrying any oxidizer, by design, to boost you up with conventional rockets.