[Spaceships] getting into orbit without superscience?

[Prince Charon]

Space elevators are tricky to build and potentially dangerous if things go wrong, but do seem to be possible, and might end up being an efficient solution to the issue of getting into orbit, compared to rockets. There are also a few other methods of non-rocket spacelaunch that might work.

Atomic Rockets has a fairly long list of realistic Surface to Orbit concepts, both rocket (not limited to atomics) and otherwise.