You also need something that can transfer the thrust to the payload. If you’re burning this thing as an SSTO, it needs to survive being shoved forward at rather more than 1g with payload attached, presumably at the end opposite the nozzle.
I suppose one could attempt a truly exotic design in which the fuel tank gets gasified, piped past the payload, and then burned, thus allowing the tank to be on top, but these seems unlikely to work very well.
>I suppose one could attempt a truly exotic design in which the fuel tank gets gasified, piped past the payload, and then burned, thus allowing the tank to be on top, but these seems unlikely to work very well.
I've been thinking of this design for a long time, but so far it sounds a bit preposterous even for a sci-fi enthusiast with no rocketry knowledge :)
I suppose one could attempt a truly exotic design in which the fuel tank gets gasified, piped past the payload, and then burned, thus allowing the tank to be on top, but these seems unlikely to work very well.