Why is a SSTO not useful today? My chief complaint is that it is because ever sinse beginning folks have though of a SSTO as using one single chemical rocket burn from start to finish and this simple is not very effiecnt at all. My idea is with the SSME like 25 years ago SSTO started to be feasable when you look at most effient three dimensional solution I am presently suggesting. I have done the figures and came up with a one million GLOW rocket seven percent empty bit over three percent useable payload thrust weight ratio 1.5/1 and nearly 10 kilometer/second burn out velocity too. Thanks