Would this possibly be using a railgun to initiate takeoff speed (reducing fuel a lot) and then some for a plane that then obtains very high speed in very high orbits to then be able to land and use existing airports.
This is only logical given the prospect to use a railgun type launcher to eliminate booster rockets or reduce fuel for space flight. So would marry in with other avenues of research and as such be less of a risk and Musk don't like risk.
This at least would fit the criteria, maybe with the initial speed a form of electric powered plane, maybe Musk and Dyson could get together and invent a good electric jet engine (yes probably be ion based but still).
This is only logical given the prospect to use a railgun type launcher to eliminate booster rockets or reduce fuel for space flight. So would marry in with other avenues of research and as such be less of a risk and Musk don't like risk.
This at least would fit the criteria, maybe with the initial speed a form of electric powered plane, maybe Musk and Dyson could get together and invent a good electric jet engine (yes probably be ion based but still).