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A comment on SpaceX Launches Super-Heavy Communications Satellite. Parent comment

Re:SpaceX Launches Super-Heavy Communications Satellite by ChuckMcM on Tuesday May 16, 2017 @12:15AM (#14347316)
Elon's tweet today (https://twitter.com/elonmusk/status/669132749500887040) was that a booster with no payload could put itself into orbit. And that certainly supports your statement. It clearly would not be possible to launch a second stage and have the booster stage make it all the way into orbit. But it isn't as far out of whack as it might be.
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Re:SpaceX Launches Super-Heavy Communications Satellite by wolf550e on Tuesday May 16, 2017 @01:44AM (#14347623)
Tsiolkovsky is very clear about the propellant mass fraction needed for single stage to orbit, and it is unachievable with current materials, i.e. you can't build a useful SSTO using Al-Li tanks.

https://en.wikipedia.org/wiki/Single-stage-to-orbit#Design_c...

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Re:SpaceX Launches Super-Heavy Communications Satellite by Symmetry on Tuesday May 16, 2017 @08:49AM (#14349115)
The first stage has a fuel mass fraction of 95.5%. Propellant densification and high thrust to weight ratio engines buy you lot. That should be enough to make orbit.
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Re:SpaceX Launches Super-Heavy Communications Satellite by marvin on Tuesday May 16, 2017 @03:21AM (#14347927)
SSTO with a significant payload then, presumably.
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Re:SpaceX Launches Super-Heavy Communications Satellite by xorxornop on Tuesday May 16, 2017 @03:25AM (#14347947)
Yup. Even carbon composites don't really work out (minimal payload) until the rocket is very large (see: ITS)
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