Sylvia Else wrote:
kT wrote:

Sylvia Else wrote:

It's all about the overall cost of putting payload into orbit. A TSTO
would presumably give a better payload ratio, but with extra
complexity (equals dollars) both in the vehicles themselves, and in
handling the vehicles when they're in use. So the net cost per kg in
orbit may be higher for a TSTO than for an SSTO despite the higher
payload ratio.

An airliner style operation using a single vehicle per mission is
very attractive if it's achievable. After the vehicle lands, you just
refuel it, put in the next mission's payload and you're ready to
launch again.


And I posit we must approach that SSTO RLV launch scenario
incrementally. The 100/10/1 puts the masses involved in perspective.

However, one can argue that the expendable SSTO approach puts almost
an order of magnitude more mass into orbit, which is what I am
suggesting.


Only because you're deeming that the spacecraft hardware in orbit is
part of the payload. That's fine if you have someone who wants that
payload in orbit, but most launches involve other kinds of payload.

Then they can launch on little Dneprs for all I care, I want to colonize
space, and the 100/10/1 rule is the only way I know how. If I'm going to
be flying around in a large spaceship for any length of time, I want as
much fuel and hardware as I can get. By leveraging the 10/1 rule to our
advantage the material and infrastructure in orbit gets large very fast.

Plus, I can get the engines back, so it's sustainable, and it's an order
of magnitude less flights that it otherwise would have taken. Thus, it's
scalable and sustainable so things only get bigger and better over time.

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