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.

Sylvia.