I’m broadly inclined to agree w/ George.
A finer analysis starts w/ where’s the market? I’ll just assert that the
GEO Comsat business doesn’t wash: it’s always cheaper to use the existing
system; I promise that is a carefully reached conclusion and I’d be happy
to repeat that analysis for anyone who can stomach my fee.
There is a variant analysis that considers a builder of small GEO’s that
also has a launch vehicle(...), in that case a depot that allows the
existing LV to launch the existing small Comsat to a depot that refuels the
upper stage so that the Comsat can be placed directly in GEO (thus saving
the cost of the insertion motor) doesn’t make any sense at all. But it
makes more sense than alternatives and may suggest that it will require
both a spacecraft manufacturer and a launch vehicle manufacturer working
together to create a depot based architecture...which probably won’t
compete w/ existing systems.
Next up would be tourism. If the on-orbit B&B’s are at 28 degrees then...a
depot isn’t needed. Which reveals that depot’s only make sense for beyond
LEO missions. A trivial but useful understanding.
But an understanding that means that a depot will only make sense—if
ever—in a far future where there is heavy traffic w/i the Earth-moon system.
Bill
On Sun, Aug 25, 2019 at 5:17 PM George Herbert <george.herbert@xxxxxxxxx>
wrote:
For a US depot, it’s most likely launched from the Cape, and 28 ends up
being approximately optimal.
-george
Sent from my iPhone
On Aug 25, 2019, at 3:53 PM, Norman Yarvin <yarvin@xxxxxxxxxxxx> wrote:
As regards fuel depots in LEO, what orbit do people conceive them as
being in? Equatorial orbit, so that they can service launches heading
to GEO and beyond? Something like the Space Shuttle's usual orbit, so
that launches from Florida can reach them without a plane change? Or
what?
