John:
This is similar to the argument that ELV’s could compete w/ RLV’s if they
could be produced and fly thousands of time per year. And I agree that the
very limited data doesn’t prove which is most correct.
But first mover’s have a real advantage: if ELV’s had manically pursued
low cost—something that your employer notably acted to oppose—than that
might be the path things ran down. But that is over: SpaceX dropped ELV
prices by a factor of four and then built a partial RLV that prices at
about one-third of ELV prices, RLV’s are now the canonical solution.
If SpaceX gets a BFR working then there will not be a space in the market
for twenty tons at six or eight times as many launches: first mover likely
wins for the next few decades, not least because payloads will get sized
for that vehicle.
Assuming no world war.
Bill
On Sun, Oct 3, 2021 at 3:45 PM John Schilling <john.schilling@xxxxxxxxxxxxxx>
wrote:
Mars only requires a BFR if you insist on flying to the surface of Mars in
a spaceship you launched from the surface of Earth. Which, admittedly, is
what Apollo and fifty years of science fiction have programmed people to
expect. But if you are willing to use on-orbit assembly, and if you're
planning to go to Mars a *lot* you really ought to, then what matters is
large *total* launch capacity at low cost per ton, and no need for any
single launch to be >20 tons.
Whether a few larger launches or many smaller ones gets you lower overall
cost per ton is uncertain, but the effect is probably not large. There are
economies of scale for larger launch vehicles, but there are also economies
of scale for higher flight rates, and they very roughly cancel. So no, you
don't need either a BFR or new physics to go to Mars.
If you want to pay for your trip to Mars in part by selling launch
services to customers whose interests lie closer to home, it is probably
advantageous to offer flights on demand on a rocket scaled to the LEO and
GEO markets.
John Schilling
On 9/30/2021 5:15 PM, Troy Prideaux wrote:
From my (albeit naïve) understanding, Elon’s driving goal has always been
Mars – which ultimately requires (in the absence of new physics) a BFR.
Troy
*From:* arocket-bounce@xxxxxxxxxxxxx [mailto:arocket-bounce@xxxxxxxxxxxxx
<arocket-bounce@xxxxxxxxxxxxx>] *On Behalf Of *Anthony Cesaroni
*Sent:* Friday, 1 October 2021 10:10 AM
*To:* arocket@xxxxxxxxxxxxx
*Subject:* [AR] Re: Nothing to do with rockets.
Hi Bill,
One could argue that the plateau was reached with the 747 and finally the
A-380. Operational costs and the overestimate of the hub model in the case
of the latter. The 777 appears to be able to sustain the “jumbo” mission
and operational cost models currently as I understand it. That said, I’m
not sure that it’s apples to apples when it comes to comparing any of this
to spacecraft. Elon certainly believes bigger is better and it will be
required for his mission goals.
Best.
Anthony J. Cesaroni
President/CEO
Cesaroni Technology/Cesaroni Aerospace
http://www.cesaronitech.com/
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(941) 360-3100 x1004 Sarasota
(905) 887-2370 x222 Toronto
*From:* arocket-bounce@xxxxxxxxxxxxx <arocket-bounce@xxxxxxxxxxxxx> *On
Behalf Of *William Claybaugh
*Sent:* Thursday, September 30, 2021 7:53 PM
*To:* arocket@xxxxxxxxxxxxx
*Subject:* [AR] Re: Nothing to do with rockets.
Rand:
Just like the airlines.
Bill