If you really want to get a LOT of mass to orbit cheaply, it's probably
better to do it with a larger than a smaller rocket, just to reduce the
total number of launches required. I calculated the other day that we
could deliver 300,000 tons to equatorial LEO with four flights per day
of Starship/Superheavy. That's about the same annual cost as SLS (~$20/lbm).
On 10/3/21 14:45, John Schilling 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] *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/ <https://urldefense.com/v3/__http://www.cesaronitech.com/__;!!LIr3w8kk_Xxm!5kYs525JE3jfChOKTniySYrfhBtw7Q2Vsxr4OVzpi--OukATDnyEJiB-PJj8bdfowA98qI3w_g$>
(941) 360-3100 x1004 Sarasota
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*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
>