If I did the quick math right (no promises) as an expendable SSTO with
mission Isp 340s, GLOW 247.6 MT (T:W 1.264 like F9), 9.5 km/s:
0000 kg payload at stage MR 17.3
2050 kg payload at stage MR 20
4600 kg payload at stage MR 25
6300 kg payload at stage MR 30
30 is what they claimed for the Falcon Heavy boosters. Obviously
harder to accomplish with LOX/CH4 than LOX/RP1.
So as an SSTO it's still significantly more capable than a Falcon 1.
I don't see any use in SpaceX actually building such a rocket. Might
be a market for someone else to build one, but the shape of the
overall launch market with a company having cheap heavy lift on tap is
a very different market than the thing we're pretending is a market
that we're in now.
On Sun, Oct 2, 2016 at 10:38 AM, Ben Brockert <wikkit@xxxxxxxxx> wrote:
It wouldn't be a small rocket at all. It would have similar payload
capacity to the Atlas V if they had a high performance upper stage to
put on it and a better overall mass ratio.
The Raptor is a big engine. The smallest thing you could reasonably do
with it is use it as an upper stage engine for the Falcon Heavy with
an overweight upper stage to help push down the staging altitudes.
On Sun, Oct 2, 2016 at 10:28 AM, Dave Täht <dave@xxxxxxxx> wrote:
I am curious as to how a falcon-1 style version of the design would
would compare to an updated falcon 1e design using all the new sexy stuff:
Methane v RP-1
The benefit of supercooling?
composite v aluminum?
Raptor v Merlin 1D?
... In terms of potential payload to LEO.
Despite the excitement behind the BFR, it strikes me that following the
sane design path for building it would be the simpler strategy of
starting small, and for all I know there's still room in the world for a
small launcher with better performance than the 1 had.
