In article ,
says...

"Jeff Findley" wrote in message
...
**** Elon Says (transcripts)
http://****elonsays.com/transcript

There are some interesting nuggets of information in the September 29
2013 transcript.

An amusing site to maintain an archive of Elon's musings, but what do you
think are the most interesting statements in this last press conference?

I found all the info on reusability of the first stage(s) interesting.
For example:

[Question on performance hit for attempting landing the first stage]
We effectively lose, in terms of performance... It really depends on
what we want to do with the stage if we were to do an ocean landing
or a return to launch site landing. If we do an ocean landing, the
performance hit is actually quite small at maybe in the order of
15%. If we do a return to launch site landing, it's probably double
that, it's more like a 30% hit (i.e., 30% of payload lost).

[Question on the recovery of the first stage during CRS flights]
Our goal is to recover the first stage on all CRS flights and
really on most flights. The next two flights are somewhat of an
exception. When we negotiated these deals, we didn't have much
bargaining power. It was before we obviously flown this version
of the Falcon 9 successfully. So we kind of agreed to give up
all performance on the rocket and not reserve anything for
reusability. But going into the future, with future contracts,
with a few exceptions, we have reserved enough performance to
recover the stage. It's not just the CRS flights, it should be
most flights after these next two (flights). In terms when we
actually re-fly the stage, it's going to depend on what
condition the stage is in and obviously getting customers
comfortable with that. So it's difficult to say when would
actually re-fly it. If things go super well then we would be
able to re-fly a Falcon 9 stage before the end of next year
and that's our aspiration.

[Question on the impact of this version of Falcon 9 on the
Falcon Heavy] It (i.e. the Falcon 9 version 1.1) definitely
informs the Heavy development. The Falcon Heavy is essentially
the Falcon 9 with two additional boost stages as strap on
boosters. So it's the same engines that we use, very similar
airframe, the airframe will be slightly optimized because of
the fact that it is a side booster but the avionics will be
the same as the Falcon 9 first stage. How we control the whole
thing will be very very similar. Hopefully, once the three
boost stages separate, they will come back and land
individually and they will behave just like the Falcon 9 boost
stage. All three of them will come back hopefully and land on
three separate pads and we'll join them back together for a
future flight and launch them.

Jeff
--
"the perennial claim that hypersonic airbreathing propulsion would
magically make space launch cheaper is nonsense -- LOX is much cheaper
than advanced airbreathing engines, and so are the tanks to put it in
and the extra thrust to carry it." - Henry Spencer