SpaceX Aims For 2009 Re-usability Demo

See:

http://www.aviationweek.com/aw/gener...&channel=space

I hope it goes well.

wrote in message
...
See:

http://www.aviationweek.com/aw/gener...&channel=space

I hope it goes well.

I wonder if their launch prices take reusability into account.

wrote:
See:

http://www.aviationweek.com/aw/gener...&channel=space

I hope it goes well.


They will have a hell of a time figuring out how to get that second
stage back down in one piece.

Pat

Pat

On Jan 10, 11:19*am, Pat Flannery wrote:
wrote:
See:

http://www.aviationweek.com/aw/gener...ws/STAGE010909.....

I hope it goes well.

They will have a hell of a time figuring out how to get that second
stage back down in one piece.

Pat

Pat

Would a winged booster (or boosters) would make more sense
than a winged orbiter like the Shuttle? I know various flyback
booster schemes have been proposed over the years. But
would that be economically preferable to parachuting a non-
winged booster into the ocean for recovery via boat?

wrote:

Would a winged booster (or boosters) would make more sense
than a winged orbiter like the Shuttle? I know various flyback
booster schemes have been proposed over the years. But
would that be economically preferable to parachuting a non-
winged booster into the ocean for recovery via boat?

Depends on your definition of 'economically'.

D.
--
Touch-twice life. Eat. Drink. Laugh.

http://derekl1963.livejournal.com/

-Resolved: To be more temperate in my postings.
Oct 5th, 2004 JDL

Pat Flannery writes:

wrote:
See:

http://www.aviationweek.com/aw/gener...&channel=space

I hope it goes well.


They will have a hell of a time figuring out how to get that second
stage back down in one piece.

This would be a good point to finally try active cooling. Let the fuel
tank heat up and design in pressure-controlled valves that vent residual
(vaporized) fuel over the skin of the stage, cooling it and protecting
it from the plasma. I have always thought that this is the best way to
get anything mainly consisting of large and nearly empty fuel tanks
intact through reentry.


Jochem

--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery

wrote in message
...
See:

http://www.aviationweek.com/aw/gener...&channel=space

I hope it goes well.

Me too. They're taking baby steps on each flight. In the long run, I think
they've got a chance to change the way the US launch industry operates, but
it won't happen all at once.

Jeff
--
"Many things that were acceptable in 1958 are no longer acceptable today.
My own standards have changed too." -- Freeman Dyson

wrote:
Would a winged booster (or boosters) would make more sense
than a winged orbiter like the Shuttle? I know various flyback
booster schemes have been proposed over the years. But
would that be economically preferable to parachuting a non-
winged booster into the ocean for recovery via boat?


If you are going to try to use flyback boosters, this is about the only
design for one I ever saw that looked like it would make sense:
http://www.buran.ru/htm/strbaik.htm
http://www.mati.ru/english/index.php?path=science/fsp
It's the "Baikal" booster design.
The top-mounted wing swings 90 degrees to lie along the side of the body
during ascent, then opens after its fuel is expended to let it glide
back down; propulsion is provided by the nose-mounted jet engine(s) as
it flies back to the launch site to land like a conventional airplane.
The downside is that it looks like a winged erect penis, but that will
show the manliness of the boosters using it. :-)

Pat

Jochem Huhmann wrote:
This would be a good point to finally try active cooling. Let the fuel
tank heat up and design in pressure-controlled valves that vent residual
(vaporized) fuel over the skin of the stage, cooling it and protecting
it from the plasma. I have always thought that this is the best way to
get anything mainly consisting of large and nearly empty fuel tanks
intact through reentry.


But you are going to have to keep it stable as far as orientation goes
during reentry, and that's probably going to mean spinning it up so a
nose-mounted heatshield/active cooling system stays pointy-end first as
it comes in...given it's shape that may not be easy.
Since the only expensive things on it are the guidance electronics and
engine, it might be smarter to mount the electronics back at the tail
end of the stage near the engine, and just have that section come down
via parachute while the propellant tankage is allowed to burn up. That
would certainly save a lot of weight on the parachute system.

Pat

Pat Flannery writes:

Jochem Huhmann wrote:
This would be a good point to finally try active cooling. Let the fuel
tank heat up and design in pressure-controlled valves that vent residual
(vaporized) fuel over the skin of the stage, cooling it and protecting
it from the plasma. I have always thought that this is the best way to
get anything mainly consisting of large and nearly empty fuel tanks
intact through reentry.


But you are going to have to keep it stable as far as orientation goes
during reentry, and that's probably going to mean spinning it up so a
nose-mounted heatshield/active cooling system stays pointy-end first as
it comes in...given it's shape that may not be easy.

Pointy-end first seems like a bad idea (and should be almost impossible
since the heavy end is at the engine).

Since the only expensive things on it are the guidance electronics and
engine, it might be smarter to mount the electronics back at the tail
end of the stage near the engine, and just have that section come down
via parachute while the propellant tankage is allowed to burn up. That
would certainly save a lot of weight on the parachute system.

This would mean having a clean separation point between tail and tankage
and a real heat shield... You would need to build the thing totally
different then. While I agree that the tanks are actually quite
worthless, using them to brake high and early and to have a large area
to spread reentry heat over makes more sense.

Anyway, I think recovering the second stage with its single engine isn't
really worth the trouble. Recovering the first stage with its 9 engines
is both more useful and easier. And even then it would be wise to
have it fly back and land instead of dropping it into seawater and
recovering it there.


Jochem

--
"A designer knows he has arrived at perfection not when there is no
longer anything to add, but when there is no longer anything to take away."
- Antoine de Saint-Exupery