Commercial spaceflight & then what?

Wouldn't you have to build the orbital depot first?

True. Now, if NASA was to build it, they would probably charge a few
billion to build and launch it. Then they would charge the tax payer
billions to run it, and if anyone other than NASA wanted to use it,
then they would need to qualify, then fill the paperwork, and get NASA
approval.
OR if you simply wanted orbital depot instead of a jobs program for a
orbital depot. The govt can simply pay for fuel to be delivered to
some place in orbit, then once enough fuel was placed in orbit, the
govt could simply offer to give the fuel to any party which will build
and operate this orbital depot. So instead of govt designing and
building something, the govt can merely subsidize the project by
buying payloads of fuel to be delivered to orbit. Beside providing a
place to fill up for NASA or other parties, the operator can find
other benefits, such as location for tourists or many other commerical
activities.

If nothing else, you'd need somewhere to house those assembling the lunar
mission's ship. As a benchmark, the ISS will be over 350 metric tons when
finished. Even if your depot was only one-tenth it's size, that would
still be a lot of missions to fly (at 2000 lbs apiece) before you could
even begin flying the missions to take the pieces of the lunar ship into
orbit. Not to mention the missions for rotating crews while the lunar ship
is being constructed.

So, let's try it with existing stuff. Take Sea Launch, they are
probably now charging around 80 million per launch to GTO. Since we
are buying in volume, we want a modest discount (might get
considerably less but why argue about it) let's say the govt offers 70
million per 5 tons delivered to a GTO type orbit. So are paying about
$7,000 per lb- if this was instead going LEO we get double the
payload- get better than $3,500 lb. Now Sea Launch can take it or
leave it, but they would be crazy not to take it. The main problem
will be all the crying about how unfair this is [and it is unfair,
govt is paying far too much, and Sea Launch would get rich from it].
Anyways, say govt buys 10 launches- 700 million, about the cost of
launching one Shuttle. Giving 50 tons of fuel in a GTO type orbit. Now
this orbit is going through the Van Allen belts, but you will have
about 50 cu meters of sheilding in the form of this fuel, so the 10
payloads could arranged to block most of the radiation affects from
belts or solar flares- whoever is making the fuel depot might want to
use this as part of design. So Govt spends the 700 million on payloads
then give these payloads to anyone who will invest capital need to
turn this into a place in which spacecraft can refuel. Govt cost: 700
million. Private sector cost: variable.
The funny thing about this is that some people are probably going to
have two inflicting thoughts bashing about in their skull. First is
this 50 tons of fuel payloads would be "worthless" and the other
thought will be "who gets to have it". I would simply say that
ignorance and greed are evils that people should deal with

In article ,
h (Rand Simberg) wrote:

On Sun, 10 Aug 2003 19:02:53 +1000, in a place far, far away,
(Stephen Souter) made the phosphor on my
monitor glow in such a way as to indicate that:


$1000 x 2000lbs == $2,000,000 per launch. That sounds too good to be true!

Not to me, as long as you do enough launches.

So, each of those 30 missions, you fill up your orbital depot and sell to
the highest bidder.

Wouldn't you have to build the orbital depot first?

If nothing else, you'd need somewhere to house those assembling the lunar
mission's ship. As a benchmark, the ISS will be over 350 metric tons when
finished.

ISS is a lousy benchmark for an orbital propellant depot.

Then what would you use as your benchmark?

In the example I was responding to the launcher being used was limited to
a payload of 2000 lbs.

--
Stephen Souter

http://www.edfac.usyd.edu.au/staff/souters/

On Mon, 11 Aug 2003 12:07:07 +1000, in a place far, far away,
(Stephen Souter) made the phosphor on my
monitor glow in such a way as to indicate that:

ISS is a lousy benchmark for an orbital propellant depot.

Then what would you use as your benchmark?

I would use the design of a system whose purpose was to be an orbital
propellant depot, designed by people whose interest was in building
that, rather than padding payrolls in Houston, Huntsville and Florida,
and providing appropriate kickbacks to certain people in the nation's
capital.

--
simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole)
interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org

"Extraordinary launch vehicles require extraordinary markets..."
Swap the first . and @ and throw out the ".trash" to email me.
Here's my email address for autospammers:

In article ,
Ian Woollard wrote:

I think the Apollo astronauts got something like 1% of a fatal dose on
the way through the belts, and they were going fast. An ion drive takes
weeks to get through. A properly designed ion drive doesn't mind too
much, but any humans on board would be dead unless many tonnes of
shielding were carried at enormous cost.

Or, unless we drain the Van Allen belts.

Cheers,
- Joe

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| Joseph J. Strout Check out the Mac Web Directory: |
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On Mon, 11 Aug 2003 20:01:59 -0500, in a place far, far away, "Paul F.
Dietz" made the phosphor on my monitor glow in such a
way as to indicate that:

Joe Strout wrote:

Or, unless we drain the Van Allen belts.

I insist we now say 'it's tough to drain the Van Allen belts when
you're up to your ass in relativistic electrons'.

Well, sometimes when you're up to your ass in relativistic electrons,
it's hard to remember that your original goal was to drain the Van
Allen belts.

--
simberg.interglobal.org * 310 372-7963 (CA) 307 739-1296 (Jackson Hole)
interglobal space lines * 307 733-1715 (Fax) http://www.interglobal.org

"Extraordinary launch vehicles require extraordinary markets..."
Swap the first . and @ and throw out the ".trash" to email me.
Here's my email address for autospammers:

"Joe Strout" wrote in message
...
In article ,
Ian Woollard wrote:

Joe Strout wrote:
Or, unless we drain the Van Allen belts.

Yes, if that turns out to be practical- it may well be.

Right. It's certainly worth looking into more deeply, once we have
people regularly crossing them.

However you still have the problem that ion drives are very slow.

Very true.

Doesn't it make more sense to carry a limited amount of conventional
rocket propellant to accelerate you to a minimum speed quickly so
the Van Allen belts aren't a problem? For a manned mission, that is.
(And if you're launching from the ground, that should be taken care of
by the launch vehicle.)

Bruce

Bruce Sterling Woodcock wrote:
"Joe Strout" wrote:
Ian Woollard wrote:

Joe Strout wrote:
Or, unless we drain the Van Allen belts.

Yes, if that turns out to be practical- it may well be.

Right. It's certainly worth looking into more deeply, once we have
people regularly crossing them.

However you still have the problem that ion drives are very slow.

Very true.

Doesn't it make more sense to carry a limited amount of conventional
rocket propellant to accelerate you to a minimum speed quickly so
the Van Allen belts aren't a problem? For a manned mission, that is.
(And if you're launching from the ground, that should be taken care of
by the launch vehicle.)

My favorite method of coping with that is to put a manned space station
out in GEO, fly cargo and outbound ships up out of LEO unmanned to
rendezvous in GEO, and fly people out to GEO on a fast transfer GTO
like we do with comsats now.

It seems to be the most overall mass and cost efficient approach.


-george william herbert

George William Herbert wrote:
My favorite method of coping with that is to put a manned space station
out in GEO,

Geo is a bit awkward- it's basically within the outer Van Allen belts,
and it's an expensive and awkward orbit to get to- essentially the same
as the delta-v to reach Mars.

I think leaving fuel on an approximately GTO orbit is superior- GTO has
relatively easy access to LEO, earth escape, lunar orbit, mars orbit as
well as GEO. To pick up the fuel, do a GTO burn from LEO at the right
moment and grab the fuel on the way; you can then burn for wherever
you'd like to go to and minimise the radiation issues on the way.

I think a station in LEO below the worst of any Van Allen belts, and
within range of minimal launch vehicles seems to be a better place for
humans to be most of the time, unless they are going somewhere in
particular; but then you wouldn't normally want to go through GEO.

fly cargo and outbound ships up out of LEO unmanned to
rendezvous in GEO, and fly people out to GEO on a fast transfer GTO
like we do with comsats now.

But nearly all other useful orbits are relatively expensive from GEO.

It seems to be the most overall mass and cost efficient approach.

The GTO - GEO burn wastes fuel if you are going past GEO, it's much
better to do a burn for, say, lunar orbit from LEO or GTO than going LEO
to GEO to Lunar; it's significantly less delta-v (~5km/s). And putting
the station at GEO costs something like 2x as much compared with LEO to
get there even using ion drive tricks for moving chemical fuel around;
and 3x as much compared with LEO using no tricks.

-george william herbert

On Mon, 11 Aug 2003 14:53:51 GMT, Joe Strout wrote:

In article ,
Ian Woollard wrote:

I think the Apollo astronauts got something like 1% of a fatal dose on
the way through the belts, and they were going fast. An ion drive takes
weeks to get through. A properly designed ion drive doesn't mind too
much, but any humans on board would be dead unless many tonnes of
shielding were carried at enormous cost.

Or, unless we drain the Van Allen belts.

Even if we did, as they consist of charged particles wouldn't the sun
just fill them up again.



Christopher
+++++++++++++++++++++++++
"Kites rise highest against
the wind - not with it."
Winston Churchill

In article ,
h (Rand Simberg) wrote:

On Mon, 11 Aug 2003 12:07:07 +1000, in a place far, far away,
(Stephen Souter) made the phosphor on my
monitor glow in such a way as to indicate that:

ISS is a lousy benchmark for an orbital propellant depot.

Then what would you use as your benchmark?

I would use the design of a system whose purpose was to be an orbital
propellant depot, designed by people whose interest was in building
that, rather than padding payrolls in Houston, Huntsville and Florida,
and providing appropriate kickbacks to certain people in the nation's
capital.

An interesting point of view.

So what you're saying is that when NASA designs a space station the
private companies whom NASA calls in to build it for them are not much
interested in designing or building one at all. Too much like hard work, I
suppose. Instead (you seem to be saying) they would rather spend their
share of the loot at Houston, Huntsville or Florida, doubtless while
making periodic visits "to certain people in the nation's capital" to
grease the occasional palm and deliver brown paper envelopes to the needy
souls there.

Presumably were those same companies to go out and build their own
station--an orbital propellant depot, say--instead of "padding payrolls in
Houston, Huntsville and Florida" they would be siphoning off profits to
Chicago, LA, and Manhattan. (The kickbacks would presumably still be need
to keep "certain people in the nation's capital" onside and the subsides
flowing.

Kinda sounds like you just don't think much of private industry, Rand. :-)

--
Stephen Souter

http://www.edfac.usyd.edu.au/staff/souters/