CEV PDQ

Rand Simberg wrote:

Which cuts into your payload weight, and therefore ups your
launch price per pound for large numbers of launches.



That's an interesting theoretical argument, but in practice, what do
you think that Thiokol would do differently in manufacturing a motor
for an unmanned launch that they do for a manned one?



The recovered SRB segments wouldn't have to meet the strict inspection
requirements they now do. After Challenger, Thiokol is probably
extremely paranoid about the recovered booster segments it fills and
ships. I'll bet any scratches or small dents get the segment rejected,
even though they shouldn't really compromise its structural integrity in
any significant way. But they'd be far more likely to use something that
isn't all bright and gleaming on a unmanned launch.
If fact, for warm weather launches, you could use the old style
pre-Challenger booster segments without any real problem.

Pat

wrote:

If we actually intend to do a manned Mars mission we are going to need
a heavy lift vehicle of some sort,

Rand Simberg wrote:

Many believe this. That doesn't render it a fact.

You are going to end up with a lot of launches if you try to do it with
anything smaller than some of the proposed souped-up Delta IV heavy
variants...

Yes. So? A lot of launches is not a problem. It's a *goal*.

Rand Simberg wrote:

I don't see how spending the money to develop a new vehicle that can
only be flown a few times because it's using up a finite amount of
leftover parts can make any kind of sense.



Keep the ETs and SRBs in production; we already have most of the
infrastructure built for a Shuttle derived vehicle- we just need a cargo
container with 2 RS-68s on the back end and something equivalent to an
OMS pod to carry it into orbit- assuming you just don't want to cut the
cargo back a bit and put the modified ET itself into orbit for use as
parts for a station of some sort- you stick the RS-68's on the back end
of the ET, and you can mount a station equivalent to the weight of a
loaded Shuttle on the front of the tank, with the ability to use the
interior of the ET once in orbit in the way the old "wet" version of the
Saturn Workshop was designed to work. Three or four of those will give
you a good sized station for your CEVs to go to.
In fact, if you have living quarters, cargo, or propellants in sections
added to the front end of several ETs, and figure how to refuel them
once in orbit, you can send them on an interplanetary trajectory like
von Braun's old Mars Fleet.

Pat

Ed Kyle wrote:

The Lockheed design can fly earth orbital missions
with just one launch. And, unlike the Russian Kliper
design, the Lockheed CEV brings its earth orbit
propulsion system home with it. That may or may not
be a good thing...



We haven't had any particular problems with the Shuttle's OMS pods other
than the occasional leaky thruster valve.
Nitrous Oxide should be a lot more benign to deal with than the
Hydrazine/Nitrogen Tetroxide we've been using.
I'm pretty sure the Nitrous oxide could cook off, but so could the
Hydrazine for that matter.

Pat

Chuck Stewart wrote:

Sorry, PAT, no conspiracy here. It was quite well known that the
military wanted the crossrange for the "once-around" recon sat polar
orbit launches from Vandenberg. This gave them a reason to buy into
the shuttle, which got the shuttle needed funding.

This also drove the large capacity of the payload bay.



According to "Rebuilding America's Defenses" one of the key aspects of
space usage is to assure U.S. dominance in the space arena; I don't know
if the military wants to go to the Moon ala' Project Horizon, but I can
guarantee you they would like a manned capability to Earth orbit, and
either CEV or Kliper could be turned into a vehicle that has military
capabilities given its ability to maneuver in the upper atmosphere.
The Russians are supposed to be working on some sort of super MARV that
dispenses multiple warheads as it travels at hypersonic velocities in
the upper atmosphere (this is probably what Putin was bragging about a
couple of months back), and we have also taken steps in that direction
with our evolved FALCON Common Aero Vehicle (CAV) project.
Both of these systems could have aerodynamics similar to the Kliper/CAV
in a scaled-down form; or be full sized unmanned variants if intended to
be used as a series of orbiting weapons that can descend into the
atmosphere to attack multiple targets via their onboard RVs when a
military threat looms.
When we got our first look at the BOR unmanned Spiral test vehicle that
landed in the ocean, we thought it might be a MARV for attacking carrier
task forces.

Pat

In article ,
Greg D. Moore \(Strider\) wrote:
So $60 million for a pair of RSRMs, another $60 million for an ET, say $20
million (WAG) for a boattail and engines (all disposable) and then you still
need a standing army for the VAB (to stack all this), the
crawler-transporter, crews for pad refurbishment, etc. pretty soon you're
talking real money.

Exactly. LockMart wasn't going to use *any* of the existing hardware for
VentureStar, and they still concluded that it was cheaper to build new
launch facilities than to buy into maintaining the LC-39 standing army.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

In article .com,
Ed Kyle wrote:
To me this brings to mind another question: Does the CEV
need to be twenty tons? Soyuz was designed in the 60's and weighs
seven metric tons.

Kliper, proposed as a Soyuz replacement, but able to carry
up to six, is projected to weigh 13-15 tons...

BAe's Multi-Role Capsule design, done in the mid-80s, with a capacity
of four people for normal flight and six in a lifeboat configuration,
almost entirely reusable (including propulsion), had an estimated launch
mass of 8t including escape tower.
--
"Think outside the box -- the box isn't our friend." | Henry Spencer
-- George Herbert |

Ed Kyle wrote:



"http://yarchive.net/space/shuttle/launch_abort.html"



Oh, that's pleasant! Did they tell the crew about the little fire problem?

Pat

Ed Kyle wrote:

Kliper, proposed as a Soyuz replacement, but able to carry
up to six, is projected to weigh 13-15 tons, but its
propulsion system will not be recovered (Lockheed has
proposed to make the CEV hardware recoverable). NASA has
listed the maximum liftoff mass of CEV, including escape
systems and fairings that would not go into orbit, to
be 20 tons. CEV doesn't have to weigh that much, of
course.



Kliper was too heavy for a Soyuz booster, and was to use an uprated
Onega booster- a Soyuz booster with a new LOX/LH2 upper stage. This was
later changed to the Zenit booster, which means you could theoretically
launch Kliper from a modified Sealaunch pad.

Pat

Pat Flannery wrote:
Still, how long would one have to get it all stuck together? Days or
weeks?
The Soviet's did a stage (Block D) that used an insulation sunshade
for
it LOX/Kerosene propellant on Proton-Zond and N-1:
http://www.myspacemuseum.com/l1s_2.jpg
But do we have any experience with this sort of thing? The closest
we
came was the canceled Shuttle boosted Centaur stage.

I read somewhere that the original Saturn C-1 S-IV
stage internal insulation design was selected so that
the stage could eventually be used for earth orbit
rendezvous missions, where it would be parked fueled
in orbit for up to 30 days. The S-IV stage was to have
been the Saturn C-2 third stage and the Saturn C-3
third or fourth stage. The internal insulation design
carried over to the Saturn V S-IVB stage.

- Ed Kyle