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------------------------------
Date: 22 Jul 93 01:47:22 GMT
From: Paul Dietz <dietz@cs.rochester.edu>
Subject: DC-X
Newsgroups: sci.space
In article <1993Jul20.130522.25002@iti.org> aws@iti.org (Allen W. Sherzer) writes:
> The best DC argeument is that it saves money
> and the savings can be spent on social programs.
>
> Now, I personally don't believe that and would fight budget reductions
> if they happened. But it is an arguement that will work.
I don't think this is a very good argument. If you just want to
reduce the cost of currently planned programs, would not expendable
rockets (Proton or BDB) save most of the launch cost, with less
upfront cost and risk than DC? The extra cost of DC has to be
justified by comparison with the marginal savings beyond the low cost
competitor, not against the total savings of not launching on the
shuttle.
Paul F. Dietz
dietz@cs.rochester.edu
"There's absolutely no reason for the kind of prices we're
seeing in space launches ... We've got to get back to basics
if we are to resume our leadership in space." Philip Payne,
former director of Vandenburg launch facilities, Aug. 1987.
------------------------------
Date: Wed, 21 Jul 1993 23:20:29 GMT
From: "Phil G. Fraering" <pgf@srl03.cacs.usl.edu>
Subject: DC-X Prophets and associated problems
Newsgroups: sci.space
mjensen@gem.valpo.edu (Michael C. Jensen) writes:
>I feel compelled to note a historical similarity in recent posting to an
>event in the recent past, and hopefully help aviod a repeat. Currently,
>those DC-X/1 Prohpets are fortelling of a glorious time when the DC
>is flying. Cost per pound will be unbeleivably low. Man-ratings will be
>simple and easy. The system will be so remarkable as to completely
>revolutionize the world and all we know.. or at least something roughtly
>along those lines.
"The shuttle made claims, and failed. Therefore the whole thing
must be impossibly hard."
Why can't we just realize the shuttle itself is a failure and doesn't
say anything about the physics of launching spacecraft?
You've been listening to Ken Hayashida too long.
--
+-----------------------+"And so it went. Tens of thousands of messages,
|"Standard disclaimer" |hundreds of points of view. It was not called
|pgf@srl03.cacs.usl.edu |the Net of a Million Lies for nothing."
+-----------------------+
------------------------------
Date: Wed, 21 Jul 1993 23:23:01 GMT
From: "Phil G. Fraering" <pgf@srl03.cacs.usl.edu>
Subject: DC-X Prophets and associated problems
Newsgroups: sci.space
mjensen@gem.valpo.edu (Michael C. Jensen) writes:
>comment made about the shuttle before it became operational. The exact
>numbers I'd have to look back into these news feeds, but I'm just trying
>to post a gentle "reminder" to use caution in claiming things about the
>operational details of the DC system before they are real. As for projects
>failing, that is not my point at all.. the shuttle certainly is no failure,
>and I hope the same is true of the DC. The "failure" comes in peopel'
>perceptions of the system.. the shuttle didn't live up to ALL of the
>inital claims, and so some label it a failure. The DC faces the exact
>same problem. I don't know where the thread of "a project that has
>failed dooms all others" comes from.. I certanly don't beleive it..
That's the problem I had in Advanced partial elementary differential
equations! I didn't fail! It was the teacher's expectations that did
me in...
NOT!
--
+-----------------------+"And so it went. Tens of thousands of messages,
|"Standard disclaimer" |hundreds of points of view. It was not called
|pgf@srl03.cacs.usl.edu |the Net of a Million Lies for nothing."
+-----------------------+
------------------------------
Date: 22 Jul 93 01:46:51 GMT
From: Henry A Worth <haw30@ras.amdahl.com>
Subject: DC-X thermal protection
Newsgroups: sci.space
In article JFs@zoo.toronto.edu, henry@zoo.toronto.edu (Henry Spencer) writes:
> In article <1993Jul20.123250.21745@iti.org> aws@iti.org (Allen W. Sherzer) writes:
> >>It [crossrange] *is* a silly requirement, for an SSTO.
> >
[...]
> >>Making a landing after a
> >>single polar orbit is no big deal, assuming you aren't stupid enough to
> >>launch from the West Coast...
> >
> >... Consider two SSTO's one with crossrange and another
> >without. Both have equal operational costs and both require 5 ground days
> >of servicing to fly again. Both take off from White Sands Spaceport
> >to polar orbits and return after ASAP to pick up another payload.
> >
> >The first SSTO is back at port 90 or so min. after launch and flys five
> >days later for a total of 73 flights per year. The second SSTO because
> >it lacks any crossrange takes maybe a day to get back to port so it
> >only flies 61 times a year...
>
> Why does it take a day to get back to port? Land at a suitable port
> 1500km to the west and do a suborbital hop to get back. The return
> hop is short and flown at very light weight, so you don't need major
> servicing before doing it. The extra cost and delay should be slight.
> Covering that 1500km as a low-speed suborbital ballistic hop is a whole
> lot easier than doing it with lift at reentry speeds.
>
> That's if you insist on flying the mission as one orbit. In civilian
> applications, you are probably better off waiting 12 hours for a pass
> over White Sands. Among other things, this will let you take your
> time with orbital operations, instead of having to scramble through
> them in 30-40 minutes (you need to make retrofire about half an orbit
> before landing, remember).
In a thriving SSTO launch business there might even be a payload waiting
at the downrange (or is that uprange?) spaceport. With a number of spaceports
around the world an individual SSTO might even haul payloads from several before returning "home", thus reducing the time lost waiting for rentry windows.
With a small fleet, enough spaceports and customers, and a little scheduling, utilization and global availability can be maximized without large downrange requirments (and Trans-Global Spaceways is born ;-) ).
Of course the military will only want to operate from a few secure
locations, or even one in a crisis, with fast turn-around and quick sorties.
So having significant downrange capability will probably be an important capability
for early SSTO's, like DC-1, for which the military is a major potential customer,
and for which a global space freight system is still a dream.
But, for early DC-1 operations, before a global network of spaceports and
customers develop, would the time saved by the downrange landing and return hop
justify the cost of maintaining even a minimal spaceport and ground support?
---
Henry Worth
No, I don't speak for Amdahl... I'm not even sure I speak for myself.
------------------------------
Date: 21 Jul 1993 21:07 CDT
From: wingo%cspara.decnet@Fedex.Msfc.Nasa.Gov
Subject: Hubble SOlar Arrays, How'd they fould up.
Newsgroups: sci.space
In article <22kejf$ogn@access.digex.net>, prb@access.digex.net (Pat) writes...
>
>Everyone knows in aching detail the who's how's and whatfor's
>of the Main mirror problem of the HST. However a larger
>problem has received very little attention. That is the
>Solar Array vibration problem. THese were fabricated under
>contract to ESA by British Aerospace? and now spend
>about 20% of the mission time shaking the damn thing
>around enough that guidance is disrupted.
>
>What i was wondering is how could this kind of design flaw
>sneak past any sort of reasonable test procedure? I would think
>that thermal/vacuum testing would show this kind of behavior
>of the solar arrays?
>
>what happened. did NASA not spec out any testing? or
>did the ESA people bury the problem?
>
>pat
>--
Pat some things simply cannot be tested on Earth. I happen to work
with the Marshall Solar Array guys that work on HST. The arrays were
tested at Lockheed. The whole dang thing was put in a vacuum chamber and
everything possible was done at British Aerospace, the vendors of the
array. The problem is that the thermal transient of going from light
to shadow in zero g causes a 11 Hz oscillation in the arrays. There is no
way to simulate this on earth, none at all. There is no evidence that
anyone anywhere did anything wrong. In hindsight maybe the job could have
been done differently, but it is only the on orbit experience of the
operation of the arrays that provided the information that allows them
to build better arrays this time.
Dennis, University of Alabama in Huntsville
By the way Allen posting on another message I saw from you. I do believe that
the DC big engines will work. What I have said over an over is that it is
not nearly as simple of a task as you portray it to be. It will cost more and
the schedule will slip because of it. By the way I am calling to register
my support.
------------------------------
Date: Thu, 22 Jul 1993 02:19:29 GMT
From: Dave Michelson <davem@ee.ubc.ca>
Subject: Info about old Diamant wanted
Newsgroups: sci.space
In article <1993Jul14.162041.15579@il.us.swissbank.com>, andreas@black_uster
(Andreas Forrer) writes:
>
> I'm looking for ANY kind of information about a French rocket called
> "Diamant BP-4" from 1975. Any hint is welcome, including pointers to
> possible sources.
* 1962 -- France forms the Centre National d'Etudes Spatales and work
begins on Diamant booster
* 1965 -- France launches a 40 kg satellite from Hammaguit, Algeria
using a Diamant
* 1967 -- France moves launch operations to Kourou in French Guiana
and work begins on Diamant B
* 1970 -- First flight of Diamant B (carrying a West German satellite)
* 1972 -- Work begins on Diamant BP-4
* 1975 -- First flight of Diamant BP-4 (carrying a geodetic satellite)
Diamant BP-4 Specifications
===========================
* designed to lift 200 kg into
a low earth orbit with an altitude
of 186 miles
---------------------------
Valois First Stage
Thrust: 88,200 lb
Fuel: UDMH
Oxidizer: N2O4
---------------------------
Rita 1 Second Stage
Thrust: 39,690 lb
Solid Fuel
* derived from the upper stage of
the French MSBS fleet balistic missile
* solid fuel verniers and Freon injection
for thrust vector control
----------------------------
Rubis Third Stage (?) (assuming that the Diamant third stage was used
as is on the Diamant BP-4)
Thrust: 11,685 lb
Solid Fuel
-----------------------------
Hope this gets you started....
--
Dave Michelson -- davem@ee.ubc.ca -- University of British Columbia
------------------------------
Date: 22 Jul 93 04:51:30 GMT
From: Carl Rigg <cwr@theory.asd.sgi.com>
Subject: Info about old Diamant wanted
Newsgroups: sci.space
In article <1993Jul22.021929.8654@ee.ubc.ca>, davem@ee.ubc.ca (Dave Michelson) writes:
|> Newsgroups: sci.space
|> From: davem@ee.ubc.ca (Dave Michelson)
|> Subject: Re: Info about old Diamant wanted
|> Organization: University of BC, Electrical Engineering
|> Date: Thu, 22 Jul 1993 02:19:29 GMT
|>
|> In article <1993Jul14.162041.15579@il.us.swissbank.com>, andreas@black_uster
|> (Andreas Forrer) writes:
|> >
|> > I'm looking for ANY kind of information about a French rocket called
|> > "Diamant BP-4" from 1975. Any hint is welcome, including pointers to
|> > possible sources.
|>
|>
|> * 1962 -- France forms the Centre National d'Etudes Spatales and work
|> begins on Diamant booster
|>
|> * 1965 -- France launches a 40 kg satellite from Hammaguit, Algeria
|> using a Diamant
|>
|> * 1967 -- France moves launch operations to Kourou in French Guiana
|> and work begins on Diamant B
|>
|> * 1970 -- First flight of Diamant B (carrying a West German satellite)
|>
|> * 1972 -- Work begins on Diamant BP-4
|>
|> * 1975 -- First flight of Diamant BP-4 (carrying a geodetic satellite)
|>
|>
|> Diamant BP-4 Specifications
|> ===========================
|>
|> * designed to lift 200 kg into
|> a low earth orbit with an altitude
|> of 186 miles
|>
|> ---------------------------
|>
|> Valois First Stage
|>
|> Thrust: 88,200 lb
|>
|> Fuel: UDMH
|> Oxidizer: N2O4
|>
|> ---------------------------
|>
|> Rita 1 Second Stage
|>
|> Thrust: 39,690 lb
|>
|> Solid Fuel
|>
|> * derived from the upper stage of
|> the French MSBS fleet balistic missile
|>
|> * solid fuel verniers and Freon injection
|> for thrust vector control
|>
|> ----------------------------
|>
|> Rubis Third Stage (?) (assuming that the Diamant third stage was used
|> as is on the Diamant BP-4)
My information shows that the Rubis P-0.7 was used on Diamant and that
Rubis P-0.6 was used on Diamant B and BP-4.
The difference between the B and the BP-4 was the replacement of the Topaze
second stage by the P-4 RITA 1 second stage.
The only common stage between the Diamant and the Diamant B was the
Topaze second stage. Diamants first stage was an Emeraude and stage 3 was
Rubis P-0.7.
thanks
Carl
|>
|> Thrust: 11,685 lb
|>
|> Solid Fuel
|>
|> -----------------------------
|>
|> Hope this gets you started....
|>
|>
|> --
|> Dave Michelson -- davem@ee.ubc.ca -- University of British Columbia
--
------------------------------
Date: 21 Jul 93 23:19:32 GMT
From: Dennis Newkirk <dennisn@ecs.comm.mot.com>
Subject: The U.S. and Mir
Newsgroups: sci.space
In article <105755@hydra.gatech.EDU> ccoprmd@prism.gatech.EDU (Matthew DeLuca) writes:
> I've seen a number of plans in the past for various methods of saving
>money on Freedom that use Mir in various capabilities, starting with using
>it as a 'construction shack' and going as far as docking our hardware to
>it. My question is this: has anyone actually talked to the Russians about
>these ideas? Seems like everyone's favorite magic wand recently is to invoke
.....
> Besides, would we really want to dock Freedom to Mir? Considering the
>declining state of health of the station, particularly the core module, it
>doesn't seem like it would be a wise idea.
Buzz Aldrin was one person who has promoted docking Freedom and Mir elements
together recently. In his case it was for servicing or crew transfers,
I think. He got quite a bit of press during the redesign teams work, but
I think he was mostly ignored by those in power, or so the articles said.
Mir is not suited to aid building the Freedom design. Its just not built
with intensive orbital construction in mind. It is also to old to
seriously consider in plans for Freedom operations a decade or so from now.
Mir 2 needs to be considered now in Freedoms design. Maybe we can
instead bring the Russians onto Freedom in the form of modules or
experiments, crew and launch services. After all, Mir 2 is not
built yet and I'm sure modifications could be made to their plans.
Getting them back down to 51.6 degree orbits will be a challange.
They have announced Mir 2 will be in a 65 degree orbit. We might
have to also give Kazakstan a piece of the action to get to 51.6.
Freedom could also be changed too but this may be more disruptive
than its worth. It's certianly worth a look at getting the Russians
and NASA together in space station plans and operations. On the other
hand, even with funding trouble, if I were in charge of Mir 2 I'd be
pretty hesitant at getting involoved in any way with Freedom. Talk
about a rock and a hard place... But, its not clear Mir 2 will be
funded and operated in future years, just as its unclear if Freedom
will ever be funded and operated as envisioned now. Its possible
that the US, Europe, Japan, Canada, and Russia will yet have to find
a way to work together on a single station to get anything done in the
not to distant future.
Mir is not totally useless since it is operating now and can easily
be used for long duration NASA missions until Freedom is ready. This
is what the Germans, French and ESA are doing with Mir, and NASA
has its first mission to Mir planned for 1995 so they're on the
right track and the 1995 mission should pave the way to more missions
in the future.
Dennis Newkirk (dennisn@ecs.comm.mot.com)
Motorola, Land Mobile Products Sector
Schaumburg, IL
------------------------------
Date: Thu, 22 Jul 93 01:04:00 BST
From: h.hillbrath@genie.geis.com
Subject: Von Braun Team Work
> Date: 21 Jul 93 02:31:31 GMT
Pat <prb@access.digex.net>
Writes:
> he feels the german scientist community were poorly treated
> after the moon race was over. on that point he has a point, he
> just can't see why some of us aren't terribly sympathetic
> towards them.
I might have changed a few things in the way that was run, if I had
been king, but, however one looks at it, or what ever one thinks
about sympathizing with them, it is pretty hard to justify the
situation with Rudolph. If he was a war criminal, we knew as much
in 1945 as we know now, but we were willing to let him come and be
a big honcho in the Saturn program, and only deport him when he
was of no more value (in someone's opinion.)
> he said he was standing underneath the
> vessel as they were loading it to 135% of rating, when he decided
> that was macho enough and time to go to the shelter, as he walked
> out a rivet just dinged his ear.
That is not so much what I would call "macho," it think the word is
more like "stupido."
As it happened, the son of a guy who wrote one of my collage text
books (it is amazing how well one feel one knows the authors of ones
texts, even when one hasn't met them, sort of like networking.),
while I was taking the course, was watching a test of an liquid
oxygen tank which he had apparently designed. It was being
pressurized with liquid nitrogen, and catastrophically failed. He was
instant popsicle.
The first test that I ever was responsible for the requirements for
(but not the conduct of) had a split hose that soaked me with
kerosene, but, other than a persistent odor, I had no real effects,
good that we were not smoking at the time. And, I have had a few
other adventures, a 300 pound nozzle thrown over the blockhouse I
was watching from, etc. I am not standing under any test article, me!
> but he said the noise of the
> stage undergoing loading was remarkable.
Has led to a whole new cult, "acoustic emission analysis." I never
listened to a whole tank, but my parts seldom made much noise,
when we could bust them, at all.
What really makes a lot of noise is a composite pressure vessel. They
sound like machine guns when they start getting close to rupture.
> it will certainly aid in the discourse to have a few grey heads
I don't have much hair of any sort left, but what I do have is, indeed,
