HDTenEightyP/NetNews huggingface dataset:
From: roberts@cmr.ncsl.nist.gov (John Roberts)
Newsgroups: sci.space
Subject: Re: Comparative $/lb
Date: 30 Dec 92 05:42:04 GMT
Article-I.D.: cs.C0256x.MxH.1
Distribution: sci
Organization: National Institute of Standards and Technology formerly National Bureau of Standards
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU


-From: David.Anderman@ofa123.fidonet.org
-Subject: Re: Comparative $/lb to LEO (Was: Stupid Shuttle Cost Arguments)
-Date: 29 Dec 92 16:31:24 GMT

-The Space Shuttle is the most expensive launch vehicle (per pound in orbit)
-that exists today. I believe this, but cannot prove it.
-...
-However, I freely that I hold this opinion largely on the basis of a gut
-feeling, rather than the available numbers.

Please inform your gut :-) that such comparisons are not very useful unless
accompanied by lots of substantiating math. The markets for Shuttle and
Pegasus are different anyway. The "cost per pound" of launching a KH-12
by Pegasus would be pretty impressive. :-) On the other hand, direct
Shuttle launch to polar orbit would be pretty expensive, since the 
Vandenberg facility is mothballed.

Dennis has pointed out (but nobody else seems to believe) that there are
many ways of figuring cost, based on your application - marginal cost of
a single flight, operational costs, operational plus development for
future launches (which is what's usually used for the Shuttle), and
operational plus amortization of all development costs. There's not a
single number you can point to and say "that number is the cost - use it
for all accounting".

John Roberts
roberts@cmr.ncsl.nist.gov
Newsgroups: sci.space,sci.astro,alt.sci.planetary
From: baalke@kelvin.jpl.nasa.gov (Ron Baalke)
Subject: Mars Observer Update - 12/22/92
News-Software: VAX/VMS VNEWS 1.3-4   
Keywords:  Mars Observer, JPL
Reply-To: baalke@kelvin.jpl.nasa.gov
Organization: Jet Propulsion Laboratory
Date: Mon, 28 Dec 1992 15:29:39 GMT

Forwarded from the Mars Observer Project

                MARS OBSERVER STATUS REPORT
                    December 22, 1992

The C5A sequence continues to clock out and the C5B
sequence is being readied for early January uplink, pending
final confirmation of the date for transition to outer cruise
attitude.

The SCT has successfully loaded the I + 89 star catalogs and
ephemeris updates and the spacecraft is collecting stars while
in the Sun Star Init mode.  The spacecraft will be commanded
back to the  Array Normal Spin mode this afternoon.

The spacecraft is expected to be placed in the outer cruise
configuration in early January, which positions the spacecraft
HGA (High Gain Antenna) and solar array towards earth.  Following
transition to outer cruise, the HGA will be activated.  Following a
short calibration period, the HGA will then be utilized throughout
the rest of the mission for nominal operations.  Until this
transition point, the spacecraft will remain very inactive, with
only star catalog updates planned.

The spacecraft engineering elements and payload instruments
continue to perform well, and within specification.
     ___    _____     ___
    /_ /|  /____/ \  /_ /|     Ron Baalke         | baalke@kelvin.jpl.nasa.gov
    | | | |  __ \ /| | | |     Jet Propulsion Lab |
 ___| | | | |__) |/  | | |__   M/S 525-3684 Telos | Choose a job you love, and
/___| | | |  ___/    | |/__ /| Pasadena, CA 91109 | you'll never have to work
|_____|/  |_|/       |_____|/                     | a day in your life. 

Newsgroups: sci.space
From: aws@iti.org (Allen W. Sherzer)
Subject: Re: Terminal Velocity of DCX? (was Re: Shuttle ...)
Organization: Evil Geniuses for a Better Tomorrow
Date: Tue, 22 Dec 1992 18:11:58 GMT

In article <SHAFER.92Dec22095137@rigel.dfrf.nasa.gov> shafer@rigel.dfrf.nasa.gov (Mary Shafer) writes:

>>You have done the 'creative accounting' here, I'd say. 

>AS> No, it's NASA who is being creative by ignoring billions in cost. BTW,
>AS> if a private company ran their books the way NASA does they would be
>AS> thrown in jail for fraud.

>Like Air France and British Airways?  Writing off the development
>costs of the Concorde so that they could show a profit?

No because the books for Concord balance out. No effort was made to hide
what they where doing and make it impossible to account for costs. Not so
for NASA which constantly changes its estimates on what a flight costs and
hides costs accross a range of line items.

  Allen

-- 
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves        |
|  aws@iti.org     |  nothing undone"                                       |
+----------------------123 DAYS TO FIRST FLIGHT OF DCX----------------------+
Organization: Queen's University at Kingston
Date: Sun, 3 Jan 1993 14:40:37 EST
From: Graydon <SAUNDRSG@QUCDN.QueensU.CA>
Newsgroups: sci.space
Subject: Re: Justification for the Space Program
 <1992Dec28.223226.12849@aio.jsc.nasa.gov>
 <93002.204240SAUNDRSG@QUCDN.QueensU.CA> <C09FDo.K4u@zoo.toronto.edu>
 <james.726039574@menaik> <C09nM6.LMJ@zoo.toronto.edu>

The Lunar advantage is mass, Henry.

If you want a 'hard' satellite, you can do three things - stealth it
(which is pretty ridiculous for a comsat, but not neccesarily for
a weapons platform), give it defenses (a hard problem), or armor it -
design the components to be rad hard, put it in a Faraday cage, and
wrap it in a lot of inert mass.  The Moon has a real advantage when
it comes to shipping inert mass to an Earth orbit, in terms of energy.
This doesn't do them any good unless they have a full industrial
economy there, though.

Taking out a radiation hard satellite with a nuclear weapon, particularly
one that is behind several meters of lunar regolith, isn't all that
easy - no blast effect means either a *big* bang is required (which will
annoy the people whose territory over which is was detonated, never
mind the commercial comsats), or a very close hit.  The very close hit
is basic orbital mechanics, but assumes no counter measures on the
launcher, launch site, etc.

This is all handwaving anyway, since a good analysis involves knowing
the launch costs from earth and the moon *after* that functioning
lunar economy gets put in place.  I'd *love* to have reliable
instances of such figures, truly I would.

Graydon
Newsgroups: sci.space
From: ewright@convex.com (Edward V. Wright)
Subject: Re: fast-track failures
Date: Wed, 23 Dec 1992 23:06:47 GMT
Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA
X-Disclaimer: This message was written by a user at CONVEX Computer
              Corp. The opinions expressed are those of the user and
              not necessarily those of CONVEX.

In <1992Dec20.192544.2996@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:

>Today's overhead is horrible, but $100,000 1940s dollars is only about
>$2 million 1992 dollarettes.... That's about 20 engineers in a Motel 6 
>for six months, no machine shops, hangers, mechanics, flight test equipment, 
>nada.

You think a typical engineer earns $100,000 a year?

I want to work for your company!


Newsgroups: sci.space
From: sbooth@lonestar.utsa.edu (Simon E. Booth)
Subject: Re: DC vs Shuttle capabilities
Organization: University of Texas at San Antonio
Date: Thu, 31 Dec 1992 08:01:40 GMT


   Don't flame me for this, but could someone please tell me if any of my post
ever made it into this newsgroup.  It don't know if they got posted and I
somehow missed the responses or they just got lost.  I never even saw the
original messages I posted.


Simon

Newsgroups: sci.space
From: ewright@convex.com (Edward V. Wright)
Subject: Re: SSTO vs 2 stage
Date: Wed, 30 Dec 1992 16:57:13 GMT
Distribution: sci
Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA
X-Disclaimer: This message was written by a user at CONVEX Computer
              Corp. The opinions expressed are those of the user and
              not necessarily those of CONVEX.

In <C025yp.A1.1@cs.cmu.edu> roberts@cmr.ncsl.nist.gov (John Roberts) writes:

>There's a very good argument for multistage rockets - it makes the mass
>ratio much simpler to manage (see some of the books by Willy Ley).

There's also a very good argument for multistage airplanes -- it makes
the mass ratio simpler to manage.

However, while multistage airplanes have been builting and tested
in trans-Atlantic service, airplane manufacturers quickly realized
that the key to producing a successing airliner was not minimizing
mass ratio, but minimizing operating costs.

In a competitive market, a launcher with a large mass ratio and
low operating costs will beat a launcher with small mass ratio
and high operating costs every time.

Achieving this requires careful attention to sound engineering
principles including, above all, KISS -- Keep It Simple, Stupid. 
What's needed is a simple, reliable design, without bells, whistles,
or stages.


>Unfortunately, it also adds to the complexity and reliability problems of
>the launcher, which is why we'd like to go to SSTO if we can. Thanks to
>advances in technology, it may now be practical, and DC will be a great
>breakthrough if it works. 

Advances in technology, perhaps, but hardly recent advances.  The old
Saturn S-IVB stage could've been turned into a SSTO launcher, with a
payload the size of a Gemini spacecraft.  The "unattainable mass ratio"
is nothing more than an aerospace legend.


>But that doesn't mean designers were foolish to
>use multistage systems in the past - and some applications, such as direct
>flight to the moon without refueling, will probably remain unattainable by
>SSTO for a long time.

Actually, SSTM (you can hardly call it SSTO :-) would be quite attainable
given a nuclear rocket engine with a sufficiently high thrust-to-weight
ratio.  Unfortunately, launching nuclear rockets from Earth was politically
unacceptable even before we had Captain Planet for Veep.













Newsgroups: sci.space
From: henry@zoo.toronto.edu (Henry Spencer)
Subject: Re: SSTO vs 2 stage
Date: Wed, 30 Dec 1992 22:51:28 GMT
Organization: U of Toronto Zoology

In article <1992Dec30.211506.19286@netcom.com> ckp@netcom.com (Charles Pooley) writes:
>So, for the 1st environment, the 1st stage should have the durability to
>cope with the aerodynamic loads and have engines optimised for use in
>atmpsphere...

In practice, even first-stage engines are necessarily a compromise between
atmosphere and vacuum operation.  If you look at the cutoff altitudes of
typical first stages (ignoring little strap-ons and the like), a substantial
fraction of their burn time is spent in near-vacuum.

>The general idea, it seems, is not to take any component or capability
>of the rocket past the point it is needed.  ie, wings, landing gear,
>parachutes, rugged construction etc for low altitude conditions not go
>beyond staging point...

Of course, the same is true for aircraft.  The design of an aircraft's
wings, in particular, is heavily driven by takeoff and emergency-landing
requirements.  (Normal landings, at least for long-haul aircraft, are
made at substantially lower weights than takeoffs and worst-case emergency
landings.)  Would it make sense to build two-stage aircraft, with the
upper stage optimized for high speed at high altitude (plus landing at
relatively low weights after fuel is burned)?  Well, yes, in a way, and
it's even been done occasionally, for research aircraft like the X-15.
But nobody would buy a commercial aircraft built that way, even though
performance would be better, because staging is simply too much trouble
and expense when one-stage designs work fine.

There will be a place for staging throughout the foreseeable future.
No propulsion system likely to be practical soon would be capable of
launching a short-flight-time mission to Pluto without staging; even if
the DCs work perfectly, missions like that will use upper stages.

But it's not necessary or desirable for hauling payloads into low
Earth orbit; we have the technology to do without it, and doing so
has potential to reduce costs quite substantially.
-- 
"God willing... we shall return."       | Henry Spencer @ U of Toronto Zoology
       -Gene Cernan, the Moon, Dec 1972 |  henry@zoo.toronto.edu  utzoo!henry
From: 0004244402@mcimail.com (Karl Dishaw)
Newsgroups: sci.space
Subject: Aluminum as Rocket Fuel?
Date: 2 Jan 93 18:36:00 GMT
Article-I.D.: cs.C08p16.Mts.1
Distribution: sci
Organization: [via International Space University]
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU

>Bruce Dunn writes:
>        This I like!  Molten aluminum (melting point 660 C) can be kept in
>steel tanks.  Using molten aluminum will give a higher Isp than aluminum
>metal. 

How's liquid Al going to work in the combustion chamber?

--forming fine droplets will require a new injector plate--how did that 
work for the Li-F rocket Bruce mentioned?  What kind of surface 
tension does LAl have?  How small would we have to get the droplets to 
be?

--will the LAl burn with LOX directly or will it solidify first and then 
react?  The rocket's performance will be very sensitive to the 
proportion of Al that's burned, by the calculations I ran.  I don't know 
how having a mix of liquid and solid aluminum would affect combustion.  

--the injector plate is going to need an internal heater to keep the LAl 
from solidifying as it passes through and to keep it clean for restarts.  
That's definitely going to be an imported-from-Earth item with all its 
other requirements.


Karl
sold my soul to Uncle Sam . . . now marked down for resale.
Newsgroups: sci.space
From: gary@ke4zv.uucp (Gary Coffman)
Subject: Re: Terminal Velocity of DCX? (was Re: Shuttle ...)
Reply-To: gary@ke4zv.UUCP (Gary Coffman)
Organization: Destructive Testing Systems
Date: Fri, 25 Dec 1992 01:03:42 GMT

In article <ewright.725060424@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
>In <1992Dec20.195520.3587@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:
>
>>It'll still be more cost effective to assemble and test
>>the bulk of space payloads on the ground and boost them to orbit
>>on larger capacity launchers, especially if some effort is put into
>>designing a heavy lifter for low labor costs.
>
>Just as it's more cost-effective to assemble and test
>office buildings at a central factory, then ship them
>to the worksite.  Especially if some effort is put into
>designing a heavy freighter for low costs. ;-)

Indeed, modular housing units *are* cheaper than stick built
housing. Most industrial construction utilizes modular building
systems. Some builders are now using modular sections for
multi-story office structures. The problems with widespread
adoption of these methods isn't technical or economic, it's
archaic building codes. Would you prefer that UAW workers
show up in your driveway and build your new Buick, or would
you rather pay a hundred times less for one from a factory?

Gary

-- 
Gary Coffman KE4ZV          |    You make it,     | gatech!wa4mei!ke4zv!gary
Destructive Testing Systems |    we break it.     | uunet!rsiatl!ke4zv!gary
534 Shannon Way             |    Guaranteed!      | emory!kd4nc!ke4zv!gary      
Lawrenceville, GA 30244     |                     | emory!ke4zv!gary@gatech.edu
Newsgroups: sci.space,talk.politics.space
From: blumb@sage.cc.purdue.edu (Bill Blum)
Subject: Re: The Real Justification for Space Exploration
Organization: SEDS National Board Member
Date: Fri, 25 Dec 1992 10:24:48 GMT

In article <YAMAUCHI.92Dec23004324@yuggoth.ces.cwru.edu> yamauchi@ces.cwru.edu (Brian Yamauchi) writes:
>Asking "why explore space?" is like asking "why feed the starving?",
>"why create art?", or "why do basic science?"  It all comes down to
>basic human drives, and I would argue that the drive to explore is
>just as basic as the drive to help, to create, or to learn.

Good point, Brian.

That's like asking "Why flame people on USENET?"  It's just a basic, human
desire.

>
>The major achievement of Apollo was not Teflon.  The major achievement
>of Apollo was putting a man on the moon.
>
A Purdue Graduate, no less! :)
(Sorry..just had to plug my school :) )

>
>At some level, perhaps the most honest answer to the "why explore
>space?" question is the simplest -- "If you have to ask, you'll never
>understand."

Science has produced many things which have resulted in giant leaps in the
quality of life on Earth.  However, one can't take giant leaps without
making some small steps beforehand.                                    
....20 Jul 1969, Mare Tranquilitatis is my favorite example, but, I'm
biased, and according to some people, i'm a "zealot."  :)  Zealots unite!

-- 
Bill Blum			* "God willing...we shall return."        
Purdue University		* Gene Cernan, The Moon, Dec 1972(BSEE P.U. 56)
School of Nuclear Engineering	* Member of the SEDS National Board
blumb@sage.cc.purdue.edu 	*        Ad Astra Per Ardua!!
From: roberts@cmr.ncsl.nist.gov (John Roberts)
Newsgroups: sci.space
Subject: Re: Breeder reactors
Date: 22 Dec 92 07:05:16 GMT
Article-I.D.: cs.BznFpx.93v.1
Distribution: sci
Organization: National Institute of Standards and Technology formerly National Bureau of Standards
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU


-From: dietz@cs.rochester.edu (Paul Dietz)
-Subject: Re: Breeder reactors (was Re: Justification for the Space Program
-Date: 20 Dec 92 18:53:59 GMT
-Organization: University of Rochester

-In article <1992Dec20.044836.26997@seq.uncwil.edu> session@seq.uncwil.edu (Zack C. Sessions) writes:
->>Speaking of breeder reactors, why doesn't the U.S. have more of
->>them?
->Because they're too damn dangerous.

-Gee, all kinds?  Do remember that there are at least 3 fundamentally
-different classes of breeder reactors that we know are workable (fast
-breeders, thermal breeders and spallation reactors).  The second of
-these already has instances in commercial use (Canadian CANDU PHWRs,
-and the related Indian PHWRs).  These can be operated in the
-thorium/uranium fuel cycle which involves no plutonium, although
-currently they operated as burners with natural uranium.

One concern I've heard concerning at least some of the breeder cycles is that
the fuel produced is more easily converted to bomb-grade material than is the
U238-U235 mix traditionally used in commercial reactors. At the moment, it's
difficult to guarantee that nobody can steal or divert a sufficient quantity
of such a material (if it's widely used) to cause trouble. I believe I've
heard proposals such as deliberately contaminating the fuel with high-level
waste to make it too dangerous for thieves to handle. Do you have any more
information on this aspect? And are there designs where the breeder itself
consumes the fuel it generates?

-With natural uranium currently at $10/lb, and with fossil fuels
-abundant (too abundant, some might say) breeders (as such) don't
-currently have sufficient advantages to overcome political and
-economic obstacles.

How much does uranium sufficiently enriched for use in commercial reactors
cost? (For that matter, how much does U235-depleted uranium cost?)

John Roberts
roberts@cmr.ncsl.nist.gov
From: roberts@cmr.ncsl.nist.gov (John Roberts)
Newsgroups: sci.space
Subject: Re: Shuttle costs vs DC costs
Date: 29 Dec 92 04:03:37 GMT
Article-I.D.: cs.C005zD.5Ls.1
Distribution: sci
Organization: National Institute of Standards and Technology formerly National Bureau of Standards
X-Added: Forwarded by Space Digest
Original-Sender: isu@VACATION.VENARI.CS.CMU.EDU


-From: aws@iti.org (Allen W. Sherzer)
-Subject: Re: Stupid Shut Cost arguements (was Re: Terminal Velocity
-Date: 28 Dec 92 15:46:24 GMT

-In article <72482@cup.portal.com> BrianT@cup.portal.com (Brian Stuart Thorn) writes:
->  You seem to have two sets of measuring systems at work. One which you
->  use for DC, Titan, Delta et al, and one which you use for Shuttle.

-I disagree; I feel I am working very hard to account for both the same
-way.

-However, if you disagree, please post your own numbers. State the rules
-you want to use and apply to both systems fairly. Then show that Shuttle
-is better.

I tend to agree with you, but you keep factoring initial development cost
into cost of using the Shuttle. While that may be interesting in itself,
it's not really relevant to the question of whether DC should be developed.
The cost of developing DC *is* relevant.

As I said before, it's not a "level playing field", but that's the goal DC
has to meet - development costs plus operational costs of DC, versus just
the operational costs (including any *future* development costs) of the
Shuttle.

If it wasn't felt that this is possible, nobody would be working on DC.

John Roberts
roberts@cmr.ncsl.nist.gov
Newsgroups: sci.space
From: ewright@convex.com (Edward V. Wright)
Subject: Re: DC vs Shuttle capabilities
Date: Tue, 29 Dec 1992 16:53:49 GMT
Organization: Engineering, CONVEX Computer Corp., Richardson, Tx., USA
X-Disclaimer: This message was written by a user at CONVEX Computer
              Corp. The opinions expressed are those of the user and
              not necessarily those of CONVEX.

In <1992Dec25.005451.4478@ke4zv.uucp> gary@ke4zv.uucp (Gary Coffman) writes:

>Finally, an intelligent position on SSTO from Allen. I would quibble,
>however, that while there are no known *theoretical* technical issues
>unresolved, there remain numerous practical technical problems to 
>solve in the DC program. 

Gary, numerous practical technical problems arise in *every* engineering
program.  There is no reason to believe that there will be more practical
technical problems involved in building DC than in building the B-777,
except that you *want* to believe that is true.


>That's the type of contingency for which less optimistic management 
>systems provide alternative actions and funding. 

History has shown that the only thing your "less optimistic management
systems" provide is a string of excuses for why a project failed.



Newsgroups: sci.space