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Date: Tue, 15 Dec 92 05:00:04
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #546
To: Space Digest Readers
Precedence: bulk
Space Digest Tue, 15 Dec 92 Volume 15 : Issue 546
Today's Topics:
absolutely, positively overnight
DC vs Shuttle capabilities (2 msgs)
DoD launcher use
fast-track failures
Mach 8+ Space/Spy Plane?
Sea Dragon?
Space Tourism
SSF Progress
SSF Progress 1 of 2 (Was: One small step Space Activist)
Terminal Velocity of DCX? (was Re: Shuttle ...)
Titan IV
Titan IV Costs (2 msgs)
What is a VSAT?
what the little bird told Henry (2 msgs)
Welcome to the Space Digest!! Please send your messages to
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----------------------------------------------------------------------
Date: 14 Dec 92 17:22:52 GMT
From: "Edward V. Wright" <ewright@convex.com>
Subject: absolutely, positively overnight
Newsgroups: sci.space
In <Bz4841.Ar8@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>I don't seriously expect that a DC-1 would ever become Air Force One,
>actually. Not because it's dangerous, but because it's too *small*,
>and because servicing facilities for it won't be nearly as common as
>those for 747s for a long time. But I rather suspect it would be rather
>less than twenty years before the president rides in one. He *is* the
>boss, after all...
"Air Force One" is just a call sign for whatever plane the President
happens to be riding in. The Air Force has an entire squadron of planes
which, at one time or another, may be Air Force One. The big 707 (now
747) is the most famous, but not every trip requires something that
large.
A DC-type vehicle would probably find use because it would allow
certain types of diplomatic missions that are impossible today.
Remember shuttle diplomacy? If the President, or one of his
advisors, can fly halfway across the globe, attend a top-level
meeting, and return to Washington, all in one afternoon, I think
that's a capability that would be used. If nothing else, it would
allow short-notice meetings to be held before the press figured out
what was going on.
------------------------------
Date: 14 Dec 92 17:33:48 GMT
From: "Edward V. Wright" <ewright@convex.com>
Subject: DC vs Shuttle capabilities
Newsgroups: sci.space
In <3kf2v=-@rpi.edu> kentm@aix.rpi.edu (Michael V. Kent) writes:
>Delta Clipper's projected 2-day on-orbit time is too short for Spacehab
>work, especially if you have a space station.
The two-day endurance is based on consumables. You could extend it
considerably by carrying extra consumables in lieu of some cargo (or
docking with a second DC acting in a consumables-tanker role).
------------------------------
Date: 14 Dec 92 17:59:34 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: DC vs Shuttle capabilities
Newsgroups: sci.space
In article <g9g2v_p@rpi.edu> strider@clotho.acm.rpi.edu (Greg Moore) writes:
> You missed my point. If your crew compartment is in the cargo
>bay, where do you put the satellite?
First of all, which crew? The flight crew rides in the cockpit which is
above the cargo bay. If more crew are needed, then the satellite can
ride in the part of the cargo bay not used by the extra crew.
If it turns out that this isn't roomy enough, then you use the technology
developed under DC to build a larger vehicle. After all, DC will be a usefull
piece of technology but it isn't the only spaceship which will ever be built.
> I eliminated some stuff above, but wanted to add some stuff here.
>Actually, plummeting launch costs may contribute to lower payload costs
>since people will be willing to build a less fault tolerant system
>knowing that if it fails, they can launch another cheaply.
Exactly.
>As for on-site repair, for now DC-? fails for the same reason that
>the Shuttle normally does, it can't get up to GEO, you need a OTV...
Although a DC with a robot arm and some avionics changes may be the
OTV. Certainly the engines for a DC will be just what an OTV needs.
>>> Also, as for retrieval, the Shuttle has shown that it ain't
>>>easy to do. Will a two day on-orbit time be enough?
>>It may take modifications to the DC. At the very least you need to add
>>a robot arm and an airlock.
> Granted, but that's not what I meant. Will you have enough time
>to rendevous and capture the satelite? It took what 3 days for the
>shuttle to capture Intelsat VI? That's aday more than DC-?.
Load the pallet with some extra power sources, add some solar cells and
your all set.
>Also, what type of fuel margin would DC-1 have for IN-orbit
>manevours?
DC-Y has a fair amount of fuel for on orbit delta V but I don't
remember the exact numbers. How much DC has will depend on the
design requirements and who pays the bills.
But note that on a DC-Y you can power the fuel cells, main engines, and
RCS from the same source. This allows you some very powerful tradeoffs.
>(I realize it has enough for landing, and of course
>you don't wnt to cut into that for safety reasons.)
At least enough to get back to the orbital fuel dump.
> Use it yes, but use it for what it can be used for economically.
>Let's see, we've added an airlock, an arm, additional on-orbit capacity.
>Hmm, that adds up, and add complexity. Yes, let's ok at possibilities,
>but not claim t they are definites.
Agreed. But they don't look all that hard given a working DC.
>>My view is that we use the basic DC as a 'bus' which can be modified in
>>small ways to meet diverse missions. Costs are cut because the same assembly
>>lines are used to make DC1-EOT (Earth orbit transfer), DC1-OMV, and DC1-LM.
> I have a question about this. EOT and LM should require roughly
>the same amount of fuel, no?
Pretty much.
>But how economical is it to transport that fuel TO orbit? Am I correct in
>remembering you saying about 10 DC-1 flights?
Yes it would take roughly 10 DC flights to carry up the fuel. Soon however
the availability of lunar oxygen and perhaps hydrogen will greatly reduce
that cost.
The bottom line however is that it is still a lot cheaper than the current
plans.
> Also, does it make sense for the DC1-EOT and OMV and LM the same.
Not 100% the same. For an OMV I would strip off the thermal protection
system, add attach points outside for additional fuel and hardware (like
arms), I might look at lining it with solar cells for more power. For a LM
I think you would need to provide better insulation to reduce fuel boil off,
replace the landing gear to give it a larger footprint (like the Apollo LM),
and beef up the TPS for aerobreaking.
This will allow us to use the same core vehicle for multiple applications
which will allow development to be amortized over more vehicles and reduce
construction costs since we are building more core vehicles.
Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves |
| aws@iti.org | nothing undone" |
+----------------------131 DAYS TO FIRST FLIGHT OF DCX----------------------+
------------------------------
Date: 14 Dec 92 14:41:35 GMT
From: Gary Coffman <ke4zv!gary>
Subject: DoD launcher use
Newsgroups: sci.space
In article <1992Dec13.212814.14887@iti.org> aws@iti.org (Allen W. Sherzer) writes:
>In article <1992Dec13.183545.9958@ke4zv.uucp> gary@ke4zv.UUCP (Gary Coffman) writes:
>>We're talking about Iraq right? No air opposition right? Complete Coalition
>>domination of the airspace right?
>
>I would hate to base all US defense donctrine on the assumption that ALL air
>wars will be just like Iraq. BTW, despite our domination of the air, coalition
>aircraft WHERE shot down.
I agree that not all conflicts will be as easy as the Gulf War and that
satellite recon is very valuable, especially for strategic recon. But the
origninal message that I questioned said that the Space Command commander
during *Desert Storm* said he needed tactical satellite recon *for that
conflict*. And yes, A10s and Tornados doing low level attacks were lost
to ground fire in Desert Storm as well as a few other operational type
aircraft like an AC130, but as far as I know, no recon aircraft were lost.
>For many applications satellites are more productive. They provide faster
>responce and allow scarse aricraft to be better utilized.
see below
>>What can a satellite do for tactical recon that a SR71 can't?
>
>Updates of the tactical situation with SR-71 would take about 6 to 8 hours
>to get and would be several hours old by the time they get to the local
>commanders. Satellite images take seconds to get and are fresh. In the Gulf
>war, images just a few hours old would have been useless.
But this was exactly my point. LEO satellites pass over the same ground
track twice a day. So if you need pictures of a given battlefield, you
wait for the satellite to pass over the spot, up to 24 hours if you need
a daylight picture, up to 12 hours if you'll take any picture. Then, unless
you have realtime downlink in the footprint of the satellite, very close
to your target, you wait for the satellite to pass over your downlink station
and download the image. This can take up to another 12 hours. You can
launch ramp ready recon aircraft in 10 minutes if necessary, though
normally you'd schedule recon as part of an operational timetable.
You can get back immediate Mark I eyeball reports during the mission
and photos as soon as the aircraft returns.
To return tactical target data, like a damage report on a bridge, you
need fairly high resolution. With a satellite, that's KH-11 or KH-12
class optics. That's still too expensive to toss up on whim for a one
shot look. Aircraft with mounted optics of much less precision and cost,
due to the lower altitude, can get a picture and come back to base to
be used again and again. Now if the threat level over the target is
*really* high so that not even a SR71 or F117 has a chance of survival,
and the information is vital, then you could expend a KH-12 class satellite
to gather it. Seems that if DC-1 works, you'd just use *it* so you could
get your expensive optics back instead of expending a satellite.
I know there's lots of interest in lightsats and microsats for intelligence
gathering, but to date none have flown with the level of optics needed
for damage assessment on a tactical level. I'm guessing they *can't* because
the optical platform has to be too large. But that kind of information
is classified so I can't say that for sure. A GEO satellite with superb
optics might be able to give you realtime data, but that's not a DC-1
payload. That's at least a Titan IV payload and a large ground support
center to operate the satellite and process the data. It's certainly
not something you throw up on whim for tactical data gathering, it's
a major national resource costing at least as much as Hubble. Even if
the launch were free, it would still be very expensive.
Gary
------------------------------
Date: 14 Dec 92 14:53:51 GMT
From: Gary Coffman <ke4zv!gary>
Subject: fast-track failures
Newsgroups: sci.space
In article <Bz7wLM.6s8@zoo.toronto.edu> henry@zoo.toronto.edu (Henry Spencer) writes:
>
>Just which aircraft were you thinking of, Gary? I can think of one
>aircraft that had a bad performance shortfall but was redesigned and
>continued into a successful program (the F-102). I can't think of
>*any* F-series "gap" in the last 40 years that fits your description.
Yeah, bad line of argument, most of the systems that made it as far
as being assigned a number weren't technical failures even if they
were market failures. Actually I was thinking of the P-39 when I
wrote that. That aircraft made it into production, but was a dismal
failure at meeting it's procurement goals. It started out as a 5,000
pound turbosupercharged high performance all altitude fighter and
was sold to the Air Corps as such. But by the time it was delivered,
it was 50% overweight, had the turbosupercharger deleted, had poor
rate of climb, and a low service ceiling. This was an example of
fast tracking from a prototype to production without working out
all the bugs required to make it a practical fighter.
Gary
------------------------------
Date: 14 Dec 92 15:58:06 GMT
From: Kenneth D Rolt <kdrolt@athena.mit.edu>
Subject: Mach 8+ Space/Spy Plane?
Newsgroups: sci.aeronautics,sci.space
Rich Silva [rich@locus.com] wrote:
>I was in Joshua Tree national forest last May when I saw a plane in the upper
>atmosphere fly across the sky about as fast as metors do I didn't here any
>sonic booms but I't couldn't have been a jet airliner it was moving too fast
>I did notice it's contrail was lumpy like -+-+-+-+-+-+ like a pulse.
a possible reason why you didn't hear anything {i.e. no sonic boom, and no
thrust noise} was that the sound from the mach cone and from the jet was
refracted too much away from the ground due to a sound speed profile in the
atmosphere: the sound speed for the *aircraft* altitude was slower than the
speed of sound on the ground, so the sound waves refracted enough for you to
be in an acoustical shadow zone. the same phenomenon exists in the ocean. of
course, maybe you really didn't see anything at all :) -ken
-----------------------------------------------------------------
| R 2 Real Monza kdrolt@athena.mit.edu |
| |__| grad student !! |
| | | '64 Corvair Convertible mit ocean engineering |
| 1 3 underwater sound |
-----------------------------------------------------------------
------------------------------
Date: 14 Dec 92 16:18:11 GMT
From: Thomas Clarke <clarke@acme.ucf.edu>
Subject: Sea Dragon?
Newsgroups: sci.space
I see many references to Bob Truax's Sea Dragon design.
Can anyone point me at a reference, or post a summary
of the Sea Dragon?
Thanks.
--
Thomas Clarke
Institute for Simulation and Training, University of Central FL
12424 Research Parkway, Suite 300, Orlando, FL 32826
(407)658-5030, FAX: (407)658-5059, clarke@acme.ucf.edu
------------------------------
Date: Mon, 14 Dec 1992 16:54:44 GMT
From: Nick Haines <nickh@CS.CMU.EDU>
Subject: Space Tourism
Newsgroups: sci.space
A bloke called (hmm, something like Drunken Loony, ah, I remember)
Duncan Lunan did a presentation on space tourism (the economics and
practicalities) at the Brighton Worldcon in 87. He had figures showing
that at $1 million a head you could get at least $100 million for an
orbital hotel (maybe it was $200m), without having to push the
advertising too hard. If you can get the price down to $10000 you can
get several $bn.
Think it was Duncan Lunan (from Imperial (?) College, London). Ask
around on the .sf. groups, I bet there are others there who remember
the talk.
Nick Haines nickh@cmu.edu
------------------------------
Date: Mon, 14 Dec 92 09:14:44 -0800
From: ganderson@force.decnet.lockheed.com
Subject: SSF Progress
I have to comment on the dialog between Allan S. and L.W. on the relative
progress of MacDonnell Douglas' WP-02. I have missed some of the
conversation but having read many of Alan's past missives and can't
surmize the general bent of his comments.
First of all, I agree with the rebultal that the Space Station budget and
design has been enything but stable. NASA received "almost" full funding
this year for the first time in about 4 years. The pertinent point is
that "full" funding is determined AFTER NASA has squeezed their contractors
to the wall as to schedule and budget. So, ANY reduction in the proposed
budget value will have some effect (there is no breathing room). As an
example, WP-04 was asked to quote (right after restructure) to a "Just
in Time" building schedule. To anyone who knows anything about designing
and building a spacecraft, JIT principles do not mean anything except that
you are accepting more schedule risk. In the case of the Solar Arrays, of
which I have very intimate knowledge, this has meant implementing a very
cost ineffecient subcontractor delivery schedule of solar cells, bypass
diodes, motor drive assemblies, etc. It has also meant greater and greater
schedule risk as the design process has been delayed by relatively minor
glitches in the development test process as can be expected with any
development program (but which Alan tends to ignore when he cites costs
of developing new launch systems.)
Second, I would like to comment on the question of CDR design maturity. It
is true that it is a guideline that 90% of all drawings be complete by the
time of the CDR but, at least in the case of WP-04, there is nothing written
into LMSC's subcontract requiring this value. The 90% is an industry rule
of thumb that must be tempered by two factors; 1) Customer restraint in
changing requirements and 2) the relative number of structural vs.
mechanism drawings. The second item is common sense. You can sketch the
cross-sections of major structural elements and describe their material
make-up and most engineers and analysts can verify the strcture will do
what is required (and of course, the fastening methods), however,
mechanisms must be scrutinized carefully for lubricants, surface finishes,
tolerances, meterial compatablity, etc. Therefore, a mechanisms intense
program will need to have a greater number of design drawings complete by
CDR to "adequately disclose the design" as the phrase usually is place
into contracts says.
Customer restraint in changing requirements is where NASA is falling down
very heavily (the bigger they are, the harder they fall.) It is not that
NASA is changing their minds as to what they want, it is that NASA is just
now getting together to find out whatthey require. As an example, take
plume loading on the Solar Arrays (again, a subject that I am very familiar
with.) The actual loads due to pluming were formally placed on out contract
in January.....of 1992!!! This is 3 years into the design process and
after ALL the PDRs and some of the subcontract CDRs. It is not that no
one knew that plume loads were going to happen (we'd been screaming about
not having a requirement for years) but it took that long for Mission Ops,
(JSC) and Power Systems (NASA Lewis) to come up with numbers. I have often
heard the arguement that designers should have "put more margin" into the
design to envelope this load case. If you really want to be flamed, state
that arguement....
Anyway, the bottom line is, when you are faced with multiple redesigns that
effect most of the design drawings that are required, the number of
drawings that are "complete" at CDR can be compromised if the schedule of
the CDR (and first element launch) is critical. Again, it just assumes
more risk to schedule when problems are discovered downstream of the
CDR and after production has begun.
A final comment to my second point: NASA has still not settled requirements.
At the Soalr Array Wing CDR which took place December 1-4, 1992, NASA Lewis
and NASA JSC and Rocketdyne (WP-04 prime contractor) were still in disagree-
ment over the plume loading and other shuttle induced loads on the array
(docking, berthing, Asronaut induced truss oscillations...) The "on
contract" solution is to retract the arrays during all early mission (pre-
permanently manned capability: PMC) shuttle docking proceedures. NASA JSC is
very much against this approach and I believe NASA REston is in agreement
with them, for obvious reasons of practicality. As of today, there are NO
contractural requirements for dockingor bething loads on the solar arrays
but there are studies going on about how to make the array mast withstand
these loading scenarios.
My third and final point is about the integration of the station. A very
telling point was a converstation that accured during the Solar Array Wing
CDR. During discussions about what configuration the station is in
during the second shuttle assembly flight, it was revealed that both
arrays are deployed partially in what is called a "ready to deploy"
configuration. Unfortunately this is not how the thermal analysis
was done as both Rocketdyne and LMSC had a different configuration in
which one array was fully stowed and the other in this "ready to deploy"
configuration. When asked by Rocketdyne how NASA intended to flow down
this requirement to its contractors, NASA's response was that the new
configuration was in the TOS (I later found out that this is a Technical
Operation Support document). Unfortunately the TOS is not on Rcoketdyne's
contract. When I enquired of JSC representatives as to who had
juresdiction over this TOS, he said that it was not an official document
buut something that a few concerned JSC engineers put together because
they did not see the needed work being down as to the piece by piece
analyssis of the on orbit configuration as the buildup progresses
(remember, every element left up there has to act like a controllable
spacecraft.) So the bottom line is that their seems to be a very large
lack of "big picture" work fromthe station system design standpoint. If
consolidating everything at JSC will fix this, then more power to it all.
Now that I have provided more fodder to Allan to call for the concellation
of space Station, I might as well sign off. Feel free to respond to
my address below.
Grant Anderson
Ganderson@jedi.decnet.lockheed.com
Design Project Leader
Space Station WP-04
Lockheed Missiles and Space Co.
Sunnyvale, CA
All oppinions expressed are my own. Facts speak for themselves. Fools
speak for each other.
------------------------------
Date: 14 Dec 92 18:24:23 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: SSF Progress 1 of 2 (Was: One small step Space Activist)
Newsgroups: sci.space
In article <n116bt@ofa123.fidonet.org> Wales.Larrison@ofa123.fidonet.org writes:
>>... Four years later, as a result of cost
>>overruns, Work Package 02 now weighs in at $4.9 billion -- A 250%...
> Hmm.... I'm not going to dispute these numbers, but there's a
>distinct difference between "cost overruns" and "customer directed
>changes".
Not from my point of view. Most of this happened AFTER the redesign.
Wether it is the result of NASA changing its mind or MD not up to the
task we have a project out of control.
Either way we have a station which is taking longer and longer to build
and costing more and more. The process being used simply doesn't work.
>Furthermore, a large chunk of these overrun costs seem
>to be in General & Administrative cost categories (G&A), not in the
>technical work performed.
So what?
> Now, funding and design for the SSF has not been rock stable
>either for the past 4 years. I seem to remember at least 3 of the 4
>budget requests being cut, funding restrictions placed on a couple,
>and a major Congressional-directed redesign of the SSF.
Cuts have been minor and shouldn't have resulted in these sort of
increases and delays. Also, the redesign was well over two years
ago. Plenty of time to produce a good schedule.
> I'm not apologising for MD, but I would like to present some data
>from the other side of the story.
Fair enough but I should point out that the SN article was not the
only source I used. A source at NASA provided the rest.
> What Allen didn't report, and what I see just as significant,
>was that SN reported the NASA Inspector General had started a
>separate audit to see if the restructuring of the Work Package 2
>contract was done properly by NASA JSC.
Also, so what? This problem has been brewing for years. It looks like
this audit only began when SN started looking around. Why the delay?
Also, the real problems aren't going to appear in any audit. The NASA
auditor will consider $10,000 to deliver a pound to LEO a fair price.
He won't blink at overhead rates which would give most CEO's a heart
attack. He won't give a second thought to the effort and cost associated
with a 1,000 page proposal when the equivaltnt commercial proposal would
be 60 pages.
Auditors audit the process. When it is the process which doesn't work,
they won't find it.
>>Worse yet, Work Package 02 is as much as 18 months behind schedule...
> "The company informed NASA earlier this year that it could
> provide 700 drawings before a design review begins next year,
> but under NASA pressure agreed to provide 2700, NASA officials
> said. Only 1100 are needed for the design review, according to
> Parkinson [The MD general manager for space station project
> control], so MD will exceed that target."
They provide 700 drawings where 1100 is the minimum and they agreed
to 2700. How can that be said to exceed any target?
> "Aaron [The space station program manager at JSC] said that some
> aspects of the work package are about a month behind, but
> denied there is any lag on the order of 18 months in his
> portion of the program.
Sources have confirmed the 18 month behind schedule number. I stand by it.
I believe their status on drawings (see above) also tends to confirm that
they are a lot more than a month behind schedule.
> In my opinion the real make or break for MD will be how MD
>conducts itself at the work package 2 Critical Design Review (CDR)
>this coming year.
Except that under the JVIT system it will be much easier for the people
responsible (JSC and MD) to cover up lack of progress since there will
be no independent program office.
Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves |
| aws@iti.org | nothing undone" |
+----------------------131 DAYS TO FIRST FLIGHT OF DCX----------------------+
------------------------------
Date: 14 Dec 92 18:28:20 GMT
From: "Allen W. Sherzer" <aws@iti.org>
Subject: Terminal Velocity of DCX? (was Re: Shuttle ...)
Newsgroups: sci.space
In article <ewright.724353431@convex.convex.com> ewright@convex.com (Edward V. Wright) writes:
>Also note that the cost of one Shuttle flight is about the same
>as the entire DC development program.
Not quite. It wold take about 1.5 years of Shuttle funding to develop DC. Now
for the cost of a Shuttle flight, you could run a program to answer all the
open technical questions and have enough left over to buy a Titan IV to
launch the payload which would have gone up in the Shuttle.
Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves |
| aws@iti.org | nothing undone" |
+----------------------131 DAYS TO FIRST FLIGHT OF DCX----------------------+
------------------------------
Date: 13 Dec 92 20:40:48 GMT
From: Bruce Watson <wats@scicom.AlphaCDC.COM>
Subject: Titan IV
Newsgroups: sci.space
In article <71519@cup.portal.com| BrianT@cup.portal.com (Brian Stuart Thorn) writes:
|
|That was Number 6. I never heard anything about it, and was mildly
|surprised to read about it in this weeks AVLeak and Space News. It
|got no attention from the media (to the USAF's delight, no doubt), not
|even with the last military shuttle mission launched a few days later.
It made our media. Denver Post: _Titan IV Carries Secret Payload Into
Space_, Vandeberg AFB, CA -- At Titan IV rocket carrying a secret
government payload was launched yesterday from this central coast
base, officials said...etc.
--
Bruce Watson (wats@scicom) Bulletin 629-49 Item 6700 Extract 75,131
------------------------------
Date: 14 Dec 92 13:53:14 GMT
From: "Allen W. Sherzer" <aws@ITI.ORG>
Subject: Titan IV Costs
Newsgroups: sci.space
In article <n116at@ofa123.fidonet.org> Wales.Larrison@ofa123.fidonet.org writes:
>...
> Titan IV $ 360 M (w/ Centaur upper stage)
> Titan IV $ 315 M (no upper stage)
Interesting number. We have two government developed launchers (Shuttle and
Titan IV) and both cost about $8,000 to $10,000 to put a pound into LEO.
Yet commercial providers only cost half to a third of that even though they
only launch smaller payloads and don't get advantages of economy of scale. Even
the now defunct Titan III (same basic design and even made on the same
production line as Titan IV) costs less than half the Titan IV.
Supporters of NLS and Spacelift I take note.
Allen
--
+---------------------------------------------------------------------------+
| Allen W. Sherzer | "A great man is one who does nothing but leaves |
| aws@iti.org | nothing undone" |
+----------------------131 DAYS TO FIRST FLIGHT OF DCX----------------------+
------------------------------
Date: 14 Dec 92 15:02:05 GMT
From: Gary Coffman <ke4zv!gary>
Subject: Titan IV Costs
Newsgroups: sci.space
In article <n116at@ofa123.fidonet.org> Wales.Larrison@ofa123.fidonet.org writes:
>
> Titan IV $ 360 M (w/ Centaur upper stage)
> Titan IV $ 315 M (no upper stage)
Do these costs include support costs at Vandenburg and Canaveral? Or
are they just purchase costs?
Gary
------------------------------
Date: 14 Dec 92 14:25:57 GMT
From: Dave Rogers <dave@rsd.dl.nec.com>
Subject: What is a VSAT?
Newsgroups: sci.space,sci.astro
In article <1992Dec11.175249.21479@athena.mit.edu>, mock@space.mit.edu (Patrick C. Mock) writes:
|>
|> Does anyone know what does VSAT (Very Small Aperature Terminal) mean
|> in the context of satellite communications?
|>
A VSAT is a C-band system which provides one-way, two-way and broadcast
capabilities for audio, video and data. Data rates up to DS-1 (1.5 M
bits per second) are available. Dishes are typically 1-3 meters in
diameter. Complete systems (one-end) sell for $6-15K. You must lease
time on a transponder from one of the many companies which do this (AT&T
Spacenet, GTE Skynet, Comstream, Vitacom).
===============================================================================
Dave Rogers
M & R Software, Inc.
Internet: dave@rsd.dl.nec.com
On contract to: NEC America, Radio Software Dept
Don't take life too seriously; you're not going to get out of it alive anyway.
------------------------------
Date: 14 Dec 92 02:59:45 GMT
From: Matthew Thomas DeLuca <matthew@oit.gatech.edu>
Subject: what the little bird told Henry
Newsgroups: sci.space
In article <1gasfqINNkpa@transfer.stratus.com> dswartz@redondo.sw.stratus.com (Dan Swartzendruber) writes:
>Look, it's pretty clear (at least to me, and going by some other recent
>postings, to other people as well) that Gary has some kind of axe to
>grind against the whole SSTO concept.
I don't agree with many of the statements that Gary has made about the SSTO
program, but it's refreshing to see someone who *doesn't* believe this will
automatically be the salvation of the space program.
--
Matthew Thomas DeLuca
Georgia Institute of Technology, Atlanta Georgia, 30332
uucp: ...!{decvax,hplabs,ncar,purdue,rutgers}!gatech!prism!matthew
Internet: matthew@prism.gatech.edu
------------------------------
Date: 14 Dec 92 13:44:23 GMT
From: Gary Coffman <ke4zv!gary>
Subject: what the little bird told Henry
Newsgroups: sci.space
In article <1gasfqINNkpa@transfer.stratus.com> dswartz@redondo.sw.stratus.com (Dan Swartzendruber) writes:
>
>Look, it's pretty clear (at least to me, and going by some other recent
>postings, to other people as well) that Gary has some kind of axe to
>grind against the whole SSTO concept.
No, I don't have an axe to grind against the SSTO *concept*, or even
against the DCX test program. What I do have an axe to grind about is
people who say, "DC-1 is the answer. Now what was the question?"
Gary
------------------------------
End of Space Digest Volume 15 : Issue 546
------------------------------