Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V16_6/V16NO622.TXT

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Date: Tue, 25 May 93 05:08:40
From: Space Digest maintainer <[e-mail]>
Reply-To: [e-mail]
Subject: Space Digest V16 #622
To: Space Digest Readers
Precedence: bulk


Space Digest                Tue, 25 May 93       Volume 16 : Issue 622

Today's Topics:
                      About the mercury program
                   DC-X test soon?, also DC Article
            ELEVEN G-forces during atmospheric reentry???
                  Hey Sherz! (For real!) Cost of LEO
            How do the Soviets retrieve boken satellites?
                Interesting DC-X paper I cama accross.
       Neil's words - an analysis (was Re: Neil's first words)
                    Soyuz and Shuttle Comparisons
                 Space Marketing would be wonderfull.
              Update of SSTO language for Authorization
            white paper specifying the DC-X followon: SX-2

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----------------------------------------------------------------------

Date: Mon, 24 May 1993 16:50:42 GMT
From: Gary Coffman <ke4zv!gary>
Subject: About the mercury program
Newsgroups: sci.space

In article <[e-mail]> Leigh Palmer <[e-mail]> writes:
>In article <[e-mail]> Gary Coffman,
>[e-mail] writes:
>>I think it's wrong to blame the astronaut for this failure, at least not
>>totally. Instead the PI screwed up in mechanical design. A look at his
>>3 year old's Jack in the Box would have showed him how to make a box with
>>a hand crank that even the clumsiest little vandal couldn't easily break.
>
>A real apologist for the astronaut!
>
>Do you suppose he broke the handle in rehearsal? Is it possible he didn't
>rehearse? Would it have been wise for him to have rehearsed?

It would have been wisest to design the box so it could cope with ordinary
forces. It's not like the astronaut was exerting all his strength here.
Simple prudence says that laboratory equipment should be designed to withstand
ordinary handling unless there is some reason *critical to the experiment*
for making it extraordinarily delicate. There's no indication that that was
the case here. As to a rehearsal, I suspect that if the PI had even bothered
to have a grad student turn the crank, he would have found out how faulty
his design was long before an astronaut became involved. Remember, it wasn't
the crank that broke, it was the box, dumping it's contents into the capsule.
That capule was going to experience 12 G deacceleration on landing. Care
to speculate on the fate of that delicate box during re-entry if the astronaut
had been *real* gingerly in turning the crank?

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     |                     |

------------------------------

Date: Mon, 24 May 1993 18:23:11 GMT
From: Mike Butts <[e-mail]>
Subject: DC-X test soon?, also DC Article
Newsgroups: sci.space

Forgive my late return to this group, but I infer that a real DC-X test is
really impending.  Am I right?  What are the details?

Also there is a very good summary article including diagrams and specifics
in the current issue of Analog Science Fact/Science Fiction.

Thanks, and Go DC-X!
--
Mike Butts   [e-mail]    Research Engineering Mgr.    503-685-1302
Quickturn Systems, Inc.,  8005 SW Boeckman Road, Wilsonville, Oregon  97070
My opinions are my own, and aren't necessarily shared by Quickturn Systems.

------------------------------

Date: Mon, 24 May 1993 17:19:05 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: ELEVEN G-forces during atmospheric reentry???
Newsgroups: sci.space

In <[e-mail]> [e-mail] (Claudio Oliveira Egalon) writes:

>A friend of mine has written that  Gus Grinson, during his
>suborbital flight of the Mercury program, was subjected to
>acelerations from 0 to ELEVEN g's, within 32 seconds,  when
>he was reentring the atmosphere!!! Although I can not recall
>the phisiological tolerance to g-forces 11 g's seems darn too
> high for me. Most likely it is well above the value that
>anyone can tolerate. So my questions are:

>1) What is the g interval that a human being can tolerate and

Somewhere in the neighborhood of 6-9g continuous is about all a
typical pilot can be expected to take for prolonged periods and remain
functional (i.e., able to continue ACM).  At 9+ g, GLC onset tends to be
close to instantaneous (when it happens).  At lower g, pilots will
experience 'wash-out' of vision (loss of color) and/or tunnel vision
prior to loss of consciousness.  This is why aircraft like the F-16
are more hazardous to fly at high g; the pilot will receive few or no
cues that it's time to 'unload' prior to losing consciousness.

Note that this is all assuming that the individual is basically in a
reclined sitting position with a g-suit.  Other positions may allow
greater or lesser g-tolerance; more reclined would cause it to go up,
more upright or taking 'negative g' will cause it to go down.

>2) What was the maximum acceleration that a Mercury
>astronaut was subjected to.

I don't know for sure, but I understand that peaks were fairly high,
so g-forces in the 'teens don't sound particularly unreasonable for
short periods of time.  It is possible to take what seems like
incredibly high g so long as the duration is short.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

------------------------------

Date: Mon, 24 May 1993 16:41:54 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: Hey Sherz! (For real!) Cost of LEO
Newsgroups: sci.space

In <1tpt1o$[e-mail]> [e-mail] (Ken Hayashida) writes:

>Mr. Sherzer originally posted that he felt
>>As a rough guess I would say that in 10 years Shuttle has delivered
>>to LEO about as much as Saturn V did in 4 years.

>I have been criticized for not making an appropriate comparison.
>I would remind you that I retracted my statement about STS delivering
>the most mass to orbit.  I have not heard Mr. Sherzer retract his
>statement made above.

Why should he retract it if it is true?

>I am attempting to ascertain the validity of this statement in
>an objective manner.  A basic tenet of the scientific method
>is to approach issues as objectively as possible.  Several of
>you appear unprepared to drop your subjectivity in this
>analysis.

Let me get this straight.  You're a doctor criticizing engineers over
their objectivity when looking at the engineering of various vehicles?

>I have defined how I will be determining the amount
>of material the Saturn V delivered to LEO and
>the amount of material which the Space Transportation
>System has delivered to LEO.  Inclusion of the S-IV-B stage
>is reasonable and important.  The upper stage of the Saturn
>V was clearly delivered to LEO by the Saturn V vehicle.
>Josh Hopkins corrected my inclusion of the escape tower in
>the Saturn calculation.  I would point out that in the
>grand scheme of things, the tower's mass would probably
>cause a minimal change in the total mass which the Saturn
>program delivered to Low Earth orbit.

>Inclusion of the orbiter in the STS calculation is clearly

>indicated because the orbiter reaches LEO.  Both reach
>orbit.  Both are relevant in order to ascertain the validity of
>Mr. Sherzer's statement.

Neither is relevant.  Delivery of *the vehicle* to LEO is only
reasonably countable if the vehicle you are talking about is intended
to go higher from there.  Otherwise, you are not talking about
'payload', per se, except in the sense that you have to keep boosting
the whole Shuttle as a 'lab' because you keep bringing it back down
for no good reason.

One can always predetermine the 'winner' by selectively choosing an
appropriate measure, whether that measure is meaningful or not.

>In the future, I hope more people will publish on sci.space
>their own sources, references, and calculations in order that
>all may understand the way they have reached conclusions.

>I also find it strange that so many shuttle critics would snub
>the issue of mass return while attempting to tout the
>importance of space commercialization.  The true
>commercialization of space will be when travel is to and
>from LEO.  Shuttle is currently the best vehicle at achieving
>this mission.

How much of the mass that the Shuttle has returned has been stuff that
needed to be returned to fulfill mission?  It returns *itself* -- we
would be better served to leave the 'lab' on orbit.  It returned the
LDEF; that was sort of necessary for study.  There is no important
return requirement for most things, and much of what else needs to be
returned is more economically brought back by simply sealing it in a
can and dropping it.

>Shuttle critics choose to downplay and underestimate the
>importance and difficulty in the historic missions which the
>orbiter has flown to service and recover multi-million dollar
>satillites.  While some may argue the economics of these
>achievements, they usually choose to ignore the difficulty in
>flying these missions.  They also choose to belittle the
>demonstrated capabilities of the orbiter to successfully
>accomplish these important missions.

In another note, you criticize a comment Pat made because he couldn't
understand the technical difficulty or degree of complexity of
developing a new medical treatment, yet here you are, a doctor telling
engineers that you understand their field better than they do.

>Mr. Spencer, if you would like to start publishing your own
>calculations supporting your views of the shuttle program,
>I'd enjoy reading them.  The challenge of poking holes in
>your or Mr. Sherzer's papers (and vice versa) should allow
>non-posters the opportunity to better assess their positions
>relative to ours.

While I don't know Henry personally, I will tell you what anyone who
has been around the net for any length of time will tell you.  If you
find yourself in substantive disagreement with Henry Spencer, you
should prepare yourself for the discovery that you are wrong.

>Mr. Sherzer, since you are such a critic of the shuttle
>program and tout the DC-Y's performance.  Please start
>to publish the vehicleUs developmental cost, payload to
>orbit, recovery time and cost, cost of manufacturing the
>vehicle, if anyone really knows.  If any of these are
>unknown, are you really that different than those who
>erroneously believed the shuttles would fly once per week?

I do know Alan personally (we used to work at the same facility down
here).  While I am of the opinion that some of his costing
measurements for Shuttle costs vice the costs of some expendables are
somewhat unfair in how they elect to measure, I would say that his
engineering is sound; particularly when compared to that of a doctor
of medicine.  One can look at the two systems (Shuttle and DC) and see
the difference immediately.  Shuttle is *designed* to require
extensive refurbishment after each and every flight and pushes its
design to the limits.  DC does not do those things.  So you tell me
what's reasonable to believe when comparing the two.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

------------------------------

Date: Mon, 24 May 1993 16:45:59 GMT
From: fred j mccall 575-3539 <[e-mail]>
Subject: How do the Soviets retrieve boken satellites?
Newsgroups: sci.space

In <[e-mail]> "William F. O'Dell" <[e-mail]> writes:

>All of this STS vs. Soyez got me wondering.
>How do the Soviets retrieve scewed up satellites?-Or do they?
>Just curious.

They don't.  It's more economical for them to deorbit the old one (or
boost it) and launch a new bird.  Even given our much higher costs to
orbit, this is usually cheaper for us, as well.

--
"Insisting on perfect safety is for people who don't have the balls to live
 in the real world."   -- Mary Shafer, NASA Ames Dryden
------------------------------------------------------------------------------
[e-mail] - I don't speak for others and they don't speak for me.

------------------------------

Date: Mon, 24 May 1993 18:38:07 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Interesting DC-X paper I cama accross.
Newsgroups: sci.space

29 April 1993

WHAT'S AL THE WORRY ABOUT A CRASH
The need for a win-win public relations strategy
by Steve Hoeser

Introduction: The SSTO/SSRT opponents have us on the defenseive and
we're letting them put us there.  I see us falling back into the
standard practice of defending our program when we should be on
the offensive.  This is a formula for disaster.

Background: The opposition first used the tactic of saying that we
couldn't build the DC-X and that it was a stunt.  But their actions
to kill it showed instead that they were deathly afraid that we
might do.  Showing that you can build some very impressing hardware
fast and cheap, took a big chunk out of the establishment's credibility.

Failing the kill technique, the opposition is now posturing to exploit
a crash.  They will not only pounce on us when we're down they will
send in a full nuclear strike.

Conclusion: It is time to take the offensive with a public relations
strategy capable of claiming victory regardless of the DC-X test.

Recommendation: The entire SSTO/SSRT support structure adopt the
position that, _breaking the DC-X is and always was part of the plan._
_This must start now_ lest we give the opposition the weapon of
plausible denial by waiting until after a crash.

Discussion: A preemptive and sustained public relations bombardment is
needed to take away the opposition's ammunition.  Key support factions
and the public at large need to clearly understand that X-Vehicle
programs break things because that is what they are supposed to do.
Most importantly, this may very well include crashing the vehicle.

* It has always been an accepted fact that the DC-X would break and
could even crash (somehow it seems that people working the program
have forgotten this).  Part of developing operations procedures is
that things break and things get fixed.  Test airplanes crash, get
repaired, and fly again.  _I can think of no more devestating a blow
to the opposition than to crash this beast, fix it and fly it again._
"We never could have done that after a command destruct!"

* X-Vehicle programs push to find the limits.  This is what saves
money ad makes the prototypes and operational vehicles work.

* We need to prepare responses for the following conditions:
-- _The vehicle breaks (minor damage)_: Well we figured it would break,
now we can find out the best ways to fix it.
-- _The vehicle crashes_: Well we planned to break it and we did a
bang-up job.  Now we'll get a chance to check out how tough the beast
really was and see if we can make her fly again.
-- _An inherent design flaw is discovered in test_: We find out from
data that under certain flight conditions there is a high probability
that the vehicle could crash.  We must identify the design problem,
determine a fix, then announce termination of the flight test program.
Its stupid to wreck the hardware when we don't have to.  Besides, it
will look a lot better in the Smithsonian's Air and Space Museum in
one piece than in a big pile.
(((Kyger comment: It's also vendication of _flight test_ as the means
of obtaining real world data, as opposed to analysis and paper
shuffling -- even if the data are negative.)))
-- _The vehicle successfully completes the entire initial test series_:
We met our initial test objectives.  We could have flown (or would have
liked to fly) more but we're out of money.  But enough is as good as a
feast and it would be little more than grandstanding to fly more..

--
+---------------------------------------------------------------------------+
| Lady Astor:   "Sir, if you were my husband I would poison your coffee!"   |
| W. Churchill: "Madam, if you were my wife, I would drink it."             |
+----------------------23 DAYS TO FIRST FLIGHT OF DCX-----------------------+

------------------------------

Date: Mon, 24 May 93 16:54:13 EDT
From: "Darryl O. Cottle" <[e-mail]>
Subject: Neil's words - an analysis (was Re: Neil's first words)

Having just seen (and heard) the clip in question yesterday afternoon
I'd like to kick in a few farthings worth.

Initially the question was "...a damn step" vs "...a big step" vs "...a
giant step" (the correct version).  Thence we proceeded on to whether
Neil said "for a man" or "for man."

One poster stated that the "a" WAS said but too softly for the radio
equipment to pick it up.  This explanation doesn't wash for reasons
I'll lay out in a moment.

If my memory serves Neil himself was the FIRST one to say that he had
not said what he had intended to say. (As worded the implication was
"one small step for man(kind) a giant leap for mankind" which, of
course, is redundant!)

As to the question of it being more correct to say "a giant leap for
(a) man - a small step for mankind" that doesn't wash either.  Our
species evolved over how many thousands of millenia?  The number
keeps getting bigger all the time.  Yet all this one man had to do
was step off the LEM's ladder down to the surface.  (It was more than
just a small step if your legs were short!) Contrast this with all
that had to happen before a member of our species was ABLE to be in
a position to take that "small" step and it truly is a GIANT leap.

Now to the question of whether or not Neil said "for a man."  I'm
not a speech pathologist (far from it) but I work with international
students and have often had to explain nuances of pronunciation to
people whose first language isn't English (or even 2nd or 3rd in
some cases) and have come to appreciate the various positions the
jaw, lips, and tongue have to be in to make certain sounds.

Anybody can try this themselves if they doubt my conclusions.  We
tend to miss the significance of this matter when "reading" quotes
once we get past the point of "mouthing" the words.

To follow the word "for" with the word "man" very little repositioning
of anything except the lips is required.  To say the word "a"
in the middle, however, requires a shift of the jaw, tongue, and
lips all three.  True this doesn't take much time but it DOES take
a perceptible pause for it to happen.  We say "for", perform the
shift, say "a", then perform another shift to say "man."  As I
said at the top, I saw (and heard) the clip again yesterday after-
noon (on the discovery channel's "Amazing Space") and I'll now
reproduce my interpretation of what I heard.

"That's one small step" <pause> "for man" <pause> "a giant leap for
mankind."

Now I'll repeat it as the poster who claimed "a" WAS said would have
us believe it happened, using CAPS to indicate volume sufficiently
high to be picked up with Neil's radio.

"THAT'S ONE SMALL STEP" <pause> "FORaMAN" <pause> "A GIANT LEAP FOR
MANKIND."                        ^^^^^^^

If this radio had been like a voice actuated recorder I could see
where the word "a" might have been too low to be picked up - but
this was a "real time" transmission.  If Neil had paused long
enough to shift his tongue, jaw, and lips to say "a" and then
shifted them again to say "man" then the interval between the
words would have been noticeably longer (not vastly longer but
DEFINITELY perceptible).  Try it yourself.  You can come closer
to closing the gap if you say "uh" rather than "a" but still the
gap would be there!

I propose that Neil didn't say "for a man" because the record of
the statement doesn't provide a sufficient time interval for it
to have been said.  Further I believe him when HE said that he
didn't say what he intended to say.  NASA is responsible for the
confusion since they decided to make the "official" record say
                                          ^^^^^^^^
what Neil MEANT to say, rather than what he actually said.

You've perhaps heard the quote "I know you believe that you
understand what you think I said. However I'm not sure if you
are aware that what you think you heard is not what I meant!"
Seems applicable in this situation.  The quote as it was meant to
be said is really great and I honor the man who meant to say it!

QED
                                     The lurker at the threshhold.

+- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- -+
|     (snail mail)         |"I don't know what I'm doin'!|   (voice)    |
|*Darryl O. (Doc) Cottle   |  If I ever DO figure it out,| 606-257-7577 |
| Agricultural Economics   |   I'll prob'ly go HIDE!!"   |     or       |
|*431 Ag Engineering Bldg 2|   "Brother" Dave Gardner    | 606-231-6675 |
| University of Kentucky   |-----------------------------|--------------|
|*Lexington, KY 40546-0276 | "Where were you born?"                     |
| - - - - - <> - - - - - - | "Oh, are you one of them astrology dudes?  |
|* = short form of address |  I'm a Cancer with a bad moon risin'!"     |
|--------------------------|         Cheech Marin (Born in East L.A.)   |
|    (electronic)          +--------------------------------------------+
| [e-mail]    or else try    [e-mail]          |
+- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- --- -+

------------------------------

Date: Mon, 24 May 1993 17:46:20 GMT
From: Frank Crary <[e-mail]>
Subject: Soyuz and Shuttle Comparisons
Newsgroups: sci.space

In article <[e-mail]> [e-mail] (Chris Jones) writes:
>>               The Soyuz is launched on the Soyuz (the
>>Soviet press named launch vehicles after the first spacecraft
>>they launched...) aka SL-4 aka "Type A-3" launch vehicle.

>The Soyuz was not the first vehicle launched by this booster.  The two Voskhod
>flights used this launcher, as did their (and Soyuuzes) unmanned precursors
>flown under the Kosmos banner.  I don't know what was the first use.

I think the Voskhods used the SL-2, but I suspect the Soviet press
criteria wasn't very exact: They probably used the first launch
they reported (Kosmos imssions usually aren't) not the real
first launch...


                                                    Frank Crary
                                                    CU Boulder

------------------------------

Date: 24 May 93 18:16:13 GMT
From: Jane Beckman <[e-mail]>
Subject: Space Marketing would be wonderfull.
Newsgroups: sci.environment,misc.consumers,sci.astro,talk.environment,talk.politics.space,sci.space,rec.backcountry,misc.rural,misc.headlines

Of course, I doubt that folks have allowed that if they can
put a billboard in space, they probably can also put a
billboard-killer in space, send up something that would turn
the orbiting advertisement into small shreds of debris.  I'm
sure you could find LOTS of people willing to donate a few
hundred dollars to such a good cause!  It could give a whole
new aspect to the concept of monkey-wrenching.

Finally, a *good* use for "star wars" technology!

Seriously, though, I think that the Perseid meteor shower
could wreck some serious havoc on the Great Sign, too.  Or any
other floating chunks of space rock that normally bombard the
earth of a regular schedule.  We're talking about fairly
fragile materials, not like tough, compact satellite
materials.
--
  Jilara   [[e-mail]]

"Every now and then, a big rock falls out of the sky, and everyone has
a *very bad* day."  --from the PBS "Dinosaurs" special.

------------------------------

Date: Mon, 24 May 1993 18:35:24 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: Update of SSTO language for Authorization
Newsgroups: sci.space,talk.politics.space

Draft Report Language
-- For Inclusion in the
FY '94 DoD Authorization Bill

Single Stage Rocket Technology (SSRT) Program

Of all the dual-use spacelift technologies currently targeted
for operation within a decade, reusable, Single Stage to Orbit
(SSTO) rockets offer the highest potential for radically
reduced costs and increased safety, reliability, and
operability. According to recent studies performed for the Air
Force and NASA, SSTO's have the potential of reducing the
operational cost of delivering payloads to low Earth orbit by
an order of magnitude, restoring U.S. competitiveness.

The Strategic Defense Initiative Organization (SDIO) is
carrying out a well-planned Advanced Technology Demonstration
(ATD) program to demonstrate the availability and cost
effectiveness of Single Stage Rocket Technology (SSRT).  The
SSRT program is structured to rapidly prototype and fly
experimental vehicles of increasing size and performance to
demonstrate the feasibility of single stage reusable rockets
one step at a time, within budget, and in a short time.

The SSRT program is important because it will provide the DoD
with a demonstrated SSTO technology option for consideration as
a next generation spacelift system.

The first ATD vehicle, the DC-X1, is on schedule and within
budget, and positive conclusive results are expected by the end
of fiscal year 1993.  The second ATD vehicle, the DC-X2,is
scheduled to begin development in fiscal year 1994.  Successful
flight testing of the DC-X1 and DC-X2 will provide the
confidence necessary to proceed into initial development of a
full-scale operational SSTO system.

The Committee is concerned that the SSRT program is only
budgeted at $5,000,000 in fiscal year 1994, and questions the
level of funding support available within SDIO for completion
of the DC-X2 ATD.  Based on the expected positive results from
the DC-X1 flight tests, and because of the significant
potential that single stage rockets promise for reduced costs
and increased reliability and operability, the SDIO is directed
to begin development of the DC-X2 in fiscal year 1994.  The
Committee also directs SDIO to evaluate the feasibility of
transitioning the SSRT program in fiscal year 1995 to
appropriate new management commensurate with its dual-use
nature, such as the Advanced Research Projects Agency (ARPA) or
the Technology Executive Officer (TEO) structure within the Air
Force, and to provide its recommendations to the Committee by
August,1993.

The Committee directs that $75,000,000 be authorized in fiscal
year 1994 for SDIO to proceed aggressively with the SSRT
program, including development and flight testing of the DC-X2
ATD.

--
+---------------------------------------------------------------------------+
| Lady Astor:   "Sir, if you were my husband I would poison your coffee!"   |
| W. Churchill: "Madam, if you were my wife, I would drink it."             |
+----------------------23 DAYS TO FIRST FLIGHT OF DCX-----------------------+

------------------------------

Date: Mon, 24 May 1993 18:37:15 GMT
From: "Allen W. Sherzer" <[e-mail]>
Subject: white paper specifying the DC-X followon: SX-2
Newsgroups: sci.space

[This is the paper I promised to post a while ago. Sorry for the delay.
  It gives some specifics of the current thinking for a DC-X followon.]
   -Allen


                     White Paper
     SX-2 Advanced Technology Demonstrator (ATD) Program
                       Col. Worden, SDIO

The Single Stage Rocket Technology (SSRT) program will begin flight
testing the DC-X vehicle this summer.  Currently, SDIO is not budgeting
funds for any other effort other than $5 million in FY94 to compllete
the DC-X flight testing.  SDIO is encouraging other DOD agencies
(ARPA and USAF), the Department of Energy (Sandia and Los Alamos
National Laboratories), NASA, or a combination of the above to support
a joint follow-on ATD program run from SDIO or another agency.  This
paper recommends a Fast Track ATD program that is well defined and for
which independent government cost and schedule estimates exist.

_SX-2 Program Definition:_ The follow-on program would build and fly
the SX-2 (Spaceplane Experimental) ATD within three years.  The SX-2
uses the same RL-10A5 engines as the DC-X with performance enhancements
provided by subcontracts with the Russian rocket engine company
Energomash.  The vehicle operates out of the same basic facilities and
uses the same ground-based crew and control center used to fly the DC-X.
Airframe construction will demonstrate the identical composites and
unit weights needed for follow-on suborbital and Single Stage to Orbit
(SSTO) vehicles.  Maximum altitude for the SX-2 is 600,000 feet providing
four to five minutes of microgravity time in space.  Like its predecessor,
the DC-X, the SX-2 will push even further toward demonstrating the
feasibility of rocket powered "aircraft-like" operations, support,
reliability and associated recurring flight costs in the only credible
way -- by doing it.  The SX-2 like the DC-X, uses oxygen and hydrogen
to support all propulsion and power needs, and offers an environmentally
benign exhaust product -- water.  With clean exhaust, manageable noise
levels and no staging debris, the SX-2 is an environmentally friendly
system that can help set the standard for all 21st century launch systems.

_Why SX-2:_ The rationale for funding the SX-2 program centers around
five military/commercial "dual use" thrusts: 1) enabling the construction
of follow-on suborbital and orbital vehicles providing vastly less
expensive commercial spacelift services and fundamentally new strategic
and tactical military capabilities, 2) assuring that the American
aerospace industry is the first to commercially exploit low cost, highly
reliable space access, 3) providing dual use technology spinoffs to the
commercial and military sectors, 4) bolstering the aerospace industrial
base by opening profitable new commercial opportunities, and 5) developing
American-Russian  cooperative ventures.

_Funding Requirements:_ The SX-2 program is envisioned as a competitive
procurement in which three prime airframe contractors have expressed an
interest: Lockheed, McDonnell Douglas and Rockwell International.  Total
program cost as estimated by both the government and the McDonnell Douglas
industry wide team is $450 million.  The fiscal year breakout is $75,
$185, $180 and $10 million through FY94 through FY97 respectively.  The
first year of design will focus on reducing the program cost as far as
possible towards a self-imposed $300 million Design-to-Cost goal.  Just
as completing the DC-X significantly reduced the cost and uncertainty of
proceeding with the SX-2, the SX-2 program will provide accurate, low risk
estimates of the cost of proceeding with follow-on suborbital and orbital
vehicles.

NEXT PAGE...

ADDENDUM
Rationale For SX-2 Program

A successful SX-2 program will directly enable a family of military,
civil and commercial derived vehicles.  From cheap suborbital rockets
identical to the SX-2 for university and commercial research, to inter-
continental ballistic transport vehicles able to deliver cargo globally
within minutes, to tommorrow's SSTO launch vehicles, a successful SX-2
program will conclusively show that such vehicles can be built and allow
credible estimates of their operating costs and reliabilities.  Moreover,
if the SX-2 flies as cheaply as the DC-X is designed to operate today,
by the turn of the century follow-on vehicles could begin reducing
operating costs by up to an order of magnitude over the $10 billion the
U.S. spends annually on space launch.  Even highly subsidized foreign
launch vehicles can't compete with such radicaly reduced operating costs.
Beyond space launch, such aerospace vehicles can provide an important
complement to tommorrow's military force structure.  Their ability to
respond globally from central CONUS with the speed of an ICBM and the
flexibility of a modern aircraft could form an important pillar of the
Air Force's emerging 21st century "Global Reach -- Global Power"
strategy.

As far back as the 1986 National Commission on Space, and every national
assessment since, the need for fundamentally lower launch costs has
consistently been cited as the seminal barrier to the growth of commercial
space enterprises.  The SX-2 takes a measured step which will quantify
the magnitude of potential cost savings and develop a host of commercially
useful technologies ready for new dual use military and commercial
application.

Technology transfer to the commercial sector can be expedited by a
focused program to transition key technologies to American and Russian
commercial enterprises.  For example, light weight composite materials
usable from cryogenic to room temperatures have potential applications
ranging from comercial aviation to the automotive industry; high
temperature superalloys and composites can enable more efficient engines
of all kinds; and hydrogen generation and handling equipment, fuel cells
and power units will take a significant step towards a 21st century
economy based on hydrogen, electric cars and pollution free hydrogen
fueled automobiles.  Building the SX-2 in conjunction with an aggressive
technology transfer program will allow America to beat the Japanese at
their own game -- be the first to spin-off state-of-the-art (but off-the-
shelf) technogies to commercial applications.

Beyond technology spin-off, the SX-2 provides a focus for high technology
American-Russian cooperation and will bolster the declining American
aerospace industry with contracted work in many of the 50 states, but
focused in Alabama, California, Colorado, Florida, Missouri and New Mexico.
With Russian provided propulsion enhancements it's likely the SX-2 will
eventually break the X-15 speed record of Mach 6.7.  Once its initial
flight test objectives are achieved, the SX-2 can be used for many
experiments and high speed technology development for the next century.
Low cost, routine access to the hypersonic flight regime can expedite
high speed technology development.  Experiments flown on the SX-2 can
benefit many key technologies including base burning, actively cooled
structures, heat pipes, high temperature materials, durable flight
controls, hot structures, advanced cryogenic tanks, slush hydrogen,
triple point oxygen, advanced avionics and rocket augmented flight.
The vision enabled by the SX-2 program can provide a focus for America's
youth encouraging higher education and fundamentally new commercial
industries on America's space frontier.  But the first step unquestionalbly
must be development and flight of a proof-of-concept demonstrator like
the SX-2..

--
+---------------------------------------------------------------------------+
| Lady Astor:   "Sir, if you were my husband I would poison your coffee!"   |
| W. Churchill: "Madam, if you were my wife, I would drink it."             |
+----------------------23 DAYS TO FIRST FLIGHT OF DCX-----------------------+

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End of Space Digest Volume 16 : Issue 622
------------------------------