ARMS-D-Request@XX.LCS.MIT.EDU.UUCP (06/11/86)
Arms-Discussion Digest Wednesday, June 11, 1986 4:50PM
Volume 6, Issue 106
Today's Topics:
In Flight Missile Control (ERCS/MX)
comment on debate tone
SDI countermeasures
Re: comment on debate tone
SDI countermeasures
SDI countermeasures
An additional SDI problem: sensor technology, added Dietz comment
----------------------------------------------------------------------
Date: Wed, 11 Jun 1986 10:46 EDT
From: LIN@XX.LCS.MIT.EDU
Subject: In Flight Missile Control (ERCS/MX)
From: Clifford Johnson <GA.CJJ at SU-Forsythe.ARPA>
what about the
Emergency Rocket Communications Systems? Surely these can receive
in-flight signals since all they've got is C3 gear?
ERCS has a tape in it that broadcasts. They stay in flight for a
relatively short time (OOM 1/2 hour) and it would be unrealistic to
assume that they could function as relays for the NCA.
------------------------------
Date: Wed, 11 Jun 1986 10:51 EDT
From: LIN@XX.LCS.MIT.EDU
Subject: comment on debate tone
From: Bruce Nevin <bnevin at cch.bbn.com>
Opinionated language--language that shoots the messenger, that rejects
as incompetent or defective those who disagree with one's beliefs or
agree with one's disbeliefs--kills intelligent debate. It is always an
expression of weakness, and deserves compassionate response, not
response in kind.
An interesting game theory question arises. Is it better to cooperate
or confront in the long run? An interesting piece in Scientific
American some years ago suggestst that a strategy of always
cooperating EXCEPT when you have been confronted (and then replying by
confronting ONCE) -- a strategy called tit-for-tat retaliation -- was
better than any other decision rule(s) determining when to cooperate
or confront. Over the long run, tit-for-tat produced better ourcomes
for both parties.
------------------------------
Date: Wed, 11 Jun 1986 11:07 EDT
From: LIN@XX.LCS.MIT.EDU
Subject: SDI countermeasures
From: Kenneth Ng <KEN at NJITCCCC>
... the Soviets
can easily counter the American SDI effort by simply clustering their
missiles close together, [so that] the SDI
satallites would be too dispersed to knock down all the missiles in
the boost phase. This method has a couple of holes in it.
First, if we find the soviets moving their missiles closer together,
we could move some (but not all) of the SDI satellites closer together.
But that increases the the total number of satellites. The whole
point of the countermeasure it to make it much more expensive for the
US to defend than for the Soviets to attack. Moving missiles closer
is cheaper than building new satellites.
Second, this simulation (if memory serves me correctly) only took into
account SDI efforts in the boost phase of the missiles. The concentration
would not effect the terminal phase SDI efforts, since the bombs still
land as dispersed as before (although there would be more bombs coming
in).
Not true. If more missiles than expected pass through boost, then
subsequent layers are VERY much more stressed, since all layers have
to be sized to handle a given level of threat.
------------------------------
Date: Wed, 11 Jun 86 11:35:28 EDT
From: Bruce Nevin <bnevin@cch.bbn.com>
Subject: Re: comment on debate tone
My point is that one may confront without responding in kind. By raising
the level of discourse or the "tone" you recontextualize your adversary's
last contribution so that the inherent paradoxes become apparent.
And opinionated language always conceals at least one paradox--
self-contradiction, if you prefer.
The only way one can maintain contradictory beliefs or disbeliefs is
to prevent communication between them. Opinionated language is a very
important smokescreen in this process of compartmentalizing one's mind.
Bruce
------------------------------
Date: Wed 11 Jun 86 13:05:32-EDT
From: Marc Vilain <MVILAIN@G.BBN.COM>
re: SDI countermeasures
Kenneth Ng proposed clustering weapon platform satellites together to
respond to Soviet missile clustering. If the satellites are in
geosynchronous orbit, this may in fact address the problem. However,
most proposals that I'm familiar with place the satellites in low Earth
orbit. This reduces power loss in lasers through refraction, and
reduces intercept times for kinetic energy weapons.
Satellites in low Earth orbit are not stationary, so in this case,
clustering weapons platforms would require increasing their density
uniformly (to avoid unclustered holes).
marc
------------------------------
Date: Wed 11 Jun 1986 12:50:21 EST
From: Paul Dietz <dietz%slb-doll.csnet@CSNET-RELAY.ARPA>
Subject: SDI countermeasures
> The theory behind this is that the SDI
>satellites would be too dispersed to knock down all the missiles in
>the boost phase. This method has a couple of holes in it.
>
>First, if we find the soviets moving their missiles closer together,
>we could move some (but not all) of the SDI satellites closer together.
>
>Second, this simulation (if memory serves me correctly) only took into
>account SDI efforts in the boost phase of the missiles. The concentration
>would not effect the terminal phase SDI efforts, since the bombs still
>land as dispersed as before (although there would be more bombs coming
>in).
This is wrong. One cannot cluster the satellites together, because they
must be in low earth orbits and are therefore not over the launch sites
most of the time. If they were all clustered together the attacker
would simply wait until they were all on the other side of the earth
before attacking. Most satellites will be out of range of any given
point at any given time; if the boosters are spread out then the
satellites have more chances to be near boosters. Note that this
clustering is far less dense than "dense pack" and would not make
nuclear attacks on the silos easier.
Second, boost phase defense is necessary to thin out the decoys/warheads
enough for the later phases to stand a chance. If boost phase defense fails
the later phases are overwhelmed.
------------------------------
From: Eugene miya <eugene@ames-aurora.arpa>
Date: 11 Jun 1986 1124-PDT (Wednesday)
Subject: An additional SDI problem: sensor technology, added Dietz comment
The view expressed within are the view of the author and not of my
agency nor of the Federal government.
------------------------------
A lot of interest has been expressed regarding the focus of the
problems of SDI: the software, in particular battle management.
Note the Science article of May 9 1986.
However, I wonder about the other components of the system.
Where there are various groups watchdogging computing, but the
more hardware oriented, EE areas such as radar have fewer opposition
elements. Recent posting on cruise missiles and the integration of
DIVAD moves me to post this
Sensor technology is one area which worries me. SDI battle management
makes certain assumptions about the abiliity to detect and identify targets.
I think that most computer people don't understand the nature of radar
to worry about the problems of `target' detection and ranging. That is
all that radar is: detection (boolean) and ranging (distance=rate times
time). A first starting references is Skolnick's text on Radar. [Dated]
Inherent problems with a ranging system include: Range and azimuth ambiguities,
difficulties with empirically determined signatures. Most people don't
seem to understand that knowing the geometry of systems are important.
Satellite images [some radar maps to be used in offensive missiles]
are not photographs (you must call them images) because
their geometry is from a linear and not a point perspective, so distance
determination for things like cruise missiles cannot be done using a
straight edge. Radar (simple) is like looking at the world using a
monochromatic spot light from the point where you are looking: you don't
get shadows (an important distance cue). Note: I have not talked about
clutter, or noise (ever wonder how high speed jets detect jets from
ground objects, or how AWACS which points down get insignificant ground
objects cleared?).
While there exist solutions, all of them involve tradeoffs in complexity,
cost, and new emergent problems. Solutions in Doppler systems,
phased arrays, stereo transmit/receive systems, but just the inherent
simplicity of the concept and the over-generalization of use worries me.
This is a case where "high-level language" solutions may not be
high-enough.
Only for Arms-d: [Peter you can remove this for risks]:
Paul Dietz noted for nuclear winter:
> It should be noted that a *mild* nuclear winter might not be all that bad.
> An article in a recent Nature shows results of an ecological simulation
> of a grassland ecology. Mild cooling after a nuclear war might
> actually *raise* yields in these ecosystems, because they are water
> limited, not sunlight limited, and cooling reduces transpiration loses.
<Sarcasm on, take the argument to the logical extreme>
Oh, let's induce a *mild* one then! We could start it in non-populated
areas. Meteorologists always wanted to do weather modification experiments.
Arms control types can argue their points with bombs going off in the
background (like they used Chernobyl).
<Sarcasm off>
In actually, you "sound" like some of the early companies promoting the
advantages of radiation, DDT, and other existing problems. While
I am not promoting radical environmentalism, I do think we have to
plan planetary scale experiments carefully.
From the Rock of Ages Home for Retired Hackers:
--eugene miya
NASA Ames Research Center
eugene@ames-aurora.ARPA
"You trust the `reply' command with all those different mailers out there?"
{hplabs,hao,dual,ihnp4,decwrl,allegra,tektronix,menlo70}!ames!aurora!eugene
------------------------------
End of Arms-Discussion Digest
*****************************