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Missile Defense

Russian military leaders have expressed concern about US plans for a national missile defense system. Will defense technology be limited by possibilities for a strategic imbalance? Is this just SDI all over again?

rshowalter - 08:14am Jul 4, 2001 EST (#6531 of 6540)
Robert Showalter showalte@macc.wisc.edu

Well, gisterme, we have some disagreements, but we also have some common ground on questions of fact and reasonable probability.

Here are gisterme's words, with some emphasis added, and labeled comments, from me.

"Joking aside, your point is right, radars can't begin to approach that kind of angular resolution."

(Comment: can't begin to approach microradian accuracy -- with .1 microradian accuracy insufficient for lasar weapon aiming, along the lines the administration describes for public consumption.)

(Radars's) " best accuracy is for ranging "

(Comment: That's common ground between us, and for very low noise environments, the ranging data is as good as the ability to resolve time, which can be superb. )

"A large-antenna radar could probably give position data about as accurate as GPS

(Comment: that's a few meters resolution -- for aiming a lasar weapon, with real controls, you'd need resolution to a few millimeters, real time.)

"Information for data for a re-entry vehicle a couple of thousand miles distant. Since the BMD radar hasn't been built yet , I'm sure it was being simulated by the GPS data being transmitted from the target vehicle in the recent intercept tests.

(Comment: That's an admission. The people in Congress being told of how far along the program was weren't told that, were they? They were left to make inferences that were much more impressive than the facts, weren't they? And the information is significant for very high dollar high risk decisions, isn't it? )

" Radar guidance could get an interceptor into the "ball park" but the terminal guidance would have to be done by sensors on the interceptor."

(Comment: Common ground on what radar can and cannot do here! Not enough resolution to guide a "smart rock" to interception from ground or from big distance from orbit either, without terminal guidance on the "rock" -- But given terminal guidance, without decoys, the "smart rock" approach is at least physically possible , (as a stunt, not a tactical system). That's why the "smart rock" approach got priority twenty + years ago -- people knew that they could never get the lasar beam intensity to destroy incoming stuff at tactically significant distances, and knew they couldn't possibly aim such beams even if they had them. So now, with "smart rock" programs slow and full of problems, the administration and mic has gone back to selling a program they know can't work.)

rshowalter - 08:14am Jul 4, 2001 EST (#6532 of 6540)
Robert Showalter showalte@macc.wisc.edu

Might be a good time to search "big lie" -- this thread.

lunarchick - 08:14am Jul 4, 2001 EST (#6533 of 6540)
lunarchick@www.com

2008 could be the year of 'the alternative Olympics'.

rshowalter - 08:17am Jul 4, 2001 EST (#6534 of 6540)
Robert Showalter showalte@macc.wisc.edu

Smartalix pointed out that gisterme did not adress his technical points, and he certainly didn't -- except in ways that confirmed or reinforced them.

MD6433 smartalix 7/2/01 7:37pm

I think MD6432 is also strongly reinforced by gisterme's posting, but that the first line of MD6434 almarst-2001 7/2/01 8:04pm . . . is being subject to modification in this specific context. almarst says, quite correctly, that "By throwing enough money and time into the process, a lot of technical problems can be solved."

True enough - but some basic physical facts can't be changed.

The geometry and physics of beam dispersion is one such fact.

Conservation of energy is another fact -- How much energy is to be delivered by these lasars? - (These ultraprecision lasars.) Compared to how much is needed? (Even without dispersion. ) How do energy constraints limit what can be done?

Lasars weapons are being sold as "magic bullets" -- and they are very unmagical indeed, when you look at the details.

. . . .

"Smart rock" approaches aren't attractive either.

lunarchick - 09:03am Jul 4, 2001 EST (#6535 of 6540)
lunarchick@www.com

http://dailynews.yahoo.com/h/p/ap/20010703/wl/un_iraq_xun202.html http://dailynews.yahoo.com/fc/World/Iraq/

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