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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?

lunarchick - 05:22pm Jul 17, 2001 EST (#7138 of 7145)
lunarchick@www.com

Searching for the 'Old Man'!?

rshowalter - 05:24pm Jul 17, 2001 EST (#7139 of 7145)
Robert Showalter showalte@macc.wisc.edu

In MD7107 gisterme 7/16/01 9:24pm .. gisterme cites a number of his posts that I’ve dealt with before. It seems worthwhile to review them - -- they show that the lasar weapons idea, which can seem so attractive in terms of words and a commercial artist’s rendering, falls apart when actual numbers are applied to the jobs to be done.

The citations also show something else, that people are getting familiar with. There is a “can do” spirit in the military, and among contractors, that can be admirable, when it pushes people to achieve hard but possible things. But the "can do" spirit can get in the way of fundamentals – when the answers that careful calculation yeilds are unwelcome. When it pushes people to keep betting, and wasting chances, on impossible things. ("Their's not to question why ----Their's but to do, or die . . ." )

Indeed, the citations, combined with my responses to them, that gisterme may not have understood, gives a pretty clear view of how inadequate the lasar weapon ideas the administration is betting on actually are.

There’s a “show stopper” problem, that the contractors may have overlooked -- though it is very obvious. Easier editions of the same kind of tuned reflective coatings that the lasar and mirror needs can easily be applied to both missiles and warheads. This makes missiles and warheads -b immune to lasar damage – even if optics and controls were far better than they could possibly be. http://www.phy.davidson.edu/jimn/Java/Coatings.htm The coatings are cheap and easily applied.

Even if that problem didn’t exist – the lasar weapon program is fatally flawed on several other counts

MD6407 gisterme 7/2/01 3:25pm . . . points out that the requirements for boost phase, transition phase, and rentry phase are different --- which is true enough. But the language makes an assuption -- which occurs in decisive places through the lasar weapon argument, that "if you can see it, you can hit it." The assumption, as stated, (which also occurs in very clear form in . . . MD6149 gisterme 6/27/01 3:06pm masks fatal difficulties.

I adressed that assumption in
MD6410 rshowalter 7/2/01 4:35pm ... MD6411rshowalter 7/2/01 4:42pm
MD6413 rshowalter 7/2/01 4:53pm ... MD6414 rshowalter 7/2/01 4:56pm
MD6415 rshowalter 7/2/01 5:05pm ... MD6416 rshowalter 7/2/01 5:15pm
MD6418 rshowalter 7/2/01 5:26pm

It just isn't true that "what you can see you can hit", even in controls were perfect. Not for a lasar weapon, or any other possible killing means.

And the controls aren't perfect.
MD6420 rshowalter 7/2/01 5:34pm ... MD6422 rshowalter 7/2/01 5:44pm
MD6423 rshowalter 7/2/01 5:46pm ...

rshowalter - 05:25pm Jul 17, 2001 EST (#7140 of 7145)
Robert Showalter showalte@macc.wisc.edu

Gisterme's next posting showed that these very basic points weren't understood, in a very direct way. He presented a "counterexample" -- arguing that it showed minimal lasar spreading -- that showed very great beam spreading. A spreading angle of 1.6 nanoradians was quoted - when the actual spreading rate was about ten thousand times greater than gisterme thought (for attenuation about a hundred million times greater than gisterme thought -- a serious problem for a lasar that has to burn a hole in something.)
MD6424 gisterme 7/2/01 6:03pm . . . MD6427 rshowalter 7/2/01 6:43pm
MD6428 rshowalter 7/2/01 6:51pm

rshowalter - 05:26pm Jul 17, 2001 EST (#7141 of 7145)
Robert Showalter showalte@macc.wisc.edu

The lasar weapons programs are fatally flawed because reflective coatings are so effective (and can easily shed 999/1000ths of the energy that hits them http://www.phy.davidson.edu/jimn/Java/Coatings.htm ) but even if that wasn't true, they require totally implausible optical resolution -- especially for a high power system. Perhaps the easiest, and most basic arguments against them depend on understanding what resolution is -- something nicely illustrated in nice links from Dawn on the Hubble Space Telescope http://www.astrophys.org/high_2001.html

MD6690 rshowalter 7/6/01 1:46pm ... MD6691 rshowalter 7/6/01 1:48pm

Gisterme cited examples that led a person to think that these Hubble resolution examples are somehow "pessimistic" -- that a lasar weapon could somehow maintain a better beam focus, on a powerful killer beam, than HST maintains. That's the opposite of the case.

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