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Missile Defense

Technology has always found its greatest consumer in a nation's war and defense efforts. Since the last attempts at a "Star Wars" defense system, has technology changed considerably enough to make the latest Missile Defense initiatives more successful? Can such an application of science be successful? Is a militarized space inevitable, necessary or impossible?

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rshow55 - 12:00pm Sep 24, 2002 EST (# 4508 of 4511)
Can we do a better job of finding truth? YES. Click "rshow55" for some things Lchic and I have done and worked for on this thread.

The Queen of England has a duty to warn. Senior officers have a duty to warn. 3 Retired Generals Warn of Peril in Attacking Iraq Without Backing of U.N. by Eric Schmitt http://www.nytimes.com/2002/09/24/international/middleeast/24IRAQ.html and I have a duty to warn, too.

Sometimes, the question "what did they know, and when did they know it" is important. There's been additional discussion and progress since these postings -- referenced in MD 84 rshow55 3/2/02 11:52am - - but these postings, I believe, bear on issues of technical function important to this thread, and connected to questions of how much we should trust this administration. On matters of technical judgement on which moral questions also depend. Here are postings that deal with facts and relations, that have not been successfully disputed - that bear on our risks, and decisions that leaders of the United States can safely and responsibly make.

rshow55 - 12:03pm Sep 24, 2002 EST (# 4509 of 4511)
Can we do a better job of finding truth? YES. Click "rshow55" for some things Lchic and I have done and worked for on this thread.

rshowalter - 04:16pm Jul 8, 2001 EST (#6765

It is technically easy to make missiles and warheads immune to lasar weapons -- even if the lasar weapons did achieve a chain of miracles related to optical resolution and control.

See: Reflective Coatings http://www.phy.davidson.edu/jimn/Java/Coatings.htm

" Utilizing the phenomena of constructive and destructive interference, engineers may create a multitude of thin-film coatings with different reflective properties. . . . .

" For applications that require mirrors with very high reflectance (such as a laser mirror), several layers of coating may be used. Often, many layers of alternating indices of refraction may be used to increase the reflectance to more than 98%. In the following example, the mirror is made of alternating layers of zinc sulfide (n=2.3) and magnesium fluoride (n=1.35) film (For an excellent discussion of these and other coating methods see Fowles, Grant R. Introduction to Modern Optics. 2nd ed. Dover Publications, 1975.

The web site has a fine demo - worth checking out, that shows how VERY high refectances can be obtained for a fairly wide range of wavelengths. The demo asks you to

" Add layers and observe how the reflectance changes."

For a VERY narrow wavelength range, coatings can have VERY high reflections.

The basic technology is well understood, and coating missile parts is a CHEAP thing to do. Reflectances greater than .99 are almost certainly cheap to make for the exactly known and specific wavelength to the military lasars the US is developing. (Reflectances of .999 might be possible.) Rejection of 99% of the lasar energy is enough to make the lasar weapons entirely ineffectual, even assuming very far fetched resolution and control capabilities -- and with real capabilities, the relective shields probably wouldn't even be needed.

That makes boost phase missiles, and warheads immune to the lasar weapons under development.

Just because of reflective coating performance -- not to mention a string of other probably fatal problems.

The engineers asking for money for the program, and promising to make a contribution to US defense have to know this.

I'm at a loss, myself, to understand how this cannot be treason.

rshowalter - 04:17pm Jul 8, 2001 EST (#6766

Anyone capable of passing the undergraduate program with adequate grades from a reasonable physics school knows everything necessary to protect missiles, for very little cost. Neither the materials, nor the processes, are particularly fancy, for the levels of reflection that immunity to lasar weapons would take.

For a commercial source of reflector coatings, including some billed as "Lasar Damage Resistant" see http://www.drli.net/ http://www.drli.net/products1.htm http://www.drli.net/aboutdrli.htm http://www.drli.net/Fac&Equip.htm

rshowalter - 04:21pm Jul 8, 2001 EST (#6767

Snell's law is pretty basic. The military-industrial complex acts as if nobody but them knows it.

For that reason, they are willing to sell obsolete "stealth" aircraft that are now sitting ducks -- to any country that knows how to build very LONG wavelength radar -- (easy with WWII technology) to find roughly where the "stealth" planes will be, and also knows how to use radio illumination for indirect observation, to high resolution, to see these very slow and easy to shoot down planes.

These are very inconvenient planes, with only their "invisibility" as an advantage -- and now, they are easy to see -and the information on how to see them is obvious to anyone who knows how reflective (or antireflective) coatings work

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