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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 - 04:16pm Jul 8, 2001 EST (#6765 of 6769)
Robert Showalter showalte@macc.wisc.edu

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 of 6769)
Robert Showalter showalte@macc.wisc.edu

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 of 6769)
Robert Showalter showalte@macc.wisc.edu

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.

It is now graciously suggested that the taxpayer pay three quarters of a billion dollars a piece for these white elephants.
Stealth Bomber, Once Scorned, Gains Fresh Backing by JAMES DAO http://www.nytimes.com/2001/06/26/national/26BOMB.html

almarst found one way, impressive mostly because it shows how easy and cheap these planes now are to detect --especially since they can take tens of hours to get to a target, because they fly so slow, and have little maneuverability.

MD 4905 almarst-2001 6/12/01 6:19pm .

MOBILE PHONE TECH MAY FOIL 'STEALTH' BOMBERS - http://www.smh.com.au/news/0106/12/world/world2.html shows one way, among many to find these "sitting ducks" -- once you know the frequency properties of the anti-reflective radar coatings they use -- information that is now widely known, and can be inferred just from design knowledge.

rshowalter - 04:23pm Jul 8, 2001 EST (#6768 of 6769)
Robert Showalter showalte@macc.wisc.edu

Now, I'll take a little time to talk about other fatal defects with the lasar weapon ideas. There are many.

This weapons sytem is a fraud -- and it is impossible for me to believe that the senior people at Boeing and the other major contactors can escape knowing it -- even if Rumsfeld, Rice, Hadley, Armitage, and others do not.

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