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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 - 01:30pm Jun 25, 2001 EST (#5995 of 6023)
Robert Showalter showalte@macc.wisc.edu

smartalix , you're an optics jock, aren't you (you edit a magazine that sometimes deals with lasars, as I recall?)

If I remember, the lasar "hot spot" to take out a ballistic missile on boost phase has to be on target for the order of a second (ON THE SAME SPOT) -- would you care to comment on how "easy" it is to get that resolution (say 1 cm) over the distances involved, from a moving platform (plane or satellite) shooting at a moving target?

If the distance is 100 km, isn't this a target of 10e-7 radians diameter, that is moving ? Shot at from a moving platform with some degree of vibration and "unwelcome motion" to be compensated for?

Is this degree of resolution, in your view, "easy to do?" ---

Could you give me examples where that sort of angular resolution is achieved in controls.

If you have any examples, can you give a sense of how how fast the angular motions, held to 10e-7 radian total error at all times, are?

And if anybody ever shoots such a shot, how long the setup time is?

Related question -- what if the missile, flying through the air, is rotating about its central axis? How easy would it be to tell this, or to compensate for it, if you knew it?

Another question -- how easy is it to get a lasar THAT collinear? -- (a tenth of a millionth of a radian spread angle isn't much.)

How easy would that be to do with a chemical lasar with the turbulence and heat transfer issues that apply to chemical lasars?

Me, I don't know, but these things don't sound so easy.

Armel might know something about the optics and controls, too -- he's been known to rub shoulders with astronomers and particle physicists who build hardware.

rshowalter - 01:57pm Jun 25, 2001 EST (#5996 of 6023)
Robert Showalter showalte@macc.wisc.edu

I've expressed some opinions on related issues that you can see by searching the word "shuck" on this thread.

rshowalter - 02:02pm Jun 25, 2001 EST (#5997 of 6023)
Robert Showalter showalte@macc.wisc.edu

Especially MD2489rshowalter 4/21/01 8:04pm .

We could probably solve global warming, get the world a permantently sufficient energy supply, do the technically doable things about AIDS, and do a lot of other good (and entertaining) things, for the money this administration is trying to squander on a program that could not stand up to reasonable technical crossexamination .

rshowalter - 02:45pm Jun 25, 2001 EST (#5998 of 6023)
Robert Showalter showalte@macc.wisc.edu

Old saying in shops:

" It can be truly said that you can't make what you can't measure. . . . For how would you know if you'd made it or not?

People (some at the standards bureaus of many nation states) should be able to give clear answers on how close the tolerances needed for these devices are.

From what I've seen , and what I know about how much metal changes shape spontaneously, just due to internal stresses - and how much of a nuisance this is in ultra-precise mensuration ---- I think the people talking about "easy" destruction with lasars have been missing some bases that need to be covered.

That is the sort of question (among a number of others) that ought to be checkable using unclassified information and checks that are credible in the few cases where somebody really has to check behind a valid classification barrier.

smartalix - 02:47pm Jun 25, 2001 EST (#5999 of 6023)
Anyone who denies you information considers themselves your master

I asked dirac those same questions, and he dismissed them.

The fact is that we currently do not have the neccessary skill in optics to maintain a beam that tightly over a long distance in atmosphere. In addition, the inverse-square law dictates that the farther the beam has to go, the weaker it gets.

The fact is that a boost-phase laser system ( I think I punched enough holes (pun intended) in the warhead-intercept scenario) would have to be aboard an aircraft flying along the border of the "rogue nation" to be of any utility, and we know what happens to large, slow (by definition, a large aircraft with the capacity to carry not only the laser but a power supply large enough to do the job and the crew needed to operate it would be a 747 or C-5) aircraft flying along the border of a nation that has security issues with the US.

This does not address what happens if the launch occurs under heavy cloud cover, or on a foggy day.

This also does not address a booster coated with mirrors, ablative armor, or a combination of both.

This also does not address sub-launched missiles.

If laser tech was such a great solution for missile intercept, why isn't it currently used for anti-aircraft applications?

smartalix - 02:52pm Jun 25, 2001 EST (#6000 of 6023)
Anyone who denies you information considers themselves your master

Here is an interesting article on the subject:

Pentagon Study Casts Doubt on Missile Defense Schedule
An internal Defense Department study concluded last year that testing on the national missile defense program was behind schedule and unrealistic and had suffered too many failures to justify deploying the system in 2005, a year after the Bush administration is considering deploying one.

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