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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?

eurocore - 07:11pm Mar 29, 2001 EST (#1726 of 1732)

Rshowalter - I'm not sure jiving will work. The mass of the rocket seems too large that the time delay via a targeting laser is not sufficient to keep the laser moving across the surface fast enough. But my estimate calcs could be wrong!

>The heat capacity of steel is relatively low, >>but just a thin layer of material on the >>outside of a potential future ICBM (carbon >>composite), would make the energy required to >>destroy the missile quite extravangent.

That's a wild guess. We are assuming our >scientists are better than the North Korean >ones. Lots of ways of defeating the mirror >coating issue.

Not that wild - most ceramics take huge heating thousands of degrees C, and we have that technology now.

(Several times more than CERN, for example, >uses). If the missile split into smaller >warheads, with faster sideways accelerations, >the beam radius generated would have increase >and the power correspondingly.

Like I said, the dern thing is traveling 20,000 >miles/hr. Material objects don't accelerate much >in the time it takes light to make the round >trip. It would take a brand new kind of > acceleration device.

The max. acceleration would have to be larger than I thought (see previous post), but at some engine-mass ratio, it would be impossible to target any point for greater than a certain period with a certain laser radius.

>I'd be very interested if an economically >>feasible laser plan could be created to prevent >>relatively large numbers of (slightly altered) >>ICBMs arriving at there targets. I'd be >>surprised (currently), if one missile was shot >>down given the above analysis.

Are you innocent of the fact that we sold such a >thing to Israel a few months ago? That would >explain some things.

This critter, built with chump change, will >shoot down a katusha rocket at 10 km. now. Right >now. 100 km. is a piece of cake.

Yes I was 'innocent' (ignorant?) of this fact.

And this is what we know about. Entertain the >idea that we do not tell the world the details >of our secret weapons. Entert

I assume anything sold to Israel must be old hat unless the US military are feeling particularly generous.

However I do remember the terribly effective Patroit missile sale before the Gulf War to Israel, so I like to see demonstrations (or reassurance from someone who knows - I'm happy to take your word on it) before I believe the effectiveness of new weapons!

Best Wishes,

Tom

rshowalter - 07:19pm Mar 29, 2001 EST (#1727 of 1732)
Robert Showalter showalte@macc.wisc.edu

The Patriot effectiveness, as you may remember, was praised to the sky for a while, and made hearts beat with pride -- but it turned out the Patriots never hit anything.

The Israelis will lie for us.

So here we have data points on how our sociotechnical system works -- and based on the judgement of George W. Bush and his hand picked men, we should feel confident?

I repeat what I said in 1724, 1725.

rshowalter - 07:22pm Mar 29, 2001 EST (#1728 of 1732)
Robert Showalter showalte@macc.wisc.edu

eurocore 3/29/01 7:11pm

you jive the warhead, which is light -- and even just a little accelleration, from something other than gravity, and the hyperbolic ballistic calculations are GONE !

rshowalter - 07:26pm Mar 29, 2001 EST (#1729 of 1732)
Robert Showalter showalte@macc.wisc.edu

Recall that the accelleration from the earth is 1 g -- .01 g, perpendicular to path, for a short time, throws things out A LOT --- HOW MANY DATA POINTS IS THE RADAR TAKING ON EACH WARHEAD, ANYWAY?

eurocore - 07:30pm Mar 29, 2001 EST (#1730 of 1732)

Rshowalter

"you jive the warhead, which is light -- and even just a little accelleration, from something other than gravity, and the hyperbolic ballistic calculations are GONE !"

Surely they don't need to hit the warhead? The fuel tanks, which are not easily movable, are the probably targets, I'd assume...

rshowalter - 07:31pm Mar 29, 2001 EST (#1731 of 1732)
Robert Showalter showalte@macc.wisc.edu

"STUPID QUESTION"

How, for real field use, do they calibrate their radars, anyway? Off satellites? Well maybe -- do they know positions well enough so that, by statistical means, they can focus things down to the resolution they actually need?

Not as a one-off stunt -- but as something done routinely, on a lot of components, in the dirty world, with people you can actually get, and the attention they can be held to after YEARS in a meticulous, boring, and thankless job?

rshowalter - 07:33pm Mar 29, 2001 EST (#1732 of 1732)
Robert Showalter showalte@macc.wisc.edu

Wouldn't it be cheaper to talk to the Koreans, and either talk to, or invade and conquer, the Iraqis, and get nuclear missiles DOWN?

Our nuclear missiles, and the Russian stuff too, is horifically obsolete, and NOT well controlled, in the internet environment.

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