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Missile Defense

Nazi engineer and Disney space advisor Wernher Von Braun helped give us rocket science. Today, the legacy of military aeronautics has many manifestations from SDI to advanced ballistic missiles. Now there is a controversial push for a new missile defense system. What will be the role of missile defense in the new geopolitical climate and in the new scientific era?

queen108 - 12:19am Dec 3, 2000 EST (#515 of 525)
See simplicity in the complicated.

ulterior motive

Yeah, but on whose part?

vic.hernandez - 09:03am Dec 4, 2000 EST (#516 of 525)

Now that testing shows we can get within a couple of tens of yards fairly consistently, perhaps it is time to brush off the Mk54, or is it the W54, design, update it and plan on arming the interceptor with it. With a 20 to 50 ton yield, it should give a large enough kill radius to make the system work.

Why are we stuck on making a pure kinetic kill now? A good goal to shoot for, but not totally necessary to have a reliable system.

rshowalter - 06:20pm Dec 4, 2000 EST (#517 of 525)
Robert Showalter showalte@macc.wisc.edu

There are good reasons to use explosives, rather than rely on "kinetic kills", in lots of artillery applications. A few pounds, or tens of pounds of conventional explosives might make a deal of difference, as well.

Note that both distance and TIME have to be well in bounds -- does the missle killing weapon know EXACTLY when maximum proximity time will be? At the relative speeds involved, it has to.

lunarchick - 05:17pm Dec 7, 2000 EST (#518 of 525)

On the bigger question of international arms control agreements, the confusion is palpable. Mr Putin has offered deep cuts in Russia's nuclear weapons arsenal - but only if the US drops plans to deploy a new national missile defence (NMD) system known as "son of Star Wars".

This proposal has merely added to American embarrassment. Nobody can say if and when NMD will go ahead. Mr Putin is left looking like a responsible and serious international leader while the US looks… well, embarrassed. http://www.guardian.co.uk/elsewhere/journalist/story/0,7792,408117,00.html

kalter.rauch - 08:29am Dec 10, 2000 EST (#519 of 525)
Earth vs <^> <^> <^>

rshowalter 12/4/00 6:20pm

Paradoxically, it may be easier to score a direct hit on a ballistic warhead than to compute a lethal kill zone as the interceptor approaches with a combined speed of nearly 20,000 mph......?!?!?

rshowalter - 01:02pm Dec 10, 2000 EST (#520 of 525)
Robert Showalter showalte@macc.wisc.edu

If that's true, the control folks are in big trouble - that happens when you assume that a substantial arc length of a hyperbolic or parabolic path is a straight line AND both trajectories are on EXACTLY the same "ARC LENTH AS LINE" - then - if you're "in line" you don't need to time so well.

Fat chance.

But, for the scales (of 10ths of meters) that you really have to worry about, on radii of curvature of the order of earth radius, and in the real case where the trajectories are not collinear, you HAVE TO KNOW WHAT TIME IT IS, AND TO DO YOUR ARITHMETIC, ODDS ARE YOU NEED NANOSECOND PRECISION AND ACCURACY. And your angular measurement have to be dead on, too.

In addition, the math has to be right (and now it isn't.)

This for weapons propelled initially by rockets which (on the scales that matter) shake like hell, so that feedback from actuators has to be GOOD.

To hit a stationary ground target (setting air turbulence aside) is a relative piece of cake, even if you had to resolve to meters. During the ballistic phase, things are smooth, and there is plenty of time. The ABM job is out of comparison worse, and in spite of a lot of tall promises, and standards for "testing" that are quite unrealistic, things don't work well, despite hard effort from good contractors. For a reason.

My favorite book review starts

"The sad truth about this sorry book is that it should never have been written."

Anybody with security clearance, doing fair scoring, could say much the same for the ABM program.

rshowalter - 01:03pm Dec 10, 2000 EST (#521 of 525)
Robert Showalter showalte@macc.wisc.edu

Prohibition of nuclear weapons is a much more realistic bet.

lunarchick - 06:55pm Dec 13, 2000 EST (#522 of 525)

The first study of its kind has found thatmore than half of all non-lethal guns are so wildly inaccurate that they usually miss people-sized targets.

rshowalter - 11:06pm Dec 13, 2000 EST (#523 of 525)
Robert Showalter showalte@macc.wisc.edu

And the non-lethal guns have been in production a long time -- and were constructed under relatively "open" circumstances. If things had been more deeply classified, odds of mistakes would have been much worse.

People who think that "status and reliablility go up as classification status goes up" have it radically wrong.

If competent, independent engineers, with the powers of CPAs, went in and looked at Star Wars stuff, you'd see messes, on top of messes, all protected (and their funding protected) by layers of classification.

What do these people have to hide? -- maybe, multiple generations of deception, built to conceal a massive fact - the hardware doesn't work, never had any reasonably chance of working, and has no reasonable chance of working anytime in the forseeable future. The computational and control tasks to be done are orders of magnitude harder than anything anybody can now do.

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