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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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commondata - 11:57am Nov 6, 2002 EST (# 5512 of 5515)

rshow55 11/6/02 11:29am

Are you saying that the barrier to to being able to shoot down every winged aircraft the US has, or can expect to build - to detect every submarine - and to sink every surface ship within 500 miles of land was a lack of understanding of coupled differential equations? Are you able to say more about that and do those equations relate only to guidance? I could build a 3D world in my computer. In this world I could place a target which I would have moving about randomly, erratically, evasively. My task then is to design a guided bullet to place in the world to chase and hit the target. I think I could do that using basic discrete trigonometry and I think I could do it in a weekend. Where do the differential equations fit in?

rshow55 - 02:37pm Nov 6, 2002 EST (# 5513 of 5515)
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.

commondata 11/6/02 11:57am starts with this question:

Are you saying that the barrier to to being able to shoot down every winged aircraft the US has, or can expect to build - to detect every submarine - and to sink every surface ship within 500 miles of land was a lack of understanding of coupled differential equations?

Not exactly - is is due to not knowing how to build missile controls even remotely as good as animal controls.

I want to answer the rest of your question well - in a way that might even come up to the standards science writers expect to themselves - which means an answer that is technically correct from an expert point of view, but clear enough for other readers, too. I'll have lunch, and get back to that. Before I do, here's a summary I set out a month ago that says some things compactly, with just a few additions in italics.

-------------------------------------------------------------------------------- rshowalter - 10:21pm Oct 4, 2002 BST (#334 http://talk.guardian.co.uk/WebX?14@@.ee7a163/357 includes this:

. It is now technically easy to shoot down every winged aircraft the US or any other nation has, or can expect to build - to detect every submarine - and to sink every surface ship within 500 miles of land - the technology for doing this is basic - and I see neither technical nor tactical countermeasures.

That's a judgement - let me review the reasons for that judgement.

1. Except for the cost of the information-processing controls - missiles, including actuators, are inherently simple, mass producible, and cheap. (If made with the production engineering sophistication routinely applied to cars - missiles of all kinds would be astonishingly cheap, except for the cost of controls.)

2. The accelleration capacities of missiles available forty years ago far exceed the accellerations capacities of any manned aircraft - and also exceed the accellerations of useful unmanned aircraft that have been proposed. Ranges for those missiles were tactically ample - and are higher now.

3. With guidance capacities even close to those shown by animals for millions of years - these missiles would essentially always find and destroy their targets. The approach suggested for "dogfighting model airplanes" above http://talk.guardian.co.uk/WebX?14@@.ee7a163/355 would provide guidance as good as that animals show. ( And, with the information provided, might be enough for Commondata to solve the problem he proposes in a weekend - though with more than just trig - because lines are curved, f=ma has to be integrated over time to produce the motions, and in some sense the math has to "estimate the future" well enough for control.)

4. Countermeasures now used by aircraft against missiles would be ineffective with the new approach. Trying to ourfly missiles with near-animal guidance quality would be hopeless. Counterbattery fire can't work against the new scheme. Counterbattery fire now depends on the fact that radar sources are at the same place as recievers and missile controls. Turning on radars risks operator life and system function - so that the radars are far less effective in combat than might be expected on paper. In the arrangement described for "model airplane dogfighting" radar sources are not at the same positions as recievers or missile controls. Moreover, chirpers are expendible, and can easily be made too numerous to jam.

5. Technical considerations applicable to ground-to-ship or air-to-ship missiles are analogous.

6. Submarine detection according to an analogous scheme using sound waves rather than microwaves is entirely practical - inherently inexpensive - and would give resolution of x, y, z position of undersea craft to meters. Guidance of a torpedo by sound waves would be exactly analogous to missile guidance.

Back after lunch.

manjumicha - 07:09pm Nov 6, 2002 EST (# 5514 of 5515)

Robert

Is this why some call you a Ismael?

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