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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?

dirac_10 - 02:42pm Jun 9, 2001 EST (#4664 of 4671)

smartalix - 02:08pm Jun 9, 2001 EST (#4662 of 4663)

Seeing something and being able to affect it are two different things.

10 to 100 megawatts will do a heck of a lot of affecting. It'll turn many kilograms of steel or titanium into a gas in seconds.

Also, How can you even make a time assesment for the laser to defeat armor? Metal foil will have a different burn-through rate than ablative armor, for example. What if it takes a significant number of seconds to acheive burn-through?

Energy is conserved. The energy involved, if efficiently transferred, is ample to obliterate the warhead. And we know the energy to heat any metal to a liquid. It would probably quit working long before. And, yes, in general, it might take seconds for a warhead. Depends.

That does not even address the matter of reaction motion from ablating material, be it armor or simply warhead casing material.

Some energy sluffed off by the kinetic energy and hot parts leaving, but more energy available where that came from. And much cheaper than putting the mass into orbit. They say it costs about one thousand dollars to shoot down a katusha.

The jet of material from the laser target will instill enough random motion at the extreme distances and speeds involve to become a significant factor in beam contact time on any spot long enough to achieve burn-through.

It costs a heck of a lot more money to put mass into space than it does light. Can Russia come up with lots of clever tricks. No doubt. But N. Korea still can't even build an ICBM.

How long must a 1-MW laser be trained on a point on a piece of half-inch steel at a distance of several miles through atmosphere to burn through?

Efficiency as it passes through the atmosphere is not stated that I know of. But the range of the airplane one that will be in service in a couple of years is supposed to be many hundreds of miles.

If it can be focused to one tenth of a meter, like the existing ones at a shorter range, a 10 megawatt laser will raise a steel or titanium 1/2 inch plate to melting temperature in less than a second.

How about after it has been coated with the heat shielding required to survive atmospheric entry?

Energy is conserved. If delivered, the heat shield will vaporize.

How about after the warhead is then covered in layers of reflective and ablative material?

Cleverness in this regard, will probably be one of the things that Russia will be able to do.

But in repeating this over and over, you are missing the fact that an ICBM booster is a sitting duck, and can't be armor plated. And that the booster is the current planned target. Not that the warhead itself won't eventually be a sitting duck too.

Can you answer that question?

Looks like it.

What about if the warhead is spining/tumbling? How will the laser maintain consistent contact?

Well since we are talking about the future, not the current plan to hit the vastly easier to destroy booster, if the laser is 100 or 1000 megawatts, it won't matter. The warhead will be a cloud of gas.

Those target missiles were not only travelling far slower than an incoming warhead would re-entering the atmosphere, they weren't protected in any way.

Yeah, but they are very fast indeed. And the angular accuracy required is about the same. Not to mention that we only spent 200 millon on it. And technology is a lot better as every year goes by.

This is very good news for the technology, that is true. However, that system is still far from being ready to deploy.

About a year they say. Maybe sooner. The THEL ground based one that is. The airborne one will take a year longer.

There is a significant difference between destroying an old soviet rocket-artillery round, which is basicall

dirac_10 - 02:43pm Jun 9, 2001 EST (#4665 of 4671)

continued...

There is a significant difference between destroying an old soviet rocket-artillery round, which is basically a thin-walled metal pipe packed with explosives, and a missile nosecone,

Which, of course, is why they are planning on using the lasers against the rockets, not warheads, but hopefully, you will know that now.

I reiterate, I support this research. But even this news, as positive as it is, is a long way from fielding an operational system of any effectiveness.

Then I guess the Israelis are fools in regards to how to defend their country. They have no clue.

As far as unilateral action, I point out to you we live in a multifaceted world and we cannot isolate the extent our actions effect other nations.

Yeah, our actions are going to effect whether Saddam can destroy us by pushing a button.

We cannot simply tell Russia, "But it's only for the rogue nations!" and expect them to just nod like an idiot.

There you go again, saying that it won't work against the Saddams, but will against the Russians that had no problem with ICBM's 50 years ago. Can't have it both ways.

The very premise that an ABM system will protect us from such a rogue threat is flawed.

But it will stop Russia? Back and forth, back and forth. Make up your mind.

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