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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 - 01:26pm Jun 9, 2001 EST (#4660 of 4671)

Some video and photos of the lasers shooting down rockets.

http://www.trw.com/news/kits/kits_thel.asp

dirac_10 - 01:52pm Jun 9, 2001 EST (#4661 of 4671)

Tom Romesser, TRW vice president and deputy general manager of laser programs, said the Katyusha's solid rocket motor provides 2-3 sec. of thrust enabling the vehicle to typically achieve an initial launch velocity of about a kilometer per second.

PROGRAM OFFICIALS have aimed at concentrating the energy of the laser beam on the warhead of the rocket. "The Katyushas are a 122-mm.-dia. rocket," Romesser said. "Our objective is to focus our energy so that it impacts the rocket and we deposit all of our energy on the rocket."

So... they can focus it to less than one tenth of a meter on a target traveling one km/sec. (Granted, only a few kilometers away.)

And can apparantly focus it on the warhead itself, and blow it up. Not the much easier rocket that doesn't burn long enough.

With a cheap portable existing system.

smartalix - 02:08pm Jun 9, 2001 EST (#4662 of 4671)
Anyone who denies you information considers themselves your master

Dirac,

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

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?

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

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? How about after it has been coated with the heat shielding required to survive atmospheric entry? How about after the warhead is then covered in layers of reflective and ablative material?

Can you answer that question?

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

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.

From the TRW press release from your link:

In a series of two-rocket salvo tests conducted August 28 and September 22 in the rolling, high desert of the Army’s White Sands Missile Range, N.M., the THEL/ACTD did twice what no other air defense system has ever been designed to do: detect, track and destroy multiple Katyushas in a single engagement.

This is very good news for the technology, that is true. However, that system is still far from being ready to deploy. 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, especially if it has been prepared to deal with the threat.

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.

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

All of our actions, especially those that directly affect the national security of other countries on this planet, will always have global effects, all which must be considered before taking that action.

The very premise that an ABM system will protect us from such a rogue threat is flawed. There are many other cheaper, more secure, and more effective ways of striking with a couple of nukes (the described threat scenario) at American cities than the highly complex and expensive ICBM. That is the primary reason I oppose deployment. It will not defend us from the threat we are told it will save us from.

dirac_10 - 02:12pm Jun 9, 2001 EST (#4663 of 4671)

MIRACL (Mid Infra-Red Advanced Chemical Laser) a closed loop 2.2 MW DF (Deuteurium Fluoride) laser operating at 3,800 nm at the White Sands Missile Range, New Mexico. Built by TRW for the Navy in the mid-1970s. Combined with the Skylite beam steering device, was fired successfully in 1989 in a test to attempt to intercept high-speed aerial targets. It reportedly forced down a Vandal supersonic missile simulating a sea-launched cruise missile at a range "representative of a real tactical scenario". In December 1997 it was fired at a satellite to assess the threat of anti-satellite (ASAT) weapons. Civilian uses for this laser are part of project HELLO - High-Energy Laser Light Opportunity. (see Popular Mechanics, October 1994)

Let's see now, that's 2.2 megawatts 20 years ago. Gotta' be more now.

To put it into perspective, a typical power plant is 200 megawatts.

You deliver that much energy to a warhead, and it's outta' here.

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