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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?

gisterme - 07:24pm Jul 3, 2001 EST (#6519 of 6521)

rshowalter wrote ( rshowalter 7/2/01 6:43pm ):

Gisterme, I think the example you chose, to support your position, actually argues strongly against it.

Naa. That was 1969 technology.

Here are some more "focused" links...a bit more up to date. This link provides a basis for rating system feasibility based on current technology and also lists lots of laser applications either being considered for development or under development and some high-level explanation of how it's being done, a four-year-old study...

http://www.au.af.mil/au/awc/awcgate/cst/occppr02.htm

"...Directionality

One of the key properties of lasers is that the output beam is highly directional. Typical laser beams have a divergence of less than a milliradian,* and some systems can be designed to have sub-microradian divergences..."

"...Space-Based Ballistic Missile Defense (BMD) Weapon

Operational Concept. Already in the research phase but given a significant impetus by President Reagan’s speech on March 23, 1983, the idea of building an effective defensive shield against a massive ICBM attack included the use of space-based lasers to destroy the boosters before the reentry vehicles were released. The laser beam would be directed at the side of the booster, weakening it by heating and letting the internal pressures rupture the booster. The RVs are much harder targets because they are covered with an ablative cover capable of sustaining the heat of reentry. A large number of SBLs would be needed to provide an effective defense due to the orbital movement of the systems (likely to be deployed at about 1300 km with an orbital period of a little less than two hours119) and the large number of boosters that an adversary with ICBMs might launch.

Operational Enhancement. Destroying the boosters in the boost phase is the best solution because (1) the booster is the softest link in the chain of events that send the nuclear warheads to the target, and (2) the warheads and other debris falls back on the launching nation. An effective SBL BMD system would provide a unique, highly valuable capability to the warfighter and the nation.

Key Enabling Technologies. The discussion in the previous concept applies here. A significant amount of R&D has resulted in proof-of-concept demonstrations of the Alpha hydrogen fluoride laser, the Large Advanced Mirror Program (LAMP) and the Large Optics Demonstration Experiment (LODE) beam control system. The Ballistic Missile Defense Office (BMDO) is continuing the SBL development with the Alpha/LAMP Integration (ALI) program.

Challenges. Again, the discussion in the SBL Counterforce concept applies to this concept. The systems management challenges are significant. There must be an autonomous system that would detect the launch, activate the SBL, acquire and track the target, point the laser at the target, engage the target with the laser for a sufficient time to destroy it, and then rapidly move to the next target. The complexity and brevity of the engagement has been studied in great detail by the battle management portion of the SDIO program. Also, the laser propagation and target interaction issues are as important as the challenges of making very high-energy laser devices.

Scoring. This is perhaps the most challenging and important mission for an SBL.

Technical feasibility: 3. Technical maturity: 3. Operational enhancement: 5. Cost: 1. Total Score: 12.

And check out...

http://www.fas.org/spp/starwars/program/sbl.htm

This shows progress and integration of some of the subsystems mentioned in the above 1997 study.

rshowalter - 07:30pm Jul 3, 2001 EST (#6520 of 6521)
Robert Showalter showalte@macc.wisc.edu

Nice to have a response. Happy 4th of July, gisterme . I'll look carefully. But I'll do most of that looking tomorrow. Thanks. Out for now.

rshowalter - 07:35pm Jul 3, 2001 EST (#6521 of 6521)
Robert Showalter showalte@macc.wisc.edu

But on a first glance -- is sub microradian resolution good enough? I'm not sure it is.

I'm about to have a 2nd beer, and knock off.

But if it happens to be easy, would you have numbers (perhaps expressed in microradians) for the angular resolution of your radars? DOD folks DO use radar to do much of the aiming of these proposed anti-missile weapons, do they not?

Thanks for the reference. I'll look at it hard early.

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