Re: Anti Zeppelin systems

From: Michael S. Lorrey (
Date: Mon Jul 24 2000 - 09:57:40 MDT

John Clark wrote:
> Michael S. Lorrey <> Wrote:
> >No, decoys are supposed to be cheap.
> I thought that's what I just said but perhaps I don't write well English.

Sorry, that wasn't clear. It seemed like you were saying it was ok if they cost
as much..

> >If they cost as much as the real thing, you might as well stick some nukes on them.
> Exactly, so how can you make a cheap realistic boost phase decoy?

Well, the spy sats looking for launch plumes will look at the temperature of the
plume, the size of the plume (possibly its spectral signature as well to figure
out what chemicals are being used as fuel), its speed, acceleration, and
trajectory angle. Plotting out the trajectory of the missile, and calculating
how much fuel of what type is being burned, they can figure out A) What the mass
of the total vehicle is at any given point, and therefore whether it is a decoy
or a real missile. If you make it the same mass, then you have to use the same
amount of fuel in the first and possibly second stages (depends on how long your
decoy is supposed to maintain the ruse). The main cost of a solid fuel missile
is in fact the solid fuel (not counting the logistics and launch facilities
required as well).

My personal opinion is a boost phase decoy is either easy to detect, or else so
expensive that its a waste, you might as well just use a real missile with a

> >Actually, Hokkaido Island in Japan is in an excellent position to launch,
> That's about a thousand miles away, probably too far.

>From North Korea? Its actually about 500 miles coast to coast. Any missile
should still be in its upper boost phase at that point as it is passing over,
however, they will not necesarily intercept directly overhead, but far out into
the Sea of Japan. Radar sites on Honshu, Kyusho and Hokkaido should spot
launched missiles before they have acheived more than ten miles altitude (at the
very least satellites should detect launch pretty early and notify batteries on
Hokkaido) Assuming we are using a Patriot PAC4 missile system, or its advanced
THAAD equivalent, and even if the radar is line of sight, battery radars should
lock on before the targets are halfway over the sea of Japan, at about 30-40
miles altitude, at Mach 3-5 at best.

Now, the Japanese may require that all intercepts occur directly overhead, so
any radioactive debris passes over and falls into the Pacific.

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