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Lance Kopplin
 
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Default A Second Look at the Greeneville Collision


"Gary Warner" wrote in message
...

/good stuff snipped/
As an aside: It amazes me that a multi Billion dollar sub with a crew of
over a hundred men, that has not other mission (like fishing or cargo
transport) than to know where it is and how to shoot it's weapons - and

that
has the most sophisticated sonar and other equipment in the world with the
sole reason to be able to detect other ships (and usually other subs that
are TRYING to hide)......it amazes me that they can, even with some
negligence, miss "seeing" a 130 foot fishing boat that is surely making

all
kinds of noise. It's as if a trained marksman on the shooting range
accidentially shot a by stander that was standing 20 feet away, behind

him,
and talking loudly.


The transcripts actually had a lot of good information about this. If
you're
amazed that technology fails on a regular basis, then you clearly need to
learn more about technology (or watch the news a bit more).

On the matter of submarine sonar, the transcripts made it quite clear that
the aspect of a ship changes the amount of sound in the water, i.e. if the
ship is heading directly toward the sub, the sound will be very much muted.
What this means is that you cannot use sound to derive a distance to the
target. Then there was an educational description of TMA (Target Motion
Analysis) which is basically a process of moving the sub so that you can
get triangulation and determine target motion.

You may recall that there was some discussion about doing things too
rapidly, a little thought should make it clear that doing TMA to quickly
can lead to questionable results.

The analogy of shooting someone 20 feet away is off the mark quite a bit.
It was more like hearing someone, too far away to determine how far,
waiting a few minutes, and taking a shot. Still wrong, and the shooter is
completely at fault, but it wasn't like anyone knew the ship was there for
certain. They just did not know that it wasn't, and the CO of the sub was
responsible to know that it wasn't there, for a certainty.

I found the transcripts educational, but a tough read.