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- From: wwo@vax5.cit.cornell.edu (Thomas Schoene)
- Subject: Re: Discussion Of Shallow Water ASW
- Message-ID: <Bxx2EL.5w@law7.DaytonOH.NCR.COM>
- Sender: military@law7.DaytonOH.NCR.COM (Sci.Military Login)
- Organization: Cornell University
- References: <BxKAzI.FH0@law7.DaytonOH.NCR.COM>
- Date: Wed, 18 Nov 1992 14:47:09 GMT
- Approved: military@law7.daytonoh.ncr.com
- Lines: 51
-
-
- From wwo@vax5.cit.cornell.edu (Thomas Schoene)
-
- In article <BxKAzI.FH0@law7.DaytonOH.NCR.COM>,
- bphdarcy@ubvmsb.cc.buffalo.edu (Sean J. Roc D'Arcy) writes:
-
- > First, it is my understanding that shallow water does not allways
- > deteriorate sonar perfomance. A lot of this depends on the sea floor and
- > the local conditions of the water. I have seen a few submarine books t
- > (along with a few "attemped" computer simulations) make shallow water sonar
- > performance to be nill. While the ability to use long array devices and
- > some convergence zones may be lost, I still wouldn't say that sonar
- > performance is "severely degraded."
- >
- > Some forms of active sonar do very well in shallow water (medium freq. hull
- > mount I think). Again a lot would depend on the geography. It is probably
- > a lot easier to find a submarine in the perisan gulf than off the coast of
- > Norway.
- One of the problems the USN has is that its hull sonars have tended to be LF
- rather than MF in recent years to improve deep water range and so forth. I
- understand that the LF active sonar tends to penetrate bottom mud and so forth
- and either be absorbed or create multiple echoes. (This is from memory so I
- may be way off here) As to towed systems they tend to ride relatively deep,
- especially at slow speeds, and don't function well when bent (when the towing
- ship maneuvers). This would badly undermine their utility.
-
- > In shallow water other ASW devices besides sonar excell. IR and actual
- > visual spotting come to mind. MAD should still retain most if not all of
- > its effectiveness. Also, I would think surface wakes produced by the
- > submerged boat would be much more prominant.
- The problem with these is that spotting ranged are much worse than with
- acoustic systems, requiring lots of platforms to cover an area like the Gulf.
-
- > I think one of the major problems in shallow water ASW is the performance
- > of ASW torpedoes. How well would a Mk-46 fare in a shallow water
- > situation? In many shallow water situations depth charges might be more
- > effective.
- >
- This was (is?) a problem for several reasons. One big one is that the
- batteries on many torps don't activate until they hit seawater and in real
- shallow situations they would bottom before the prop kicks in. Also the ttack
- sonar is more likely to be confused by bottom debris, currents etc. I
- understand that this is one reason that the new French Murene can track
- multiple targets, to help sort real targets from junk.
-
- --
- Tom Schoene
- wwo@cornella.cit.cornell.edu -or- wwo@vax5.cit.cornell.edu
- -------------------------------------------------------------------
- Back off man. I'm a political scientist!
-
-