Path: utzoo!utgpu!watmath!att!cbnews!military
From: dritchey@ihlpb.att.com (Donald L Ritchey)
Newsgroups: sci.military
Subject: Re: B-2 Question
Message-ID: <8884@cbnews.ATT.COM>
Date: 9 Aug 89 03:57:51 GMT
Sender: military@cbnews.ATT.COM
Lines: 70
Approved: military@att.att.com



From: dritchey@ihlpb.att.com (Donald L Ritchey)
Summary:  

portal!cup.portal.com!mmm@apple.com:
In article (Message-ID:  <8831@cbnews.ATT.COM>), you wrote

> Approved: military@att.att.com
> 
> 
> 
> From: portal!cup.portal.com!mmm@apple.com
> In article <8751@cbnews.ATT.COM> berman-andrew@YALE.ARPA (Andrew P. Berman) wr
>>Third, how did they knock down enemy aircraft before the
>>invention of radar, and could those tactics be used against the B-2?
> 
> I remember seeing pictures of device used during WW2 which looked like
> giant ear trumpets.  Depending on the weather, you might hear a plane
> before you can see it.  By the time you hear a B-2, however, it will
> probably be too late.
> 
> 
> [mod.note: similar gizmos were used to locate enemy artillery for
> counterbattery purposes.  -  Bill ]

To the best of my knowledge, these may still be in use in less
developed countries and (probably) the Warsaw Pact (they never seem to
throw ANYTHING away).  The system is called a "sound ranging base" and
used an array of very carefully surveyed low-pass microphones that fed
to a central measurement base.  The arrival times of the shock waves of
the muzzle bursts were plotted on special charts and maps and could
fairly accurately locate a firing battery in a reasonable amount of
time.  The system usually worked in conjunction with flash locating bases
(sometimes co-located with the sound bases) to tell the sound base when
to turn on the equipment and start to record.  The flash bases worked
on a triangulation system somewhat like the fire and smoke location
towers for the forest service (remember the Smokey the Bear public
service spots.)

The system was limited to a small number of targeting attempts per
hour (not sure of the exact number) and the interference of multiple
simultaneous firing points also degraded the results.  The modern
counter-battery radar system can track multiple set of incoming rounds
and project firing points in near-real time, but the disadvantage is
that it is an active system and the other side can tell when you have
turned it on. The flash and sound bases were passive and used land-line
and thus were very difficult to determine if they were in place and/or
active. 

Every military advance carries some trade-offs, you just have to
evaluate whether the advantages outweigh the costs.  Here the ability
to catch an artillery battery on the first or second volley and
accurately reverse to the firing point was very worth the added risks
of an active radar signature.


Don Ritchey       dritchey@cbnewsc.att.com
(or in real life) dritchey@ihlpb.att.com
AT&T Bell Labs IH 1D-409
Naperville, IL 60566
(312) 979-6179

[ Note to Moderator:  this is second hand from memory of old artillery
  education films when I was in the Army, you might want to solicit
  comments from those who KNOW what they are talking about.  It might
  prove to be an enlightening discussion line, particularly about the
  cost/benefit ratio for the various counter-battery options.
      Don.
]