From: "Paul F Austin" <paustin@digital.net>
Newsgroups: sci.military.naval
Subject: Re: Why only single mounts in the USN now?
Date: Fri, 30 Oct 1998 16:31:35 -0500

TMOliver wrote in message <363A1CDB.D8F045DE@iamerica.net>...
>David E. Powell wrote:
>>
>> How come the USN only goes with single gun turrets for 76mm and 5 inch
guns
>> nowadays? Is it to decrease shock from other weapon firing, increase
>> stability, or basically because the single guns are rapid fire to the
point
>> where a brace per turret (twin turrets) would be "overkill?"
...
>The complexity of the feeding mechanism for a rapid fire
>automated mount is substantial (as is its size and weight).
>Two or three tubes requires 3 separate feeding mechanism and
>a mount base diameter too large for installation on current
>combatants.  Dependability/durability factors decrease
>enormously, as a casualty to any one barrel, breech mech. or
>loader likely disables the entire mount.


In pre-WW II warships, the length of the ship was determined by speed
requirements and the battery required. Guns and engineering spaces were the
primary consumers of ship-length. In particular, length on the centerline is
particularly precious.

Multiple gun turrets were employed to conserve length and to a lesser
extend, displacement. A turret, associated barbette and magazine was a great
consumer of length of ship and for a given level of firepower, multi-tube
turrets would fit in a shorter ship or make room for more engineering plant.

In post- WW II designs, _antennas_ are the primary consumers of ship length.
If you look at a modern combattant, the masts and antennas fill the center
section of the ship. Since phased array antennas and shared aperature
antennas became available, the problem isn't as bad as it was but go back
and look at pictures of e.g., the Oklahoma City to see what I mean.

Modern ships are much more _volume_ limited than ships designed prior to WW
II with magazine space filled with low density missiles. That's why a
missile ship looks so "un-warlike".

Since gun systems have reduced priority there isn't a great incentive to
cram more tubes on board using multiple mounts. Gun armament was such a low
priority that the USN traded the Mk42 5/54 mount that on a good day could
manage over 40rpm for the Mk45 that can only manage 10rpm but with much
lower manning cost and maintenance required. The advantage of the Mk45 is
that it has lots more good days than a Mk42 does.

Large numbers of guns were needed in pre-war designs because fire control
was so bad. The technique required firing repeated ladders of rounds to get
the range right and then firing for effect. With modern fire control, that's
not needed. In NGFS missions, the support limit is more likely the number of
fire control channels available rather than the firing rate of the battery.
Most combattants these days can only engage a single gun target at a time.
--
"people of means-decent folk-should be given more votes
than drifters, whores, criminals, degenerates, atheists
and indecent folks-people without means."

Paul F Austin
paustin@digital.net