Re: [OT]Naval Warfare the case for the BB

Since no-one has complained about the OT-ness, and several people have
asked to be CC'd on this thread, I'll continue on the newsgroup.
Should anyone object in future, I'll move it to e-mail, and no offense
will be taken. My thanks for everyone's indulgence, and I'll make it as
On-Topic as I can.

Imre A. Szabo wrote:

> I personally don't like Tomahawks on Iowa's specifically because they
> aren't armored.

Minor nit-pick: yes they are, about 6" worth, plus blow-out panels. But
that's not much in comparison to the belt. The secondary 5", now they're
not armoured.

>  There have been several capital ships (BB's and BC's)
> severely damaged or sunk because of un-protected magazines.  The
explosion
> that put the Hood down didn't happen where main magazines were, but
rather
> where the spare torpedo warheads were stored.

...and also the newly-fitted Unrotated Projectiles (anti-aircraft
rockets) were stored in crates in companionways near the 4" magazine due
to lack of space. Exactly what caused the Hood to go Boom is still not
clear: I favour an 8" from the Prinz Eugen starting a fire aft of X
turret myself, (based on testimony of a neighbour who was one of the 3
survivors), but it could have been a 15".

>  There was no armor protection there.

Um. Yes there was, in the magazine proper. The Ready-Use ammunition was
another matter, and this is what you're referring to, right? For
lurkers, it's usual for unarmoured guns to have the majority of their
ammunition stowed (relatively) safely in the magazines, but a few shells
nearby in unarmoured storage that can be used quickly while shells are
being laboriously transferred up from the mags.

>  If you can't protect a highly dangerous item, don't mount it on a BB.

Or use blow-out panels. Agree with a minor caveat.
 
> > May I recommend
> > Friedman's "Battleship Design and Development". 

> Sounds, I'll have to check it out.

Also wrote excellent books on Submarine design and development, and
Naval Radars. Available through the USNI. I've used his books
extensively in my professional career.
Siegfried Breyer is of course THE authority on German Battleships, and
battleships generally come to think of it.
 
> Sure, the carrier can take it where it has armor, but unless your
opponent is
> stupid, the missiles are going to impact the side of the ship where
there
> isn't any armor...

Two separate points here.

First, you don't have a lot of choice when it comes to the trajectory of
the missiles. Sea Skimmers, unless they "pop up" as in the Otomat or
Harpoon 1B model, will hit the side. Period.
The "pop up" manouvre was designed to cause more damage, by a steep
climb followed by a dive just before inpact, to go through the
relatively thin deck armour of most targets and explode in the vitals.
It was generally abandoned when it was found that this made the
sea-skimmer much easier to hit by the CiWS of the time (ie 23mm and
30mm), and when ships stopped having much side armour.
An AS-6 KINGFISH OTOH comes in from 25,000m, at hypersonic speed (FASTER
than a 16" by a long way) in an 80' dive. That's nearly vertical.
Doesn't matter if you shoot away the white-hot wings etc if you do it at
much less than 10,000m, as it's only a few seconds before impact (it
slows quite a bit as it hits the thicker atmosphere, but is still going
way over 500m/sec) Worst thing is that if you set off the warhead, it
will scatter half-tonne chunks of airframe in a shotgun pattern that may
well be more damaging than a near-miss in the sea.
Should such a beastie hit the side of the ship, one that's
well-armoured, it's unlikely that the fuse will go off when it hits, as
it's such a glancing blow. It will go off when it hits the water a few
milliseconds later though. Same effect as a torpedo hit _not_ under the
keel, can easily cause seperation of armour belt from the main structure
of the ship, multiple leaks etc, and the shock could break ankles, KO
equipment and unseat turrets from their rings. But all in all, far less
dangerous than a hit on the deck.

Secondly, a note about Deck Armour. Most ships (CVs excluded) have deck
armour that's in layers. This is partially for stability reasons, don't
want too much weight up too high. But also because of the way plunging
fire works.

Bombs and shells don't hit very fast. The terminal velocity of a 16"
shell is barely above Mach 1, 300 m/sec, and bombs are often only 200
m/sec.

This means that, given the way the warheads work, you want to:
a) Slow the warhead down so it doesn't go deep (if small)
b) Initiate the fuse quick-smart so the hypersonic chunks of ironmongery
it will generate don't get too deep.
c) Have a secondary layer to catch most of the splinters as soon as
possible
d) have a tertiary layer that will then stop the remaining large chunks
that have gotten through c)

That's why in WW2, a typical ship would have:
a) A "burster" deck, thick enough to cause fuse initiation
b) A "splinter" deck, which would catch the pesky splinters that cut
fuel lines, disable electrical systems, kill people etc
c) A "main" deck that would maybe catch the football-sized chunks that
made it through.

This works pretty well vs most warheads. Incendiary warheads,
delayed-action warheads, and AP warheads which go through burster and
splinter before going off can all defeat it to some degree, but
nothing's perfect. In order to physically stop a big warhead (or
crashing/landing aircraft), you need a very thick layer indeed. The CVs
have this, the BBs don't. And can't because of metacentric height if
they're to have adequate armour for the citadel.


> The flight decks aren't going to stop plunging fire very well.  To
much
> kinetic energy from something design to penetrate heavier armor then
the
> flight deck.

You're right, a 16" AP or SAP shell would probably go through, mainly
because of the momentum rather than speed. They actually hit quite
slowly compared to some hi-diving missiles.
 
> There is no reason why can't have a massive number of mini-attenas the
size of
> cellular phone.

Antennae = EMP vulnerabilities. Call em lightning rods.

>
> > Though only 2 operational, as the relevant magazine would be flooded
as
> > a safety measure. Maybe it's my British Heritage, but such names as
> > Hood, Queen Mary etc spring to mind.
> 
> That depends of the designs of the magazines...

Not at all. Wait long enough to see that the flames are only coming from
the turret, and it's too late if they're not. I know of no ship
commander who wouldn't immediately order the flooding of the mag in this
case. Usually such orders are superfluous, as the local gun or magazine
commander has already done it. Often this means that they die.
  
> For 6 hours the ship won't be able to provide ground support, if the
AS-6
> doesn't hit the side.  But what if it does hit the side.

Same as a torpedo hit not under the keel. A bit of a crap shoot. 

> Use multiple electric propulsars and you don't have the shaft problem.
> Civilian ships have been using them for years.  It is past time for an
> experimental live fire test to see how they would hold up to damage.

News to me... the only propulsors I know of on large ships are the ones
on the FFG-7s (auxiliary steering). They're radically underpowered for
the job. AFAIK no ship over 2500 tonnes has propulsors as its main
drive.

Now pump jets are another matter. The UK "Trafalger" class subs have em,
for stealth reasons. I know not about the Seawolf and Centurions. But
these are just as susceptible to shock.

Also, remember that the USN at one stage used turbo-electric powerplants
on some of its Battleships. In this case, the steam turbines drove a
dynamo that produced current for electric motors connected to the
relatively short shafts. Saved a lot of weight in the Gearbox, a geat
success.

Until the first battle vs the IJN, where after exactly one shell that
didn't even penetrate caused myriads of minor leaks, 100 kv MegaAmp arcs
that welded machinery together, melted bus bars, and burnt many sailors.
The ship was KO'd for several years, and took months to get back to a
place it could be repaired. Had the weather been anything other than
unseasonably calm, with many safe anchorages along the way during bad
weather, she would have been lost.

> If the Bismarck had been a KGV or Iowa, then it would have probably
been
> rescued.

Towed to port from mid-Atlantic during the winter? See below.

> > A 100,000 tonne ship in littoral waters that has its propulsion KO'd
is
> > a nightmare. Towing it out of battle would be an interesting
exercise.
 
> With 200 nm guns why would you go closer then 100 nm to the shore if
there was
> a significant threat?

If you're practicing indiscriminate bombardment of an area, you're
right. A big gun firing many cheap low-tech shells is a great idea, low
risk. The barrel life will be short at this range, but even then you
should be able to get  100 shells off between changes, and a new barrel
will cost no more than an attack aircraft (and way less than the pilot's
training). Of course then there's the cost of the dockyard, the
shipwrights, cranes etc. but that's a once-only payment.
But if you want the fabled 10m accuracy possible with NGFS under the
right circumstances, forget it. And the rounds will take far too long to
get to the target anyway if it's moving. Even a 16" at 30,000m - 15 nm -
took well over 50 secs from Bang to Boom. Had to, muzzle velocity is 
about 1000 m/sec, it arrives nearly subsonic (400 m/sec), and has to
travel through an arc rather than a straight line. The only reason it
takes such little time is that much of the trajectory is in very thin
air - it's on the way down it really hits a wall.

Of course you can boost the range via Base-bleed and RAP (whichj extend
the dwell time at high altitude, so a little goes a very long way). And
improve accuracy by having terminal guidance.

What was that about "cheap"? Because unlike bombs, these have to take
100g+ accelerations with rates of onset of 10000g/sec. This is quite
doable - heck, proximity fuses did this in 1942 - but not cheap OR not
reliable.

Frankly, the helo or Ground attack aircraft 5 minutes away that can seek
its own target sounds a heck of a lot better than a shell 10 minutes
away that can't. Unless you can re-target in flight (and possibly get
jammed, and what was that about "cheap" again?)

> > There's a very good case for a new Monitor,

>  I said I wanted a modernized BB
> with the Montana as the base line.

I suspect we differ less than it appears. I'd go for the Arsenal Ship
myself. But that's maybe because I was involved in some of the design
study work for it, where all the above was considered. Re NGFS, my
conclusion was "Think Erebus, but faster, not Yamato and Iowa". In the
short term, a navalised MLRS and (that large missile compatible with the
launcher whose name escapes me) would be in order.

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