Fuso & Hyuga class BB's

[Stealth]

Well, I don't have any pretty cards to show, I'll leave that to those with more artistic talent. The following are some proposed stats for the remaining Japanese BB classes, the Fusa/Yamashiro and the Hyuga/Ise.

Fuso/Yamashiro
The Fuso class BBs were the battleship version of the Kongos, with 12x14" mains (6 twin turrets) and improved armor. I used the Tennesee class as a basis, and modified to match the Kongos secondaries and some other stats:

Points:41
Speed :2
Main: 15-15-14-11
Secondaries: 7-7-6-5
Tertiaries: 5-5-4
Anti-Air: 7
Armor: 7
Vital:13
Hull :5

SA's
Extended Range 4
Torpedo Defense 1

Hyuga/Ise
The Hyuga/Ise were improved Fusos, but rather than making a near copy of the Fuso I went for the late war variant. After Miday, the Japanese were desperate for carriers. As a stopgap solution, the after pair of 14" guns were removed and a small flight deck was installed. As the mains were now on a par with the Kongos, they have their main valuse but with the Scout Cruiser abilit to simulate their airplane capacity.
Points:47
Speed :2
Main: 14-14-13-11
Secondaries: 7-7-6-5
Tertiaries: 5-5-4
Anti-Air: 7
Armor: 7
Vital:13
Hull :5

SA's
Extended Range 4
Torpedo Defense 1
Scout Planes: At the beginning of your air defense phase, you may choose an enemy ship. Your units roll one extra attack die when making Bomb or Gunnery attacks that ship this turn.

[Captain Gideon]

I'm not sure if the Fuso's were the Battleship version of the Kongo's where did you find this information?

Captain Gideon

[Stealth]

I'm not sure if the Fuso's were the Battleship version of the Kongo's where did you find this information?

Captain Gideon

What I meant by that was these ships were contemporaries. Both classes were laid down and launched between 1910-1915. The Kongos filled the need for battlecruisers, while the Fuso/Yamashiro filled the need for BB's.

[Gebhard]

Hope this is helpful! Let me know if there is something that needs changing.
I tried to customize the ships profile to make it standout from other BBs.

[Rokossovsky]

Fuso -- or was it Yamashiro? -- there is still some confusion which was which in the battle -- capsized (being so topheavy) and went down quickly, after only a few of our destroyers' torpedoes.

Yamashiro made it all the way up the Strait to our cruiser line, where it was pummeled by both cruisers and our old battleships ... but typically, we were firing so many shells we couldn't see which were hitting and which weren't, and it lasted through MANY above-waterline hits.

(Kongo's sistership) Kirishima similarly capsized after some of Washington's 16" blockbusters.

The "pagoda" superstructures were intended to give Japan's longer-ranged guns a range advantage, but they actually undermined their old battleships, defensively.

I have the Bandai 1:2000 "hermaphrodite" carrier conversion of the Ise, by the way. Beautiful ships, they swanned through Halsey's hundreds of torpedo and divebombers unscathed in the Battle of Cape Engano.

In the photo below, my uncompleted Bandai Kongo and Ise are at the top.

Can anyone identify the hull of the Japanese cruiser beneath the A&A Atlanta with the "overhanging" Y turret :cool: )?

And can anyone ID the Japanese destroyer with the A&A Fletcher? ;)

I have another, bigger ship photo under the "Which scale do you prefer?" thread.

[Old Fart]

The Fuso/Yamashiro class underwent modernization in 1933/34. Torpedo
bulges were added, new turbines and space saving boilers were added,
the horizonal protection was increased, the old AA guns were replaced
by four twin mounted 5" guns.

Originally they were the contemporaries of the Pennsylvania class, but
less heavily armored. Much greater detail was paid to watertight sub-
compartments ... after the 1904/05 war with Russia the Japanese
FEARED MINES AND TORPEDOES.

I would recommend:
Hull = 8
Vital Armor = 14
Hull Points = 5

Slow 1
Extended Range 4
Tordepo Defense 1

Main gunnery = Tennessee
Secondary = Kongo
Tertiaries = 4-4-3 ( 4 x 5" per broadside )
AA = 7

Points = 49

Old Fart

[Rokossovsky]

Nonsense.

Remember too that the magazines (and armor protecting it) of Fuso and Yamashiro were more spread out because their guns were: six 2-gun main battery turrets. And -- again -- look at Fuso's sinking by just a few American torpedoes.

These were old ships, nowhere near as modernized as the Kongos, which were their predecessors.

I say:

Armor: 7
Vital Armor: 12
Hull Points: 5

Kongos are 6,12,5, for comparison.

Rodney/Nelson are 9,15,5.

Iowas are 9,15,6

I would go along with 8, 13, 5 for Ise and Hyuga, though.

[Captain Hydro]

Gee, someone got it right. The Fuso was blown in half at the south end of the straight while the Yamashiro got shot up at the north end before "trying" to retreat. In a little note of trivia, both ends of the Fuso actually stayed afloat(unlike the HMS Hood) until the following morning when they were sunk by US cruisers and destroyers

[Old Fart]

Nonsense.

Remember too that the magazines (and armor protecting it) of Fuso and Yamashiro were more spread out because their guns were: six 2-gun main battery turrets. And -- again -- look at Fuso's sinking by just a few American torpedoes.

These were old ships, nowhere near as modernized as the Kongos, which were their predecessors.

I say:

Armor: 7
Vital Armor: 12
Hull Points: 5

Kongos are 6,12,5, for comparison.

Rodney/Nelson are 9,15,5.

Iowas are 9,15,6

I would go along with 8, 13, 5 for Ise and Hyuga, though.

You may be jumping the gun a bit. Truth can be stranger than fiction.
What exactly transpired on that dark night is still somewhat in doubt.
Yes, the results are known ... but not necessarily the how. It has
been reported that during the sinking of the Musashi that a torpedo
actually entered through a hole torn into the ship's side by an earlier
torpedo and penetrated into one of the engine rooms where it exploded.

Life can sometimes roll 4 sixes. And if you believe that WOTC got the
stats right on the Kongo ... think again. To my knowledge none of
the Kongos did the BIG BANG ... yet with a Vital Armor rating of 12 in
WAS ... you can expect it on a fairly regular basis. Again, the
Scharnhorst with a Vital Armor rating of 13 can be expected to do
the BIG BANG on occasion. It seems to me that that the last German
battleship to do the BIG BANG was the Pommern at Jutland ... and it
was a pre-dreadnought. Based on that historical reference ... should
all major German battleships have a Vital Armor rating of 25 or so?
Let's see ... the USS Arizona did the BIG BANG ... oh, that was a lucky
( 4 x 6s ) bomb down the smokestack. The USS Maine did the BIG BANG
... probably someone smoking in one of the magazines. Gee ... based on
history US ships sometimes go BANG.

Be not quick to judge history ... without all the facts.

Old Fart

[zaarin7]

The IJN cruizer looks like a "Aoba" or a "Furutaka", 6 X 2 8" guns 2 forward one aft.

[Big Kahuna]

Old Fart, you are right. The IJN BCs were very light and one suffered heavy damage / mission kill from a pair of 8" shells. The IJN BCs have a VERY light belt and a deck that was not much better, between wars they got an extra inch of deck to become BB...... not. The German BCs were very well protected, really near BB protection. Almost double the IJN belt.

IMO the IJN BC should look more like the axis pocket BB.

[Rokossovsky]

You've got it wrong, BK. OF is arguing that, after modernization, the old Japanese battleships -- the 4 Kongos and Fuso and Yamashiro -- were competitively armored. I'm the one saying they weren't.

Of course, OF, there was the spontaneous magazine explosion destroying Mutsu in June 1943, but that was not combat-related. (There is suspicion it was the work of a crewman (wrongly?) accused of theft.) See the excellent webpage about Mutsu and the salvage of some of its components at:

http://www.bobhenneman.info/mutsuwrk.htm

As to Be not quick to judge history ... without all the facts, you might follow your own advice, OF. This from another webpage:

However, her [Kongo's] luck ran out a month later. On 21 November 1944, soon after passing through the Formosa Strait en route to Japan, she was torpedoed by the U.S. submarine Sealion. The resulting fires apparently were uncontrollable, as Kongo blew up and quickly sank a few hours after she was hit.

It wasn't just Japanese aircraft which were flammable. They also lost most of their carriers to fire, even armored carrier Taiho and Shokaku itself during the Battle of the Philippine Sea.

It has been reported that during the sinking of the Musashi that a torpedo
actually entered through a hole torn into the ship's side by an earlier
torpedo and penetrated into one of the engine rooms where it exploded.

That is what happened to (the Atlanta class) USS Juneau, the morning after the First Battle of Guadalcanal. She had been previously torpedoed in the bow, and then a Japanese submarine torpedo the next day hit exactly the same place and touched off the forward magazines. One turret flew hundreds of feet in the air. Of the 750-man crew, 110 survivors were left in the water, thanks to the surviving tactical commander's belief that doctrine was not to loiter around a sub/snake nest and to Halsey's lack of search and rescue concern (demonstrated again after the Battle Off Samar). By the time any of them were rescued, only 10 were still alive.

Up in the Alaska Historical Library in Juneau, I once looked into the sea of Juneau's crew's young faces at its (Valentines Day 1942) commissioning, knowing virtually all of them would be dead within the year. Sad.

[Rokossovsky]

Not an Aoba/Furutaka, zaarin7. Try again! :)

[Old Fart]

You've got it wrong, BK. OF is arguing that, after modernization, the old Japanese battleships -- the 4 Kongos and Fuso and Yamashiro -- were competitively armored. I'm the one saying they weren't.


As to Be not quick to judge history ... without all the facts, you might follow your own advice, OF. This from another webpage:

However, her [Kongo's] luck ran out a month later. On 21 November 1944, soon after passing through the Formosa Strait en route to Japan, she was torpedoed by the U.S. submarine Sealion. The resulting fires apparently were uncontrollable, as Kongo blew up and quickly sank a few hours after she was hit.

It wasn't just Japanese aircraft which were flammable. They also lost most of their carriers to fire, even armored carrier Taiho and Shokaku itself during the Battle of the Philippine Sea.

Nonsense ...

You have failed to make your case. The fact that the Japanese lost a
lot of ships to fire points out the dismal Japanese damage control
systems. The kongo blew up and sank hours after she was hit ...
if she was the paper tiger that you claim ... she would have blown up
like HMS Barham and sank immediately.

I'll try to make my point again. Real life sometimes rolls 4 x 6s. If I
followed your logic, the Bismarck should be downgraded or given an SA
just as stupid as HMS Hoods ... Unprotected Rudder - when this ship is
hit by a torpedo it cannot leave its sector due to steaming in circles.
I have always thought of the Bismarck episode as a wargame where a
lot of 6s were rolled.

The biggest problem with trying to create a WWII game of naval battles
is that the war gave us few examples of ship to ship combat ... and
some of those were tainted by unusal circumstances. Many were
confusing night affairs where anything could and did happen. Big Kahuna
claims that US underwater protection designs were faulty ... maybe
they were. USS Canberra, a Baltimore class cruiser named in honor of
HMAS Canberra lost at Savo Island, was struck by one aerial torpedo
between number three and four fire rooms, rupturing the bulkhead and
flooding both compartments. The explosion also displaced the outboard
propeller shaft, tearing open the bulkhead and flooding the adjacent
engine rooms. Both the explosion and flooding resulted in severe
machinery damage and the loss of all power.

Does the above example justify Big Kahunas claims. No, one example,
while supporting his claim, does not prove it. Since there are really no
other examples, Big Kahunas claim goes unproven.

The older Japanese warships are something of an enigma. We know
their original stats. We also know they were modernized in the '30s.
Exactly to what extent and how successfully is the mystery. The fact
that one of the Fusos suffered 2 -3 (?) torpedo hits and catastrophically
exploded doesn't really prove she had weak armor ... perhaps it was
just a lucky hit in just the right place at just the right angle.

BTW: I consider Armor 8, Vital Armor 14 to be weak. The modern
standard for WWII would be Armor 9, Vital Armor 15. Anything less
than these should probably considered as obsolete. WOTC Kongo
stats scream original stats ... not modernized stats ... or did you not
notice this. One hell of an arguement can be made for increasing the
Scharnhorsts stats to Armor 8, Vital Armor 14 and Torpedo Defense 1.

To those of you who blindly accept WOTCs ship stats ... would you
like to buy a bridge in Brooklynn?

Old Fart

[Big Kahuna]

make no “claim”,the USN built angle belt STS bulge protected ships under the “theory” the STS would detonate the torpedo and the liquid filled void would disperse the energy. That theory was inherently flawed and completely disproved. Just because no STS BB were hit by torpedoes, does in no way validate the flawed theory. If you do enough searching you will indeed find enough referenced to the problem and I’ve cut and pasted at least one already. Liquid in a solid container, in this case STS steel, does not “absorb” a blast. PERIOD.

You can start here and if you don't fall asleep maybe we can talk about liquid filled void spaces encased in STS steel between an angle belt may or maynot absorb blast.

http://kbismarck.org/forum/viewtopic.php?t=110&postdays=0&postorder=asc&start=15


“regard to your claim that, "Most of the 'revisionism' comes from people who began studying these subjects only a few years ago. I've been working on these issues for more than 40 years now." Well, for someone who has been working on these issues for so many years you didn't appear to know much about the plating plans untill we found them for you, nor much of the material Dave has dug up welding until he shared it. You may opine most that what can be discovered has already been discovered, but recent events clearly indicate that this isn't the case. As for how unusal the separation of the distal extremity of a warship is following torpedo damage, it seems like there are ample cases to study involving a number of ships from several nations. Perhaps they all used "sophmoric" welding techniques.
I also note that you maintain that, "Some things, like vibrations of large structures under irregular oscillating loads, are very difficult to predict even today. "Making a mistake" in the prediction of the vibration mode of a large warship with an unusual hull design and making a mistake in the design of a simple welded joint are, however, two different things." Here you claim that the attachment of the modular stern involved a simple weld joint, when we bloody well know it was a compound joint of revited and welded structures, the underlaying framing of which we know next to nothing about. So you blithly dismiss the complexities in one case and then use complexities to excuse negative effects of another case. Is there any wonder I am beginning to doubt your views as being dispassionate?
And when you claim that the torpedo bulkhead joint of the Iowa class "wasn't sophmoric. It worked. Who could ask for anything more?", I ponder on what body of evidence this opinion rests? Certainly, we see a number of caison tests that seem to indicate problems with the system. Moreover, not running the TBD all the way to the ship's bottom created a discontinuity -- at least as defined by some naval architecs I know who have examined the structure. Yet there you go again, defending one approach while castigating another.”

For me and IMO, I just don’t think the Iowa merits an anti-torpedo bonus. She has a never tested design and one that maybe or in all probability was critically flawed.



The IJN BC were very weak in the belt, that is a FACT. She maybe able to hold out 8" shell fire but anything bigger will completely penetrate. Meaning the protection is USELESS against any other BC or BB. The historical facts bare this out, this is the ONLY BC that was critically / mortally wounded from CA fire and outside of the partly self-inflicted SD problems the IJN BC will remain the only class of capital ships done in by CA shell hits.

[Big Kahuna]

BTW: I consider Armor 8, Vital Armor 14 to be weak. The modern
standard for WWII would be Armor 9, Vital Armor 15. Anything less
than these should probably considered as obsolete. WOTC Kongo
stats scream original stats ... not modernized stats ... or did you not
notice this. One hell of an arguement can be made for increasing the
Scharnhorsts stats to Armor 8, Vital Armor 14 and Torpedo Defense 1.



As far as I know the IJN BC upgrade was ulmost all deck and not much there to make them BB. The Belt is weak, very very weak, maybe just able to keep out 8" shell fire but NOTHING bigger. The multi decks well just about useless once again. Meaning anything larger then a CA could go right through at all plunging ranges.

I don't have many ship but the Scharnhorst should be very strong in Armor / vitals, she is about where the Bismarck was and she should be OK in an upclose fight where her guns have OK punching power, plunging fire at range she should be very weak. I would like to see an upgrades BC with 6 15" guns. Maybe I'll use some extra turrets off a Bismarck I will also make my 20" gun Cyo・Yamato:超・大和 I just have to scan in the Yamato card and photoshop it... right after I make my Tirpitz...

[CruorVult]

rokossovsky's cruiser looks like the oyodo. I don't think that's a turret at the stern, probably catapults. I'm pretty sure I can see where two poles of its tripod foremast fit into the deck on your model, and where the funnel piece fits. getting the destroyer's name or even class just right is harder, but it looks like it's had the AA refit most japanese destroyers underwent. I'm gonna say kagero or yugumo class for sure

[CruorVult]

As far as I know the IJN BC upgrade was ulmost all deck and not much there to make them BB. The Belt is weak, very very weak, maybe just able to keep out 8" shell fire but NOTHING bigger. The multi decks well just about useless once again. Meaning anything larger then a CA could go right through at all plunging ranges.

I don't have many ship but the Scharnhorst should be very strong in Armor / vitals, she is about where the Bismarck was and she should be OK in an upclose fight where her guns have OK punching power, plunging fire at range she should be very weak. I would like to see an upgrades BC with 6 15" guns. Maybe I'll use some extra turrets off a Bismarck I will also make my 20" gun Cyo・Yamato:超・大和 I just have to scan in the Yamato card and photoshop it... right after I make my Tirpitz...

get some schematics of the protective schemes of these ships and where the thick armor was and come back to me

[Rokossovsky]

Very impressive, CruorVult! :cool:

You are correct: The 1:2000 Bandai kit is indeed Oyodo (spelt "Ohyodo" on the box) which came along with our very own (albeit antiaircraft-modified, as you said) Yukikaze, a Kagero class destroyer.

But ... WAIT ... you don't have the same kit, do you? ?? :)

[CruorVult]

no, I build 1:700 scale ship kits as a hobby. needless to say, I have a large amount of reference material

[Big Kahuna]

Very well, we can see here the mainly / only horizontal armor was upgraded.

http://en.allexperts.com/e/j/ja/japanese_battleship_kongo.htm
” Kongo and her sisters were therefore given heavier horizontal armour and torpedo bulges,”
We can get her initial design:

http://www.hazegray.org/navhist/battleships/ijn_dr.htm

”Armor: 3-8 inch belt, 1.625-2.25 inch decks, 10 inch barbettes,
9 inch turrets, 10 inch CT”

Don’t know why you want schematics, the belt does not cover much of the ship mainly ending at the citadel. Most if not all these designs from all navies during WWI feature a shallow belt, so diving shells will be an issue. I think the max 8” belt just about says it all, along with the thin deck, even the turret faces are just barely enough to keep out CA fire. Any BC, BB would punch through like a wet noodle. I think upto 1" was added to the deck.


Scharnhorst

Gun first rate of fire 3.5 / minute so 3.5 x 9 = 31.5 shells a minute and can these shells blow through just about any armor? Well not too bad at 16,000 yards we see a penetration of over 13 inches and navel penetration means most / all of the shell goes through, surely enough to at least damage major moving pieces on most BB. Compare that to the Kongo at 16 shells per minute (assume the pretty much standard British ROF for 15” guns) we can see the German BC are really able to put lots of rounds on target in any sort of close shooting vs vertical armor. Hence should be rolling LOTS of dice in this game, at least upto say range 2. Horizontal penetration is OK for a 11” gun, this ain’t no Rodney that’s for sure.

Now Armor: I think I said was like the Bismarck:
http://www.kbismarck.com/design.html

What is that like a 14" belt and a 6 inch deck?

[Count_Ciano]

Well, Big Kahuna, based on what I found here on the Kongos:

http://www.voodoo.cz/battleships/

And penetration data I found for 2 different types of 8 inch guns commonly in use by the USN during world war 2

http://www.navweaps.com/Weapons/WNUS_8-55_mk9.htm
http://www.navweaps.com/Weapons/WNUS_8-55_mk12-15.htm

You may be onto something! It would indeed appear that the Kongos had insufficient armor to keep out 8 inch shells at ranges of 15000 yards and less. In fact, even the "crap-tastic" Italian rebuilds carried more armor than the Kongos, despite being almost as fast and nearly 10000 tons lighter!:eek:

Mind you, the Kongos were meant as carrier escorts and being the fastest BB in the IJN at the time, they were the best ships for the job! :cool:

[CruorVult]

Don’t know why you want schematicshttp://www.kbismarck.com/design.html

why do I want the schematics when I have them already?

it was not meant to be.. play the game and enjoy

[zaarin7]

By WW II the IJN considered the "Kongo" class more sacrificial than the rest of the battleline. Pre-war IJN thinking was that the USN would advance across the pacific and be attacked by land based air, submarines and the carrier fleet. The IJN went for a faster battleline than the USN. This would allow them to pick when to engage in the final gunnery battle with the USN fleet hopefully reduced to parity in the advance across the pacific.

[Big Kahuna]

why do I want the schematics when I have them already? it was not meant to be.. play the game and enjoy


Gee you asked me to get them, then you come back all condescending. The “plans” show the German BCs have a whole lot more armor and a whole lot more shells vs the Kongo and it was just as I have stated a long time before your post that the German BC were near Bismarck in armor. I’ve also asserted here and elsewhere the German capital ships are lethal at close range where RoF and high velocity would just tear apart any other capital ship, even the 11” shell has a chance of either penetrating or jamming the turrets of the biggest BB as an aside only the Bismarck has extensive 6” side armor above the belt to keep out ranged CA fire and secondary BB fire.

I agree that I should "enjoy" but some of the fun of playing with little ships is gain an understanding of their real world abilities and failures.

[Big Kahuna]

By WW II the IJN considered the "Kongo" class more sacrificial than the rest of the battleline. Pre-war IJN thinking was that the USN would advance across the pacific and be attacked by land based air, submarines and the carrier fleet. The IJN went for a faster battleline than the USN. This would allow them to pick when to engage in the final gunnery battle with the USN fleet hopefully reduced to parity in the advance across the pacific.

I would assume it was true that IJN BC were going to be used like British BC, that said they kind of fell into the roll of CV escort because of their speed and IF there was a CV escort clash at night then the BC would be lethal against CA and the like. They were indeed useful ships because of gun size and speed, so were the German BC, which were a whole lot newer and I’m sure far more expensive. All German capital ships had better penetration then the general calculations would show due to their better head design, while the IJN has poorer performance due to their roll as diving shells where the head design is compromised to quickly horizontal travel the shell when it hits water. All in all the IJN design was better against all ships outside of the STS hulled modern BB like the SD and newer where the bulge and belt go all the way to the bottom. Against a shallow belt BB like most / all prewar BB this is lethal shell hit (below the belt).

In checking I found that the Mutsu fires at 2.5 rounds a minute so that would be 20 rounds a minute for the ship vs 16 for the USN 16” prewar BB. Not a bad ship, all IJN 14” were just about the same as the British 14” which is an OK gun with a 2.0 rounds a minute and good plunging fire.

[Barry Kendall]

First, a question: Where does one find these very nice-looking 1/2000 Bandai kits? I have an old unbuilt Hood, Bismarck and KG V (smiles broadly) (no Prinz Eugen, frowns) but have had them for years and haven't seen the Japanese stuff. It's certainly close enough to game with!

Second, a correction: Arizona did NOT receive a bomb down her funnel--that's an old myth perpetuated by the writeup in the Revell Arizona model kit instructions. Dives on the wreck found the funnel screen intact.

The film of Arizona's loss shows black boiler smoke and ash shooting out of the stack from overpressure inside the hull resulting from the forward magazine explosion.

Arizona took an AP bomb on her foredeck in the vicinity of the B Turret barbette (but NOT through the turret) which detonated the forward magazines. There is also speculation that she might have suffered some concussive damage to hull or compartments from a previous near-miss, but in any case the forward bomb hit would have been fatal.

The bulges added to Fuso and Yamashiro were at least as much intended to increase buoyancy as to add protection following their rebuilds with the massive pagoda masts. While these structures made over-the-horizon main gun direction possible, they also destabilized the ships.

Fuso and Yamashiro were NOT expanded "battleship editions" of the Kongo class. They were domestic designs built concurrently with Kongo, which was designed and built in Britain with Japanese participation. The three sisters to Kongo were copies built in Japanese yards.

The Kongos' design was far superior to that of F and Y, which is why they received more significant upgrades in the 1930s. F and Y were very much second line units even before the war began.

The reason a division of Kongos was committed to the Guadalcanal fighting was that they were regarded as being fast enough to get in, engage in night bombardment, and get out before Allied air could find them. They were risked because they were regarded as more expendable than Nagato/Mutsu yet more survivable than either the Fusos or the Hyugas.

Hyuga/Ise were improvements based on experience with the Fusos and actually come closest to the description of "battleship versions of Kongo."

[zaarin7]

I bassed what I said on how the ships opperated and on what is known of IJN pre-WW II planning.

As to the following I will have to read up to find the source. but here goes on Arizona. I believe I read it in Norman Friedman's US Battleships, An Illustrated Design History.

The AP "bombs" the B5N2 "Kates" were dropping that morning were converted naval large calliber rounds, 14" or 16" I don't remember which now. They dropped from low altitude to ensure accuracy. The rounds did not develop enough velocity to penetrate the normal steel decks and the armored main deck.

We know from the film farely well where the shell hit, IIRC starbord side abaft "B" tuuret. We also know reasonably well the ballistic arc of the shell. We also know the internal layout of the ship in that area very well.

The powder in the bags for the 14" guns is very stable. It's engineered that way. Thats why there are small pockets with black powder sewn into each end to help the explosion along.

All USN BB's of the older classes were re-built between the wars. Part of that re-build was to give the ships catapults and spotter aircraft. Often on the older ships the only place to put those catapults was on the turret roofs. At that time the catapults could only be fired by compressed air, which would have meant drilling a hole in the roof of the turret for an air line thus weaking it not an option, or black powder.

Space was made for a small magazine of black powder in the ships under the armor deck. Everybody got reminded how dangerous the stuff is and went on there way.

Now back to those known ship plans and all that earlier stuff. Above the armor deck was a paint locker. And beside that paint locker was a hatch in the armor deck. And guess what was right under that hatch..that black powder magazine surrounded by tons and tons of gun propellant. And guess were this whole area lies...right near the most probable terminal point for that shell on that morning.

The ship was at peace time condition which meant that hatch would have been open. And anybody who dosen't think paint will burn go read a can. And I shoot black powder guns so I know how unfriendly that stuff is. And as an example of how stable the main gun propellant was unburnt grains were found on the stern of the ship ahead, Tennessee IIRC.