The Navy Thread

Immy: Try looking into modeling forums as in ship modeling. They tend to some sort of ID this section or a tips and guides for how to tell various equipment apart.

Who watches the watchmen?

Alright, so in my quest to learn how to tell the ships apart I have learned it is actually quite easy for Kaga and Akagi since there control towers are on opposite sides of the ship. Kaga vs Akagi

But what was more interesting to me is to learn that Akagi had significantly reduced combat capable plane capacity over Kaga.... with both ships having 21 Zeros, and 27 Kates, but Akagi only having 18 Vals to Kagas 27.

Any reason why Akagi would have such a reduced capacity? Appernty she had a more modern fire control director, and thicker Armour, but would that be enough to reduce plane capacity by 9?

Edit: After much more research, I THINK it is Akagi's larger funnel. The sisters funnels really ate into there internal space, and with Akagi's being longer it would take up even more of the ship I would think...... Though I would still like a second oppinion on if thats enough to need to keep an additional 9 planes deconstructed instead of combat ready.....

edited 16th Apr '18 12:27:42 AM by Imca

The funnel could be part of it, and I'm gonna say the armor is probably part of it too, depending on the armor arrangement. As a rule, any carrier with an armored flight deck will not have the ability to carry as many aircraft, since the structural requirements for supporting the armor will eat up a lot of internal volume. Plus, it raises the center of gravity, which can also impact how many aircraft you can keep in the hangar and flight decks.

Other factors could be at play too, such as internal arrangement of machinery and spaces, volume dedicated to things like fuel and ammunition, etc.

EDIT: Did either ship have much in the way of armament? Because that also eats up internal volume, especially for heavier gun systems like the 8 inch turrets that Lexington and Saratoga had earlier in their careers (the guns were removed because they, along with their ammunition, used up a lot of deck space and were mostly useless in practice since surface ships only very rarely found themselves within shooting distance of the faster fleet carriers)

edited 16th Apr '18 11:53:12 AM by AFP

They did, but Kaga was the one with the better armament, and it had more planes.... but that's because its armament was built into the lower deck that had originally ben part of the battleship hull, neither of the two had any thing other then AA guns built into the hanger decks, and Kaga had more of those two.... though agian a much worse director for them.

Ah, I was thinking of the newer ships with the same names.

If I recall correctly, the differing capacities were because of differences in the internal designs of the ships they were built off of. The Akagi was originally an Amagi class, and the Kaga was a Tosa class. Even though the Amagi class was physically larger the internal design required a slightly smaller hangar.

They should have sent a poet.

I guess that makes sense, I just didn't think that would mater too much, because the airplanes were stored in a warehouse that was slaped ontop of the ship, rather then down in the hull of the original battleship.... the photo of the internal design of the funnel gives a good view of how they were set up.

I think it's a matter of the upper superstructure. You can see in pictures of the original ships that the Amagi class has a much thicker central section with two exhaust points, while the Tosa class is much flatter and narrower with only a single exhaust.

They should have sent a poet.

Ahhh, the existing super structure that makes sense, thanksies.

DARPA turns over the prototype USV sub-hunter to the US Navy ONR for further testing and development.

Who watches the watchmen?

They believe they have located the German Submarine U-3523 The very submarine rumored to be carrying fleeing Nazis officers, Nazi gold, and according to conspiracy theories Adolph Hitler himself. The submarine was found embedded in the sea floor at a steep angle only 9 miles away from where the British reported sinking the submarine. Looks like it was mortally stricken and made a it short distance away before it finally went all the way under.

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The Naval Gun at Iwo Jima

A 1945 film about the use of naval gun fire vs the fortifications on Iwo Jima.

The Naval gun at Okinawa

The sister film to the above about the use of naval gun fire directed at Okinawa

edited 21st Apr '18 2:37:46 PM by TuefelHundenIV

Who watches the watchmen?

Alternate proposed designs for Yamato◊

It is neat to see the varying turret layouts and the like considered, I wonder why they didn't go with the 3 foward mounts though.

Edit: One proposed Yamato design had 6x 510mm guns instead of 9x460mm..... I can see why they went with the later, but like....

What....... What would have happened if something like that hit another battleship, I cant imagine even something like Iowa's Armour would have held to that.

edited 22nd Apr '18 2:52:42 PM by Imca

Probably lessons learned from the French Dunkerque-class and ships arranged like it such as the British Nelson-class.. All forward-facing armament meant the ship was blind and undereffective at flank/rear angles and ships are not fast enough nor maneuverable enough to not be caught in a blind angle. They don't live the StuG life.

Basically, a broadside arrangement was always better. At the very least you could always put no less than one of your main batteries to bear against a target then.

edited 22nd Apr '18 4:55:28 PM by MajorTom

I'm guessing the concern with only six really big guns was that they had less redundancy if a turret took a hit or if a gun backfired or something. Also bigger shells are probably harder to handle and load quickly. Plus, we're talking if they hit another battleship, which seemed to be a problem as it was with nine smaller guns firing away as it was, since Japanese naval fire control never quite got to where American fire control was.

There was a similar debate in the Army Air Forces regarding the use of more smaller bombs vs fewer big bombs. The idea was that with a spread of smaller bombs, you were more likely to hit the target, but less likely to do substantial damage. The consensus at the end of the war was that for single reasonably hard targets, you wanted to use the biggest bombs you could drop, with any single hits doing substantial damage (for example, the battleship Tirpitz had something like 27 Tall Boy bombs dropped at it, and was blown out of the water when two of them actually struck their target). For softer area targets, like a deployed military unit or an air base, a spread of smaller bombs worked just fine.

That's what I meant when I said I could see why they went with the 9x460mm arrangement, yea, the volume of fire, and the rate of fire probaly offset any real improvments using half a meter of shell would offer.....

I still have to wonder though assuming one of those 20 inchers hit, would even another BB be able to stand up to it, or would it be game over at that point... does square cube effect explosives in a way that benefits or hinders them?

On top of that, ship design shifted radically away from battleships to aircraft carriers around that time.It's possible they didn't see a need for sheer firepower, given that slugging matches between battleships were becoming increasingly rare and naval air power was proving to be a more potent offensive tool.

IIRC that's why the Super Yamatos never came to fruition.

They should have sent a poet.

Are the Super Yamatos kind of like the Montana B Bs?

It's also not just the size of the shell, but its effectiveness in a variety of ways. IIRC, US 16 inch shells actually penetrated better than Japanese 18 inch shells. Not sure if it had to do with metallurgy or ballistics or fusing or what.

Yeah, similar deal. They officially called A-150 and were going to be larger and better armed. None were ever laid down, they switched all their heavy shipbuilding to aircraft carriers before they could even start.

As soon as aircraft carriers started being practical it was the beginning of the end for battleships. A carrier air wing is a vastly more powerful and flexible weapon than a huge gun.

edited 22nd Apr '18 9:14:18 PM by archonspeaks

They should have sent a poet.

The Dunkerque class thought of that as well. Each quad turret is actually 2 twins compartmentalized from each other. Prevents the whole thing from going out of action in the event of misfire or battle damage. It actually worked, Dunkerque took such a hit at Mers-el-Kebir and had half of one of its turrets blown up but the other half still was working.

Thing is, a battleship could only deliver its payload out to the visible horizon, which for a surface ship was about 25 to 30 miles. But an aircraft carrier can deliver its payload beyond the visible horizon (from the ship itself) out to 100 miles or more.

This Space Intentionally Left Blank.

Right, but the question wasn't one of would it have been worth it, we all know battleships died...

It was what would the impact effects of a half a meter of shell be? Would you score a OHKO at that point?

I don't think the effects would be significantly more dramatic than the effects from a 16 or 18 inch gun.

They should have sent a poet.

Immy: Maybe. We would have to do some guess work given the even bigger gun designs never got very far.

Edit: There is not a lot of readily available info that I can find on the big 20 inch guns the Japanese wanted to use for their Super Yamato ships. There is info on the shells though. There is this PDF document explaining the formula typically used by the USN for calculating penetration values. It is reportedly reasonably accurate.

There is also this Relative armor thickness calculator found on Panzerworld.com You can estimate relative angles of armor protection based on armor slope or potential strike angle of projectile. They explain the math and it looks correct from what I can recall so the calculator should work. Just follow the on page directions to use it.

We have shell mass for the APC type shell they would have likely used but we need muzzle velocities to calculate the rest.

The chances of it being a one hit kill are fairly low. Given Battleships have taken a lot of damage in direct combat unless they got lucky and say hit a magazine, enemy battleships could likely take a few hits at least.

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Not necessarily limits of the horizon because there are ways to overcome that such as spotters including aircraft spotters. The overall limited accuracy of battleships vs other ships had practical limitations on range as well For example I recall the average US battleship accuracy was something 30-33% of all shells fired would hit a battleship or similar sized target inside of an ideal combat range under mostly ideal conditions for a moving target. There is room for greater or less performance but that is the general range of accuracy they could practically achieve at the time.

The guns also had hard limits on how far they could actually send their shots. Courtesy of Nav Weapons website, the US made 16"/50 (40.6 cm) Mark 7 firing either Mark 8 AP or the HC (High Capacity) shells at an angle of 45 degrees would only reach about 23.6 miles. Short of technological experiment form the 60's through the 90's they weren't going to be pushing that range out past that. Even Yamato's big guns only had about 3 more miles of range over the US 16".

Interestingly the US experimented with 18" guns in the 20's but they were actually outranged by the 16" design. The US achieved longer ranges in the 80's with some experimental shell and gun designs but nothing ever fully panned out. The refit costs, cost of running the ships, plus the fact technology had begun to rapidly out pace the big gun method of naval warfare by the end of WWII pretty much doomed the efforts. Even in context of fire support roles carrier craft offered greater flexibility and range.

edited 23rd Apr '18 5:30:04 PM by TuefelHundenIV

Who watches the watchmen?

Sort of, but more about beefing up the offensive capabilities than the defensive capabilities like Montana would have been. The Montanas never aimed to increase the raw power of their armament on a per-gun basis like Super Yamato did, instead simply adding another (better protected) 16" turret armed with the same Mk 7 guns. Montana's big gains were in armor - while Iowa didn't improve protection over Sodak, Montana would have piled on an additional 4" of belt armor, a slightly thicker deck, much thicker barbettes, much thicker bulkheads, and much thicker turret faces. At 16" of belt armor and given the superior metallurgy (and access to rare metals) of American armor over its Japanese counterpart, Montana probably would have been the best protected ship ever built and the only vessel able to legitimately slug it out and trade blow for blow with Yamato and overpower the 70 kiloton behemoth by brute force (Iowa might very well have been capable of defeating Yamato, but such a victory would rely on exploiting Iowa's superior speed and fire control rather than trading blows).

The trade-off was that Montana would have lacked Iowa's impressive speed (28 knots vs 33 knots), though it would still be faster than Yamato (27 knots), as well as Montana being too fat a bastard to go through the Panama Canal.

An 18" gun was considered for the Iowas, but it was actually deemed inferior in range and no better in power than the 16" Mk 7 L/50 gun. Given that it was passed over then, it is unlikely that the 18" gun was considered for the Montana.

Super Yamato would also have increased its armor over its predecessor, but not nearly as much as Montana increased its armor over Iowa and the main goal seemed to be mounting those 20" guns. The raw difference in armor thickness between Super Yamato and Montana would have been much smaller than the difference in protection between Yamato and Iowa, and with that smaller difference in plate thickness, the quality of American armor might very well have made Montana better protected than Super Yamato.

edited 24th Apr '18 9:20:38 PM by Balmung

Imca, Tuffle: There are TONS of books on World War Two ships, start with Janes and go out from there.

Check hobby shops for World War Two books.

Check model building forms - grognards, millnerds etc obsess detail you're looking for.

All night at the computer, cuz people ain't that great. I keep to myself so I won't be on The First 48

So with lots of digging through Japanese documents, I can say with 100% certainty that Izumo from WOWs was an actual design proposition for Yamato, and war-gaming got her true to form including her armament of 9x16 inch guns..... she looks quite like a lot of the sketches, and her dimensions add up......

Which leaves me with a burning question though, why would the design have this much dead space◊, there is so much deck-space here that is just..... dead.

Do you really need that big of a ship for 16-inchers? And couldn't you mound another battery with all that extra space? She just seems amazingly under-gunned for her size, which is probably why they went with A-140-F5 instead of A-140-J2 for Yamato..... But still, whats with all the empty deck space, and why such a massive vessel for 16 inch guns?