Hiraga's Fast BB/BC Experimental Proposals Aug. 1917:

②'②''
Displacement (t)38800375003770036500388004400047500
Length wl. (m)248.4240.8240.8298.7
Speed (kt)303029.529.75323536
Propulsion (shp)90000120000112000160000210000250000
Main Armament5xII 41cm5xII 41cm5xII 41cm5xII 41cm5xII 41cm5xII 41cm5xII 41cm
Belt Armor (mm)229305229

The time was after the Navy had rejected Hiraga's A125 Design. Maybe he was in a very bad mood then and created these crazy proposals, especially the Design ⑤.
You seem to not know about the no.13 designs?

Though recent translation of a japanese book section suggests these are designs for the last two Kiis

You might be interested in this as well:
 
You seem to not know about the no.13 designs?

Though recent translation of a japanese book section suggests these are designs for the last two Kiis

You might be interested in this as well:
The preliminary design of the "No.13 class", or "The last 6 capital ships of the 8-8 Fleet" (They are crazier to some extent) started in 1919.6, and the designs I mentioned in 1917.8. These ones may be the origin of Hiraga's "high-speed capital ship madness";)

The designs above could be seen as the early thoughts of B62, for Hiraga might be getting more familiar with the new propulsion system he first arranged in A125.

And... Yes, there're some designs lies between Nagato and A115, I'm adding it up.
 
The preliminary design of the "No.13 class", or "The last 6 capital ships of the 8-8 Fleet" (They are crazier to some extent) started in 1919.6, and the designs I mentioned in 1917.8. These ones may be the origin of Hiraga's "high-speed capital ship madness";)

The designs above could be seen as the early thoughts of B62, for Hiraga might be getting more familiar with the new propulsion system he first arranged in A125.

And... Yes, there're some designs lies between Nagato and A115, I'm adding it up.
Not madness just the IJN answer to the Lexingtons. 35knots is very high speed for a capital ship, very demanding.
 
Not madness just the IJN answer to the Lexingtons. 35knots is very high speed for a capital ship, very demanding.
Lex is "just" a 33.5kt-BC when she came out though, but maybe IJN's intelligence overestimated some specifications.

Hiraga struggled in the B62 series design (like B62E/F, what are you doing, Hiraga! Wake up!) and eventually cleared his mind. In the end, he gave a 30-kt one, Amagi, and was not considering super-fast capital ships anymore. That's why I called it "madness" for Hiraga at that time - blindly pursuing the "speed" is the wrong way indeed.
 
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Lex is "just" a 33.5kt-BC when she came out though, but maybe IJN's intelligence overestimated some specifications.

Hiraga struggled in the B62 series design (like B62E/F, what are you doing, Hiraga! Wake up!) and eventually cleared his mind. In the end, he gave a 30-kt one, Amagi, and was not considering super-fast capital ships anymore. That's why I called it "madness" for Hiraga at that time - blindly pursuing the "speed" is the wrong way indeed.
Designers rarely make proposals for themselves. There are many discussions preceeding the proposals. Likely the admiralty asked what is required to reach 35 knots.
 
Though recent translation of a japanese book section suggests these are designs for the last two Kiis
Things may be a little complicated... According to my information, the story was like this:

In 1919.10, Hiraga gave the A-M(N) Designs of "New Capital Ships for the 8-8 Fleet", in order to answer the South Dakota-class battleship, after he just finished Amagi's design. However, ship No.9-No.16 of the 8-8 Fleet had already been ordered in 1918, 4 BBs (No.9-No.12) and 4 BCs (No.13-No.16), although no work of design had begun at that time.

So, the "New Capital Ship Design" was to deal with No.9-No.16, and Hiraga had his A-M designs. And it was known that the A-M Designs were very different from each other, so the Navy set up a conference called the "Main Gun Research Conference" (主砲研究会) in Spring 1920, to discuss the specifications of the New Capital Ships.
The Conference finally reached an agreement in 1920.9, that was:
1. The ideal main armament of the New Capital Ship should be 10x 46cm/50 guns.
2. However, the Navy didn't have the technique or facilities to build such a gun (the 48cm/47 5 Year Type Gun exploded in a trial shot, a heavy knock to the Navy), so the first task was to upgrade the facilities.
3. Considering the 2nd point, the time for development, ships No.9 and No.10 will remain the same armament, 5xII 41cm/45, as Tosa and Amagi. Since No.11, ships will be armed with 41cm/50 new guns (the answer to 16"/50 Mk2), of 4xIII or 3xIV (like Design B or E, but with new guns). The ultimate objective, 46cm/50 guns, would be armed on ships further.
4. About the defense, the ship could resist 41cm shells.

Hence, the whole plan was like going with the flow, for there was too much uncertainty in the future, except for Hiraga giving Tosa-Mod and Amagi-Mod designs, and the latter finally became the design of Kii and Owari during those several months (These two got their names in 1920.10, before was ordered in 1921.10). Even the design of ship No.11 had not been determined when the Washington Treaty was signed in 1921.12, nor did the so-called "No.13-class".

But, Hiraga indeed specified some of these ships in a year's time, about "The Last 4 Battlecruisers of the 8-8 Fleet" (八々艦隊最後ノ四隻ノ巡洋戦艦ニ就テ) in the document "About the New Ship Type" (新艦型ニ就テ) (It was weird that the main part of this article was talking about the cruiser Yubari, and Hiraga attached something else at the end.), in 1921.6.11, where he stated:
(No scans, the document is in the book "Collections of Hiraga Yuzuru's Posthumous Manuscripts" (平賀譲遺稿集), but this website has the essentials, just ctrl+f!)

Displacement: 47500-49000t
(Hiraga can tolerate 1 knot down in speed to reach less displacement.)

Armament: 4xII 46cm/45 3rd Year Type, other same as Kii (16xI 14cm/50 3rd Year Type, 4xI 12cm/45 10th Year Type, 8x 61cm Surfaced TT (24x 8th Year Type Torpedoes), 1x Floatplane)
(Hiraga had known the difficulties in developing the 50-cal 46cm guns, so he reduced the requirement to 45-cal.)
(Navweaps makes a mistake here. The 50-cal gun may be used by Design K, but not for this one.)

Armor:
Belt - Resist 16" shells at a distance of >12000m at best, but not worse than >15000m.
Deck - Resist 16" shells at a distance of <20000m at best, but not worse than <18000m.
Barbette - Same as Belt Armor.
Underwater - Resist torpedoes with 200kg warhead.

Propulsions:
Like Kii. (Probably 4x Steam Turbine (oil-only boilers + coal-oil boilers))
29-30kt (According to displacement)
8000mi @ 14kt

This may be the "Final Version" of the No.13-class battlecruiser, which resembles Design K. It's reasonable to say that the No.13-class battlecruiser was developed from Design K, changing Design K's 50-cal guns to 45-cal ones.

And what about the so-called "The Last 2 Kiis"? Officially, the design of ship No.11-No.16 had never been determined, and Hiraga took No.13-No.16 away, so... Only two of you left, No.11 and No.12, 4xIII or 3xIV? As you wish.

Special thanks to 雾岛铃子's article in Zhihu: https://zhuanlan.zhihu.com/p/455360724
 
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I have a different source a japanese small book about the 8-8 ships which provides a similar but somewhat different context. Will post the relevant part regarding gthe Kii and no.13 classes
 
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500,000ton battle ship.
Length : 2200feet/670.56m
Width : 300feet/91.44m
Speed : 42kt
Armament
16inch cannon 100(twin cannon ×50)
5.5 inch cannon 200
4inch cannon 100
Torpedo Tube 200
Crew : 12,000

i monster that could have been required a couple of hundreds boilers
 
Yes that is Hidetaro Kaneda's Dream Battleship.
 
I've once read somewhere that 2.235.000shp required to propel it 42knots or 78km/h I calculated around 324 boilers were required for that much power. Though I do not know how could 6 turbines provide the necessary shaft power to push that much power in the water without the supercavitation effect. Only possibilty is using large propellers like on modern supercarriers and multiple propellers per shaft like on Turbina. The stated shp would be 372.500 per shaft which is too great even for modern ships!
If built a more reasonable speed like 25-30 knots would be acheved at best requiring I don't know maybe only 1/3rd of that shp. Somebody should run a quick calculation on springsharp to produce an approximate value.
 
I've once read somewhere that 2.235.000shp required to propel it 42knots or 78km/h I calculated around 324 boilers were required for that much power. Though I do not know how could 6 turbines provide the necessary shaft power to push that much power in the water without the supercavitation effect. Only possibilty is using large propellers like on modern supercarriers and multiple propellers per shaft like on Turbina. The stated shp would be 372.500 per shaft which is too great even for modern ships!
If built a more reasonable speed like 25-30 knots would be acheved at best requiring I don't know maybe only 1/3rd of that shp. Somebody should run a quick calculation on springsharp to produce an approximate value.
Early designs, I'd bet on multiple propellers per shaft.
 
This is a post ww1 design from between 1919 and 1922 when Kaneda was in command of a naval shipyard.
 
This is a post ww1 design from between 1919 and 1922 when Kaneda was in command of a naval shipyard.
It is? So they'd know about cavitation then... could go either way.

Multiple props per shaft allows them to use existing equipment (and therefore be cheaper), while a single large diameter prop per shaft would require new equipment to cast and machine.

A half-million-ton, 2200ft long battleship would definitely be a national prestige project, so I'm going to lean towards a single enormous diameter prop per shaft, so that the Japanese could brag about the being able to cast 50+ft diameter props.
 
It was not a serious project just Kaneda's own idea for a battleship combining the firepower of an entire fleet because Japan lacked battleships in number. Kaneda was known for such outregious ship proposals, the Hiraga archive also contains a Kaneda design with 7 twin turrets with 3- wing ones and the rest on the centreline.
Here:
Though Kaneda's speciality was naval gunnery but he was a naval engineer who never served on a warship. He was the director of Kure Naval Arsenal between 1922.12.1 and 1923.8.13 so this battleship was likely emerged at that time.
Here is the face behind the name:
http://img.yaplog.jp/img/00/pc/a/z/e/azemitijyouhou/0/608.jpg
 
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I've once read somewhere that 2.235.000shp required to propel it 42knots or 78km/h I calculated around 324 boilers were required for that much power. Though I do not know how could 6 turbines provide the necessary shaft power to push that much power in the water without the supercavitation effect. Only possibilty is using large propellers like on modern supercarriers and multiple propellers per shaft like on Turbina. The stated shp would be 372.500 per shaft which is too great even for modern ships!
If built a more reasonable speed like 25-30 knots would be acheved at best requiring I don't know maybe only 1/3rd of that shp. Somebody should run a quick calculation on springsharp to produce an approximate value.
A project that probably could had been required tens years admitted if they had chance to build a monster of genre. Infact it was impossibile. It was just a prohibited dream.
 
It was not a serious project just Kaneda's own idea for a battleship combining the firepower of an entire fleet because Japan lacked battleships in number. Kaneda was known for such outregious ship proposals, the Hiraga archive also contains a Kaneda design with 7 twin turrets with 3- wing ones and the rest on the centreline.
Here:
Though Kaneda's speciality was naval gunnery but he was a naval engineer who never served on a warship. He was the director of Kure Naval Arsenal between 1922.12.1 and 1923.8.13 so this battleship was likely emerged at that time.
Here is the face behind the name:
http://img.yaplog.jp/img/00/pc/a/z/e/azemitijyouhou/0/608.jpg
I suppose Kaneda was a show-off man !:D
 
I suppose Kaneda was a show-off man !:D
There isn't much avaiable on the net about him, but I doubt it. There are similar projects from different navies. Habbakuk from the UK, Moffett and the the Tillman designs of the USN, a hybrid BBCV from the 1920's from Italy, post H-42 designs from the Germans etc.
 
There isn't much avaiable on the net about him, but I doubt it. There are similar projects from different navies. Habbakuk from the UK, Moffett and the the Tillman designs of the USN, a hybrid BBCV from the 1920's from Italy, post H-42 designs from the Germans etc.
I have some doubts about real projects of Kaneda : i think proposal and speculation are mixed.
 
Did any Japanese design proposals feature 4-gun turrets?
Post Kii designs:
And the Kongo Replacement designs:

Oh and a Myoko preliminary:
 
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Machine translation of the post text at X

"The 1/700 scale aviation battleship Ise Konpeki style if modified version is complete! The hull is a mix of Hasegawa Ise and Fujimi Ryujo, and the aircraft are like those in Konpeki no Fleet, scratch built from junk as an amphibious anti-submarine patrol flying boat. #fictionalship"
 
"BEYOND THE YAMATO CLASS" I get and print this text from a japanese page in 1997, when I believe that internet pages would be eternal. Maybe this is the reason that I dont save the other links in "Planned But Not Built".
i think i will find it on archive.org i hope.
this is ocr of two images about Yamato:
I hope you enjoyed. So sad news for old page mentioned: i am unable to find old archived pages.
 

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