The first and last Japanese battlecruisers

[World B4]

I am having trouble finding any technical drawings, artistic interpretations, or specifications for the Kongos as the first was laid down, with 12 inch guns, and the final design of the B-65, with 14 inch guns. Any help would be much appreciated

 

[jeffb]

Some pretty good links on Google:

Some good side elevations but sadly no plan elevations of sister ships Hei and Kirishima

Navy General Board - Kongo Class

Differences between the Kongo's sister ships

Some pretty good photos of original 1913 Kongo and later upgrades

Kongo Yokosuka 1914:

 

[Dilandu]

Technically, the "Ibuki" and "Tsukuba" classes of large armored cruisers, armed with 12-inch guns, were also considered battlecruisers in Japan.

 

[Tzoli]

I need to collect my data so expect a larger post later, but indeed the Tsukuba, Kurama and Ibuki were the heaviest armed armoured cruiser afloat and later re-classified as battlecruisers.

 

[Dilandu]

I need to collect my data so expect a larger post later, but indeed the Tsukuba, Kurama and Ibuki were the heaviest armed armoured cruiser afloat and later re-classified as battlecruisers.

Yep, they were of the very few armored cruisers that actually the same main guns as contemporary battleships (if I recall correctly, the only other example was the German's "Furst Bismark" armored cruiser, but she didn't actually count because the contemporary German battleships were armed only with 24-cm guns)

 

[World B4]

Technically, the "Ibuki" and "Tsukuba" classes of large armored cruisers, armed with 12-inch guns, were also considered battlecruisers in Japan.

And the Izumo and Hyuga classes are considered destroyers

 

[World B4]

I need to collect my data so expect a larger post later, but indeed the Tsukuba, Kurama and Ibuki were the heaviest armed armoured cruiser afloat and later re-classified as battlecruisers.

Yep, they were of the very few armored cruisers that actually the same main guns as contemporary battleships (if I recall correctly, the only other example was the German's "Furst Bismark" armored cruiser, but she didn't actually count because the contemporary German battleships were armed only with 24-cm guns)

The Russians used 10 inch guns on both battleships and the armored cruiser Rurik. American armored cruisers also had 10 inch guns

 

[Dilandu]

The Russians used 10 inch guns on both battleships and the armored cruiser Rurik. American armored cruisers also had 10 inch guns

By the time Rurik (the second one, with 10-inch main guns) was commissioned, the only battleship in Russian Navy left with 10-inch guns was old and outdated "Rostislav" on Black Sea. She clearly wasn't a contemporary ship for "Rurik". "Rurik" in fact was build as armored cruiser analogue to "Imperator Pavel I"-class battleships, but "Imperator Pavel I" were armed with 12-inch main guns.

 

[Tzoli]

This is going to be a long post!
Japan had a number of battlecruisers and a large number of designs or preliminary studies.

Their first battlecruiser classes were the Tsukaba Kurama and Ibuki classes which were at first designated as armoured cruisers but later re-designated as battlecruisers.
Then came the Kongos and their preliminary studies, the Japanese Glorious designs, then the Japanese Lexingtons aka the BC versions of Nagato and the Amagi class with their preliminary studies, the Kii class BC preliminary, then the B-65 designs.

The Kongos were constructed with 356mm cannons not with 305mm though their design history started with such.
The B-65 had originally 310mm (not 300 or 305mm! ) cannons but the design got updated to 356mm after knowledge of the Alaskas came about.

The Tsukuba class armoured cruisers were 2 ships though 6 were ordered with 2x2 305mm/45 and 12x1 152mm/45 weaponry and was reasonably fast with their 40km/h speed but their heavy weaponry (strongest among armoured cruisers) put them closer to capital ships then to cruiser hence their re-designation later.
Images:

https://s8.hostingkartinok.com/uploads/images/2017/11/828bec08ac5a31f4ce666651e8c8a9b3.jpg

https://auctions.c.yimg.jp/images.auctions.yahoo.co.jp/image/dr000/auc0310/users/5/5/5/0/rikaumeda-img640x480-1507631808y0fqtq3801.jpg

https://kknews.cc/zh-my/military/8gxj36n.html

"Ибуки" и "Курама"- броненосные крейсеры или линкоры? / Цусимские форумы

The Kurama and Ibuki often classified as one class of armoured cruisers but their different design number suggests otherwise. Kurama was the first and constructed with Vertical Triple Expansion engines while Ibuki with Steam Turbines. Both had 2x2 305mm/45 and 4x2 203mm/45 weaponry and thus had even stronger armament then the previous Tsukuba class hence they were too redesignated to Battlecruisers.
Images:

https://s015.radikal.ru/i330/1710/3a/7d737f96280a.jpg

https://s019.radikal.ru/i619/1710/d3/d0ec73aa4f16.jpg

"Ибуки" и "Курама"- броненосные крейсеры или линкоры? / Цусимские форумы

The history of the Kongo class is well known, well researched and could be easily accessed on the net. Their preliminary designs however not.
What became the Kongo was first started in 1909 as B-38 with 3x2 305mm/50 and 16x1 152mm/50 weaponry.

http://geo.d51498.com/kigiken/export_warship_1.html

But the IJN was not quite sure of the calibre hence the next two designs B-39 and 40 had 356mm guns in 4 and 3 twin turrets respectively.
B-39-41:

平賀譲デジタルアーカイブ · 〔B39~41、A47~50の所元・一般配置〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 〔〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-40:

平賀譲デジタルアーカイブ · (B.40) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

After these until B-45 all the designs feature 305mm/50 cannons in different arrangement schemes including 3x2, 3x3 4x3 and 4x2.
B-41:

平賀譲デジタルアーカイブ · (B.41) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-45:

平賀譲デジタルアーカイブ · B.45. · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Indicating the IJN preferred this calibre probably because of the cost associated with the larger 356mm calibre. Even the last design study before Kongo was ordered featured 305mm armaments while the Kongo class finally got the stronger 356mm cannons, the standard of pre WW1 of the IJN.
Kongo as finished:

https://imgur.com/uBtsWrm

View: https://i.imgur.com/uBtsWrm.jpg

Hiei as finished:

https://imgur.com/61VMOG0

View: https://i.imgur.com/61VMOG0.jpg

平賀譲デジタルアーカイブ · "HIEI"(防御配置図) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 軍艦比叡 重心位置図(完成常備状態) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 〔軍艦比叡図面?〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Haruna as finished:

https://imgur.com/yFGYFz9

View: https://i.imgur.com/yFGYFz9.jpg

Kirishima as finished:

https://imgur.com/zxXWtPE

View: https://i.imgur.com/zxXWtPE.jpg


B-48 what looks like a modified Kongo:

平賀譲デジタルアーカイブ · 〔〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

After Kongo in 1915 the IJN too played idea of light battlecruisers with either 3 or 4x 305mm cannons the Design X's:

IJN Design X Light Battlecruiser Design by Tzoli on DeviantArt

www.deviantart.com

and it's modified version:

IJN Design X Light Battlecruiser Design 2 by Tzoli on DeviantArt

www.deviantart.com

Then came the Imperial Japanese Navy fastest capital ship proposals the Japanese Lexingtons with 34,5-35knots which of course were damn large ships with 4 twin 41cm cannons:
Design I:

平賀譲デジタルアーカイブ · 大臣報告説明書 要目表共(牧野茂氏記) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 880'-0''×96'-0''×29'-6''×40,850T 35KNOTS×205,000.S.H.P. ALL GEAR AND ALL OIL BURNING · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Design II:

平賀譲デジタルアーカイブ · 大臣報告説明書 要目表共(牧野茂氏記) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 880'-0''×96'-0''×29'-3''×40430T. 34・1/2KNOTS×186,000.S.H.P. ALL GEAR AND OIL BURNING(但シ一缶室ハ混焼) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Design III:

平賀譲デジタルアーカイブ · 大臣報告説明書 要目表共(牧野茂氏記) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 915'-0''×97'-0''×29'-6''×44,500T. 35KNOTS×215,000S.H.P. ALL GEAR AND ALL OIL BURNING · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Design IV:

平賀譲デジタルアーカイブ · 大臣報告説明書 要目表共(牧野茂氏記) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 915'-0''×97'-0''×29'-3''×43,950T. 34・1/2KNOTS×195,000S.H.P. ALL GEAR AND OIL BURNING(但シ一缶室ハ混焼) · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

To be continued with the Amagi, Kii and B-65 designs...

 

[Tzoli]

And the second phase because searching in the Hiraga Archive ain't an easy thing to do!

At around the same time the Kaga Tosa/class design started, it's battlecruiser companion the Amagi class too design was started in 1916 beginning with design B-58 but the 5 turreted Amagi as laid down was only appeared in the last series in 1919 with B-63, until then 4 turrets were considered for this class of vessels.

http://geo.d51498.com/kigiken/88fleet_1.html

B-58-59-60-61:

平賀譲デジタルアーカイブ · 予算用Weight A115 116 117 118 B58 59 60 61 A119 120 121 122 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · on Design A115 116 117 118 B58 59 60 61 A119 A120 A121 A122 (大正五年十二月頃) 平賀造船中佐 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-61-62:

平賀譲デジタルアーカイブ · 〔巡洋戦艦B61・B62の基本計画関係メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 〔巡洋戦艦B62と列国巡洋戦艦との要目比較〕/〔巡洋戦艦B62と扶桑・比叡との要目比較〕/〔進水計算〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 〔各国巡洋戦艦とB62の要目比較表〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-62:

平賀譲デジタルアーカイブ · 〔巡洋戦艦B62の要目検討メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 〔巡洋戦艦B62の装甲検討メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · B62 BATTLE CRUISER〔巡洋戦艦B62一般配置図〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 32knots,38000Tons (B62, 40000Tノ前ニ行ヒタルモノ)〔巡洋戦艦B62までの基本計画関係メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 〔巡洋戦艦B63・B64等の機関検討メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · B62 BATTLE CRUISER〔一般配置図面〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · B62 BATTLE CRUISER〔一般配置図面〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 〔各国巡洋戦艦とB62の要目比較表〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Subvariants:

平賀譲デジタルアーカイブ · Comparison of Designs.〔巡洋戦艦B62に対する検討メモ〕/〔巡洋戦艦B62A~Fの要目・列国の巡洋戦艦の要目との比較〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · A BATTLE CRUISER〔一般配置図面〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · G BATTLE CRUISER〔一般配置図面〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-62-63-64:

平賀譲デジタルアーカイブ · 〔巡洋戦艦B62・B63・B64主要目〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-63

平賀譲デジタルアーカイブ · B63a 41000Tons,29knots〔巡洋戦艦B63aの基本計画関係メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · B63a BATTLE CRUISER〔一般配置図面〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-63 and fixed to B-64 data:

平賀譲デジタルアーカイブ · 〔巡洋戦艦天城型主要目、紀伊型戦艦のデータ記入あり〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

B-64 - Amagi with two funnels:

平賀譲デジタルアーカイブ · B64 41000Tons,30knots〔巡洋戦艦B64の基本計画関係メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · B64 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 軍艦天城、赤城 防禦配置大体図 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · B64 BATTLE CRUISER〔一般配置図面〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · B64巡洋戦艦探照所等配置大体図 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Cross Sections:

平賀譲デジタルアーカイブ · 〔各種巡洋戦艦中央横断図面等〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

Kii preliminaries among them the BC version 'Z':

平賀譲デジタルアーカイブ · 〔メモ〕 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

平賀譲デジタルアーカイブ · 八.六.二日 森田中佐殿 平賀大監 · 東京大学学術資産等アーカイブズ共用サーバ

iiif.dl.itc.u-tokyo.ac.jp

And the last battlecruiser design of Japan the B-65 of WW2:

B-65 Type Battlecruiser Design by Tzoli on DeviantArt

www.deviantart.com

Originally designed with 3x3 310mm weaponry but the design later updated to 3 twin 356mm cannons. I've yet to see a true official sketch of the design but most sources describe her with one catapults and all the 10cm turrets on the main deck, I've changed this giving superfiring positions for the middle turrets as well as standard two catapults.
Also the design history of this warship was rather interesting. It started that the USN Intelligence Service got hold of false knowledge that the IJN building Deutschland like big gun cruisers known as the Chichibu class in the late 1930's, so the USN started designing a large cruiser to counter this fictional Japanese Cruiser class as well as the German Deutschlands. This resulted in the CA series of cruiser designs (Like the CA-2D the 4x3 12" armed battlecruiser / large cruiser) culminating in the Alaska class battlecruisers / Large Cruisers. Then the IJN got news that the USN building these Alaska class "Super Cruisers" and decided to design and build similar vessels to counter them, this became the original B-65 design with 310mm turrets, sometime later when they got more accurate information on the Alaskas armament the decision was taken to update them with twin 356mm turrets and revised / thickened deck armour.

And now the design numbers:
B-12 - Tsukuba class (1904)
B-15 - Ibuki/Kurama class (Kurama) (1904)
B-17 - Ibuki/Kurama class (Ibuki) (1906)
B-39 - Kongo Preliminary (1909) 29.000tons 4x2 356mm
B-40 - Kongo Preliminary (1909) 26.000tons 3x2 356mm
B-41 - Kongo Preliminary (1909) 25.000tons 3x2 305mm
B-42 - Kongo Preliminary (1909) 26.800tons 3x3 305mm
B-43 - Kongo Preliminary (1909) 30.000tons 4x3 305mm
B-45 - Kongo Preliminary (1909) 26.500tons 4x2 305mm
B-46 - Kongo Preliminary (1910) 26.000tons 4x2 305mm
B-46 modified - Kongo class (1910)
B-58 - Amagi Preliminary (1919) 32.600tons 4x2 356mm
B-59 - Amagi Preliminary (1919) 34.200tons 4x2 356mm
B-60 - Amagi Preliminary (1919) 34.900tons 4x2 356mm
B-61 - Amagi Preliminary (1919) 36.600tons 4x2 356mm
B-62 - Amagi Preliminary (1919) 39.900tons 4x2 410mm
B-62A - Amagi Preliminary (1919) 40.000tons 4x2 410mm
B-62B - Amagi Preliminary (1919) 40.000tons 4x2 410mm
B-62C - Amagi Preliminary (1919) 44.000tons 4x2 356mm
B-62D - Amagi Preliminary (1919) 46.000tons 4x2 410mm
B-62E - Amagi Preliminary (1919) 35.000tons 4x2 410mm
B-62F - Amagi Preliminary (1919) 35.000tons 4x2 356mm
B-63 - Amagi Preliminary (1919) 41.000tons 5x2 410mm
B-64 - Amagi class (1919)
B-65 - Kii class Battleship? (1921) Design Z?
B-65 - Large Cruiser design - Super Type A Cruiser (1941) 32.000tons 3x3 310mm
B-65 - Large Cruiser revised design - Super Type A Cruiser (1942?) 34.800tons 3x2 356mm

 

[jeffb]

Great stuff Tzoli!

 

[World B4]

This is going to be a long post!

Thanks a million for this!