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OK, here's a more serious attempt to compete for the second place after Charguizard has definitely carried this competition:
Yoshino-Class: Economy cruisers
By the time the European war had commenced, Japan had just started to rebuild her light cruiser fleet with the Agano class, of which eight were laid down in 1939 and 1940. For larger cruisers, the Japanese fleet wanted something that would not even pretend to observe any size limits, ordering four 30.000-ton Naniwa-class large cruisers with nine 305mm guns each and four 18.000-ton Ibuki-Class heavy cruisers with twelve 203mm guns each. Both heavy guns and engines (the former were to have 180.000 SHP for 34 knots) would prove production bottlenecks, and a March 1939 Admiral Staff study estimated that these vessels would not be available before 1944/5 – and even these late dates could only be met at the expense of aircraft carrier production. The study proposed postponing the Naniwas and cancelling the Ibukis in favour of a much smaller and less powerful type which could be armed with stockpiled guns and would be available in 1942/3. Admiral Yamamoto, who had no interest in any delays to the carrier programme (three Zuilaku- and three Taiho-class ships were to be laid down between 1938 and 1941 and completed within no more than three years per hull) strongly endorsed the proposal, and the four hulls were included in the 1939 programme.
The design was a straightforward downsize of the existing Tone-hull, with superstructure resembling a mix between Mogami (full-length shelter deck, aviation and torpedo arrangements) and Agano (Bridge and funnel shape, mast and crane arrangement). Although by that time the LNT was dead and buried, and the Japanese designers paid no regard to any size limits when drawing up this type, they came out at 9,970 tons standard more or less by coincidence; weights were calculated in a much more realistic fashion than previously, and the final plans were presented less than a month after the ministerial go-ahead. Engine power was reduced to 104.000 SHP for a design speed of 33 kts – a third less engine weight and space compared with Mogami, paid for with only two knots less speed, which struck everyone involved as a good deal – and range was calculated to be 10.000 nm at 14 knots. Armour protection consisted of an internal 100mm belt and a 50mm deck; the main guns had 120mm shields, 50mm sides and 70mm barbettes. Armament varied between the class ship and her three sisters: The first unit was equipped with 8 203mm Type 3 No.1 guns in four twin turrets; these turrets and their guns were less powerful than the newer weapons of the Mogamis and Tones, but they came free of charge, because they had been removed from the aircraft carriers Akagi and Amagi during their recent complete refits. Four twin 127mm DP guns, arranged as on Mogami, and six twin 25mm mounts completed the designed gunnery. Sixteen 609mm torpedo tubes in four quad mounts were added; no torpedo reloads were provided. Two catapults were installed, served by a single very large crane attached to the main mast. Three F1M aircraft could be carried, but only two in an assembled state. The class ship was named Yoshino and laid down in August 1939 at the Yokosuka Navy Yard, less than five months after the first proposal. By using material already stockpiled for the cancelled Ibuki-class, Yoshino could be completed in little more than three years and was commissioned in December 1942. Design speed was easily secured at regular full power; on flank speed trials, 34,05 knots were attained at 114.989 shp.
Yoshino used up all 203mm twin turrets still in stock; for her sisters, a lighter armament was provided. Of the 28 155mm triple turrets originally built for the Mogamis and Tones, 16 were to be re-used as secondary armament for the four Yamato-class battleships. The remaining 12 were earmarked for the other three Yoshino-Class ships; all other particulars were to remain as per the class ship. They were named Shirane (laid down in November 1939 by Mitsubishi at Nagasaki), Otowa (laid down June 1940 by the Kure Navy Yard) and Unebi (laid down August 1940 by Kawasaki at Kobe). Late in 1940, the decision was made to cut armament to three 155mm triples in Otowa and Unebi and replace their heavy flak by ten of the superb new 100mm/60 guns in five twin mounts; the two 155mm turrets were later issued to the new light cruiser Oyodo. The second pair also differed from the first two by more modern AA fire control (rangefinders with integral directors), the lack of the aft main director, which was replaced by an additional AA director, and a bulbous bow; the speed gain was however marginal. As construction proceeded, the decision was made to change Shirane’s armament likewise (approved May 1941); this was done when new calculations showed that Otowa and Unebi could be fitted with a 140mm belt and a 60mm deck due to the lower weight of their armament, resulting in a more balanced and survivable design. Turrets and barbettes were likewise up-armoured (140mm shields, 70mm sides, 120mm barbettes). These changes, which were implemented early in Otowa and Unebi without much loss of time, delayed Shirane’s completion and placed her last of her class when she was delivered in August 1944, after a construction time of nearly four years. Otowa was commissioned in October 1943, Unebi in December. By the time Otowa was ready, her 25mm twins had been replaced by triples, and a fourth pair of these was added for a total of 24 barrels; while Yoshino had been delivered without radars, the other three had Type 13 (one at the mainmast) and 22 (two abreast of the main director) radar from the outset.
Unebi was identical to Otowa when she was commissioned. Light flak on all ships was rapidly augmented; by late 1944, Unebi had received a total of 60 25mm barrels (17 triple mounts and 9 single mounts). She also now embarked new E16A floatplanes, whose number was reduced to 2.
Shirane differed from Otowa and Unebi by her older-fashioned fire control fit (she had AA directors with integral rangefinders, but only two of them, and retained the aft main gun director) and bow shape; her armament was identical. In 1945, she was fitted with an additional Type 21 radar in the foretop and a much enlargened radar office between bridge and foremast.
This quartet of cruisers was generally rated as very satisfactory; the only quibbles were the short space between the catapults and the mainmast, which made operating any floatplane bigger than the F1M difficult (the catapult had to be trained outward to 60° and the plane on the other catapult moved to its forward end in order to launch an E16A) and the lack of deckspace for even more light AA. Their two-knot speed deficit compared with older japanese cruisers usually was no problem, because their sustained sea speed was only marginally slower. Like all Japanese cruisers, they were indifferent sea boats due to their rather low freeboard, but under pacific conditions, this was not much of a problem either.
Although brief, war service of these ships was intense. Yoshino was present at the offensive against Fiji/New Caledonia and the bloody battle of Rotuma; she was one of the last IJN ships to escape from Truk and fought at Leyte with Nishimura’s squadron, where she was lost to US battleship gunnery after repulsing a destroyer attack and sinking an US destroyer; she was credited with another at New Caledonia. Shirane, the luckiest of the quartet, survived the war after sinking an US escort carrier and an escort destroyer at Leyte; she became a British prize and was scrapped in 1950 after use in various trials. Unebi and Otowa both were present in the battle of the Philippine Sea and accompanied Ozawa’s carriers at Leyte; Otowa was sunk by US carrier planes in that battle, Unebi escaped to Japan and was sunk in shallow water by US airstrikes in 1946.
For those who care: Springsharp for the heavy cruiser Version
Yoshino, Japan Heavy Cruiser laid down 1939
Displacement:
9.536 t light; 9.968 t standard; 11.059 t normal; 11.932 t full load
Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(634,19 ft / 623,36 ft) x 63,98 ft x (18,70 / 19,83 ft)
(193,30 m / 190,00 m) x 19,50 m x (5,70 / 6,04 m)
Armament:
8 - 7,99" / 203 mm 50,0 cal guns - 270,21lbs / 122,57kg shells, 120 per gun
Breech loading guns in turret on barbette mounts, 1939 Model
4 x 2-gun mounts on centreline ends, evenly spread
8 - 5,00" / 127 mm 50,0 cal guns - 66,16lbs / 30,01kg shells, 200 per gun
Anti-air guns in deck and hoist mounts, 1939 Model
4 x Twin mounts on sides, forward evenly spread
18 - 0,98" / 25,0 mm 72,0 cal guns - 0,54lbs / 0,24kg shells, 1.500 per gun
Machine guns in deck mounts, 1939 Model
6 x Triple mounts on side ends, majority forward
Weight of broadside 2.701 lbs / 1.225 kg
Main Torpedoes
16 - 24,0" / 609 mm, 26,25 ft / 8,00 m torpedoes - 2,220 t each, 35,513 t total
In 4 sets of deck mounted side rotating tubes
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 3,94" / 100 mm 437,99 ft / 133,50 m 9,61 ft / 2,93 m
Ends: Unarmoured
Main Belt covers 108% of normal length
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 4,70" / 120 mm 1,97" / 50 mm 2,76" / 70 mm
2nd: 1,97" / 50 mm 0,79" / 20 mm -
- Protected deck - single deck:
For and Aft decks: 1,97" / 50 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 104.000 shp / 77.584 Kw = 33,23 kts
Range 10.000nm at 14,00 kts
Bunker at max displacement = 1.963 tons
Complement:
538 - 700
Cost:
£5,879 million / $23,516 million
Distribution of weights at normal displacement:
Armament: 875 tons, 7,9%
- Guns: 804 tons, 7,3%
- Weapons: 71 tons, 0,6%
Armour: 1.746 tons, 15,8%
- Belts: 672 tons, 6,1%
- Armament: 266 tons, 2,4%
- Armour Deck: 808 tons, 7,3%
Machinery: 2.814 tons, 25,4%
Hull, fittings & equipment: 3.951 tons, 35,7%
Fuel, ammunition & stores: 1.523 tons, 13,8%
Miscellaneous weights: 150 tons, 1,4%
- On freeboard deck: 100 tons
- Above deck: 50 tons
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
12.100 lbs / 5.488 Kg = 47,4 x 8,0 " / 203 mm shells or 0,9 torpedoes
Stability (Unstable if below 1.00): 1,26
Metacentric height 3,9 ft / 1,2 m
Roll period: 13,6 seconds
Steadiness - As gun platform (Average = 50 %): 45 %
- Recoil effect (Restricted arc if above 1.00): 0,38
Seaboat quality (Average = 1.00): 0,79
Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0,519 / 0,528
Length to Beam Ratio: 9,74 : 1
'Natural speed' for length: 24,97 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 23,00 degrees
Stern overhang: 0,00 ft / 0,00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20,00%, 25,52 ft / 7,78 m, 17,39 ft / 5,30 m
- Forward deck: 30,00%, 17,39 ft / 5,30 m, 16,99 ft / 5,18 m
- Aft deck: 35,00%, 16,99 ft / 5,18 m, 16,99 ft / 5,18 m
- Quarter deck: 15,00%, 16,99 ft / 5,18 m, 14,50 ft / 4,42 m
- Average freeboard: 17,60 ft / 5,36 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 106,1%
- Above water (accommodation/working, high = better): 159,1%
Waterplane Area: 27.039 Square feet or 2.512 Square metres
Displacement factor (Displacement / loading): 108%
Structure weight / hull surface area: 111 lbs/sq ft or 540 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1,00
- Longitudinal: 1,03
- Overall: 1,00
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather
And Springsharp for the light cruiser version:
Unebi, Japan Light Cruiser laid down 1940
Displacement:
9.596 t light; 9.978 t standard; 11.059 t normal; 11.924 t full load
Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(634,19 ft / 623,36 ft) x 63,98 ft x (18,70 / 19,82 ft)
(193,30 m / 190,00 m) x 19,50 m x (5,70 / 6,04 m)
Armament:
9 - 6,10" / 155 mm 60,0 cal guns - 124,45lbs / 56,45kg shells, 150 per gun
Breech loading guns in turret on barbette mounts, 1940 Model
3 x 3-gun mounts on centreline ends, majority forward
10 - 3,94" / 100,0 mm 65,0 cal guns - 33,83lbs / 15,35kg shells, 300 per gun
Anti-air guns in deck and hoist mounts, 1940 Model
4 x Twin mounts on sides, forward evenly spread
1 x Twin mount on centreline, aft deck centre
1 raised mount
24 - 0,98" / 25,0 mm 72,0 cal guns - 0,54lbs / 0,24kg shells, 1.500 per gun
Machine guns in deck mounts, 1940 Model
8 x Triple mounts on sides, evenly spread
6 raised mounts
Weight of broadside 1.471 lbs / 667 kg
Main Torpedoes
16 - 24,0" / 609 mm, 26,25 ft / 8,00 m torpedoes - 2,220 t each, 35,513 t total
In 4 sets of deck mounted side rotating tubes
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5,51" / 140 mm 437,99 ft / 133,50 m 9,61 ft / 2,93 m
Ends: Unarmoured
Main Belt covers 108% of normal length
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 5,51" / 140 mm 2,76" / 70 mm 4,72" / 120 mm
2nd: 1,97" / 50 mm 0,79" / 20 mm -
- Protected deck - single deck:
For and Aft decks: 2,36" / 60 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 104.000 shp / 77.584 Kw = 33,23 kts
Range 10.000nm at 14,00 kts
Bunker at max displacement = 1.946 tons
Complement:
538 - 700
Cost:
£5,493 million / $21,972 million
Distribution of weights at normal displacement:
Armament: 609 tons, 5,5%
- Guns: 538 tons, 4,9%
- Weapons: 71 tons, 0,6%
Armour: 2.204 tons, 19,9%
- Belts: 944 tons, 8,5%
- Armament: 291 tons, 2,6%
- Armour Deck: 970 tons, 8,8%
Machinery: 2.781 tons, 25,1%
Hull, fittings & equipment: 3.852 tons, 34,8%
Fuel, ammunition & stores: 1.463 tons, 13,2%
Miscellaneous weights: 150 tons, 1,4%
- On freeboard deck: 100 tons
- Above deck: 50 tons
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
14.031 lbs / 6.364 Kg = 123,5 x 6,1 " / 155 mm shells or 1,0 torpedoes
Stability (Unstable if below 1.00): 1,29
Metacentric height 4,0 ft / 1,2 m
Roll period: 13,4 seconds
Steadiness - As gun platform (Average = 50 %): 45 %
- Recoil effect (Restricted arc if above 1.00): 0,21
Seaboat quality (Average = 1.00): 0,83
Hull form characteristics:
Hull has a flush deck,
a straight bulbous bow and a cruiser stern
Block coefficient (normal/deep): 0,519 / 0,528
Length to Beam Ratio: 9,74 : 1
'Natural speed' for length: 24,97 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 23,00 degrees
Stern overhang: 0,00 ft / 0,00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20,00%, 25,52 ft / 7,78 m, 17,39 ft / 5,30 m
- Forward deck: 30,00%, 17,39 ft / 5,30 m, 16,99 ft / 5,18 m
- Aft deck: 35,00%, 16,99 ft / 5,18 m, 16,99 ft / 5,18 m
- Quarter deck: 15,00%, 16,99 ft / 5,18 m, 14,50 ft / 4,42 m
- Average freeboard: 17,60 ft / 5,36 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 97,9%
- Above water (accommodation/working, high = better): 159,1%
Waterplane Area: 27.039 Square feet or 2.512 Square metres
Displacement factor (Displacement / loading): 114%
Structure weight / hull surface area: 104 lbs/sq ft or 509 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1,02
- Longitudinal: 0,99
- Overall: 1,00
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather
Greetings
GD