Washington Naval Treaty Centennial Challenge

[maomatic]

The Magdeburg-class heavy cruiser is based on the premise, that there were none of the historical quarrels between the K-Amt ("construction office") and the Marine-Ausbildungsabteilung A IV ("training departement") during the planning stages of the M-class cruiser. My premise also relies on the Marinewaffenamt ("artillery office") suddenly developing a preference for triple turrets and pushing for a (actually proposed) calibre increase to 17cm, which is totally not stretching it...

So this is basically a beefed-up M-class with heavier armour, 3x3 17cm main guns and improved AA-armament at the cost of reduced speed.

It is designed to be faster than (most) potential enemy (France/GB/Soviet) CAs, while being better armoured and armed than faster CLs. In addition, its mixed Diesel/Turbine propulsion should enable it to have decent enough range to carry out operations into the Atlantic.

Code: Select all

Dresden, Germany Heavy Cruiser laid down 1937

Displacement:
	9.639 t light; 10.000 t standard; 11.114 t normal; 12.005 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
	(639,99 ft / 614,50 ft) x 67,59 ft x (21,33 / 22,51 ft)
	(195,07 m / 187,30 m) x 20,60 m  x (6,50 / 6,86 m)

Armament:
      9 - 6,81" / 173 mm 50,0 cal guns - 167,24lbs / 75,86kg shells, 120 per gun
	  Breech loading guns in turret on barbette mounts, 1936 Model
	  1 x Triple mount on centreline, aft deck aft
	  2 x Triple mounts on centreline, forward deck forward
		1 raised mount - superfiring
      10 - 3,46" / 88,0 mm 65,0 cal guns - 23,06lbs / 10,46kg shells, 200 per gun
	  Dual purpose guns in deck and hoist mounts, 1933 Model
	  4 x Twin mounts on sides, evenly spread
		2 raised mounts
	  1 x Twin mount on centreline, aft deck aft
		1 raised mount
      8 - 1,46" / 37,0 mm 60,0 cal guns - 1,70lbs / 0,77kg shells, 1.200 per gun
	  Anti-air guns in deck mounts, 1936 Model
	  8 x Single mounts on sides, evenly spread
		4 raised mounts
      13 - 0,79" / 20,0 mm 65,0 cal guns - 0,26lbs / 0,12kg shells, 2.000 per gun
	  Anti-air guns in deck mounts, 1930 Model
	  9 x Single mounts on sides, evenly spread
		4 raised mounts
	  2 x Twin mounts on centreline ends, evenly spread
		1 raised mount - superfiring
      Weight of broadside 1.753 lbs / 795 kg
      Main Torpedoes
      6 - 21,0" / 533 mm, 23,50 ft / 7,16 m torpedoes - 1,576 t each, 9,455 t total
	In 2 sets of deck mounted side rotating tubes

Armour:
   - Belts:		Width (max)	Length (avg)		Height (avg)
	Main:	3,94" / 100 mm	399,44 ft / 121,75 m	9,84 ft / 3,00 m
	Ends:	0,98" / 25 mm	  65,62 ft / 20,00 m	6,56 ft / 2,00 m
	  149,44 ft / 45,55 m Unarmoured ends
	  Main Belt covers 100 % of normal length
	  Main belt does not fully cover magazines and engineering spaces  

   - Torpedo Bulkhead - Additional damage containing bulkheads:
		1,18" / 30 mm	399,44 ft / 121,75 m	9,84 ft / 3,00 m
	Beam between torpedo bulkheads 61,02 ft / 18,60 m

   - Gun armour:	Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
	Main:	4,72" / 120 mm	2,36" / 60 mm		3,94" / 100 mm
	2nd:	0,39" / 10 mm	      -			0,79" / 20 mm

   - Protected deck - multiple decks:
	For and Aft decks: 2,36" / 60 mm
	Forecastle: 0,00" / 0 mm  Quarter deck: 1,18" / 30 mm

   - Conning towers: Forward 3,94" / 100 mm, Aft 0,79" / 20 mm

Machinery:
	Oil fired boilers, steam turbines,  plus diesel motors, 
	Geared drive, 3 shafts, 100.000 shp / 74.600 Kw = 33,10 kts
	Range 7.500nm at 16,00 kts
	Bunker at max displacement = 2.005 tons

Complement:
	540 - 703

Cost:
	£5,004 million / $20,015 million

Distribution of weights at normal displacement:
	Armament: 483 tons, 4,3 %
	   - Guns: 465 tons, 4,2 %
	   - Weapons: 19 tons, 0,2 %
	Armour: 2.153 tons, 19,4 %
	   - Belts: 653 tons, 5,9 %
	   - Torpedo bulkhead: 172 tons, 1,5 %
	   - Armament: 282 tons, 2,5 %
	   - Armour Deck: 997 tons, 9,0 %
	   - Conning Towers: 51 tons, 0,5 %
	Machinery: 2.772 tons, 24,9 %
	Hull, fittings & equipment: 4.231 tons, 38,1 %
	Fuel, ammunition & stores: 1.475 tons, 13,3 %
	Miscellaneous weights: 0 tons, 0,0 %

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  13.411 lbs / 6.083 Kg = 84,9 x 6,8 " / 173 mm shells or 1,7 torpedoes
	Stability (Unstable if below 1.00): 1,13
	Metacentric height 3,5 ft / 1,1 m
	Roll period: 15,2 seconds
	Steadiness	- As gun platform (Average = 50 %): 70 %
			- Recoil effect (Restricted arc if above 1.00): 0,34
	Seaboat quality  (Average = 1.00): 1,07

Hull form characteristics:
	Hull has a flush deck,
	  a normal bow and a cruiser stern
	Block coefficient (normal/deep): 0,439 / 0,449
	Length to Beam Ratio: 9,09 : 1
	'Natural speed' for length: 24,79 kts
	Power going to wave formation at top speed: 56 %
	Trim (Max stability = 0, Max steadiness = 100): 66
	Bow angle (Positive = bow angles forward): 26,30 degrees
	Stern overhang: 12,00 ft / 3,66 m
	Freeboard (% = length of deck as a percentage of waterline length):
				Fore end,	 Aft end
	   - Forecastle:	20,00 %,  27,30 ft / 8,32 m,  18,50 ft / 5,64 m
	   - Forward deck:	30,00 %,  18,50 ft / 5,64 m,  17,49 ft / 5,33 m
	   - Aft deck:	35,00 %,  17,49 ft / 5,33 m,  18,50 ft / 5,64 m
	   - Quarter deck:	15,00 %,  18,50 ft / 5,64 m,  21,00 ft / 6,40 m
	   - Average freeboard:		19,06 ft / 5,81 m

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 107,5 %
		- Above water (accommodation/working, high = better): 163,3 %
	Waterplane Area: 26.264 Square feet or 2.440 Square metres
	Displacement factor (Displacement / loading): 117 %
	Structure weight / hull surface area: 111 lbs/sq ft or 542 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 0,96
		- Longitudinal: 1,35
		- Overall: 1,00
	Adequate machinery, storage, compartmentation space
	Excellent accommodation and workspace room
	Ship has slow, easy roll, a good, steady gun platform

[StealthJester]

Iya class battleships:


Nusantara’s participation in the Washington Naval Conference of 1921-22 was the direct result of a Japanese plan to stifle her long-time rival’s naval expansion which was now perceived as a threat to the Empire’s ambitions in the Pacific – albeit a lesser one than posed by the United States or Britain.
However, these efforts were derailed at the conference itself. Japan immediately pushed for Nusantara to have parity with France and Italy at a ratio of 1.7, whereas the US and the UK wanted Nusantara to have parity with Japan. After weeks of heated debate a compromise was reached; Nusantara was allowed a ratio of 2.3, which equaled 244,000 metric tons for capital ships compared to Japan’s allowance of 320,000 metric tons. However, the big win for Nusantara was the provision allowing the country to complete the Lewotobi class, which was currently under construction, in order to meet treaty limits, which of course did nothing to mollify the Japanese and further strained already poor relations with Nusantara.

After the so-called “building holiday” established by the Treaty expired in late 1931, the Nusantaran Admiralty issued specifications for a new class of battleship to replace the Kerinci class battleships and the now thoroughly obsolete Toba class semi-dreadnoughts which were nearing their twentieth year in service and thus eligible for replacement. A number of designs were created between 1932 and 1934 in keeping to the Treaty displacement limits of 35,560 metric tons armed with eight to twelve 343mm (13.5”) guns. The Admiralty wasn’t satisfied with these designs, however, as Japan already fielded two battleships with 16” guns and eight with 14” guns. New specifications were issued in 1935 for ships with a heavier main battery.

As it transpired, the solution was already at hand. Back in 1920, as work began on what would be the Lewotobi class, the KNM purchased several British 15” Mk I guns originally intended for now-cancelled members of the Queen Elizabeth and Royal Sovereign classes as evaluation weapons. As part of this process, the Nationale Bewapeningswerken (National Armament Works or NB) took one of the guns and over-bored it to 393mm (15.5”), designating it the 393mm/40 Mk I. Work had continued on this weapon and by 1935 the NB was confident a 45-caliber variant could be produced to arm the new ships.
This revised program hit a snag when Nusantara, along with the US, Britain, and France, signed the 1936 London Naval Treaty which maintained the Washington Treaty 35,000 ton displacement limit, but also limited maximum gun size to 14” (356mm), which required another revision to the design by swapping the proposed 393mm’s for up-rated 343mm/50 Mk III guns. This change delayed the start of construction until late 1937. However, Japan’s refusal to sign the 1936 London Treaty triggered the escalation clause allowing up to 16” (406mm) guns. Nusantara immediately swapped out the planned quad 343mm turrets for triple mounts with the new 393mm/45 Mk IV – made possible when the designers, suspecting the Japanese wouldn’t sign the treaty, ensured the turret base rings were the same diameter for both mounts (a similar change occurred in the US when the 14” guns intended for the North Carolina class were swapped for new design 16” weapons).

The first ship in the class, Iya, was laid down in October of 1937, followed by four sister-ships; Talakmau, Masurai, Kunyit, and Imun, over the next two years. Iya and Talakmau were in service when war with Japan broke out in July of 1941, and Kunyit commissioned by early 1942. Construction had lagged on the other two ships as war approached however, and both were cancelled in December of 1941, soon after broken up on the slipways to free up space for the Emergency Carrier Program. Commissioned initially without radar and with an outdated battery of 75mm AA guns, the three ships completed were quickly equipped with British radars, fire-control systems, and modern license-built 40mm and 20mm anti-aircraft weapons.

The Iya class, although slightly outgunned by the Japanese Nagato class and severely outgunned by the Yamatos’, nevertheless gave a good accounting of themselves. Talakmau was lost in April of 1943 to an air-strike from the Japanese carriers Shokaku and Zuikaku off Formosa, but Iya and Kunyit, although damaged on several occasions, survived the war. Kunyit’s crowning moment was undoubtedly in August of 1945 when, along with the newer Ijen, she fought the Yamato off Okinawa. By approaching from opposite sides of the Japanese giant and keeping the range open, the two Nusantaran battlewagons showered the Yamato with over a hundred 393mm AP and HE rounds, which, although failing to sink her, severely damaged the superstructure, fire-control gear, most of the secondary battery, and wrecked the funnel uptakes and several boilers, forcing the crippled battleship to be taken under tow. Both Nusantaran ships were damaged in the encounter - Kunyit severely - but were later repaired and returned to service. Yamato would be torpedoed and sunk two days later by the Cavalerie (O-162), a Jimpul class submarine, before she could reach Japan.

After the war ended in September of 1946, the Iya class continued in active service until placed in reserve in 1962. Iya was scrapped four years later, but Kunyit became a museum ship and can still be visited today.

In class: (3+2) Iya, Talakmau, Maurai (cancelled incomplete 1941, scrapped), Kunyit, Imun (cancelled incomplete 1941, scrapped)

Built: 1937-1942

In commission: 1940-1962

Displacement: 35,200 ts standard, 38,820 ts full load

Dimensions: Length (o/a) 225.0m, length (w/l) 220.0m, beam 32.5m, draft (normal) 9.5m

Propulsion: 4-shaft, 4 x SKR geared turbines, 16 x HeV oil-fired boilers; 94,500 shp

Performance: 27.0 knots

Range: 12,000 nm at 12 knots

Armor: Belt 350mm tapering to 100mm ends, deck 145-120mm, main turrets 380-200mm, main barbettes 360mm, secondary turrets 50-25mm, torpedo bulkhead 30mm, forward conning tower 350mm, aft conning tower 50mm

Armament: 9 (3 x 3) NB 393mm/45 Mk IV, 16 (8 x 2) NB 114mm/45 Mk II; original AA battery: 8 x NB 75mm HA Mk VII; AA battery by January of 1945: 60 x NB 40mm AA Mk I (8 x 4, 14 x 2), 48 x NB 20mm AA Mk I (6 x 4, 12 x 2); 2-3 Royer V1R Meeuw scout floatplanes (replaced by 1944 by Royer V3R Albatros)

Sensors/Electronics: Type 273 surface-search radar, Type 277 air/surface search radar, Type 281 air-search radar, 2 x Type XX 5-meter fire control directors; 4 x Type A-III (license-built British HACS) anti-aircraft fire control directors

Crew: 1,338-1,750

Cheers!
Stealthjester

[Idunevenknow]

Sconosciuto Class Cruiser

Main armament: 4x2 152mm
Secondary Armament: 6x1 100mm

AA: 4x1 20mm/2x2 40mm

Very speeby; ~ 35 knots

[BurnedBread17]

Rosenberg Class Battleship


KSS Rosenberg, January 1338.

Note; The date is in AU timeline. 1338 is equivalent to real world 1936. (Add 598 years to get the real world's date)

The Rosenberg Class Battleships were a series of 3 battleships laid down 2 years after the 10 year Battleship Holiday of the Evinheim Naval Treaty which was signed in 1323 (AU version of Washington Naval Treaty). The Rosenbergs was built to replace the ageing Siegmarian Great War battleships with the Evinheim Naval Treaty in mind. They are equipped with 3, triple 15 inch gun for the main armament. For the secondaries, they are equipped with 10, dual purpose 5 inch gun. They were the largest battleship in Aemore at the time, later succeeded by another class of Siegmarian battleship.

The first ship of the class, Rosenberg, was laid down in May 1334. She was launched in December 1335 and commisioned in January 1337.

Ships in Class

Rosenberg - Sunk in action, 1347
Königsland - Sunk in action, 1347
Ritterberg - Surrendered to Desnia, 1348

Code: Select all

Project C, Siegmaria Battleship laid down 1935 (Engine 1936)

Displacement:
	32 260 t light; 34 707 t standard; 36 665 t normal; 38 231 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
	(807,24 ft / 787,40 ft) x 98,43 ft x (32,15 / 33,20 ft)
	(246,05 m / 240,00 m) x 30,00 m  x (9,80 / 10,12 m)

Armament:
      9 - 15,00" / 381 mm 50,0 cal guns - 1 786,45lbs / 810,32kg shells, 175 per gun
	  Breech loading guns in turret on barbette mounts, 1935 Model
	  3 x Triple mounts on centreline ends, majority forward
		1 raised mount - superfiring
      20 - 5,04" / 128 mm 45,0 cal guns - 64,53lbs / 29,27kg shells, 210 per gun
	  Dual purpose guns in deck mounts, 1935 Model
	  10 x Twin mounts on sides, evenly spread
		4 raised mounts
      Weight of broadside 17 369 lbs / 7 878 kg

Armour:
   - Belts:		Width (max)	Length (avg)		Height (avg)
	Main:	12,6" / 320 mm	462,60 ft / 141,00 m	11,91 ft / 3,63 m
	Ends:	Unarmoured
	Upper:	5,51" / 140 mm	462,60 ft / 141,00 m	8,01 ft / 2,44 m
	  Main Belt covers 90 % of normal length
	  Main Belt inclined 45,00 degrees (positive = in)

   - Torpedo Bulkhead - Additional damage containing bulkheads:
		1,77" / 45 mm	462,60 ft / 141,00 m	28,71 ft / 8,75 m
	Beam between torpedo bulkheads 75,46 ft / 23,00 m

   - Hull void:
		0,00" / 0 mm	  0,00 ft / 0,00 m	0,00 ft / 0,00 m

   - Gun armour:	Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
	Main:	14,2" / 360 mm	7,87" / 200 mm		13,8" / 350 mm
	3rd:	0,98" / 25 mm	0,98" / 25 mm		      -

   - Armoured deck - multiple decks:
	For and Aft decks: 4,33" / 110 mm
	Forecastle: 2,36" / 60 mm  Quarter deck: 3,15" / 80 mm

   - Conning towers: Forward 13,78" / 350 mm, Aft 5,91" / 150 mm

Machinery:
	Oil fired boilers, steam turbines, 
	Geared drive, 3 shafts, 90 122 shp / 67 231 Kw = 27,00 kts
	Range 7 100nm at 15,00 kts
	Bunker at max displacement = 3 524 tons

Complement:
	1 324 - 1 722

Cost:
	£16,342 million / $65,368 million

Distribution of weights at normal displacement:
	Armament: 3 164 tons, 8,6 %
	   - Guns: 3 164 tons, 8,6 %
	Armour: 12 030 tons, 32,8 %
	   - Belts: 3 854 tons, 10,5 %
	   - Torpedo bulkhead: 871 tons, 2,4 %
	   - Armament: 2 938 tons, 8,0 %
	   - Armour Deck: 3 900 tons, 10,6 %
	   - Conning Towers: 468 tons, 1,3 %
	Machinery: 2 529 tons, 6,9 %
	Hull, fittings & equipment: 14 412 tons, 39,3 %
	Fuel, ammunition & stores: 4 405 tons, 12,0 %
	Miscellaneous weights: 125 tons, 0,3 %
	   - Hull below water: 25 tons
	   - Hull void weights: 25 tons
	   - Hull above water: 25 tons
	   - On freeboard deck: 25 tons
	   - Above deck: 25 tons

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  50 298 lbs / 22 815 Kg = 29,8 x 15,0 " / 381 mm shells or 7,9 torpedoes
	Stability (Unstable if below 1.00): 1,00
	Metacentric height 4,9 ft / 1,5 m
	Roll period: 18,7 seconds
	Steadiness	- As gun platform (Average = 50 %): 80 %
			- Recoil effect (Restricted arc if above 1.00): 1,00
	Seaboat quality  (Average = 1.00): 1,37

Hull form characteristics:
	Hull has a flush deck,
	  a straight bulbous bow and a round stern
	Block coefficient (normal/deep): 0,515 / 0,520
	Length to Beam Ratio: 8,00 : 1
	'Natural speed' for length: 28,06 kts
	Power going to wave formation at top speed: 44 %
	Trim (Max stability = 0, Max steadiness = 100): 58
	Bow angle (Positive = bow angles forward): 18,00 degrees
	Stern overhang: 9,84 ft / 3,00 m
	Freeboard (% = length of deck as a percentage of waterline length):
				Fore end,	 Aft end
	   - Forecastle:	21,00 %,  30,77 ft / 9,38 m,  25,20 ft / 7,68 m
	   - Forward deck:	30,00 %,  25,20 ft / 7,68 m,  19,59 ft / 5,97 m
	   - Aft deck:	31,00 %,  19,59 ft / 5,97 m,  19,59 ft / 5,97 m
	   - Quarter deck:	18,00 %,  19,59 ft / 5,97 m,  19,59 ft / 5,97 m
	   - Average freeboard:		22,07 ft / 6,73 m
	Ship tends to be wet forward

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 88,0 %
		- Above water (accommodation/working, high = better): 157,9 %
	Waterplane Area: 52 351 Square feet or 4 864 Square metres
	Displacement factor (Displacement / loading): 109 %
	Structure weight / hull surface area: 204 lbs/sq ft or 998 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 0,97
		- Longitudinal: 1,32
		- Overall: 1,00
	Adequate machinery, storage, compartmentation space
	Excellent accommodation and workspace room
	Ship has slow, easy roll, a good, steady gun platform
	Good seaboat, rides out heavy weather easily

[alternathistory]

Ragnar Lodbrok-class battleship. Scandinavian Empire

The main difference between this world and ours is the death of Genghis Khan during the conquest of Khorezm. This event changed history dramatically. Among other things, the Hundred Years War ended with the conquest of England by France. And this led to the fact that England never became a great power. Denmark took its place.
Initially, through dynastic marriages, Denmark received some small enclaves-colonies in the British Isles and in France, on the Brittany Peninsula. This made it possible to take control of all trade in the Baltic and the North Sea and crush the Hanseatic League. Further, by means of dynastic marriages, the Danes united Scandinavia under one crown. And during the religious wars, annex the north of Germany. Scandinavia did not have large colonial possessions in the world, however, small colonies-trading posts were scattered around the globe, which made it possible to conduct successful trade.
In this form, Scandinavia approached the 20th century. To protect her maritime empire, she had to create and maintain a powerful fleet, which included ships of all classes, including battleships.
In 1922, in order to curb the arms race at sea in this world, an agreement was concluded - a complete analogue of our Washington Treaty. And for the next 20 years, all warships were built according to the parameters of this agreement, including in the Scandinavian Empire.
The Ragnar Lothbrok-class battleship was laid down in 1924. The series consisted of four ships named after the famous Vikings:
• Ragnar Lodbrok,
• Bjorn Ironside,
• Sigurd the Serpent-Eyed,
• Ivar the Boneless.
They had the following specifications:
Displacement;
• Standard — 34,000 tons,
• Complete — 38,000 tons,
Dimensions;
• Length - 220 m,
• Width 33 m,
• Draft 9 m,
Booking;
• Belt - 300 mm,
• Bow beams — 200 mm;
• Stern beams - 200 mm;
• Deck - 100 mm;
• Forehead of GK towers - 350 mm,
• Board and rear of the GK towers - 250 mm,
• Roof of GK towers - 100 mm;
• Barbettes of GK towers - 350 mm;
• Towers of medium caliber - 30 mm,
• Barbets towers SK - 25 mm;
• Cutting - 350 mm,
• Cabin roof - 165 mm.
Power point;
• Machinery - 2 steam turbines,
• Power - 45,000 liters. With.,
• Maximum travel speed - 22.5 knots,
• Cruising range - 7000 nautical miles at 16 knots,
Armament;
• Main caliber - 3 × 3 × 400 mm,
• Medium caliber - 6 × 2 × 146 mm and 2x1x146 mm,
• Short-range anti-aircraft guns - 7 × 8 × 20 mm,
• Mine and torpedo armament - 2 × 1 × 620-mm torpedo tubes,
• Air group - 1 catapult, 1 seaplane.
Crew - 1300 people.

[Shiki]

Lucaelian cruiser Scorpius, October 1935.

Built: 1929-1935
Commission: 1934-1958

By the late 1920s, the naval arms race had evolved in ways few could have predicted: the aging battleships of the major powers, for the most part limited to 21-24 knots, had long since been outstripped by a new generation of flotilla craft and powerful new first-class cruisers armed with 203 mm guns. It would be developments with the latter that spurred Lucaelian construction efforts: the first two ships of the Italian Zara class would be authorized in 928, powerfully armed and armoured cruisers capable of 32 kts. With more due to be authorized in the coming years and a French response inevitable, the Lucaelians would step into action themselves.

Scorpius would be the last of the three Constellation-class cruisers, and the last Lucaelian heavy cruiser built to the terms of the Washington Treaty. Envisioned from the outset as a squadron flagship, the remaining nine cruisers - there was a basic assumption that two would be in refit or repair at any one time - fighting as three squadrons of three, she would be extensively remodelled compared to her sisters, accepting a pole mast and built-up superstructure in place of her sisters' tripods. Like her sisters, she was quite heavily armed for her size: nine 20 cm guns in three triple turrets, with two wing 10 cm HA mounts and a pair superfiring aft. Her standout feature, however, was her torpedo armament: a total of twelve tubes, an impressive number for a ship of this size. Nominally capable of 34 kts in calm conditions, she could still run at 32 for long periods in the rough waters of the northern Atlantic: the amount of water this could generate over the bow necessitated enclosing the 10 cm mountings.

The protection of these cruisers was their genesis: the increased weight that could be devoted to it over preceding ships, bought from lightweight machinery and superheated steam boilers, made them very heavily armoured compared to most cruisers elsewhere. The single strake of cemented plates was comprised of two separate thicknesses and heights: over the machinery and forward magazines, it was 4.11 metres in height, and varied between 100 and 125 mm in thickness respectively: over the after magazines it decreased to 2.74 metres in height, increasing again to 125 mm. It was closed by nickel steel bulkheads that were 95 mm thick forward and 60 mm aft. The main armour deck was 50 mm thick over the central 6.9 metres of the machinery: outboard of this it decreased to 30 mm. Over the magazines the outboard thickness was 50 mm, and the central thickness 70 mm. The turrets were protected with 140 mm faces, 70 mm roofs, 30 mm rears and 44 mm sides; the barbettes were 100 mm thick for No.2 and No.3 turrets, decreasing to 75 mm for No.1 turret.

Basic characteristics of Scorpius as completed:
All dimensions and displacements in metric unless otherwise noted.
Displacement:

• Standard — 10,160 t

• Trial — 11,680 t

• Load — 13,400 t

Speed & Endurance:

• Trials speed — 34.25 kts

• Service speed — 32.50 kts

• Cruising endurance — 9,840 nm @ 16 kts, 3,575 nm @ 28 kts

Armament:

• 3xIII — 20 cm/53 M.1923: 134.91 kg shell (APC, SAPC, HE) @ 895 m/sec, max. range 30 km.

• 4xII — 10 cm/50 M.1928: 16.05 kg shell (HE-AA, Starshell) @ 880 m/sec, max. range 18 km.

• 4xII — 3.5 cm AA M.1927

• 8xI — 18.5 mm HMG

• 4xIII — 53.5 cm M.1926 TT: 250 kg TNT warhead, max. range 20 km @ 34 kts (oxygen-enriched).

• 1x — RS.29 reconnaissance aircraft
  
  Protection:
  • Belt over machinery — 100 mm
  • Belt over magazines — 125 mm
  • Deck — 50-70 mm
  • Turret faces — 140 mm
  • CT — 140 mm

[waritem]

The two-faced cajuns

As the US threat seemed to definitively vanish with the alongside fight of first word war, the louisiana navy didn't felt the need of modernising its fleet for the next decade.
Netherless, the two battlecruiser inherited from the last naval arm race remained very expensive to maintain and gluttonous in human resources. Plans to replace them with 3 smaller more modern ships were lengering since the middle twenties.
The international tensions growth in the early 1930s allowed the release of the funds necessary for this project. To get the most out of this new class, the focus has been on versatility.
Therefore, the flight deck cruiser concept studied at that time by the US navy dragged the cajun attention.They asked the french STCN (Service technique des constructions navales), their usual designer, to conceive a simillar ship. The result was what they called a " croiseur d'aviation".
As they were planned to be the new lead ships of the navy, they couldn't be satisfied with a light cruiser weaponry like their american cousin in being. Without reaching the firepower of the hybrid battleships envisaged by several major navies, the caliber of the main guns was increased to 203mm, the maximum authorized for a first class cruiser. The Louisianans being already familiar with the quadruple turrets on their actuals capital ships, the design was naturally adopted for the new ones. Two mounts of this type made it possible to group fore the firepower typically found on a contemporary heavy cruiser The secondary battery consists of twelve 138.6 mm Model 1927 guns in twin turrets completed by six 100mm Model 1930 twin shielded monts and six 37mm Model 1925 semi-automatic guns for anti-aircraft duty, all divided between port and starboard sides.
Aviation facilitie was rejected at the back of the ship and was able to sustain 24 aircrafts. Unexperienced with onboard takeoff and landing, naval aviation officers pushed for a flushdeck design to avoid any obstacles in the planes trajectories, therefore the navigating and control bridge was located just under the forward lip of the flight deck. But gunnery officers asked for the highest position for the fire directors, so a conning tower was erected on the starboard. This annihilated the "gains" of the previous point, to solace the formers officers an aviation bridge was implemented at the back of it.
The result was quite odd, as the the navigation bridge was at a rather uncomfortable location, low behind the raised B turret. Concretely, most of the time (even in bad weather) the ship was commendered from the flying bridge, at the same level as the flight deck.

Two groups of Rateau turbine from Chantiers de Bretagne and four Indret boilers provided 105 000 hp securing a 33 knots speed. The french designers were unsatisfied with the cooling system they implemented on the Béarn. Refusing to abandon it completly, they opted for the same hybrid layout as the cretans who combined it with a japaneses style funnel stretching along the structure. In consequences the starboard gunnery had to be raised one bridge up.

Unusually, conscious that french shipborne aviation experience was limited, Louisianans opted for US sourced aircrafts. Grumman F3F were chosen as standard figther and Vought SB2U Vindicator as bomber. As only two flights could be carried by a single ship, the last one was modified to be able to fulfill both dive-bombing and torpedo-bombing.

The Lead-ship Saint-Louis, was officially commissionned on the 17 febrary 1937 (Louisianna republic national day) in New Orleans. Its airgroup consited only of figthers fligths (3-VFC and 5VFC) as vindicators weren't yet delivered. There was a polemic about it's naming, nationalists extremists of the Cajuns League claimed it as a support to their (unrealistic) will to gain the former territories of the old french louisianna (Saint-Louis was its former capital city).On the other side of the border, US irredentists who saught to regain Louisianna, tried to use it to demonstrate the danger of an independent french republic . In fact the three ships of the class were simply named after french sovereigns (the two others being Charlemagne and Charles Martel).

First exercices with the"loulou" (nickname of the ship), gained him the reputation of an unstable take-off and landing platform. It was reviled latter that unexperienced cajuns pilot, used to land fields, would have found any aircraft carrier unstable. Neverless construction of the two others units were delayed to solve this "issue". They were commissionned only in the early month of 1939 with the addition of bulges and an increased powerplant to maintain the same speed. Therefore they exided the treaty limitations, which at that time was no more a concern.

When France decleared war on Germany, Louisianna naturally followed its historical ally. Louisianna army was unprepared for modern war so training and equip an expeditionnary force took too long to be effective before the collapse of France. The main contribution was the navy who patrolled north and south atlantic, notably participating in the hunt of german pocket battleship Admiral Graf Spee and the Norwegian campaign.

After Phillipe Pétain signed the Armistice of 22 June 1940, the fleet retreated to the gulf of mexico waiting to know whether or not Louisiana would keep on fighting. After a 4 months controversy Louisiana remained at war with Germany and Italy.

The planned aircraft shift to Dewoitine D.790 fighters and Latécoère 299 bombers was no longer an option so american planes had to be chosen once again. 60 G-36A (french export variant of Grumman F4F) and an equal number of Dauntless SBD-3 were taken from the former french order. The latter had to be modified in the same way as the vindicator to undertake torpedo launching task. The former aircrafts were not stricken from the list of naval aircraft and were redeployed to newly converted auxiliary aircraft carriers to undertake anti-submarine warfare, notoriously in the Battle of the Caribbean.
The three "Croiseur d’aviation" were involved in Operation Springbok (invasion of Suid-Afrikaanse Republiek) but refused to cooperate in Operation Ironclad and Operation Stream Line Jane (Battle of Madagascar). They then moved to european waters from Operation Torch to Operation Dragoon, proudly supporting the liberation of french territories. They then mooved to the pacific till the end of hostilities.


A word about the sources and design:
The base concept was that of US flight deck cruiser, which i wanted to adapt since a long time. I hesitated between a South-African ship and a Louisianan one. Choosing the latter i had to reflect the french influence. I departed from the excellent Charguizard de Villers-class (from Treaty Cruiser Design Challenge) reverted with its turrets firing aft. the aviation facilitie was sourced from TigerHunter1945 Georges Cuvier-Class (from Second World War Aircraft Carrier Challenge). AIrcrafts were picked from Charybdis 1940 CV-7 Wasp drawing.

The planes will be posted in FD section.

[Perky50]

[][/img]
HMS Reprisal
As built
34,750 tons
8 x 15”
16 x 4”
4 x quad 2 pdr
4 x quad .5 HMG
2 saluting guns

27.5 knots

While on fleet maneuvers in September of 1929, HMS Royal Sovereign was rammed amidships by HMS Ramilles, causing severe flooding amidships and significant structural damage. After an epic salvage operation, HMS Royal Sovereign would reach port four days later. After removing all munitions and fuel, Royal Sovereign would be taken in hand at Palmers, Jarrow to assess damages and hopefully effect repairs.
Work on the crippled battleship had hardly begun, a fire broke out deep in the bowels of the ship. There followed a series of explosions which impeded attempts to tackle the blaze, which allowed the fires to spread further. By the time the fires were extinguished, HMS Royal Sovereign would be severely damaged and classified as a constructive loss.
In the great scandals that followed which pointed to communist intrigues and ties to the Labour party, Ramsay MacDonald’s newly elected government would collapse, and in the election the followed, Stanley Baldwin’s Conservatives would be swept into power with a historic landslide.
As a focal point of the saga, the wreck of Royal Sovereign would not be forgotten. The survey of the wreckage would show that while the central structure and engineering spaces of the derelict battleship were indeed a total loss, the main armament and certain other elements of the ship were indeed salvageable.
A plan was formulated whereby the main armament, certain elements of the armour plating and other elements would be salvaged to be incorporated into a new battleship to replace the lost vessel. While there were reservations in some circles regarding just how such an option might impact the various signatories of the Washington naval treaty, a surprising majority of the British populace was demanding a replacement of ‘their’ battleship.

While the armament had been decided upon by default due to the loss of Royal Sovereign, just how the rest of the new ship would be configured remained to be decided. There were several factors that would play into the process, and each would have to be sorted through before the final decision on design could be made.
The government had made it very clear that the new ship must be within the limitations of the Washington Treaty, however in stating that they would also demand a strong and versatile ship be completed for the fleet.
The initial designs would be a close development of design 16A, a well protected outwardly traditional design with a design speed of 23 knots. However, neither the armament or armour salvaged from Royal Sovereign would be of great use in this design. As a result, the design research would shift into other options.
As the process shifted away from the traditional battleship focus, a new focus would become apparent, that of a fast battleship, and this would be promptly focused on. Design elements would come from several sources, with the basic hull design being centered on the 16A design, refined by the latest data from the testing center at Haslar.
For power, the propulsion system would be based on advanced plans for the next generation of battleships which were projected to begin construction in the mid to late 1930’s.
As to protection, the new ship would follow the Royal Navy’s version of the ‘all or nothing’ format first brought forth in the Nelson class, backed up by the ‘liquid-dry-liquid’ system of bulkheads that first appeared in those earlier ships. While the new ship would have deck armour reflective of the 16A design, the belt armour would be an exterior belt of 13” thickness. As much as possible would be from that salvaged from Royal Sovereign, with new production being used to cover for shortfalls.
Originally, it was felt that a secondary battery of 6-inch guns mounted in twin turrets was needed. However, due to a combination of lack of space due to the larger demands for more engineering spaces -as well as weight constraints – this proposed armament could not be fitted. This would leave the only option available being a dual-purpose battery.
It had been hoped to use the 4.7” in a new between decks twin mount that had been originally proposed for the 16A type. However, here again the reality of the day would prevent these mounts from being ready in time. This would leave the tried and true 4-inch mount to fill the void initially, until a better option might appear in the future. While initially, this battery would have been 4 single mounts on either side, by the time the ship was ready to receive them, twin mounts were available resulting in the doubling of the battery.
HMS Reprisal would be commissioned into the Royal Navy in August of 1934 and would begin her service with the fleet with little fanfare. Reprisal would prove to be a practical addition to the RN, and while other ships would capture more of the glory, Reprisal would deliver Yeoman service to the RN, particularly in the early years of the war.
While Reprisal would take part in several battles, both large and small, her major claim to fame was that she would forever be know as ‘The Savior of Palmers’. For even as she left that great shipyard, her berth was taken by HMS Hood, who would be taken in hand for a three-year reconstruction. Other old veterans would follow, both the tired -and once the war started -the crippled.
Reprisal would see service in the Atlantic, Mediterranean and Pacific, taking part in several battles. She was one of only a few allied warships which managed to sink warships of all three of the Axis fleets, with her final victory being the spectacular destruction of the Japanese battleship Fuso while screening the Saigon landings in 1944.
It was only moments after that HMS Reprisal was taken under fire by the Japanese battleship Musashi. In the next twenty minutes, Reprisal was struck by 5-18 shells which caused catastrophic damage. Reprisal would struggle free and limp back to Singapore. While the ship’s condition would be stabilized, her damages were too profound to be worth repairing, and she would see no further service during the war. She would be sold for scrap in September of 1945.

[Rodondo]

Design 16D (as drafted 1930)



The impending retirement of the Iron Duke Class in the late 1920's/early 30's lead to the options being explored by the DNC as to possible replacements. The ROyal Navy was considering a 33kt battleship of 3 units to replace the 4 units of Iron Duke, however numerical superiosty and global availibility was requested as an alternative design constraint as a 1:1 replacement. This resulted in a tight design named the 16D, managing to carry the 16" guns and capable of hounding down any equivalent ship, the Deutschland being strongly hinted at in this 1930 draft, capable of reaching 28.2 knots clean and at third load, 26 at deep. The constraints though had serious implications, the AA suite and secondary armament was essentially the same as a Leander calss cruiser and was expected to be bolstered in wartime. The range of 5700nm was also deemed to be a little low however the armour was expected to surpass any ship of the smae size and neared the Nelson's in terms of protcetion, being just a inch thinner on the belt and having slightly less TDS depth. Whilst considered for 3 months, they were dropped in the economic climate and considerations into treaty changes.

Displacement:
23,865 t light; 24,995 t standard; 25,793 t normal; 26,432 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(686.97 ft / 680.00 ft) x 80.50 ft x (28.00 / 28.55 ft)
(209.39 m / 207.26 m) x 24.54 m x (8.53 / 8.70 m)

Armament:
6 - 16.00" / 406 mm 45.0 cal guns - 2,065.46lbs / 936.88kg shells, 75 per gun
Breech loading guns in turret on barbette mounts, 1932 Model
2 x Twin mounts on centreline, forward deck forward
1 raised mount - superfiring
1 x Twin mount on centreline, aft deck aft
8 - 6.00" / 152 mm 45.0 cal guns - 108.92lbs / 49.41kg shells, 125 per gun
Breech loading guns in turret on barbette mounts, 1932 Model
6 x Twin mounts on sides, evenly spread
4 - 4.00" / 102 mm 45.0 cal guns - 32.27lbs / 14.64kg shells, 220 per gun
Breech loading guns in deck mounts, 1932 Model
6 x Single mounts on sides, evenly spread
6 raised mounts
24 - 1.60" / 40.6 mm 45.0 cal guns - 2.07lbs / 0.94kg shells, 800 per gun
Anti-air guns in deck mounts, 1932 Model
3 x 2 row octuple mounts on sides, aft deck forward
3 raised mounts
Weight of broadside 13,443 lbs / 6,098 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 13.0" / 330 mm 390.00 ft / 118.87 m 18.00 ft / 5.49 m
Ends: 6.00" / 152 mm 75.00 ft / 22.86 m 18.00 ft / 5.49 m
215.00 ft / 65.53 m Unarmoured ends
Main Belt covers 88 % of normal length
Main Belt inclined 15.00 degrees (positive = in)

- Torpedo Bulkhead - Strengthened structural bulkheads:
2.00" / 51 mm 415.00 ft / 126.49 m 38.00 ft / 11.58 m
Beam between torpedo bulkheads 67.50 ft / 20.57 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 14.0" / 356 mm 8.00" / 203 mm 12.0" / 305 mm
2nd: 1.50" / 38 mm 1.50" / 38 mm 4.00" / 102 mm

- Protected deck - single deck:
For and Aft decks: 5.00" / 127 mm

- Conning towers: Forward 10.00" / 254 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 64,500 shp / 48,117 Kw = 28.20 kts
Range 5,700nm at 11.36 kts
Bunker at max displacement = 1,437 tons

Complement:
1,016 - 1,322

Cost:
£10.675 million / $42.700 million

Distribution of weights at normal displacement:
Armament: 2,241 tons, 8.7 %
- Guns: 2,241 tons, 8.7 %
Armour: 10,988 tons, 42.6 %
- Belts: 4,236 tons, 16.4 %
- Torpedo bulkhead: 1,167 tons, 4.5 %
- Armament: 2,316 tons, 9.0 %
- Armour Deck: 3,081 tons, 11.9 %
- Conning Tower: 188 tons, 0.7 %
Machinery: 1,904 tons, 7.4 %
Hull, fittings & equipment: 8,733 tons, 33.9 %
Fuel, ammunition & stores: 1,929 tons, 7.5 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
35,122 lbs / 15,931 Kg = 17.1 x 16.0 " / 406 mm shells or 5.9 torpedoes
Stability (Unstable if below 1.00): 1.00
Metacentric height 3.6 ft / 1.1 m
Roll period: 17.7 seconds
Steadiness - As gun platform (Average = 50 %): 59 %
- Recoil effect (Restricted arc if above 1.00): 1.25
Seaboat quality (Average = 1.00): 1.23

Hull form characteristics:
Hull has a flush deck,
a normal bow and small transom stern
Block coefficient (normal/deep): 0.589 / 0.592
Length to Beam Ratio: 8.45 : 1
'Natural speed' for length: 28.04 kts
Power going to wave formation at top speed: 47 %
Trim (Max stability = 0, Max steadiness = 100): 48
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: -3.00 ft / -0.91 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 26.00 ft / 7.92 m, 21.00 ft / 6.40 m
- Forward deck: 30.00 %, 21.00 ft / 6.40 m, 18.00 ft / 5.49 m
- Aft deck: 35.00 %, 18.00 ft / 5.49 m, 18.00 ft / 5.49 m
- Quarter deck: 15.00 %, 18.00 ft / 5.49 m, 19.00 ft / 5.79 m
- Average freeboard: 19.53 ft / 5.95 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 80.4 %
- Above water (accommodation/working, high = better): 142.4 %
Waterplane Area: 40,624 Square feet or 3,774 Square metres
Displacement factor (Displacement / loading): 97 %
Structure weight / hull surface area: 181 lbs/sq ft or 884 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.96
- Longitudinal: 1.37
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Excellent accommodation and workspace room
Good seaboat, rides out heavy weather easily

[waritem]

Very nice, It looks like an upscaled version of the Charguizard de Villers-class concept (from Treaty Cruiser Design Challenge).
By the way drawing your float-planes in FD scale would be a nice addition.............

Thaaanks, and yes, I did get some inspiration though, the ship's design is based on the “North Carolina Preliminary Scheme F 1934-35”, such a beautiful ship.
And of course, at some point I will make the planes in FD scale.

I'm i wrong or one this floatplanes is inspired by the Levasseur P-l201?
I was quite sure someone already draw it in FD scale, but i can't manage to find it back........