WesWorld

Quoted

Originally posted by Rooijen10
I would think it is less complicated than the octuple 40mm mounts I used before on various ships.

I would agree with that sentiment.

Ittan Momen, Japan Youkai laid down 1943


Displacement:
0 t light; 0 t standard; 0 t normal; 0 t full load

Dimensions: Length overall / water x beam x draught
34.78 ft / 34.78 ft x 0.98 ft x 0.17 ft (normal load)
10.60 m / 10.60 m x 0.30 m x 0.05 m

Armament:
Body Attack

Machinery:
Diesel Internal combustion motors,
Direct drive, 1 shaft, 0 shp / 0 Kw = 0.00 kts
Range 0nm at 0.00 kts
Bunker at max displacement = 0 tons

Complement:
0 - 0

Cost:
£0.000 million / $0.000 million

Distribution of weights at normal displacement:
Armament: 0 tons, 0.0%
Machinery: 0 tons, 0.0%
Hull, fittings & equipment: 0 tons, 97.5%
Fuel, ammunition & stores: 0 tons, 2.5%
Miscellaneous weights: 0 tons, 0.0%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
15 lbs / 7 Kg = 505,225,800,000.0 x 0.0 " / 0 mm shells or 5.3 torpedoes
Stability (Unstable if below 1.00): 1.04
Metacentric height 0.0 ft / 0.0 m
Roll period: 5.7 seconds
Steadiness - As gun platform (Average = 50 %): 0 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 0.00

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.850
Length to Beam Ratio: 35.33 : 1
'Natural speed' for length: 5.90 kts
Power going to wave formation at top speed: 0 %
Trim (Max stability = 0, Max steadiness = 100): 0
Bow angle (Positive = bow angles forward): 0.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 0.56 ft / 0.17 m
- Forecastle (20%): 0.56 ft / 0.17 m
- Mid (50%): 0.56 ft / 0.17 m
- Quarterdeck (15%): 0.56 ft / 0.17 m
- Stern: 0.56 ft / 0.17 m
- Average freeboard: 0.56 ft / 0.17 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 2.1%
- Above water (accommodation/working, high = better): +
Waterplane Area: 32 Square feet or 3 Square metres
Displacement factor (Displacement / loading): 1,000%
Structure weight / hull surface area: 2 lbs/sq ft or 11 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.61
- Longitudinal: 0.86
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has quick, lively roll, not a steady gun platform
Caution: Lacks seaworthiness - very limited seakeeping ability

And the actual design...

... maybe I should make it a regular carrier...

Ittanmomen, Japan Amphibious Assault Carrier laid down 1943

Displacement:
18,000 t light; 18,816 t standard; 22,283 t normal; 25,057 t full load

Dimensions: Length overall / water x beam x draught
729.05 ft / 700.00 ft x 75.00 ft x 25.61 ft (normal load)
222.22 m / 213.36 m x 22.86 m x 7.81 m

Armament:
16 - 2.95" / 75.0 mm guns (8x2 guns), 12.00lbs / 5.44kg shells, 1943 Model
Automatic rapid fire guns in deck mounts with hoists
on side ends, evenly spread
24 - 1.57" / 40.0 mm guns (4x6 guns), 2.00lbs / 0.91kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side, all amidships, 2 raised mounts - superfiring (starboard side)
36 - 1.57" / 40.0 mm guns (6x6 guns), 2.00lbs / 0.91kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side ends, majority aft
6 - 1.57" / 40.0 mm guns (1x6 guns), 2.00lbs / 0.91kg shells, 1943 Model
Anti-aircraft guns in deck mount
on centreline forward
32 - 0.98" / 25.0 mm guns (8x4 guns), 0.57lbs / 0.26kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 342 lbs / 155 kg
Shells per gun, main battery: 1,500

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.00" / 51 mm 480.00 ft / 146.30 m 10.50 ft / 3.20 m
Ends: Unarmoured
Main Belt covers 105% of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm - 1.00" / 25 mm
2nd: 1.00" / 25 mm - -
3rd: 1.00" / 25 mm - -
4th: 1.00" / 25 mm - -
5th: 1.00" / 25 mm - -

- Armour deck: 1.00" / 25 mm, Conning tower: 3.00" / 76 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 92,164 shp / 68,754 Kw = 30.00 kts
Range 20,000nm at 15.00 kts
Bunker at max displacement = 6,240 tons

Complement:
911 - 1,185

Cost:
£6.574 million / $26.295 million

Distribution of weights at normal displacement:
Armament: 49 tons, 0.2%
Armour: 1,231 tons, 5.5%
- Belts: 420 tons, 1.9%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 34 tons, 0.2%
- Armour Deck: 726 tons, 3.3%
- Conning Tower: 51 tons, 0.2%
Machinery: 2,380 tons, 10.7%
Hull, fittings & equipment: 6,190 tons, 27.8%
Fuel, ammunition & stores: 4,283 tons, 19.2%
Miscellaneous weights: 8,150 tons, 36.6%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
31,979 lbs / 14,505 Kg = 2,484.4 x 3.0 " / 75 mm shells or 2.8 torpedoes
Stability (Unstable if below 1.00): 1.05
Metacentric height 3.5 ft / 1.1 m
Roll period: 16.7 seconds
Steadiness - As gun platform (Average = 50 %): 51 %
- Recoil effect (Restricted arc if above 1.00): 0.03
Seaboat quality (Average = 1.00): 1.29

Hull form characteristics:
Hull has low quarterdeck
and transom stern
Block coefficient: 0.580
Length to Beam Ratio: 9.33 : 1
'Natural speed' for length: 30.09 kts
Power going to wave formation at top speed: 52 %
Trim (Max stability = 0, Max steadiness = 100): 40
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 10.00 ft / 3.05 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 33.00 ft / 10.06 m
- Forecastle (15%): 24.00 ft / 7.32 m
- Mid (50%): 24.00 ft / 7.32 m
- Quarterdeck (35%): 16.00 ft / 4.88 m (24.00 ft / 7.32 m before break)
- Stern: 16.00 ft / 4.88 m
- Average freeboard: 21.74 ft / 6.63 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 78.4%
- Above water (accommodation/working, high = better): 197.0%
Waterplane Area: 39,260 Square feet or 3,647 Square metres
Displacement factor (Displacement / loading): 153%
Structure weight / hull surface area: 106 lbs/sq ft or 518 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.99
- Longitudinal: 1.08
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Good seaboat, rides out heavy weather easily


Well deck: 210x56x9ft (64.01x17.07x2.74m)= 2994 tons simmed as bunker. Actual range is 10,000nm at 15 knots.

- 1600 tons for 40 planes.
- 200 tons for 8 spare planes.
- 40 tons for catapults.
- 100 tons for flagship facilities.
- 50 tons for heavy duty elevator forward.
- 15 tons for elevator aft of island.
- 300 tons for Flight Deck reinforcements aft.
- 128 tons for aircraft repair shop.
- 100 tons for vehicle/small boat repair shop + crane.
- 160 tons for aircraft spare parts.
- 150 tons for vehicle, tank, and landing craft spares.
- 1200 tons for 600 Troops.
- 800 tons for 4x Heavy Landing Craft.
- 45 tons for 12x Shohatsu landing craft.
- 100 tons for Shohatsu launch deck + cranes (on quarterdeck).
- 800 tons for 20 tanks @40 tons.
- 500 tons for 50 vehicles @10 tons.
- 61 tons for two sets of high-capacity pumps (to flood or drain well deck).
- 80 tons for flight operations center.
- 80 tons for briefing room.
- 100 tons for carrier command center.
- 150 tons for radar, sonar and electronics.
- 180 tons for damage control and fire suppression systems.
- 45 tons for emergency diesel generators.
- 180 tons for air condition system.
- 146 tons for degaussing coils.
- 612 tons for combat-loaded supplies.
- 24 tons for 75mm loading, training and elevation systems.
- 22 tons for 40mm loading, training and elevation systems.
- 2 tons for 25mm loading, training and elevation systems.
- 180 tons for crew comfort.
Total: 8150 tons

Quoted

Originally posted by Rooijen10
And the actual design...

... maybe I should make it a regular carrier...

I got yelled at when I tried designing Tenacious as an amphibious carrier.

I don't think the freeboard is anywher near high enough to accommodate an airgroup, a well deck, vehicles, and 1,200 troops.

The concept overall doesn't make sense until troop-carrying helicopters and the doctrine behind them exist. The aicraft carrier and landing ship functions have very different operating requirements.

Quoted

I got yelled at when I tried designing Tenacious as an amphibious carrier.

Was unaware of that. Must have missed that...

... and looking at the thread, I don't really get that impression (at least it does not look as bad as you make it out to be, unless you got yelled at in PMs)...

Quoted

I don't think the freeboard is anywher near high enough to accommodate an airgroup, a well deck, vehicles, and 1,200 troops.

That is assuming that the main deck = flight deck. The stem is at 33 feet. On the stem is a 40mm mount, so I assume that the deck is probably at least 40 feet above the water with the hangar below it.

The well deck is a major thing inside the ship, but the thing that really affects the hangar size is the Shohatsu area aft. In a sense, the whole QD area would be unusable for hangar space (the QD area is also roughly the area of the well deck).

Normally, one of the limits of the number of planes on a ship is calculated as l*b/750. This would result in space for 70 planes. However, since 35% of the length is unusable, I applied 0.65*l*b/750 which gives 45.5.

And why do I have to stuff 1200 troops inside the ship? Don't have enough tons for that.

Quoted

The concept overall doesn't make sense until troop-carrying helicopters and the doctrine behind them exist. The aicraft carrier and landing ship functions have very different operating requirements.

It is a bit like what wiki says of the Akitsu Maru's planned role: provide aircover during amphibious and landing operations. Unlike the OTL IJA carriers, these have deck-landing capability so they're probably a bit more useful than those OTL ships.

Quoted

Originally posted by Rooijen10

Quoted

The concept overall doesn't make sense until troop-carrying helicopters and the doctrine behind them exist. The aicraft carrier and landing ship functions have very different operating requirements.

It is a bit like what wiki says of the Akitsu Maru's planned role: provide aircover during amphibious and landing operations. Unlike the OTL IJA carriers, these have deck-landing capability so they're probably a bit more useful than those OTL ships.

I must still express my incredulity - amphibious assault carriers are more a 1960s thing. What justification is there for it existing in the 1940s?

Quoted

Originally posted by Rooijen10

Quoted

I got yelled at when I tried designing Tenacious as an amphibious carrier.

Was unaware of that. Must have missed that...

... and looking at the thread, I don't really get that impression (at least it does not look as bad as you make it out to be, unless you got yelled at in PMs)...

Well, 'yelled at' in the sedate, collegial fashion that we tend to do around here. Like the above comments.

"Strongly discouraged", maybe. :B

Quoted

Originally posted by Brockpaine

Quoted

Originally posted by Rooijen10

Quoted

The concept overall doesn't make sense until troop-carrying helicopters and the doctrine behind them exist. The aicraft carrier and landing ship functions have very different operating requirements.

It is a bit like what wiki says of the Akitsu Maru's planned role: provide aircover during amphibious and landing operations. Unlike the OTL IJA carriers, these have deck-landing capability so they're probably a bit more useful than those OTL ships.

I must still express my incredulity - amphibious assault carriers are more a 1960s thing. What justification is there for it existing in the 1940s?

I have to agree. While the Akitsu Maru and her sister were completed during the Second World War, and in service, they did not serve in any capacity akin to an amphibious assault carrier.

1 - They were equipped to carry only eight aircraft, and to launch, not recover them.

2 - They were not equipped with a hangar - while the flying off deck was carried high the aircraft were merely carried on the main deck; while they were reported to have operated autgyros, this appears to be disputed.

3 - They served principally as transports, and in no way acted in the role of an amphibious assault carrier.

Even if in the end they were not used for it, they were built for it.

Japan currently has 3 Kumano class ships operational and the idea of this class is to remove the limited ability to operate planes that the Kumano's have.

But like I said, maybe I should make it a regular carrier. The more I look at it, the more it makes me think of a helicopter-less LHD...


The 100% carrier version before I started altering it...

Ittanmomen, Japan Carrier laid down 1943

Displacement:
18,000 t light; 18,780 t standard; 20,480 t normal; 21,839 t full load

Dimensions: Length overall / water x beam x draught
723.78 ft / 700.00 ft x 74.00 ft x 25.00 ft (normal load)
220.61 m / 213.36 m x 22.56 m x 7.62 m

Armament:
16 - 2.95" / 75.0 mm guns (8x2 guns), 12.00lbs / 5.44kg shells, 1943 Model
Automatic rapid fire guns in deck mounts with hoists
on side ends, evenly spread
24 - 1.57" / 40.0 mm guns (4x6 guns), 2.00lbs / 0.91kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side, all amidships, 2 raised mounts - superfiring
36 - 1.57" / 40.0 mm guns (6x6 guns), 2.00lbs / 0.91kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side ends, evenly spread
6 - 1.57" / 40.0 mm guns (1x6 guns), 2.00lbs / 0.91kg shells, 1943 Model
Anti-aircraft guns in deck mount
on centreline forward
32 - 0.98" / 25.0 mm guns (8x4 guns), 0.57lbs / 0.26kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 342 lbs / 155 kg
Shells per gun, main battery: 1,500

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.00" / 51 mm 510.00 ft / 155.45 m 10.32 ft / 3.15 m
Ends: Unarmoured
Main Belt covers 112% of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm - 1.00" / 25 mm
2nd: 1.00" / 25 mm - -
3rd: 1.00" / 25 mm - -
4th: 1.00" / 25 mm - -
5th: 1.00" / 25 mm - -

- Armour deck: 1.00" / 25 mm, Conning tower: 3.00" / 76 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 196,948 shp / 146,923 Kw = 37.00 kts
Range 10,000nm at 15.00 kts
Bunker at max displacement = 3,060 tons

Complement:
855 - 1,112

Cost:
£9.054 million / $36.214 million

Distribution of weights at normal displacement:
Armament: 49 tons, 0.2%
Armour: 1,215 tons, 5.9%
- Belts: 434 tons, 2.1%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 34 tons, 0.2%
- Armour Deck: 699 tons, 3.4%
- Conning Tower: 48 tons, 0.2%
Machinery: 5,086 tons, 24.8%
Hull, fittings & equipment: 6,450 tons, 31.5%
Fuel, ammunition & stores: 2,480 tons, 12.1%
Miscellaneous weights: 5,200 tons, 25.4%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
19,387 lbs / 8,794 Kg = 1,506.1 x 3.0 " / 75 mm shells or 1.8 torpedoes
Stability (Unstable if below 1.00): 1.06
Metacentric height 3.5 ft / 1.1 m
Roll period: 16.5 seconds
Steadiness - As gun platform (Average = 50 %): 51 %
- Recoil effect (Restricted arc if above 1.00): 0.04
Seaboat quality (Average = 1.00): 1.01

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.554
Length to Beam Ratio: 9.46 : 1
'Natural speed' for length: 30.14 kts
Power going to wave formation at top speed: 62 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 3.00 ft / 0.91 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 36.00 ft / 10.97 m
- Forecastle (20%): 25.00 ft / 7.62 m
- Mid (50%): 25.00 ft / 7.62 m
- Quarterdeck (15%): 25.00 ft / 7.62 m
- Stern: 25.00 ft / 7.62 m
- Average freeboard: 25.88 ft / 7.89 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 112.0%
- Above water (accommodation/working, high = better): 210.3%
Waterplane Area: 37,763 Square feet or 3,508 Square metres
Displacement factor (Displacement / loading): 121%
Structure weight / hull surface area: 108 lbs/sq ft or 526 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.95
- Longitudinal: 1.48
- Overall: 1.00
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent


- 3025 tons for 55 planes.
- 250 tons for 10 spare planes.
- 400 tons additional aircraft ordnance
- 40 tons for catapults.
- 65 tons for elevators.
- 175 tons for aircraft repair shop.
- 220 tons for aircraft spare parts.
- 110 tons for flight operations center.
- 55 tons for briefing room.
- 100 tons for carrier command center.
- 162 tons for radar, sonar and electronics.
- 180 tons for damage control and fire suppression systems.
- 45 tons for emergency diesel generators.
- 180 tons for air condition system.
- 145 tons for degaussing coils.
- 24 tons for 75mm loading, training and elevation systems.
- 22 tons for 40mm loading, training and elevation systems.
- 2 tons for 25mm loading, training and elevation systems.
Total: 5200 tons

Regarding the lack of a hangar, that might have something to do with the fact that the Akitsu Maru and the Nigitsu Maru were originally laid down to be passenger ships and that a war was going on. Here in Wesworld, I deliberately dropped the "Maru" from "Kumano Maru" as indication that, eventhough it looks similar to the OTL vessel, it is different from the OTL vessel because it was purpose-built like the Shinshu Maru was OTL in the 1930s.

It does make me wonder now. If I had called it an "amphibious warfare ship" like I did with the Kumano, would it have given a different idea as to what this ship is?

Quoted

Originally posted by Rooijen10
It does make me wonder now. If I had called it an "amphibious warfare ship" like I did with the Kumano, would it have given a different idea as to what this ship is?

I think that people are willing to accept the Kumano design for what it is due to

Quoted

the limited ability to operate planes that the Kumano's have

At least I am.

The Ittanmomen design, as originally presented, was a full-fledged CVL and amphibious assault ship and amphibious command ship. I think that was taking the premise of the Akitsu Maru further than it could be sustained with the technology of present day WW. Indeed, my first reaction to it was "Sea Control Ship", which is a 1970s concept.

Just my two yen.

I think that one problem is that I don't want to build just another boring carrier. I wanted to do something different with it which is why I took the carrier and then crossed it with the Kumano and ended up with that.

Also, I rate it as a CV and not a CVL but that is just how I look at it. Amphibious command ship was not what I had in mind when designing it. I guess I should have left the flag facilities off when I kicked it off during the one of the many redesigning processes. *looks at USS Ancon and plans to clone it*

Not knowing about the "Sea Control Ship", I looked it up. Wiki says: "The SCS was intended as an escort vessel, providing air support for convoys."
With my limited knowledge, that sounds like something that is just the same as a WW2 escort carrier. I also don't see anything to indicate that the "Sea Control Ship" has anything to do with amphibious warfare.

Quoted

Just my two yen.

Should that not be "Sen"? Now it is like saying "Just my two Dollars".

Quoted

Originally posted by Rooijen10
Should that not be "Sen"? Now it is like saying "Just my two Dollars".

I am allowing for inflation.

Since I don't want just another carrier like I said before, I think I will go for a slightly updated Kumano design instead...


Kumano II, Japan amphibious warfare ship laid down 1943

Displacement:
7,938 t light; 8,143 t standard; 9,237 t normal; 10,113 t full load

Dimensions: Length overall / water x beam x draught
484.74 ft / 470.00 ft x 65.00 ft x 19.00 ft (normal load)
147.75 m / 143.26 m x 19.81 m x 5.79 m

Armament:
8 - 2.95" / 75.0 mm guns in single mounts, 12.00lbs / 5.44kg shells, 1943 Model
Dual purpose guns in deck mounts with hoists
on side, evenly spread
6 - 0.98" / 25.0 mm guns in single mounts, 0.57lbs / 0.26kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side, all aft
Weight of broadside 99 lbs / 45 kg
Shells per gun, main battery: 350

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 12,168 shp / 9,078 Kw = 19.00 kts
Range 10,000nm at 15.00 kts
Bunker at max displacement = 1,971 tons

Complement:
470 - 612

Cost:
£2.179 million / $8.717 million

Distribution of weights at normal displacement:
Armament: 13 tons, 0.1%
Machinery: 314 tons, 3.4%
Hull, fittings & equipment: 2,610 tons, 28.3%
Fuel, ammunition & stores: 1,300 tons, 14.1%
Miscellaneous weights: 5,000 tons, 54.1%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
15,254 lbs / 6,919 Kg = 1,185.0 x 3.0 " / 75 mm shells or 2.3 torpedoes
Stability (Unstable if below 1.00): 1.06
Metacentric height 2.9 ft / 0.9 m
Roll period: 16.0 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.02
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.557
Length to Beam Ratio: 7.23 : 1
'Natural speed' for length: 21.68 kts
Power going to wave formation at top speed: 40 %
Trim (Max stability = 0, Max steadiness = 100): 25
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 6.00 ft / 1.83 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 24.00 ft / 7.32 m
- Forecastle (20%): 19.80 ft / 6.04 m
- Mid (60%): 19.80 ft / 6.04 m
- Quarterdeck (10%): 19.80 ft / 6.04 m
- Stern: 19.80 ft / 6.04 m
- Average freeboard: 20.14 ft / 6.14 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 71.8%
- Above water (accommodation/working, high = better): 172.2%
Waterplane Area: 21,461 Square feet or 1,994 Square metres
Displacement factor (Displacement / loading): 161%
Structure weight / hull surface area: 81 lbs/sq ft or 393 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.94
- Longitudinal: 1.66
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Looks reasonable at first glance, but what's all behind that 5,000 tons of miscellaneous weight? Inquiring minds want to know.

Well, I need to look at the original design for that. The only thing I changed on the design is a bit more range so it should be the same as that one...

*digs through digital paperwork*

From here

Quoted

350 tons ------ 25 landing crafts
200 tons ------ Doors and landing craft launch system, cranes
2420 tons ----- 1210 soldiers
469 tons ------ Cargo
1369 tons ----- 37 planes
192 tons ------ 12 Type 90 tanks
5000 tons total

... maybe with the freed up tonnage I should build that big @$$ carrier support ship I planned for the Hiyo and Junyo...

Oshima, Japan Battleship laid down 1944

Displacement:
94,000 t light; 101,145 t standard; 108,162 t normal; 113,776 t full load

Dimensions: Length overall / water x beam x draught
1,043.71 ft / 1,020.00 ft x 130.00 ft (Bulges 140.00 ft) x 40.00 ft (normal load)
318.12 m / 310.90 m x 39.62 m (Bulges 42.67 m) x 12.19 m

Armament:
12 - 18.11" / 460 mm guns (4x3 guns), 3,913.21lbs / 1,775.00kg shells, 1944 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread, 2 raised mounts - superfiring
40 - 5.00" / 127 mm guns (20x2 guns), 55.12lbs / 25.00kg shells, 1944 Model
Automatic rapid fire guns in deck mounts with hoists
on side, all amidships, all raised mounts - superfiring
40 - 2.95" / 75.0 mm guns (20x2 guns), 12.00lbs / 5.44kg shells, 1944 Model
Automatic rapid fire guns in deck mounts with hoists
on side, evenly spread, 12 raised mounts
72 - 1.57" / 40.0 mm guns (12x6 guns), 2.00lbs / 0.91kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
160 - 0.98" / 25.0 mm guns (40x4 guns), 0.57lbs / 0.26kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 12 raised mounts
Weight of broadside 49,879 lbs / 22,625 kg
Shells per gun, main battery: 177

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 17.9" / 454 mm 600.00 ft / 182.88 m 17.00 ft / 5.18 m
Ends: 14.0" / 356 mm 140.00 ft / 42.67 m 8.00 ft / 2.44 m
280.00 ft / 85.34 m Unarmoured ends
Upper: 2.25" / 57 mm 600.00 ft / 182.88 m 23.00 ft / 7.01 m
Main Belt covers 90% of normal length

- Torpedo Bulkhead and Bulges:
3.00" / 76 mm 600.00 ft / 182.88 m 50.00 ft / 15.24 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 26.0" / 660 mm 15.0" / 381 mm 20.0" / 508 mm
2nd: 3.00" / 76 mm 1.00" / 25 mm 2.00" / 51 mm
3rd: 1.00" / 25 mm 1.00" / 25 mm 1.00" / 25 mm
4th: 1.00" / 25 mm 1.00" / 25 mm -
5th: 1.00" / 25 mm 1.00" / 25 mm -

- Armour deck: 9.00" / 229 mm, Conning tower: 20.00" / 508 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 201,754 shp / 150,509 Kw = 29.00 kts
Range 10,000nm at 18.00 kts
Bunker at max displacement = 12,631 tons

Complement:
2,981 - 3,876

Cost:
£54.868 million / $219.471 million

Distribution of weights at normal displacement:
Armament: 4,934 tons, 4.6%
Armour: 41,083 tons, 38.0%
- Belts: 9,917 tons, 9.2%
- Torpedo bulkhead: 3,330 tons, 3.1%
- Armament: 9,001 tons, 8.3%
- Armour Deck: 17,857 tons, 16.5%
- Conning Tower: 978 tons, 0.9%
Machinery: 5,152 tons, 4.8%
Hull, fittings & equipment: 38,831 tons, 35.9%
Fuel, ammunition & stores: 14,163 tons, 13.1%
Miscellaneous weights: 4,000 tons, 3.7%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
166,115 lbs / 75,349 Kg = 55.9 x 18.1 " / 460 mm shells or 33.6 torpedoes
Stability (Unstable if below 1.00): 1.05
Metacentric height 8.1 ft / 2.5 m
Roll period: 20.7 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.79
Seaboat quality (Average = 1.00): 1.22

Hull form characteristics:
Hull has low quarterdeck
and transom stern
Block coefficient: 0.663
Length to Beam Ratio: 7.29 : 1
'Natural speed' for length: 36.75 kts
Power going to wave formation at top speed: 46 %
Trim (Max stability = 0, Max steadiness = 100): 58
Bow angle (Positive = bow angles forward): 35.00 degrees
Stern overhang: 2.00 ft / 0.61 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 31.00 ft / 9.45 m
- Forecastle (31%): 21.20 ft / 6.46 m
- Mid (43%): 26.10 ft / 7.96 m
- Quarterdeck (7%): 19.20 ft / 5.85 m (26.10 ft / 7.96 m before break)
- Stern: 19.20 ft / 5.85 m
- Average freeboard: 25.02 ft / 7.63 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 67.6%
- Above water (accommodation/working, high = better): 175.6%
Waterplane Area: 107,247 Square feet or 9,964 Square metres
Displacement factor (Displacement / loading): 114%
Structure weight / hull surface area: 270 lbs/sq ft or 1,318 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.00
- Longitudinal: 1.00
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

Actual shells per gun
46cm = 120 rounds per gun (3131 tons total)
5" = 500 rounds per gun (735 tons total)
75mm = 1500 rounds per gun (535 tons total)
40mm = 2000 rounds per gun ( 131 tons total)
25mm = 3000 rounds per gun (306 tons total)
Total magazine weight: 4969 tons = ~177 rounds

94000
- 80 tons for helicopter landing pad.
- 50 tons for 2 helicopters.
- 400 tons for Admiral Togo flagship facilities
--- African Blackwood Furniture with golden decorations.
--- Brazilian cherry floor in living room, dining room, bed room, entrance hall and stairs.
--- Brazilian walnut sliding doors.
--- Gold and diamond chandelier above dining table.
--- Golden lamps.
--- Marble floor and wall tiles in bathroom.
--- Granite countertops and floor in kitchen.
--- Golden faucets for sink and kingsize bath.
--- Gold framed wall mirror.
--- Persian carpets in living room, dining room, bed room.
--- Steinway grand piano.
- 440 tons for fire control and fire control center
- 250 tons for radar systems
- 940 tons for damage control and fire suppression systems
- 235 tons emergency diesel generators
- 940 tons for air condition system
- 209 tons for degaussing coils
- 50 tons for 8x28 12 cm AA Rocket launchers
- 256 tons for improved elevation and train controls and loading systems.
- 150 tons for crew comfort.
Total: 4000 tons


- 17" armor on 0.875" STS plate inclined 20 degrees. 2.25" STS outer hull shell (decapping plate (=upper belt)).
- Bulbous bow and improved fitting of the shaft brackets and the bilge keels for reduction in the hull resistance, resulting in higher speed and better fuel efficiency.
- 1.25-2" CNC and DS forecastle deck. 9" MNC armored deck over the vitals, 13.4" VH in front of A turret and behind Y turret (sloped), 15" perforated MNC plates over the boiler uptakes. 2-3.15" CNC floors of the ammunition magazines.
- Main rudder room protected by armored box with 16" sides and 8" MNC top. Auxiliary rudder room protected by armored box with 12" sides and 8" MNC top. (both simmed using ends belt)

The Oshima design appears to be a technical tour de force. However, as a warship, I think it is massively impractical and a sink for resources. But that's just me.

Launched in July 1953 or thereabouts, done with trials early in 1954. Quite an act of faith...

Decided to use Nurikabe and Ittanmomen as names for the two unnamed carriers I had in my SS carrier directory when I changed the assault carriers into amphibious attack ships.

Nurikabe, Japan Carrier laid down 1944

Displacement:
52,000 t light; 54,295 t standard; 59,042 t normal; 62,840 t full load

Dimensions: Length overall / water x beam x draught
937.09 ft / 910.00 ft x 112.00 ft x 35.00 ft (normal load)
285.63 m / 277.37 m x 34.14 m x 10.67 m

Armament:
8 - 5.00" / 127 mm guns (4x2 guns), 55.12lbs / 25.00kg shells, 1944 Model
Automatic rapid fire guns in deck mounts with hoists
on side, all amidships, 2 raised mounts - superfiring
16 - 2.95" / 75.0 mm guns (8x2 guns), 12.00lbs / 5.44kg shells, 1944 Model
Automatic rapid fire guns in deck mounts with hoists
on side ends, evenly spread
72 - 1.57" / 40.0 mm guns (12x6 guns), 2.00lbs / 0.91kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
48 - 0.98" / 25.0 mm guns (12x4 guns), 0.57lbs / 0.26kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
16 - 0.98" / 25.0 mm guns (4x4 guns), 0.57lbs / 0.26kg shells, 1944 Model
Anti-aircraft guns in deck mounts
on centreline ends, evenly spread
Weight of broadside 813 lbs / 369 kg
Shells per gun, main battery: 1,990

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 6.00" / 152 mm 600.00 ft / 182.88 m 14.00 ft / 4.27 m
Ends: Unarmoured
Main Belt covers 101% of normal length

- Torpedo Bulkhead:
3.00" / 76 mm 600.00 ft / 182.88 m 33.00 ft / 10.06 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.00" / 76 mm 1.00" / 25 mm 2.00" / 51 mm
2nd: 1.00" / 25 mm - 1.00" / 25 mm
3rd: 1.00" / 25 mm - -
4th: 1.00" / 25 mm - -
5th: 0.50" / 13 mm - -

- Armour deck: 4.00" / 102 mm, Conning tower: 2.75" / 70 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 156,514 shp / 116,759 Kw = 30.00 kts
Range 10,000nm at 18.00 kts
Bunker at max displacement = 8,546 tons

Complement:
1,893 - 2,461

Cost:
£16.727 million / $66.909 million

Distribution of weights at normal displacement:
Armament: 127 tons, 0.2%
Armour: 10,151 tons, 17.2%
- Belts: 2,142 tons, 3.6%
- Torpedo bulkhead: 2,198 tons, 3.7%
- Armament: 85 tons, 0.1%
- Armour Deck: 5,636 tons, 9.5%
- Conning Tower: 90 tons, 0.2%
Machinery: 3,997 tons, 6.8%
Hull, fittings & equipment: 15,225 tons, 25.8%
Fuel, ammunition & stores: 7,042 tons, 11.9%
Miscellaneous weights: 22,500 tons, 38.1%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
87,602 lbs / 39,735 Kg = 1,401.6 x 5.0 " / 127 mm shells or 14.0 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 6.8 ft / 2.1 m
Roll period: 18.0 seconds
Steadiness - As gun platform (Average = 50 %): 61 %
- Recoil effect (Restricted arc if above 1.00): 0.02
Seaboat quality (Average = 1.00): 1.56

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.579
Length to Beam Ratio: 8.13 : 1
'Natural speed' for length: 34.69 kts
Power going to wave formation at top speed: 47 %
Trim (Max stability = 0, Max steadiness = 100): 39
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 4.00 ft / 1.22 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 40.00 ft / 12.19 m
- Forecastle (15%): 25.60 ft / 7.80 m
- Mid (55%): 25.60 ft / 7.80 m
- Quarterdeck (15%): 25.60 ft / 7.80 m
- Stern: 25.60 ft / 7.80 m
- Average freeboard: 26.46 ft / 8.07 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 82.5%
- Above water (accommodation/working, high = better): 196.2%
Waterplane Area: 76,165 Square feet or 7,076 Square metres
Displacement factor (Displacement / loading): 142%
Structure weight / hull surface area: 144 lbs/sq ft or 701 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.00
- Longitudinal: 1.00
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, can fire her guns in the heaviest weather


Actual rounds per gun
5" => 500 rpg = 122 tons
75mm => 1500 rpg = 214 tons
40mm => 2000 rpg = 262 tons
25mm => 3000 rpg = 515 tons
Total magazine weight: 1113 tons = 1990 rounds

52000
- 16641tons for 129 planes (129 tons per aircraft)
- 750 tons for 30 spare planes in crates (25 tons per aircraft)
- 1000 tons additional aircraft ordnance
- 500 tons for spare parts (4 tons per operational aircraft)
- 405 tons for repair shop (3 tons per operational aircraft, 1 ton per spare aircraft)
- 60 tons for hydraulic catapults (20 tons per catapult)
- 140 tons for elevators
- 250 tons for flight operations center (2 tons per operational aircraft)
- 125 tons for briefing room (1 ton per operational aircraft)
- 250 tons for flagship facilities
- 100 tons for carrier command center
- 440 tons for fire control and fire control center
- 200 tons for radar systems
- 520 tons for damage control and fire suppression systems (1 ton per 100 tons light displacement)
- 130 tons emergency diesel generators (1 ton per 400 tons light displacement)
- 520 tons for air condition system (1 ton per 100 tons light displacement)
- 188 tons for degaussing coils (1 ton per 5 feet of length (oa))
- 50 tons for 8x28 12 cm AA Rocket launchers
- 231 tons for crew comfort.
Total: 22500