WesWorld

Nisshin Maru, Japan Research Vessel laid down 1944, converted in 1948

Displacement:
6,480 t light; 6,633 t standard; 7,661 t normal; 8,483 t full load

Dimensions: Length overall / water x beam x draught
392.23 ft / 380.00 ft x 70.00 ft x 16.80 ft (normal load)
119.55 m / 115.82 m x 21.34 m x 5.12 m

Machinery:
Diesel Internal combustion motors,
No drive to shaft, 2 shafts, 14,893 shp / 11,110 Kw = 20.00 kts
Range 10,000nm at 15.00 kts
Bunker at max displacement = 1,850 tons

Complement:
409 - 532

Cost:
£1.884 million / $7.536 million

Distribution of weights at normal displacement:
Armament: 0 tons, 0.0 %
Machinery: 380 tons, 5.0 %
Hull, fittings & equipment: 2,100 tons, 27.4 %
Fuel, ammunition & stores: 1,181 tons, 15.4 %
Miscellaneous weights: 4,000 tons, 52.2 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
12,380 lbs / 5,616 Kg = 114.6 x 6 " / 152 mm shells or 2.2 torpedoes
Stability (Unstable if below 1.00): 1.06
Metacentric height 3.3 ft / 1.0 m
Roll period: 16.2 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 1.62

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.600
Length to Beam Ratio: 5.43 : 1
'Natural speed' for length: 19.49 kts
Power going to wave formation at top speed: 53 %
Trim (Max stability = 0, Max steadiness = 100): 43
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 5.00 ft / 1.52 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 27.00 ft / 8.23 m
- Forecastle (20 %): 18.00 ft / 5.49 m
- Mid (50 %): 18.00 ft / 5.49 m
- Quarterdeck (15 %): 18.00 ft / 5.49 m
- Stern: 18.00 ft / 5.49 m
- Average freeboard: 18.72 ft / 5.71 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 73.5 %
- Above water (accommodation/working, high = better): 163.1 %
Waterplane Area: 19,455 Square feet or 1,807 Square metres
Displacement factor (Displacement / loading): 161 %
Structure weight / hull surface area: 78 lbs/sq ft or 380 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.93
- Longitudinal: 2.04
- 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
Excellent seaboat, comfortable, rides out heavy weather easily

Miscellaneous weights breakdown (4000 tons)
Not sorted out yet.

I-350

Date: 1948
Type: Coastal
Length: 40.0m
Beam: 4.5m
Draft: 4.5m
Crush depth: 225.0m
Light Displacement 335t
Loaded Displacement 363t
Full Displacement 405t
wt fuel&batts: 60t
Reserve buoyancy: 10%

Armament:
- 2 x 21" (bow)
ElecHP: 1650hp
DieselHP: 225hp
Speed:
- Max Surf Speed: 8.2 knots
- Max Sub Speed: 16.2 knots
Range:
- Surfaced: 3,781nm@8 knots
- Submerged: 122nm@5 knots
Tons Oil: 20.0t
Tons Battery: 40.0t
Miscellaneous Weight: 50 tons

Crew: 18

- 6 Type 3 torpedoes (= 2 in the tubes + 4 from the 8 tons for 'mines or reload torpedoes').
- Diesel-electric drive.
- Main electric engine output: 1,550 shp.
- Silent running engine output: 100 shp.
- Surface speed: (diesel-electric) 16.1 knots.
- Submerged speed: (silent running engines) 6.3 knots, (battery-electric) 15.8 knots, (diesel-electric + Ninjatousaya) 10 knots.
- Range Surfaced (diesel): 3,781nm@8 knots.
- Range Submerged (batteries, silent running engine): 862nm@2 knots, 375nm@3 knots, 122nm@5 knots.
- Range Submerged (batteries, main engine): 35nm@8 knots, 17nm@10 knots, 3nm@15 knots.
- Endurance: (surfaced, diesel) 19 days and 16 hours @ 8 knots, (submerged, electric) 1 day @ 5 knots.
- Diving depth: 295 feet
- Emergency Depth: 472 feet
- Crush Depth: 738 feet
- 50 tons Miscellaneous weights breakdown:
--- 10 tons for Ninjatousaya System.
--- 20 tons for sonar and hydrophones.
--- 10 tons for air condition system.
--- 1 tons for 20 oxygen bottles (50 l, 150 atm).
--- 5 tons CO2 removal system + Soda lime.
--- 4 tons for desalinization gear.

The Anano is a test platform for the Funryu 4 (‘Raging Dragon’) Ship Launched Antiaircraft Rocket and is based on the Ashida class design. The superfiring main gun turrets were removed from the Ashida design and replaced by the Raiun ('Thundercloud') launch system. 75mm and 25mm guns, 61cm torpedoes and all ASWs were also removed while a few additional 40mm mounts were added. 1 inch protective plates cover part of the deck and the superstructure near and around the launchers.

Anano, Japan Experimental Light Cruiser laid down 1948

Displacement:
5,653 t light; 5,986 t standard; 6,951 t normal; 7,722 t full load

Dimensions: Length overall / water x beam x draught
559.17 ft / 540.00 ft x 49.50 ft x 19.00 ft (normal load)
170.43 m / 164.59 m x 15.09 m x 5.79 m

Armament:
4 - 5.00" / 127 mm guns (2x2 guns), 55.12lbs / 25.00kg shells, 1948 Model
Automatic rapid fire guns in deck mounts with hoists
on centreline ends, evenly spread
4 - 5.00" / 127 mm guns (2x2 guns), 0.00lbs / 0.00kg shells, 1948 Model
Automatic rapid fire guns in turrets (on barbettes)
on centreline ends, evenly spread, all raised mounts (see below)
48 - 1.57" / 40.0 mm guns (8x6 guns), 2.00lbs / 0.91kg shells, 1948 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 4 raised mounts
Weight of broadside 316 lbs / 144 kg
Shells per gun, main battery: 925 (see below)

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.00" / 51 mm 365.00 ft / 111.25 m 9.25 ft / 2.82 m
Ends: Unarmoured
Main Belt covers 104 % of normal length

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

- Armour deck: 0.75" / 19 mm, Conning tower: 6.00" / 152 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 59,785 shp / 44,600 Kw = 32.00 kts
Range 6,000nm at 20.00 kts
Bunker at max displacement = 1,736 tons

Complement:
379 - 494

Cost:
£3.543 million / $14.171 million

Distribution of weights at normal displacement:
Armament: 87 tons, 1.2 %
Armour: 661 tons, 9.5 %
- Belts: 277 tons, 4.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 84 tons, 1.2 %
- Armour Deck: 252 tons, 3.6 %
- Conning Tower: 47 tons, 0.7 %
Machinery: 1,461 tons, 21.0 %
Hull, fittings & equipment: 2,245 tons, 32.3 %
Fuel, ammunition & stores: 1,297 tons, 18.7 %
Miscellaneous weights: 1,200 tons, 17.3 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
7,672 lbs / 3,480 Kg = 122.8 x 5.0 " / 127 mm shells or 1.2 torpedoes
Stability (Unstable if below 1.00): 1.05
Metacentric height 1.9 ft / 0.6 m
Roll period: 15.0 seconds
Steadiness - As gun platform (Average = 50 %): 54 %
- Recoil effect (Restricted arc if above 1.00): 0.16
Seaboat quality (Average = 1.00): 1.09

Hull form characteristics:
Hull has low quarterdeck
and transom stern
Block coefficient: 0.479
Length to Beam Ratio: 10.91 : 1
'Natural speed' for length: 26.41 kts
Power going to wave formation at top speed: 56 %
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: 28.00 ft / 8.53 m
- Forecastle (20 %): 18.00 ft / 5.49 m
- Mid (50 %): 18.00 ft / 5.49 m
- Quarterdeck (20 %): 11.00 ft / 3.35 m (18.00 ft / 5.49 m before break)
- Stern: 11.00 ft / 3.35 m
- Average freeboard: 17.40 ft / 5.30 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 99.0 %
- Above water (accommodation/working, high = better): 164.3 %
Waterplane Area: 18,166 Square feet or 1,688 Square metres
Displacement factor (Displacement / loading): 127 %
Structure weight / hull surface area: 74 lbs/sq ft or 360 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.88
- Longitudinal: 1.25
- Overall: 0.91
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent

2x2 5" mounts (2nd gun) simmed for AA Rocket launcher mount.

Actual rounds per gun:
5" guns: 500 rounds per gun
40mm guns: 2500 rounds per gun

200 tons for 2x4 Raiun AA Rocket launch systems ('B' and 'X') and Funryu 4 rockets
50 tons for Air Search Radar
20 tons for Surface Search Radar
100 tons for Fire Control
57 tons for damage control and fire suppression systems
15 tons for emergency diesel generators
57 tons for air condition system
112 tons for degauss coiling
21 tons for 5" loading, training and elevation systems
16 tons for 40mm loading, training and elevation systems
160 tons for testing and experimental facilities
208 tons for 1 inch protective plating on deck and superstructure
184 tons for various


Funryu 4 (data and image from "Japanese Secret Projects")


Length: 4 meters
Diameter: 0.6 meters
Wingspan: 1.6 meters
Weight: 1900 kg
Engine: One Toko Ro.2 rocket engine, 1500 kg thrust
Warhead: 200 kg
Maximum Speed: 1099 km/h
Maximum Range: 30 kilometers
Ceiling: 15000 meters
Guidance: Beam Riding

Seems a reasonable design overall as a testbed.

I'm not sure whether its best to sim the launcher and missile magazine as a gun mount or just rely on misc weight.
I can see pros and cons with either method. At least this way it reserves space within the hull armour and some additional weight, although it will throw your recoil stats off a bit.

Quoted

I'm not sure whether its best to sim the launcher and missile magazine as a gun mount or just rely on misc weight.

It was done more for the 2" barbette that would appear in the sim report than the gun mount itself, though it could easily be done with just the miscellaneous weights (and the 100 ton per launcher + rockets is probably more than enough). I just like it more this way. :) (also looking at the sim the way it is, it should be obvious that the launchers are superfiring the main guns, although it probably is not necessary as, according to wiki, the rocket would have been launched at a 45° angle).

Quoted

although it will throw your recoil stats off a bit

A quick test showed that it is only 0.03 difference between this design and one without the superfiring mounts. Also it is well below 1 so I am not too worried about that.

In that case the rationale seems quite sound, and at least doing it that way will have given the correct topweight/ stability calc for the superfiring launchers.

I was thinking about the Ise and Hyuga today at work. Unlike the Fuso and Yamashiro, they have not been modernized with a partial reconstruction...

... not yet anyway. I thought that for fun I should go a bit OTL with them, remove the X and Y turrets and put a flight deck aft for rotary-wing aircraft.

Ise/Hyuga modification, Japan Senkan laid down 1914 (Engine 1949)


Displacement:
33,727 t light; 35,601 t standard; 39,435 t normal; 42,503 t full load

Dimensions: Length overall / water x beam x draught
717.96 ft / 710.00 ft x 97.00 ft (Bulges 108.00 ft) x 30.00 ft (normal load)
218.84 m / 216.41 m x 29.57 m (Bulges 32.92 m) x 9.14 m

Armament:
8 - 14.17" / 360 mm guns (4x2 guns), 1,400.00lbs / 635.03kg shells, 1946 Model
Breech loading guns in turrets (on barbettes)
on centreline, all forward, 2 raised mounts - superfiring
16 - 5.00" / 127 mm guns in single mounts, 55.12lbs / 25.00kg shells, 1946 Model
Quick firing guns in casemate mounts
on side, all forward
16 guns in hull casemates - Limited use in heavy seas
20 - 2.95" / 75.0 mm guns (10x2 guns), 12.00lbs / 5.44kg shells, 1946 Model
Automatic rapid fire guns in deck mounts with hoists
on side, evenly spread
36 - 1.57" / 40.0 mm guns (6x6 guns), 2.00lbs / 0.91kg shells, 1946 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
56 - 0.98" / 25.0 mm guns (14x4 guns), 0.57lbs / 0.26kg shells, 1946 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 12,426 lbs / 5,636 kg
Shells per gun, main battery: 153
168 - 4.7" / 120 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 14.0" / 356 mm 475.00 ft / 144.78 m 12.00 ft / 3.66 m
Ends: Unarmoured
Main Belt covers 103 % of normal length

- Torpedo Bulkhead and Bulges:
2.00" / 51 mm 475.00 ft / 144.78 m 29.00 ft / 8.84 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 16.0" / 406 mm 10.0" / 254 mm 14.0" / 356 mm
2nd: 4.00" / 102 mm - 4.00" / 102 mm
3rd: 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: 5.50" / 140 mm, Conning tower: 18.00" / 457 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 65,359 shp / 48,758 Kw = 24.00 kts
Range 10,000nm at 18.00 kts
Bunker at max displacement = 6,902 tons

Complement:
1,398 - 1,818

Cost:
£3.494 million / $13.975 million

Distribution of weights at normal displacement:
Armament: 1,599 tons, 4.1 %
Armour: 13,232 tons, 33.6 %
- Belts: 3,421 tons, 8.7 %
- Torpedo bulkhead: 1,019 tons, 2.6 %
- Armament: 3,217 tons, 8.2 %
- Armour Deck: 5,125 tons, 13.0 %
- Conning Tower: 449 tons, 1.1 %
Machinery: 1,580 tons, 4.0 %
Hull, fittings & equipment: 12,466 tons, 31.6 %
Fuel, ammunition & stores: 5,708 tons, 14.5 %
Miscellaneous weights: 4,850 tons, 12.3 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
57,685 lbs / 26,165 Kg = 40.5 x 14.2 " / 360 mm shells or 11.0 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 5.7 ft / 1.7 m
Roll period: 19.0 seconds
Steadiness - As gun platform (Average = 50 %): 61 %
- Recoil effect (Restricted arc if above 1.00): 0.34
Seaboat quality (Average = 1.00): 1.23

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.600
Length to Beam Ratio: 6.57 : 1
'Natural speed' for length: 26.65 kts
Power going to wave formation at top speed: 45 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.88 ft / 6.67 m
- Forecastle (20 %): 18.88 ft / 5.75 m
- Mid (73 %): 18.88 ft / 5.75 m (11.83 ft / 3.61 m aft of break)
- Quarterdeck (15 %): 11.83 ft / 3.61 m
- Stern: 11.83 ft / 3.61 m
- Average freeboard: 17.20 ft / 5.24 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 73.7 %
- Above water (accommodation/working, high = better): 110.2 %
Waterplane Area: 50,370 Square feet or 4,680 Square metres
Displacement factor (Displacement / loading): 116 %
Structure weight / hull surface area: 178 lbs/sq ft or 868 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.99
- Longitudinal: 1.03
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Good seaboat, rides out heavy weather easily



Actual 25mm mounts: 8x4 (= 32 guns)
6x4 25mm mounts simmed for AA Rocket launcher mount.
12cm Rockets simmed as Torpedoes.

Actual shells per gun (1085t)
36cm = 100 rounds per gun (622 tons total)
5" = 310 rounds per gun (152 tons total)
75mm = 1500 rounds per gun (200 tons total)
40mm = 2000 rounds per gun (80 tons total)
25mm = 3000 rounds per gun (31 tons total)


4850t
- 719 tons for X and Y barbettes.
- 500 tons for 20 rotary-wing aircraft.
- 250 tons for 5 spare aircraft in crates.
- 160 tons for spare parts (8 tons per operational aircraft).
- 130 tons for repair shop (6 tons per operational aircraft, 2 ton per spare aircraft).
- 100 tons for elevators.
- 1000 tons for reinforced hangar and flight deck structure.
- 80 tons for flight operations center (4 tons per operational aircraft).
- 40 tons for briefing room (2 ton per operational aircraft).
- 50 tons for carrier command center.
- 200 tons for fire control and fire control center
- 200 tons for radar systems
- 338 tons for damage control and fire suppression systems
- 85 tons emergency diesel generators
- 338 tons for air condition system
- 144 tons for degaussing coils
- 38 tons for 6x28 12 cm AA Rocket launchers
- 60 for mount improvements
--- 40 tons for 75mm mounts
--- 12 tons for 40mm mounts
--- 8 tons for 25mm mounts
- 418 tons for for crew comfort.

Partial Reconstruction: 16864 tons and 21.5 months required.

Go for it. :)

As one of the most guilty players for driving ships long past their practical lifetimes, I'd have to say it doesn't seem like a wise investment to modernize a pair of 1914 ships at this juncture.

Anything that prolongs the life of old tubs and reduces their fighting power even further gets a thumbs up from the Royal Navy!

I'm not sure what the rationale is for a helicopter carrier with 14in guns?
Its a fun concept but not sure what rationale it has in WW.

Hate to add to the negatives but I have to agree, its not really worth the refit and IMO actually reduces their combat effectiveness even as old as they are. You could spend as much on a small carrier or spend as much tonnage as one of these conversions on helicopter decks on various ships. The real reason the historical IJN did so many scout plane conversions was because they relied on them to find the enemy much in the way the Americans used radar so having large numbers on their fighting ships meant that they had closer co-ordination of scouting assets. The only problem was they converted many ships at a stage in the war where radar was a more efficient scouting device, one that the U.S. had a clear advantage with. In wesworld Japan isn't at the same disadvantage.

Rationally, the proposed refit would seem to make little sense for the reasons previously stated. But it does bring to mind a question.

The proposal calls for operating 20 rotary wing aircraft. Now, the refitted Hyuga would not be an aircraft carrier per se, but how would the air group rules apply in this instance? Do they apply?

Quoted

I'd have to say it doesn't seem like a wise investment to modernize a pair of 1914 ships at this juncture.

It is not but when did I ever do anything wise?

Still it is true. It is the same as the Fuso and Yamashiro which received a partial rebuild a few years ago. The tonnage is better spent on something else which in the end I will probably just do. If anything, the four ships should have had the partial reconstruction instead of the refit back then and the mid/late 1940s is just too late.

Quoted

Anything that prolongs the life of old tubs and reduces their fighting power even further gets a thumbs up from the Royal Navy!

*rolls out Alternative Plan B*

Quoted

I'm not sure what the rationale is for a helicopter carrier with 14in guns?
Its a fun concept but not sure what rationale it has in WW.

Not sure if there is any for a helicopter carrier at this point of time, whether it has 14" guns or not. I had been thinking with the coming of the jet age, the small carriers would become useless and probably should start using helicopters instead... but then, what was around back then that would be useful to be used on such small carriers? So I have not made that step either.

It is more an idea for fun and the ability to use that image and it will probably just remain an idea. OTL Ise and Hyuga were to carry D4Ys and E16As. As we are moving to the jet age, those two would be obsolete and I doubt the 70 meter flight deck would be useful for jets so that would mean rotary-wing aircraft instead... but at that point you get to the issue I mentioned above. What was useful back then?

Quoted

its not really worth the refit and IMO actually reduces their combat effectiveness even as old as they are.

Well, it is not really a refit. It is much more drastic than that. And reduced combat effectiveness is probably better than it vanishing completely by scrapping them.

Quoted

You could spend as much on a small carrier or spend as much tonnage as one of these conversions on helicopter decks on various ships.

The small carrier has the issues I mentioned above. Helicopter decks on various ships would probably be better once better helicopters come around.

Quoted

The proposal calls for operating 20 rotary wing aircraft. Now, the refitted Hyuga would not be an aircraft carrier per se, but how would the air group rules apply in this instance? Do they apply?

Not sure what air group rules you refer to but having thought about the springstyle notes, as helicopters probably should be considered "postwar", the value should most likely be 2/3 of what I gave just as one does with jets.

Quoted from "Rooijen10"

Not sure if there is any for a helicopter carrier at this point of time, whether it has 14" guns or not. I had been thinking with the coming of the jet age, the small carriers would become useless and probably should start using helicopters instead... but then, what was around back then that would be useful to be used on such small carriers? So I have not made that step either.

To be fair, the RCN has been extremely forward-thinking when it comes to shipborne helicopter applications, including the first practical operational use in that rescue op in Persia. So there is some rationale out there....you'd just have to admit to copying your Canadian betters, and paying a small fee.

Quoted from "Rooijen10"

OTL Ise and Hyuga were to carry D4Ys and E16As. As we are moving to the jet age, those two would be obsolete and I doubt the 70 meter flight deck would be useful for jets so that would mean rotary-wing aircraft instead... but at that point you get to the issue I mentioned above. What was useful back then?

It's worth remembering that Ise and Hyuga may have been intended to launch those aircraft, but there were no provisions for recovering them. More than any other of the IJN's wartime projects, this was very much a project fueled by desperation and expediency.

Quoted

you'd just have to admit to copying your Canadian betters, and paying a small fee

No thanks. Can't have my troops die from embarrassment while flying copies of those hideous Canadian flying contraptions.

Quoted

It's worth remembering that Ise and Hyuga may have been intended to launch those aircraft, but there were no provisions for recovering them. More than any other of the IJN's wartime projects, this was very much a project fueled by desperation and expediency.

I would think that it is quite easy to recover the E16A as wiki indicates that the Ise/Hyuga had a collapsible crane. As for the the D4Y, it is quite obvious that they were supposed to 'land' on enemy ships.

Super Battleship Harima I and Battleship Harima II...

Unfortunately (or maybe fortunately), the Imperial Japanese Navy destroyed all plans of both versions of the ship and hacked into my computer to remove all the SS data that there was on the original Harima design and the downgraded version.

Well, I could post them, but they are just silly designs and were never meant to be serious (-:

I-500

Date: 1949
Type: Oceanic
Length: 85.0m
Beam: 8.0m
Draft: 8.0m
Crush depth: 317.5m
Light Displacement 1946t
Loaded Displacement 2451t
Full Displacement 2720t
wt fuel&batts: 875t
Reserve buoyancy: 10%

Armament:
- 6 x 533mm (bow)
- 30 tons for mines or reload torpedoes
ElecHP: 10500hp
DieselHP: 1500hp
Speed:
- Max Surf Speed: 10.5 knots
- Max Sub Speed: 19.6 knots
Range:
- Surfaced: 18,184nm@10 knots
- Submerged: 373nm@5 knots
Tons Oil: 475.0t
Tons Battery: 400.0t
Miscellaneous Weight: 300 tons

Crew: 58

- 21 Type 3 torpedoes (= 6 in the tubes + 15 from the 30 tons for 'mines or reload torpedoes'), 3 idle positions to permit withdrawal of torpedoes from tubes for servicing (6 tons miscellaneous).
- Diesel-electric drive.
- Main electric engines output: 10,000 shp.
- Silent running engines output: 500 shp.
- Surface speed: (diesel-electric) 10.5 knots, (battery-electric) 20.1 knots.
- Submerged speed: (silent running engines) 7.1 knots, (battery-electric) 19.3 knots, (diesel-electric + Ninjatousaya) 10 knots.
- Range Surfaced (diesel-Electric): 22,449nm@9 knots, 18,184nm@10 knots.
- Range Submerged (batteries, silent running engines): 1,074nm@3 knots, 373nm@5 knots, 176nm@7 knots.
- Range Submerged (batteries, main engines): 70nm@10 knots, 19nm@15 knots, 7nm@19 knots.
- Range Submerged (diesel-electric + Ninjatousaya): 22,640nm@6 knots, 15,150nm@8 knots, 10,850@10 knots.
- Endurance: (surfaced, diesel) 75 days and 18 hours @ 10 knots, (submerged, batteries) 3 days and 2 hours @ 5 knots.
- Diving depth: 417 feet
- Emergency Depth: 667 feet
- Crush Depth: 1042 feet
- 300 tons Miscellaneous weights breakdown:
--- 23 tons for electric torpedo reloading system.
--- 15 tons for air-powered piston ejection pumps.
--- 5 tons for torpedo service material.
--- 6 tons for 3 idle torpedo positions in the torpedo rooms for torpedo servicing.
--- 10 tons for Ninjatousaya System.
--- 120 tons for sonar+, hydrophones, air search radar, air/surface radar and radar warning receiver.
--- 10 tons for defense countermeasures.
--- 20 tons for air condition system.
--- 10 tons for 200 oxygen bottles (50 l, 150 atm).
--- 10 tons for CO2 removal system + Soda lime.
--- 20 tons for damage control and fire suppression systems.
--- 15 tons for demagnetization cables.
--- 10 tons for safety and rescue equipment.
--- 10 tons for deep freeze unit.
--- 5 tons for desalinization gear.
--- 11 tons for crew comforts (toilets, showers, board games, puzzles, playing cards, dice games, etc.)

I-550

Date: 1949
Type: Coastal
Length: 60.0m
Beam: 6.0m
Draft: 6.0m
Crush depth: 225.0m
Light Displacement 844t
Loaded Displacement 968t
Full Displacement 1080t
wt fuel&batts: 280t
Reserve buoyancy: 10%

Armament:
- 4 x 533mm (bow)
- 24 tons for mines or reload torpedoes
ElecHP: 5000hp
DieselHP: 850hp
Speed:
- Max Surf Speed: 10.5 knots
- Max Sub Speed: 18.8 knots
Range:
- Surfaced: 6,806nm@10 knots
- Submerged: 307nm@5 knots
Tons Oil: 100.0t
Tons Battery: 180.0t
Miscellaneous Weight: 165 tons

Crew: 32

- 16 Type 3 torpedoes (= 4 in the tubes + 12 from the 24 tons for 'mines or reload torpedoes'), 2 idle positions to permit withdrawal of torpedoes from tubes for servicing (4 tons miscellaneous).
- Diesel-electric drive.
- Main electric engines output: 4,750 shp.
- Silent running engines output: 250 shp.
- Surface speed: (diesel-electric) 10.5 knots, (battery-electric) 19.2 knots.
- Submerged speed: (silent running engines) 6.9 knots, (battery-electric) 18.5 knots, (diesel-electric + Ninjatousaya) 10 knots.
- Range Surfaced (diesel-Electric): 8,402nm@9 knots, 6,806nm@10 knots.
- Range Submerged (batteries, silent running engines): 893nm@3 knots, 307nm@5 knots, 205nm@6 knots.
- Range Submerged (batteries, main engines): 55nm@10 knots, 14nm@15 knots, 7nm@18 knots.
- Range Submerged (diesel-electric + Ninjatousaya): 8,480nm@6 knots, 5,673nm@8 knots, 4,082@10 knots.
- Endurance: (surfaced, diesel) 28 days and 8 hours @ 10 knots, (submerged, batteries) 2 days and 13 hours @ 5 knots.
- Diving depth: 295 feet
- Emergency Depth: 472 feet
- Crush Depth: 738 feet
- 165 tons Miscellaneous weights breakdown:
--- 15 tons for electric torpedo reloading system.
--- 10 tons for air-powered piston ejection pumps.
--- 5 tons for torpedo service material.
--- 4 tons for 2 idle torpedo positions in the torpedo rooms for torpedo servicing.
--- 10 tons for Ninjatousaya System.
--- 50 tons for sonar, hydrophones, air search radar, air/surface radar and radar warning receiver.
--- 10 tons for air condition system.
--- 6 tons for 120 oxygen bottles (50 l, 150 atm).
--- 10 tons for CO2 removal system + Soda lime.
--- 10 tons for damage control and fire suppression systems.
--- 10 tons for demagnetization cables.
--- 5 tons for safety and rescue equipment.
--- 5 tons for deep freeze unit.
--- 5 tons for desalinization gear.
--- 10 tons for crew comforts (toilets, showers, board games, puzzles, playing cards, dice games, etc.)