WesWorld

Frigates of the Japanese Navy.

Data here is the data released to the public

Ao Ichi Class
A-1 to A-30

Dimensions: 370.00 ft x 35.00 ft x 12.00 ft
Standard Displacement: 1930 tons
Armament: 4 - 13.0 cm / 50 cal Model 1914 guns
6 - 50 mm / 60 cal Model 1914 AA guns
18 - 25 mm / 60 cal Model 1914 light AA guns
Armour: Belt 2.00"
Main gun shields 2.00", AA gun shields 1.00", Light AA gun shields 1.00"
Armour deck 1.00"
Machinery: 3 Kanpon oil fired boilers, Brown Curtis geared steam turbines,
Geared drive, 2 shafts, 11,000 shp = 23.00 kts
Range 5,500nm at 12.00 kts
Complement: 23 Officers, 196 other rank

Ao Ichi, Japan Frigate/Large sub hunter laid down 1914
All scrapped in 1942/43

Displacement:
1,863 t light; 1,932 t standard; 2,220 t normal; 2,441 t full load
Loading submergence 233 tons/feet

Dimensions:
370.00 ft x 35.00 ft x 12.00 ft (normal load)
112.78 m x 10.67 m x 3.66 m

Armament:
4 - 5.12" / 130 mm guns
6 - 1.97" / 50 mm AA guns
18 - 0.98" / 25 mm guns
Weight of broadside 300 lbs / 136 kg

Armour:
Belt 2.00" / 51 mm, ends unarmoured
Belts cover 100 % of normal area
Main gun shields 2.00" / 51 mm, AA gun shields 1.00" / 25 mm, Light gun shields 1.00" / 25 mm
Armour deck 1.00" / 25 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 12,604 shp / 9,403 Kw = 24.00 kts
Range 6,500nm at 12.00 kts

Complement:
161 - 210

Cost:
£0.210 million / $0.838 million

Distribution of weights at normal displacement:
Armament: 37 tons, 1.7 %
Armour: 308 tons, 13.9 %
Belts: 139 tons, 6.3 %, Armament: 19 tons, 0.8 %, Armour Deck: 151 tons, 6.8 %
Conning Tower: 0 tons, 0.0 %, Torpedo bulkhead: 0 tons, 0.0 %
Machinery: 486 tons, 21.9 %
Hull, fittings & equipment: 931 tons, 42.0 %
Fuel, ammunition & stores: 357 tons, 16.1 %
Miscellaneous weights: 100 tons, 4.5 %

Metacentric height 1.5

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is adequate

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1.24
Shellfire needed to sink: 2,980 lbs / 1,352 Kg = 44.4 x 5.1 " / 130 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 0.9
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 56 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0.16
Relative quality as seaboat: 1.12

Hull form characteristics:
Block coefficient: 0.500
Sharpness coefficient: 0.33
Hull speed coefficient 'M': 8.67
'Natural speed' for length: 19.24 kts
Power going to wave formation at top speed: 51 %
Trim: 50
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 89.4 %
Relative accommodation and working space: 105.9 %
(Average = 100%)
Displacement factor: 132 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 1.21
(Structure weight / hull surface area: 69 lbs / square foot or 336 Kg / square metre)
Relative longitudinal hull strength: 1.32
(for 11.00 ft / 3.35 m average freeboard, freeboard adjustment -0.21 ft)
Relative composite hull strength: 1.22

Shonan Maru, Japan Fishery Security and Patrol Frigate laid down 1946

Displacement:
952 t light; 1,047 t standard; 1,442 t normal; 1,758 t full load

Dimensions: Length overall / water x beam x draught
229.75 ft / 217.00 ft x 33.50 ft x 15.60 ft (normal load)
70.03 m / 66.14 m x 10.21 m x 4.75 m

Armament:
4 - 2.95" / 75.0 mm guns (2x2 guns), 12.00lbs / 5.44kg shells, 1946 Model
Automatic rapid fire guns in deck mounts with hoists
on centreline ends, evenly spread
12 - 1.57" / 40.0 mm guns (2x6 guns), 2.00lbs / 0.91kg shells, 1946 Model
Anti-aircraft guns in deck mounts
on centreline ends, evenly spread, all raised mounts
Weight of broadside 72 lbs / 33 kg
Shells per gun, main battery: 1,380

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm - 1.00" / 25 mm
2nd: 1.00" / 25 mm - -

- Conning tower: 2.00" / 51 mm

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 7,232 shp / 5,395 Kw = 22.00 kts
Range 12,000nm at 15.00 kts
Bunker at max displacement = 711 tons

Complement:
116 - 152

Cost:
£0.479 million / $1.916 million

Distribution of weights at normal displacement:
Armament: 11 tons, 0.7%
Armour: 12 tons, 0.9%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 7 tons, 0.5%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 6 tons, 0.4%
Machinery: 181 tons, 12.5%
Hull, fittings & equipment: 448 tons, 31.1%
Fuel, ammunition & stores: 491 tons, 34.0%
Miscellaneous weights: 300 tons, 20.8%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2,240 lbs / 1,016 Kg = 174.0 x 3.0 " / 75 mm shells or 0.9 torpedoes
Stability (Unstable if below 1.00): 1.06
Metacentric height 1.1 ft / 0.3 m
Roll period: 13.5 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.12
Seaboat quality (Average = 1.00): 1.28

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.445
Length to Beam Ratio: 6.48 : 1
'Natural speed' for length: 17.60 kts
Power going to wave formation at top speed: 66 %
Trim (Max stability = 0, Max steadiness = 100): 39
Bow angle (Positive = bow angles forward): 29.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 23.00 ft / 7.01 m
- Forecastle (20%): 13.00 ft / 3.96 m
- Mid (50%): 13.00 ft / 3.96 m
- Quarterdeck (15%): 13.00 ft / 3.96 m
- Stern: 13.00 ft / 3.96 m
- Average freeboard: 13.80 ft / 4.21 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 74.2%
- Above water (accommodation/working, high = better): 102.4%
Waterplane Area: 4,797 Square feet or 446 Square metres
Displacement factor (Displacement / loading): 190%
Structure weight / hull surface area: 47 lbs/sq ft or 231 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.82
- Longitudinal: 5.89
- 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 rounds per gun (67t):
75mm guns: 1500 rounds per gun (40t)
40mm guns: 2000 rounds per gun (27t)

Ranges
4023 nm at 22 knots
5365 nm at 20 knots
7285 nm at 18 knots
12000 nm at 15 knots
21050 nm at 12 knots
32200 nm at 10 knots

Endurance
7 days, 14 hours, 51 minutes at 22 knots
11 days, 4 hours, 15 minutes at 20 knots
16 days, 20 hours, 43 minutes at 18 knots
33 days, 8 hours at 15 knots
73 days, 2 hours, 10 minutes at 12 knots
134 days, 4 hours at 10 knots

Fuel consumption (711 tons)
93.32 tons per day at 22 knots
63.61 tons per day at 20 knots
42.16 tons per day at 18 knots
21.33 tons per day at 15 knots
9.73 tons per day at 12 knots
5.30 tons per day at 10 knots

300 tons:
20 tons for Active Sonar
10 tons for Hydrophones
20 tons for Air Search Radar
10 tons for Surface Search Radar
8 tons for 75mm loading, training and elevation systems
4 tons for 40mm loading, training and elevation systems
4 tons for 2 Depth Charge Chutes
4 tons for 4 Depth Charge Throwers
20 tons for 60 Type 2 Depth Charges or 20 Type 1 Depth Charges
10 tons for damage control and fire suppression systems
5 tons for emergency diesel generators
10 tons for air condition system
46 tons for degauss coiling
100 tons for accommodation of 50 security officers
29 tons for various