WesWorld

Shimushu, Japan Kaibokan laid down 1941



Displacement:
880 t light; 934 t standard; 1,170 t normal; 1,359 t full load

Dimensions: Length overall / water x beam x draught
264.82 ft / 260.00 ft x 32.00 ft x 11.30 ft (normal load)
80.72 m / 79.25 m x 9.75 m x 3.44 m

Armament:
3 - 5.00" / 127 mm guns (2 mounts), 55.12lbs / 25.00kg shells, 1941 Model
Automatic rapid fire guns in deck mounts with hoists
on centreline ends, evenly spread
12 - 0.98" / 25.0 mm guns (4x3 guns), 0.57lbs / 0.26kg shells, 1941 Model
Anti-aircraft guns in deck mounts
on side ends, evenly spread, all raised mounts - superfiring
1 - 0.98" / 25.0 mm guns in single mounts, 0.57lbs / 0.26kg shells, 1941 Model
Anti-aircraft gun in deck mount
on centreline forward, 1 raised gun
3 - 0.98" / 25.0 mm guns (1x3 guns), 0.57lbs / 0.26kg shells, 1941 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
Weight of broadside 174 lbs / 79 kg
Shells per gun, main battery: 300

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 1.00" / 25 mm -
2nd: 1.00" / 25 mm - -
4th: 1.00" / 25 mm - -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 6,901 shp / 5,148 Kw = 22.00 kts
Range 6,000nm at 16.00 kts
Bunker at max displacement = 424 tons

Complement:
99 - 130

Cost:
£0.499 million / $1.997 million

Distribution of weights at normal displacement:
Armament: 29 tons, 2.5%
Armour: 18 tons, 1.5%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 18 tons, 1.5%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 0 tons, 0.0%
Machinery: 182 tons, 15.6%
Hull, fittings & equipment: 451 tons, 38.6%
Fuel, ammunition & stores: 290 tons, 24.8%
Miscellaneous weights: 200 tons, 17.1%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,536 lbs / 697 Kg = 24.6 x 5.0 " / 127 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 1.0 ft / 0.3 m
Roll period: 13.1 seconds
Steadiness - As gun platform (Average = 50 %): 60 %
- Recoil effect (Restricted arc if above 1.00): 0.31
Seaboat quality (Average = 1.00): 1.26

Hull form characteristics:
Hull has raised forecastle
Block coefficient: 0.436
Length to Beam Ratio: 8.13 : 1
'Natural speed' for length: 16.12 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 48
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 18.00 ft / 5.49 m
- Forecastle (20%): 17.00 ft / 5.18 m (10.00 ft / 3.05 m aft of break)
- Mid (30%): 10.00 ft / 3.05 m
- Quarterdeck (15%): 10.00 ft / 3.05 m
- Stern: 10.00 ft / 3.05 m
- Average freeboard: 11.48 ft / 3.50 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 89.8%
- Above water (accommodation/working, high = better): 100.9%
Waterplane Area: 5,247 Square feet or 487 Square metres
Displacement factor (Displacement / loading): 144%
Structure weight / hull surface area: 50 lbs/sq ft or 243 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.54
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is adequate
Good seaboat, rides out heavy weather easily

New ship design sent to Ship Design.

I am curious about the main armament specified in the design, "1941 Model Automatic rapid fire guns in deck mounts with hoists"

"Automatic rapid fire" is not, as far as I know, a selectable option in SS 2.1 - "Automatic" yes, but "Automatic rapid fire" no. What exactly is meant here?

Also, since these certainly appear to be escort vessels, I'd presume that the 200 tons of miscellaneous weight represents, in part, the A/S armament. What is the breakdown?

Quoted

Originally posted by BruceDuncan
"Automatic rapid fire" is not, as far as I know, a selectable option in SS 2.1 - "Automatic" yes, but "Automatic rapid fire" no. What exactly is meant here?

Automatic is what's in the GUI (the program interface), Automatic Rapid Fire is what the report will spit out with that option.

Quoted

Originally posted by ShinRa_Inc

Quoted

Originally posted by BruceDuncan
"Automatic rapid fire" is not, as far as I know, a selectable option in SS 2.1 - "Automatic" yes, but "Automatic rapid fire" no. What exactly is meant here?

Automatic is what's in the GUI (the program interface), Automatic Rapid Fire is what the report will spit out with that option.

Thank you for clarifying that point; I am still surprised by the decision to select such a weapon for what appears to be a low-end escort. It seems counter intuitive.

Quoted

What is the breakdown?

You know... that's a good question...

I was thinking about something along the lines of the Ukuru so for the mortar, the Depth Charge Projectors, Throwers and Chutes as well as the Depth Charges themselves, I would guess 66 tons. Electronics 95 tons. The rest for some minor things, including extra ammunition for the 25mm guns.

With Brock mentioning "gyroplanes", I'm kind of tempted to dump an Autogyro onto it as well, but...

...where to dump it? Granted my design is a bit longer than the Ukuru, but only 1.75m. Not enought to create space somewhere where an Autogyro could land so that idea seems to be out of the question.

... Something like the Fa 223A would be neat, but that thing has a span that is about 1/3 of the length of the vessel...

*goes off to design a bigger escort vessel*

... but before that, using MS Paint to count the pixels, I slightly tuned the Shimushu design a bit so the freeboard matches the freeboard as seen in the Ukuru picture (more or less). I also split up the main armament so the report gives an armoured single gun mount forward and an unarmoured twin gun mount aft rather than the "2 mounts" remark. Of course that meant that the light displacement changed by 3 tons which needed to be corrected (IIRC, SS2 assumes that there are 30 more 2nd gun shells than main gun shells; I would have to check that to be sure as well as the differences with 3rd, 4th and 5th guns). Removed excess HS by adding a bit of miscellaneous weight.

Shimushu, Japan Kaibokan laid down 1941

Displacement:
880 t light; 938 t standard; 1,174 t normal; 1,363 t full load

Dimensions: Length overall / water x beam x draught
264.41 ft / 260.00 ft x 32.00 ft x 11.30 ft (normal load)
80.59 m / 79.25 m x 9.75 m x 3.44 m

Armament:
1 - 5.00" / 127 mm guns in single mounts, 55.12lbs / 25.00kg shells, 1941 Model
Automatic rapid fire gun in a deck mount with hoist
on centreline forward
2 - 5.00" / 127 mm guns (1x2 guns), 55.12lbs / 25.00kg shells, 1941 Model
Automatic rapid fire guns in a deck mount with hoist
on centreline aft
12 - 0.98" / 25.0 mm guns (4x3 guns), 0.57lbs / 0.26kg shells, 1941 Model
Anti-aircraft guns in deck mounts
on side ends, evenly spread, all raised mounts - superfiring
1 - 0.98" / 25.0 mm guns in single mounts, 0.57lbs / 0.26kg shells, 1941 Model
Anti-aircraft gun in deck mount
on centreline forward, 1 raised gun
3 - 0.98" / 25.0 mm guns (1x3 guns), 0.57lbs / 0.26kg shells, 1941 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
Weight of broadside 174 lbs / 79 kg
Shells per gun, main battery: 300

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 1.00" / 25 mm -
3rd: 1.00" / 25 mm - -
5th: 1.00" / 25 mm - -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 6,920 shp / 5,162 Kw = 22.00 kts
Range 6,000nm at 16.00 kts
Bunker at max displacement = 425 tons

Complement:
99 - 130

Cost:
£0.500 million / $1.998 million

Distribution of weights at normal displacement:
Armament: 29 tons, 2.5%
Armour: 7 tons, 0.6%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 7 tons, 0.6%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 0 tons, 0.0%
Machinery: 183 tons, 15.6%
Hull, fittings & equipment: 431 tons, 36.7%
Fuel, ammunition & stores: 294 tons, 25.1%
Miscellaneous weights: 230 tons, 19.6%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,370 lbs / 621 Kg = 21.9 x 5.0 " / 127 mm shells or 0.7 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.1 ft / 0.3 m
Roll period: 12.9 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.23
Seaboat quality (Average = 1.00): 1.04

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.437
Length to Beam Ratio: 8.13 : 1
'Natural speed' for length: 16.12 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 48
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16.47 ft / 5.02 m
- Forecastle (25%): 14.76 ft / 4.50 m
- Mid (27%): 14.76 ft / 4.50 m (8.07 ft / 2.46 m aft of break)
- Quarterdeck (15%): 8.07 ft / 2.46 m
- Stern: 8.07 ft / 2.46 m
- Average freeboard: 10.05 ft / 3.06 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 92.7%
- Above water (accommodation/working, high = better): 83.8%
Waterplane Area: 5,252 Square feet or 488 Square metres
Displacement factor (Displacement / loading): 141%
Structure weight / hull surface area: 50 lbs/sq ft or 247 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.93
- Longitudinal: 2.01
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is cramped

So you took a historical ship, built it 3 yrs ahead of OTL, made it longer, wider, deeper, and faster while putting bigger guns on it (5" vs 12cm) yet it weighs less (938std vs 940std) than the OTL version. Hmm...somehow seems off to me. It's a nice ship, I just think w/ all things considered your version would come out heavier than OTL.

I know 2x2=5, but 1939-1941=3? That's a new one!

I simmed the Shimushu to begin with, which is a 1939 design. I wanted a slightly bigger version of that one, so I increased the three dimensions of the Shimushu and not of the Ukuru (which is 1943). I ended up below the Ukuru's displacement most likely because of that. On the other hand, because it is based on the Shimushu, it has Shimushu's 6000nm range, and not the 5000nm of the Ukuru. The thing is that I never bothered to look at the dimension and displacement stats of the other Kaibokan classes. I only looked at their weapons and ASW stuff.
At one point I was contemplating whether I should stick to the 3x1 layout or the slightly more unusual 1x2 and 1x1 of the Mikura (which is 1942). Because of the looks, I went for the latter. The photo of the Shisaka (which is 1944) was in my opinion the better looking photo of a vessel with such a gun layout on wiki so I used that one. I do not have the 120mm option so it is either 105mm or 5" and 5" was the closest option.

Quoted

Originally posted by Rooijen10
I know 2x2=5, but 1939-1941=3? That's a new one!

Well, you say it's based on the 1939 Shimushu in one post...but all the graphics you're using are of the later Ukuru. Specifically, the Ukuru with a '44-'45 fit. Such things tend to confuse and baffle us occidentals.

Quoted

Originally posted by Rooijen10
At one point I was contemplating whether I should stick to the 3x1 layout or the slightly more unusual 1x2 and 1x1 of the Mikura (which is 1942). Because of the looks, I went for the latter. The photo of the Shisaka (which is 1944) was in my opinion the better looking photo of a vessel with such a gun layout on wiki so I used that one. I do not have the 120mm option so it is either 105mm or 5" and 5" was the closest option.

I will point out that developing, designing, producing, and deploying two seperate automatic mounts (single and twin) for a low-cost escort....is rather counter-intuitive.

On that vein, I question the requirement of the automatic weapons in general; it's come up numerous times on the board that an ASW vessel has no real requirement for rapid, heavy fire.

I was going off the Ukuru, since that is the picture you posted. Ukuru was 940t Std, and smaller (L/B/W) than your SS. It's also the one that was newer (laid down late '43). Shimushu has a different layout than your ship, which has the same layout as Ukuru.

Quoted

you say it's based on the 1939 Shimushu in one post

The thing is that you should read the "it's" as "it was" and not as "it is". When you mess long enough with a design of HMS Hood, you may end up with something that more closely resembles KMS Bismarck. I think that that is one of the problems of this design. It is no longer the ship I started out with in SS2, and, adding the fact that I am looking a bit at the other classes of those escort ships and post pictures of the other classes, that is what is causing the confusion.

Quoted

it's come up numerous times on the board that an ASW vessel has no real requirement for rapid, heavy fire.

True, but I was thinking about the idea trying to force an enemy submarine to the surface as fast as possible (which was why I was looking at the Ukuru's ASW layout with its 16 DCTs) and have it submerge (permanently) even faster (which is why I was looking at the rapid, heavy fire option). the 105mm guns could possibly give me a 2x2 layout, a slightly higher ROF and thus more shells flying through the sky at a surfaced submarine.
Still, thinking of it now it might be a cheaper and better option to either use the 25mm guns to riddle the submarine full of holes, or add something like the 40mm or 50mm guns.

With the game Silent Service, I usually surfaced in order to engage the Kaibokans with the deck gun rather than wasting torpedoes on them...
... which didn't always go as planned. ^_^;;
Ah those were the days. Back then, those Kaibokans ruined my day when I tried to attack ships. Nowadays the idiotic opponents in Gran Turismo 5 who can't drive are the ones who ruin my day.

Quoted

I was going off the Ukuru, since that is the picture you posted.

I posted that because of the deckspace that the guns and ASW would take up if I were to go for such a ASW layout and the fact that if I were to add an autogyro, there would be no space to put it. Also, since I had that picture around, I used that one to base the freeboard on rather than the picture of the Shimushu.

What I mentioned about Hood and Bismarck is also true for the Shimushu and Ukuru but you end up a lot faster at the Ukuru than that you would end up at the Bismarck, especially if you decide to go for the main gun layout of the Mikura, which has the same layout as the Ukuru. Guess that's the difference between a 4 year gap and a 20 year gap.

Just in case you want to compare them, here are quick sims I made of the Shimushu, the Etorofu, the Mikura and the Ukuru, based on the wiki and warshipsww2.eu data. For simplicity, I did not bother to check the exact freeboards of all four classes and just use the one I already calculated. Whenever hull strength was left, I added miscellaneous weights until it was at 1.00.

Shimushu, Japan Escort ship laid down 1939

Displacement:
833 t light; 874 t standard; 1,116 t normal; 1,309 t full load

Dimensions: Length overall / water x beam x draught
254.41 ft / 250.00 ft x 29.86 ft x 10.01 ft (normal load)
77.55 m / 76.20 m x 9.10 m x 3.05 m

Armament:
3 - 4.72" / 120 mm guns in single mounts, 45.00lbs / 20.41kg shells, 1939 Model
Anti-aircraft guns in deck mounts with hoists
on centreline ends, majority aft, 1 raised mount aft
4 - 0.98" / 25.0 mm guns (2x2 guns), 0.48lbs / 0.22kg shells, 1939 Model
Anti-aircraft guns in deck mounts
on side, all forward, all raised mounts - superfiring
Weight of broadside 137 lbs / 62 kg
Shells per gun, main battery: 250

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 1.00" / 25 mm -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 4,529 shp / 3,379 Kw = 19.70 kts
Range 6,017nm at 16.00 kts
Bunker at max displacement = 435 tons

Complement:
96 - 125

Cost:
£0.367 million / $1.469 million

Distribution of weights at normal displacement:
Armament: 20 tons, 1.8%
Armour: 15 tons, 1.3%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 15 tons, 1.3%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 0 tons, 0.0%
Machinery: 123 tons, 11.0%
Hull, fittings & equipment: 411 tons, 36.8%
Fuel, ammunition & stores: 283 tons, 25.4%
Miscellaneous weights: 265 tons, 23.7%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,891 lbs / 858 Kg = 35.9 x 4.7 " / 120 mm shells or 0.9 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 1.0 ft / 0.3 m
Roll period: 12.5 seconds
Steadiness - As gun platform (Average = 50 %): 49 %
- Recoil effect (Restricted arc if above 1.00): 0.34
Seaboat quality (Average = 1.00): 1.52

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.523
Length to Beam Ratio: 8.37 : 1
'Natural speed' for length: 15.81 kts
Power going to wave formation at top speed: 55 %
Trim (Max stability = 0, Max steadiness = 100): 32
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16.47 ft / 5.02 m
- Forecastle (20%): 14.76 ft / 4.50 m
- Mid (50%): 14.76 ft / 4.50 m (8.07 ft / 2.46 m aft of break)
- Quarterdeck (15%): 8.07 ft / 2.46 m
- Stern: 8.07 ft / 2.46 m
- Average freeboard: 11.55 ft / 3.52 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 76.5%
- Above water (accommodation/working, high = better): 112.5%
Waterplane Area: 5,079 Square feet or 472 Square metres
Displacement factor (Displacement / loading): 163%
Structure weight / hull surface area: 46 lbs/sq ft or 225 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.60
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather



Etorofu, Japan Escort ship laid down 1942

Displacement:
828 t light; 870 t standard; 1,103 t normal; 1,289 t full load

Dimensions: Length overall / water x beam x draught
254.41 ft / 250.00 ft x 29.86 ft x 10.01 ft (normal load)
77.55 m / 76.20 m x 9.10 m x 3.05 m

Armament:
3 - 4.72" / 120 mm guns in single mounts, 45.00lbs / 20.41kg shells, 1942 Model
Anti-aircraft guns in deck mounts with hoists
on centreline ends, majority aft, 1 raised mount aft
4 - 0.98" / 25.0 mm guns (2x2 guns), 0.48lbs / 0.22kg shells, 1942 Model
Anti-aircraft guns in deck mounts
on side, all forward, all raised mounts - superfiring
Weight of broadside 137 lbs / 62 kg
Shells per gun, main battery: 250

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 1.00" / 25 mm -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 4,483 shp / 3,344 Kw = 19.70 kts
Range 6,017nm at 16.00 kts
Bunker at max displacement = 420 tons

Complement:
95 - 124

Cost:
£0.396 million / $1.583 million

Distribution of weights at normal displacement:
Armament: 20 tons, 1.8%
Armour: 15 tons, 1.3%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 15 tons, 1.3%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 0 tons, 0.0%
Machinery: 117 tons, 10.6%
Hull, fittings & equipment: 408 tons, 37.0%
Fuel, ammunition & stores: 275 tons, 24.9%
Miscellaneous weights: 269 tons, 24.4%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,870 lbs / 848 Kg = 35.5 x 4.7 " / 120 mm shells or 0.9 torpedoes
Stability (Unstable if below 1.00): 1.11
Metacentric height 1.0 ft / 0.3 m
Roll period: 12.6 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.35
Seaboat quality (Average = 1.00): 1.55

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.517
Length to Beam Ratio: 8.37 : 1
'Natural speed' for length: 15.81 kts
Power going to wave formation at top speed: 55 %
Trim (Max stability = 0, Max steadiness = 100): 32
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16.47 ft / 5.02 m
- Forecastle (20%): 14.76 ft / 4.50 m
- Mid (50%): 14.76 ft / 4.50 m (8.07 ft / 2.46 m aft of break)
- Quarterdeck (15%): 8.07 ft / 2.46 m
- Stern: 8.07 ft / 2.46 m
- Average freeboard: 11.55 ft / 3.52 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 76.2%
- Above water (accommodation/working, high = better): 113.0%
Waterplane Area: 5,050 Square feet or 469 Square metres
Displacement factor (Displacement / loading): 163%
Structure weight / hull surface area: 46 lbs/sq ft or 224 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.61
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather



Mikura, Japan Escort ship laid down 1942

Displacement:
898 t light; 940 t standard; 1,138 t normal; 1,296 t full load

Dimensions: Length overall / water x beam x draught
258.68 ft / 254.27 ft x 29.86 ft x 10.04 ft (normal load)
78.85 m / 77.50 m x 9.10 m x 3.06 m

Armament:
3 - 4.72" / 120 mm guns (2 mounts), 45.00lbs / 20.41kg shells, 1942 Model
Anti-aircraft guns in deck mounts with hoists
on centreline ends, evenly spread
4 - 0.98" / 25.0 mm guns (2x2 guns), 0.48lbs / 0.22kg shells, 1942 Model
Anti-aircraft guns in deck mounts
on side, all forward, all raised mounts - superfiring
Weight of broadside 137 lbs / 62 kg
Shells per gun, main battery: 250

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 1.00" / 25 mm -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 4,359 shp / 3,252 Kw = 19.50 kts
Range 5,000nm at 16.00 kts
Bunker at max displacement = 356 tons

Complement:
97 - 127

Cost:
£0.408 million / $1.634 million

Distribution of weights at normal displacement:
Armament: 20 tons, 1.8%
Armour: 15 tons, 1.3%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 15 tons, 1.3%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 0 tons, 0.0%
Machinery: 114 tons, 10.0%
Hull, fittings & equipment: 415 tons, 36.5%
Fuel, ammunition & stores: 240 tons, 21.1%
Miscellaneous weights: 334 tons, 29.4%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,814 lbs / 823 Kg = 34.4 x 4.7 " / 120 mm shells or 0.8 torpedoes
Stability (Unstable if below 1.00): 1.07
Metacentric height 0.9 ft / 0.3 m
Roll period: 13.0 seconds
Steadiness - As gun platform (Average = 50 %): 51 %
- Recoil effect (Restricted arc if above 1.00): 0.33
Seaboat quality (Average = 1.00): 1.60

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.523
Length to Beam Ratio: 8.52 : 1
'Natural speed' for length: 15.95 kts
Power going to wave formation at top speed: 54 %
Trim (Max stability = 0, Max steadiness = 100): 32
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16.47 ft / 5.02 m
- Forecastle (20%): 14.76 ft / 4.50 m
- Mid (50%): 14.76 ft / 4.50 m (8.07 ft / 2.46 m aft of break)
- Quarterdeck (15%): 8.07 ft / 2.46 m
- Stern: 8.07 ft / 2.46 m
- Average freeboard: 11.55 ft / 3.52 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 79.1%
- Above water (accommodation/working, high = better): 113.2%
Waterplane Area: 5,164 Square feet or 480 Square metres
Displacement factor (Displacement / loading): 154%
Structure weight / hull surface area: 46 lbs/sq ft or 224 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.52
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather



Ukuru, Japan Escort ship laid down 1943

Displacement:
898 t light; 940 t standard; 1,136 t normal; 1,292 t full load

Dimensions: Length overall / water x beam x draught
258.68 ft / 254.27 ft x 29.86 ft x 10.04 ft (normal load)
78.85 m / 77.50 m x 9.10 m x 3.06 m

Armament:
3 - 4.72" / 120 mm guns (2 mounts), 45.00lbs / 20.41kg shells, 1943 Model
Anti-aircraft guns in deck mounts with hoists
on centreline ends, evenly spread
4 - 0.98" / 25.0 mm guns (2x2 guns), 0.48lbs / 0.22kg shells, 1943 Model
Anti-aircraft guns in deck mounts
on side, all forward, all raised mounts - superfiring
Weight of broadside 137 lbs / 62 kg
Shells per gun, main battery: 250

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 1.00" / 25 mm -

Machinery:
Diesel Internal combustion motors,
Geared drive, 2 shafts, 4,352 shp / 3,247 Kw = 19.50 kts
Range 5,000nm at 16.00 kts
Bunker at max displacement = 352 tons

Complement:
97 - 127

Cost:
£0.419 million / $1.675 million

Distribution of weights at normal displacement:
Armament: 20 tons, 1.8%
Armour: 15 tons, 1.3%
- Belts: 0 tons, 0.0%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 15 tons, 1.3%
- Armour Deck: 0 tons, 0.0%
- Conning Tower: 0 tons, 0.0%
Machinery: 112 tons, 9.9%
Hull, fittings & equipment: 416 tons, 36.6%
Fuel, ammunition & stores: 238 tons, 20.9%
Miscellaneous weights: 335 tons, 29.5%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,816 lbs / 824 Kg = 34.4 x 4.7 " / 120 mm shells or 0.8 torpedoes
Stability (Unstable if below 1.00): 1.07
Metacentric height 0.9 ft / 0.3 m
Roll period: 13.0 seconds
Steadiness - As gun platform (Average = 50 %): 51 %
- Recoil effect (Restricted arc if above 1.00): 0.33
Seaboat quality (Average = 1.00): 1.60

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.522
Length to Beam Ratio: 8.52 : 1
'Natural speed' for length: 15.95 kts
Power going to wave formation at top speed: 54 %
Trim (Max stability = 0, Max steadiness = 100): 32
Bow angle (Positive = bow angles forward): 15.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16.47 ft / 5.02 m
- Forecastle (20%): 14.76 ft / 4.50 m
- Mid (50%): 14.76 ft / 4.50 m (8.07 ft / 2.46 m aft of break)
- Quarterdeck (15%): 8.07 ft / 2.46 m
- Stern: 8.07 ft / 2.46 m
- Average freeboard: 11.55 ft / 3.52 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 78.9%
- Above water (accommodation/working, high = better): 113.1%
Waterplane Area: 5,159 Square feet or 479 Square metres
Displacement factor (Displacement / loading): 155%
Structure weight / hull surface area: 46 lbs/sq ft or 224 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.53
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Quoted

Originally posted by Rooijen10
With the game Silent Service, I usually surfaced in order to engage the Kaibokans with the deck gun rather than wasting torpedoes on them...
... which didn't always go as planned. ^_^;;
Ah those were the days. Back then, those Kaibokans ruined my day when I tried to attack ships. Nowadays the idiotic opponents in Gran Turismo 5 who can't drive are the ones who ruin my day.

You should try Battlestations Midway/Pacific :B

Quoted

Originally posted by Rooijen10

Quoted

you say it's based on the 1939 Shimushu in one post

The thing is that you should read the "it's" as "it was" and not as "it is". When you mess long enough with a design of HMS Hood, you may end up with something that more closely resembles KMS Bismarck. I think that that is one of the problems of this design. It is no longer the ship I started out with in SS2, and, adding the fact that I am looking a bit at the other classes of those escort ships and post pictures of the other classes, that is what is causing the confusion.

Quoted

it's come up numerous times on the board that an ASW vessel has no real requirement for rapid, heavy fire.

True, but I was thinking about the idea trying to force an enemy submarine to the surface as fast as possible (which was why I was looking at the Ukuru's ASW layout with its 16 DCTs) and have it submerge (permanently) even faster (which is why I was looking at the rapid, heavy fire option). the 105mm guns could possibly give me a 2x2 layout, a slightly higher ROF and thus more shells flying through the sky at a surfaced submarine.
Still, thinking of it now it might be a cheaper and better option to either use the 25mm guns to riddle the submarine full of holes, or add something like the 40mm or 50mm guns.

With the game Silent Service, I usually surfaced in order to engage the Kaibokans with the deck gun rather than wasting torpedoes on them...
... which didn't always go as planned. ^_^;;
Ah those were the days. Back then, those Kaibokans ruined my day when I tried to attack ships. Nowadays the idiotic opponents in Gran Turismo 5 who can't drive are the ones who ruin my day.

Quoted

I was going off the Ukuru, since that is the picture you posted.

I posted that because of the deckspace that the guns and ASW would take up if I were to go for such a ASW layout and the fact that if I were to add an autogyro, there would be no space to put it. Also, since I had that picture around, I used that one to base the freeboard on rather than the picture of the Shimushu.

What I mentioned about Hood and Bismarck is also true for the Shimushu and Ukuru but you end up a lot faster at the Ukuru than that you would end up at the Bismarck, especially if you decide to go for the main gun layout of the Mikura, which has the same layout as the Ukuru. Guess that's the difference between a 4 year gap and a 20 year gap.

What I find interesting is the apparent recognition by the IJN that specialized escort ships are vital to the survival of Japan; a lesson that in the OTL the IJN never recognized until it was too late. This is no doubt a wise course, and - as Wesworld is an alternate history - the IJN is not obligated to follow OTL doctrine.

Basing a design on a doctrine that *seems* to to work in a computer game does strike me as asking a lot however. I would agree with ShinRa that developing large-caliber automatic weapons for such vessels would not be cost effective, and that lighter, existing weaponry would be sufficiently effective in riddling a surfaced submarine.

Quoted

Originally posted by BruceDuncan
What I find interesting is the apparent recognition by the IJN that specialized escort ships are vital to the survival of Japan; a lesson that in the OTL the IJN never recognized until it was too late.

Indeed.

I also tend to think, though, that acquiring a rapid-fire gun for killing submarines is rather silly. If the submarine is surfaced, it's dead. Any shots that hit it will prevent it from submerging (more than once); so any gun will work so long as it actually hits.

Good bad or indifferent, my O-8 class has 20mm 'conning tower' armor intended to indicate the sail has armor. The point of the armor is more intended as anti-strafing than anti-ship, but would probably make light automatic HE fused weapons at range useless for 'riddling' them.

Quoted

Originally posted by Kaiser Kirk
Good bad or indifferent, my O-8 class has 20mm 'conning tower' armor intended to indicate the sail has armor. The point of the armor is more intended as anti-strafing than anti-ship, but would probably make light automatic HE fused weapons at range useless for 'riddling' them.

For riddling the Conning Tower, maybe. The rest of the boat is, presumably, as unarmoured as your usual sub. Either from hitting the hull itself, or fragments from hitting the conning tower, I'd still expect some notable effects from such a hit.

I think you're quire correct. However it shouldn't take much distance for the sub to be "hull down" and the hull is the first thing to submerge once diving commences. Small HE rounds really shouldn't produce much in the way of shrapnel that would compromise a pressure hull though. I had considered an 'upper belt', but the sail is far and away the easiest thing to be hit, and a visual focal point for aim so that's all I bothered with. Another ode to the Dutch proclivity to armor things.

On the other hand, if I recall correctly that class also has casement torpedoes, which gives the potential of a nice *boom*

I was thinking you'd end up with holes in the ballast and fuel tanks, among other things, too.

Re-simmed the Hiyo in SS2. Like I said, I thought I had done that, but apparently that was not the case. Took me 5 minutes to re-sim it. Took me 5 hours to determine a miscellaneous weights breakdown for those 20,000 tons. Coming up with things like a shinto shrine, a coin operated laundromat and flight deck BBQ equipment is a good indication of me getting desparate to come up with ideas.

While I was busy, I was thinking of making certain aspects of the miscellaneous weights fixed (as you can see below). Not sure if it is accurate or if it would work properly on smaller ships and perhaps some things would need a fixed minimum (like the 25 tons of the planes).


Hiyo, Japan Carrier laid down 1940

Displacement:
47,000 t light; 48,381 t standard; 52,985 t normal; 56,668 t full load

Dimensions: Length overall / water x beam x draught
905.69 ft / 876.00 ft x 108.00 ft x 35.00 ft (normal load)
276.06 m / 267.00 m x 32.92 m x 10.67 m

Armament:
8 - 5.00" / 127 mm guns (4x2 guns), 55.12lbs / 25.00kg shells, 1940 Model
Automatic rapid fire guns in deck mounts with hoists
on centreline ends, evenly spread, 2 raised mounts - superfiring
16 - 4.13" / 105 mm guns (8x2 guns), 34.00lbs / 15.42kg shells, 1940 Model
Automatic rapid fire guns in deck mounts with hoists
on side, all amidships
32 - 1.57" / 40.0 mm guns (4x8 guns), 2.00lbs / 0.91kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 3 raised mounts
51 - 0.98" / 25.0 mm guns (17x3 guns), 0.57lbs / 0.26kg shells, 1940 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
32 - 0.52" / 13.2 mm guns (4x8 guns), 0.09lbs / 0.04kg shells, 1940 Model
Machine guns in deck mounts
on centreline ends, evenly spread
Weight of broadside 1,081 lbs / 490 kg
Shells per gun, main battery: 450

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 6.00" / 152 mm 650.00 ft / 198.12 m 14.00 ft / 4.27 m
Ends: Unarmoured
Main Belt covers 114% of normal length

- Torpedo Bulkhead:
2.75" / 70 mm 650.00 ft / 198.12 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: 2.00" / 51 mm 1.00" / 25 mm 2.00" / 51 mm
3rd: 1.00" / 25 mm 1.00" / 25 mm -
4th: 1.00" / 25 mm 1.00" / 25 mm -
5th: 0.50" / 13 mm 0.50" / 13 mm -

- Armour deck: 3.25" / 83 mm, Conning tower: 2.75" / 70 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 165,587 shp / 123,528 Kw = 31.00 kts
Range 15,000nm at 15.00 kts
Bunker at max displacement = 8,287 tons

Complement:
1,746 - 2,270

Cost:
£14.450 million / $57.801 million

Distribution of weights at normal displacement:
Armament: 171 tons, 0.3%
Armour: 8,855 tons, 16.7%
- Belts: 2,269 tons, 4.3%
- Torpedo bulkhead: 2,183 tons, 4.1%
- Armament: 147 tons, 0.3%
- Armour Deck: 4,173 tons, 7.9%
- Conning Tower: 84 tons, 0.2%
Machinery: 4,427 tons, 8.4%
Hull, fittings & equipment: 13,546 tons, 25.6%
Fuel, ammunition & stores: 5,986 tons, 11.3%
Miscellaneous weights: 20,000 tons, 37.7%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
71,598 lbs / 32,476 Kg = 1,145.6 x 5.0 " / 127 mm shells or 11.2 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 6.5 ft / 2.0 m
Roll period: 17.9 seconds
Steadiness - As gun platform (Average = 50 %): 52 %
- Recoil effect (Restricted arc if above 1.00): 0.03
Seaboat quality (Average = 1.00): 1.37

Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.560
Length to Beam Ratio: 8.11 : 1
'Natural speed' for length: 34.11 kts
Power going to wave formation at top speed: 50 %
Trim (Max stability = 0, Max steadiness = 100): 38
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: 44.50 ft / 13.56 m
- Forecastle (15%): 23.50 ft / 7.16 m
- Mid (55%): 23.50 ft / 7.16 m
- Quarterdeck (15%): 23.50 ft / 7.16 m
- Stern: 23.50 ft / 7.16 m
- Average freeboard: 24.76 ft / 7.55 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 88.1%
- Above water (accommodation/working, high = better): 177.9%
Waterplane Area: 69,406 Square feet or 6,448 Square metres
Displacement factor (Displacement / loading): 136%
Structure weight / hull surface area: 139 lbs/sq ft or 680 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.99
- Longitudinal: 1.00
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Good seaboat, rides out heavy weather easily

- 14400 tons for 120 planes (120 tons per aircraft)
- 750 tons for 30 spare planes in crates (25 tons per aircraft)
- 1000 tons additional aircraft ordnance
- 480 tons for spare parts (4 tons per operational aircraft)
- 390 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
- 240 tons for flight operations center (2 tons per operational aircraft)
- 120 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
- 120 tons for an additional 3360 105mm rounds (for 750 rounds per gun)
- 25 tons for an additional 14720 40mm rounds (for 1000 rounds per gun)
- 35 tons for an additional 48960 25mm rounds (for 1500 rounds per gun)
- 10 tons for an additional 62720 13.2mm rounds (for 2500 rounds per gun)
- 470 tons for damage control and fire suppression systems (1 ton per 100 tons light displacement)
- 118 tons emergency diesel generators (1 ton per 400 tons light displacement)
- 470 tons for air condition system (1 ton per 100 tons light displacement)
- 182 tons for degaussing coils (1 ton per 5 feet of length (oa))