WesWorld

This is the Cross-Guard Class. This battleship was quite hard to made because of the armor. I had never face the challenge to made a ship with this cuantities of armor. At the start the things went out of hand with the size to try to got more displacement. But at the end I found the way to balance the things and get almost the same ship in less length.






Cross Guard Class, Battleship laid down 1924


Displacement:
36.244 t light; 38.764 t standard; 41.546 t normal; 43.771 t full load


Dimensions: Length overall / water x beam x draught
736,87 ft / 711,94 ft x 101,71 ft (Bulges 113,19 ft) x 32,81 ft (normal load)
224,60 m / 217,00 m x 31,00 m (Bulges 34,50 m) x 10,00 m


Armament:
9 - 16,00" / 406 mm guns (3x3 guns), 2.048,00lbs / 928,96kg shells, 1924 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, majority aft, 1 raised mount aft - superfiring
12 - 6,00" / 152 mm guns (6x2 guns), 108,00lbs / 48,99kg shells, 1924 Model
Breech loading guns in deck mounts with hoists
on side, all amidships
8 - 4,00" / 102 mm guns in single mounts, 32,00lbs / 14,51kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, all aft
4 - 1,00" / 25,4 mm guns in single mounts, 0,50lbs / 0,23kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, all forward
24 - 0,50" / 12,7 mm guns (6x4 guns), 0,06lbs / 0,03kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 19.987 lbs / 9.066 kg
Shells per gun, main battery: 150


Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 13,8" / 350 mm 362,53 ft / 110,50 m 12,11 ft / 3,69 m
Ends: 1,57" / 40 mm 349,41 ft / 106,50 m 12,11 ft / 3,69 m
Upper: 7,87" / 200 mm 369,09 ft / 112,50 m 8,01 ft / 2,44 m
Main Belt covers 78 % of normal length


- Torpedo Bulkhead and Bulges:
7,87" / 200 mm 392,06 ft / 119,50 m 28,61 ft / 8,72 m


- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 15,7" / 400 mm 3,94" / 100 mm 13,0" / 330 mm
2nd: 2,36" / 60 mm 0,79" / 20 mm 2,36" / 60 mm
3rd: 1,18" / 30 mm - -
4th: 1,18" / 30 mm - -
5th: 1,18" / 30 mm - -


- Armour deck: 7,87" / 200 mm, Conning tower: 9,84" / 250 mm


Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 56.423 shp / 42.091 Kw = 23,00 kts
Range 5.500nm at 18,00 kts
Bunker at max displacement = 5.007 tons


Complement:
1.454 - 1.891


Cost:
£11,212 million / $44,848 million


Distribution of weights at normal displacement:
Armament: 2.498 tons, 6,0 %
Armour: 17.187 tons, 41,4 %
- Belts: 4.063 tons, 9,8 %
- Torpedo bulkhead: 3.268 tons, 7,9 %
- Armament: 2.241 tons, 5,4 %
- Armour Deck: 7.361 tons, 17,7 %
- Conning Tower: 254 tons, 0,6 %
Machinery: 1.858 tons, 4,5 %
Hull, fittings & equipment: 14.650 tons, 35,3 %
Fuel, ammunition & stores: 5.302 tons, 12,8 %
Miscellaneous weights: 50 tons, 0,1 %


Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
58.743 lbs / 26.645 Kg = 28,7 x 16,0 " / 406 mm shells or 13,3 torpedoes
Stability (Unstable if below 1.00): 1,24
Metacentric height 7,6 ft / 2,3 m
Roll period: 17,2 seconds
Steadiness - As gun platform (Average = 50 %): 55 %
- Recoil effect (Restricted arc if above 1.00): 0,37
Seaboat quality (Average = 1.00): 1,10


Hull form characteristics:
Hull has a flush deck
Block coefficient: 0,550
Length to Beam Ratio: 6,29 : 1
'Natural speed' for length: 26,68 kts
Power going to wave formation at top speed: 42 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 30,00 degrees
Stern overhang: 16,40 ft / 5,00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 14,76 ft / 4,50 m
- Forecastle (20 %): 13,12 ft / 4,00 m
- Mid (50 %): 19,69 ft / 6,00 m
- Quarterdeck (15 %): 13,12 ft / 4,00 m
- Stern: 13,12 ft / 4,00 m
- Average freeboard: 15,39 ft / 4,69 m
Ship tends to be wet forward


Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 76,9 %
- Above water (accommodation/working, high = better): 108,6 %
Waterplane Area: 50.533 Square feet or 4.695 Square metres
Displacement factor (Displacement / loading): 101 %
Structure weight / hull surface area: 210 lbs/sq ft or 1.024 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,99
- Longitudinal: 1,12
- Overall: 1,00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate

One thing I noted, both here and in your Inquebrantable design, is that you have some extremely heavy armour in your underwater protection scheme - a full 200mm here.

Springsharp doesn't do a great job explaining how a TDS works, nor giving you any ideas about what would be common in historical periods. But the idea is for a modest underwater armoured belt (between 5cm to 8cm) backed by a sizeable void space, 3-4 meters deep or more, per side. Springsharp 2 only calculates the belt, and not the depth of the void space - which is, in fact, the most important part of the entire system. In theory, when a torpedo hits the underwater belt, it detonates and penetrates the armour; it's very hard to use enough armour to actually prevent this. However, if the void space is deep enough, the force of the explosion does not compromise the inner bulkhead of the void space, thus protecting the vitals of the ship from flooding and further damage. (Additionally, if a torpedo is taken on one side of the ship, the void space on the other side can be counterflooded to reduce any list.)

One second comment that bears discussion: I note that, for these 1920s vessels, you've stuck with end and upper belts. In the 1920s, most historical navies actually ditched that idea for the "All or Nothing" scheme pioneered by the US Navy in the Standard-class battleships. See the linked video for a more thorough discussion of the specific idea. The end and upper armour belts were discarded as a result. I'd have to double check to be certain, but most of the capital ships built after the end of WWI either used All-or-Nothing, or trended heavily in that direction.

So, if I might offer some suggestions:
- Try reducing your TDS thickness to between, say, 6cm to 8cm
- Remove the end and upper belts entirely
- See if you can use the weight savings to raise the speed to 25-26 knots

Overall, I think the design is fairly decent, so I'd encourage you to keep working on it. :)

I agree with Brock on all points, though I'd also add any weight savings from reducing the torpedo bulkheads could be added to the Conning tower armor as well, though that may alter your stability somewhat.

Thanks to both of you. I will keep working on it.

Was interesting play with the armor of the barbette and the belt to get a reasonable seekeeping.




Cross Guard Class, Battleship laid down 1924

Displacement:
36.249 t light; 38.764 t standard; 41.546 t normal; 43.771 t full load

Dimensions: Length overall / water x beam x draught
737,82 ft / 711,94 ft x 101,71 ft (Bulges 113,19 ft) x 32,81 ft (normal load)
224,89 m / 217,00 m x 31,00 m (Bulges 34,50 m) x 10,00 m

Armament:
9 - 16,00" / 406 mm guns (3x3 guns), 2.048,00lbs / 928,96kg shells, 1924 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, majority aft, 1 raised mount aft - superfiring
12 - 6,00" / 152 mm guns (6x2 guns), 108,00lbs / 48,99kg shells, 1924 Model
Breech loading guns in deck mounts with hoists
on side, all amidships
8 - 3,50" / 88,9 mm guns in single mounts, 21,44lbs / 9,72kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, all aft
8 - 1,50" / 38,1 mm guns (4x2 guns), 1,69lbs / 0,77kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, all forward
24 - 0,99" / 25,1 mm guns (6x4 guns), 0,49lbs / 0,22kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
Weight of broadside 19.925 lbs / 9.038 kg
Shells per gun, main battery: 150

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 18,5" / 470 mm 411,75 ft / 125,50 m 12,11 ft / 3,69 m
Ends: Unarmoured
Main Belt covers 89 % of normal length

- Torpedo Bulkhead and Bulges:
3,15" / 80 mm 411,75 ft / 125,50 m 28,61 ft / 8,72 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 15,7" / 400 mm 4,33" / 110 mm 13,8" / 350 mm
2nd: 2,36" / 60 mm 0,79" / 20 mm 2,36" / 60 mm
3rd: 1,18" / 30 mm - -
4th: 1,18" / 30 mm - -
5th: 1,18" / 30 mm - -

- Armour deck: 8,66" / 220 mm, Conning tower: 11,81" / 300 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 83.570 shp / 62.343 Kw = 25,50 kts
Range 5.500nm at 18,00 kts
Bunker at max displacement = 5.007 tons

Complement:
1.454 - 1.891

Cost:
£11,579 million / $46,316 million

Distribution of weights at normal displacement:
Armament: 2.491 tons, 6,0 %
Armour: 16.216 tons, 39,0 %
- Belts: 4.086 tons, 9,8 %
- Torpedo bulkhead: 1.373 tons, 3,3 %
- Armament: 2.355 tons, 5,7 %
- Armour Deck: 8.097 tons, 19,5 %
- Conning Tower: 305 tons, 0,7 %
Machinery: 2.753 tons, 6,6 %
Hull, fittings & equipment: 14.740 tons, 35,5 %
Fuel, ammunition & stores: 5.297 tons, 12,7 %
Miscellaneous weights: 50 tons, 0,1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
52.763 lbs / 23.933 Kg = 25,8 x 16,0 " / 406 mm shells or 9,7 torpedoes
Stability (Unstable if below 1.00): 1,23
Metacentric height 7,5 ft / 2,3 m
Roll period: 17,3 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0,36
Seaboat quality (Average = 1.00): 1,00

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0,550
Length to Beam Ratio: 6,29 : 1
'Natural speed' for length: 26,68 kts
Power going to wave formation at top speed: 48 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 30,00 degrees
Stern overhang: 16,40 ft / 5,00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16,40 ft / 5,00 m
- Forecastle (20 %): 13,12 ft / 4,00 m
- Mid (50 %): 19,69 ft / 6,00 m
- Quarterdeck (15 %): 13,12 ft / 4,00 m
- Stern: 13,12 ft / 4,00 m
- Average freeboard: 15,52 ft / 4,73 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 85,3 %
- Above water (accommodation/working, high = better): 108,6 %
Waterplane Area: 50.533 Square feet or 4.695 Square metres
Displacement factor (Displacement / loading): 100 %
Structure weight / hull surface area: 211 lbs/sq ft or 1.029 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,99
- Longitudinal: 1,13
- Overall: 1,00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is adequate