Logi's Design Studies

[Logi]

Now build a battlecruiser from scratch, how does it look?

EDIT: Noticed I put the midship turrets in singles by mistake.

JunFai, RRC Battlecruiser laid down 1918 (Engine 1916)

Displacement:
   20,000 t light; 21,206 t standard; 22,546 t normal; 23,618 t full load

Dimensions: Length overall / water x beam x draught
   630.00 ft / 620.00 ft x 85.00 ft x 27.00 ft (normal load)
   192.02 m / 188.98 m x 25.91 m  x 8.23 m

Armament:
      8 - 12.00" / 305 mm guns (4x2 guns), 1,040.00lbs / 471.74kg shells, 1918 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      4 - 12.00" / 305 mm guns (2x2 guns), 1,040.00lbs / 471.74kg shells, 1918 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, all amidships
      16 - 4.13" / 105 mm guns (8x2 guns), 35.32lbs / 16.02kg shells, 1918 Model
     Quick firing guns in deck mounts
     on side, evenly spread
      4 - 2.95" / 75.0 mm guns (2x2 guns), 12.87lbs / 5.84kg shells, 1918 Model
     Anti-aircraft guns in deck mounts
     on centreline, evenly spread
   Weight of broadside 13,097 lbs / 5,941 kg
   Shells per gun, main battery: 100
   9 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   10.0" / 254 mm   387.00 ft / 117.96 m   17.00 ft / 5.18 m
   Ends:   Unarmoured
     Main Belt covers 96 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   10.0" / 254 mm         -         9.00" / 229 mm
   2nd:   10.0" / 254 mm         -         9.00" / 229 mm
   3rd:   1.00" / 25 mm         -               -
   4th:   1.00" / 25 mm         -               -

   - Armour deck: 2.00" / 51 mm, Conning tower: 3.00" / 76 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 3 shafts, 63,781 shp / 47,581 Kw = 26.00 kts
   Range 8,000nm at 12.00 kts
   Bunker at max displacement = 2,412 tons

Complement:
   919 - 1,195

Cost:
   £4.372 million / $17.489 million

Distribution of weights at normal displacement:
   Armament: 1,373 tons, 6.1 %
   Armour: 6,417 tons, 28.5 %
      - Belts: 2,854 tons, 12.7 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 2,145 tons, 9.5 %
      - Armour Deck: 1,367 tons, 6.1 %
      - Conning Tower: 52 tons, 0.2 %
   Machinery: 2,376 tons, 10.5 %
   Hull, fittings & equipment: 9,516 tons, 42.2 %
   Fuel, ammunition & stores: 2,546 tons, 11.3 %
   Miscellaneous weights: 318 tons, 1.4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     25,805 lbs / 11,705 Kg = 29.9 x 12.0 " / 305 mm shells or 2.8 torpedoes
   Stability (Unstable if below 1.00): 1.09
   Metacentric height 4.6 ft / 1.4 m
   Roll period: 16.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.83
   Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
   Hull has low quarterdeck
   Block coefficient: 0.555
   Length to Beam Ratio: 7.29 : 1
   'Natural speed' for length: 24.90 kts
   Power going to wave formation at top speed: 50 %
   Trim (Max stability = 0, Max steadiness = 100): 48
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 1.99 ft / 0.61 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      22.00 ft / 6.71 m
      - Forecastle (20 %):   19.00 ft / 5.79 m
      - Mid (50 %):      17.00 ft / 5.18 m
      - Quarterdeck (15 %):   12.00 ft / 3.66 m (17.00 ft / 5.18 m before break)
      - Stern:      12.00 ft / 3.66 m
      - Average freeboard:   17.19 ft / 5.24 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 82.3 %
      - Above water (accommodation/working, high = better): 117.9 %
   Waterplane Area: 36,937 Square feet or 3,432 Square metres
   Displacement factor (Displacement / loading): 100 %
   Structure weight / hull surface area: 184 lbs/sq ft or 898 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.96
      - Longitudinal: 1.40
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is adequate

Main Belt is Sloped 20 Degrees (External) - So the vertical length of such a belt is 16 feet - the main belt is really 10.6" thick H.

[Tanthalas]

crowded... It looks crowded

[Sachmle]

PLEASE...PLEASE....BUILD IT!!! I would forever (Ok, about 20mins if/when we fight) be in your debt.

- Gun armour:
Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
Main:10.0"/254mm	-	9.00"/229mm
2nd:10.0"/254mm	-	9.00"/229mm

Open mounts for MB Turrets, novel approach. I like it! (cuz you'd be easy to GT)

[Logi]

Crap! I knew there was something missing...

JunFai, RRC Battlecruiser laid down 1918 (Engine 1916)

Displacement:
   20,000 t light; 21,207 t standard; 22,543 t normal; 23,612 t full load

Dimensions: Length overall / water x beam x draught
   630.00 ft / 620.00 ft x 85.00 ft x 28.00 ft (normal load)
   192.02 m / 188.98 m x 25.91 m  x 8.53 m

Armament:
      8 - 12.00" / 305 mm guns (4x2 guns), 1,040.00lbs / 471.74kg shells, 1918 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      4 - 12.00" / 305 mm guns (2x2 guns), 1,040.00lbs / 471.74kg shells, 1918 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, all amidships
      16 - 4.13" / 105 mm guns (8x2 guns), 35.32lbs / 16.02kg shells, 1918 Model
     Quick firing guns in deck mounts
     on side, evenly spread
      4 - 2.95" / 75.0 mm guns (2x2 guns), 12.87lbs / 5.84kg shells, 1918 Model
     Anti-aircraft guns in deck mounts
     on centreline, evenly spread
   Weight of broadside 13,097 lbs / 5,941 kg
   Shells per gun, main battery: 100
   9 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   10.0" / 254 mm   369.00 ft / 112.47 m   17.00 ft / 5.18 m
   Ends:   Unarmoured
     Main Belt covers 92 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   10.0" / 254 mm   7.00" / 178 mm      9.00" / 229 mm
   2nd:   10.0" / 254 mm   7.00" / 178 mm      9.00" / 229 mm
   3rd:   1.00" / 25 mm   1.00" / 25 mm            -
   4th:   1.00" / 25 mm   1.00" / 25 mm            -

   - Armour deck: 2.00" / 51 mm, Conning tower: 3.00" / 76 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 3 shafts, 63,203 shp / 47,149 Kw = 26.00 kts
   Range 8,000nm at 12.00 kts
   Bunker at max displacement = 2,405 tons

Complement:
   919 - 1,195

Cost:
   £4.366 million / $17.465 million

Distribution of weights at normal displacement:
   Armament: 1,373 tons, 6.1 %
   Armour: 6,407 tons, 28.4 %
      - Belts: 2,745 tons, 12.2 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 2,269 tons, 10.1 %
      - Armour Deck: 1,341 tons, 6.0 %
      - Conning Tower: 52 tons, 0.2 %
   Machinery: 2,355 tons, 10.4 %
   Hull, fittings & equipment: 9,544 tons, 42.3 %
   Fuel, ammunition & stores: 2,543 tons, 11.3 %
   Miscellaneous weights: 321 tons, 1.4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     25,510 lbs / 11,571 Kg = 29.5 x 12.0 " / 305 mm shells or 2.8 torpedoes
   Stability (Unstable if below 1.00): 1.07
   Metacentric height 4.5 ft / 1.4 m
   Roll period: 16.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.84
   Seaboat quality  (Average = 1.00): 1.06

Hull form characteristics:
   Hull has low quarterdeck
   Block coefficient: 0.535
   Length to Beam Ratio: 7.29 : 1
   'Natural speed' for length: 24.90 kts
   Power going to wave formation at top speed: 50 %
   Trim (Max stability = 0, Max steadiness = 100): 47
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 1.99 ft / 0.61 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      22.00 ft / 6.71 m
      - Forecastle (20 %):   19.00 ft / 5.79 m
      - Mid (50 %):      17.00 ft / 5.18 m
      - Quarterdeck (15 %):   12.00 ft / 3.66 m (17.00 ft / 5.18 m before break)
      - Stern:      12.00 ft / 3.66 m
      - Average freeboard:   17.19 ft / 5.24 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 82.0 %
      - Above water (accommodation/working, high = better): 115.8 %
   Waterplane Area: 36,256 Square feet or 3,368 Square metres
   Displacement factor (Displacement / loading): 101 %
   Structure weight / hull surface area: 185 lbs/sq ft or 906 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.46
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is adequate

Main Belt is Sloped 20 Degrees (External) - So the vertical length of such a belt is 16 feet - the main belt is really 10.6" thick H.

[Walter]

Open mounts for MB Turrets, novel approach.

No doubt China's idea of air conditioning for the main turrets. :D

[Tanthalas]

I restate my point that it looks awfull crowded.  the 6 twin 12" mounts is going to eat alot of deck space (see USS Wyoming if you doubt me) then the 3 tripple torp launchers all the deck mounts, Im just not sure it would all fit.

[Logi]

Ok let's examine.

The two AA guns are mounted on the smokestacks (I saw this something, forgot where) so it's not a problem.

The USS Wyoming's turret has a diameter of almost 25 ft. The gun itself is 40 ft long.

Since the gun is not superfiring that means + (40-25) ft to the OA Length of USS Wyoming.

That comes to 577 feet.

---------------------

Superstructure in USS Wyoming is roughly 140' long.

There are 8 105mm guns to be placed at the sides of this. That makes 4 guns per side. Each 105mm/55 gun is ~19'. Say I place the front two 5' apart and the back two 5' (I'm taking as a side). That comes to a total of 86'.

Subtract from superstructure length. 54' Left.

Take it each set of triple torp launchers is 23' long.

Total length of torpedo tubes with 1' of space between each is 71'. I'm lacking 17' on the superstructure!

But wait! The modified USS Wyoming designs is 577'. My design is 620' long. That's an addition of 63'!

Subtract the needed 17' from this and we get 46' left over.

Take it that the higher speed necessitates a larger volume and smokestacks. The former is solved because the USS Wyoming has a 86:14 coal:oil ratio in its bunker. This design uses only oil. Oil takes less space than coal.

For the smokestacks, we have, basically 23' of expansion for each stack (it obviously won't need that much). And there you have it.

It's a bit crowded, but everything fits nicely.

[Guinness]

Where do the 105mm deck mounts go?

Wyoming's secondary battery was all casemates below the main deck line...

[Logi]

Next to the superstructure as I said.

[Guinness]

My point was apparently too subtle. I wish I had the time at the moment to do a rough sketch, but I agree that there is insufficient deckspace for the primary and secondary armament, assuming the primary armament would have useful arcs.

Assuming those 105's are 45 caliber, we can expect they'd be about 4.75m long. That's roughly 15.5 feet. We should also assume that the crew needs at least a 3m or 9 foot working circle for the crew, which means you'd need somewhere around an extra meter or meter and a half behind the gun. So let's assume the length of the whole installation viewed from abeam would be 6 meters or between 19.5 and 20 feet. So assuming that the secondary battery guns arcs don't overlap (which is a good idea for a number of reasons), you'll need at least 48 meters of length, or 157 feet just for the secondary battery. This is not taking into account any allowances related to the main battery arcs to deal with blast.

And that's just the secondary battery.

[Logi]

The 105 are 55 caliber. That's roughly 19' as stated before.

I gave all the guns 5' working space. However, I have 46' left over after adding everything. I can use this to give all the secondary batteries enough working space.

I was thinking there is an aft and fore bridge. There are two secondary batteries for the aft and fore bridge per side.

Say I gave that 46' to the superstructure. The superstructure is now 196' long. I divd that directly into half and get 98' per part.

Work into the secondary guns and their working space = 56' directly for the guns and working space per two guns.

That means I have 42' per Fore or Aft bridge to play with the Secondaries' position so as to take it out of the main battery's firing arc.

----------------------------------------------

Say it simply the space for the secondary is the space for the superstructure. The superstructure is 196' long. You said I need 157' just for the secondary. I see no problem here.

[Tanthalas]

Logi you dont have 620' to work with... you have 369' to work with.  The Length of the Main belt where unless your looking to blow the hell up all your armor is located.  Im not personaly sure all 6 12" turrets will fit in that space without including everything else you have/need to put there

[Logi]

You're right :-\ Removed one gun in exchange for better armour overall.

JunFai, RRC Battlecruiser laid down 1918 (Engine 1916)

Displacement:
   20,000 t light; 21,079 t standard; 22,410 t normal; 23,475 t full load

Dimensions: Length overall / water x beam x draught
   630.00 ft / 620.00 ft x 85.00 ft x 28.00 ft (normal load)
   192.02 m / 188.98 m x 25.91 m  x 8.53 m

Armament:
     8 - 12.00" / 305 mm guns (4x2 guns), 1,040.00lbs / 471.74kg shells, 1918 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
     2 - 12.00" / 305 mm guns in single mounts, 1,040.00lbs / 471.74kg shells, 1918 Model
     Breech loading guns in turrets (on barbettes)
     on centreline, all amidships
     16 - 4.13" / 105 mm guns (8x2 guns), 35.32lbs / 16.02kg shells, 1918 Model
     Quick firing guns in deck mounts
     on side, evenly spread
     4 - 2.95" / 75.0 mm guns (2x2 guns), 12.87lbs / 5.84kg shells, 1918 Model
     Anti-aircraft guns in deck mounts
     on centreline, evenly spread
   Weight of broadside 11,017 lbs / 4,997 kg
   Shells per gun, main battery: 100
   9 - 21.0" / 533.4 mm above water torpedoes

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   12.0" / 305 mm   407.00 ft / 124.05 m   17.00 ft / 5.18 m
   Ends:   Unarmoured
     Main Belt covers 101 % of normal length

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   12.0" / 305 mm   7.00" / 178 mm      11.0" / 279 mm
   2nd:   12.0" / 305 mm   7.00" / 178 mm      11.0" / 279 mm
   3rd:   1.00" / 25 mm         -               -

  - Armour deck: 2.00" / 51 mm, Conning tower: 3.00" / 76 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 3 shafts, 62,892 shp / 46,918 Kw = 26.00 kts
   Range 8,000nm at 12.00 kts
   Bunker at max displacement = 2,396 tons

Complement:
   915 - 1,190

Cost:
   £4.000 million / $16.000 million

Distribution of weights at normal displacement:
   Armament: 1,157 tons, 5.2 %
   Armour: 7,221 tons, 32.2 %
      - Belts: 3,559 tons, 15.9 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 2,273 tons, 10.1 %
      - Armour Deck: 1,338 tons, 6.0 %
      - Conning Tower: 51 tons, 0.2 %
   Machinery: 2,343 tons, 10.5 %
   Hull, fittings & equipment: 8,967 tons, 40.0 %
   Fuel, ammunition & stores: 2,410 tons, 10.8 %
   Miscellaneous weights: 312 tons, 1.4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     27,563 lbs / 12,502 Kg = 31.9 x 12.0 " / 305 mm shells or 3.1 torpedoes
   Stability (Unstable if below 1.00): 1.06
   Metacentric height 4.4 ft / 1.3 m
   Roll period: 17.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 53 %
         - Recoil effect (Restricted arc if above 1.00): 0.74
   Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
   Hull has low quarterdeck
   Block coefficient: 0.532
   Length to Beam Ratio: 7.29 : 1
   'Natural speed' for length: 24.90 kts
   Power going to wave formation at top speed: 50 %
   Trim (Max stability = 0, Max steadiness = 100): 49
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 1.99 ft / 0.61 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      22.00 ft / 6.71 m
      - Forecastle (20 %):   19.00 ft / 5.79 m
      - Mid (50 %):      17.00 ft / 5.18 m
      - Quarterdeck (15 %):   12.00 ft / 3.66 m (17.00 ft / 5.18 m before break)
      - Stern:      12.00 ft / 3.66 m
      - Average freeboard:   17.19 ft / 5.24 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 75.1 %
      - Above water (accommodation/working, high = better): 115.9 %
   Waterplane Area: 36,150 Square feet or 3,358 Square metres
   Displacement factor (Displacement / loading): 104 %
   Structure weight / hull surface area: 175 lbs/sq ft or 853 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.96
      - Longitudinal: 1.42
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is adequate

Main Belt is Sloped 20 Degrees (External) - So the vertical length of such a belt is 16 feet - the main belt is really 12.7" thick H.

[Guinness]

That's a long main belt.

SS2 won't put guns forward of the forcastle percentage line, nor aft of the start of the quarterdeck. Since you have 20% and 15% respectively for those values, it means that your armament must be situated in the remaining 409.5 feet of hull. So a good rule of thumb is you probably want the main belt to be just a bit longer than that 409.5 feet. Or at least, that's how I sometimes do it.

[Logi]

I did it so:

The main guns added together take 200' with 5' spaces.

The super structure with secondary batteries and torpedo tubes is roughly 190'.

17' more belt to compensate for spaces that might be too small.