Rohan 1911 Battleship Designs

[Ithekro]

There are two versions of this design, based on the engine being different (1909 and 1912 versions)
(basically the Pennsylania types)

First there is the basic 1909 engine model that can be built as of January 1911.

Aldor

Rohan Battleship laid down 1911 (Engine 1909)

Displacement:
   27,759 t light; 29,369 t standard; 30,500 t normal; 31,282 t full load

Dimensions: Length overall / water x beam x draught
   595.00 ft / 590.00 ft x 108.00 ft x 27.00 ft (normal load)
   181.36 m / 179.83 m x 32.92 m  x 8.23 m

Armament:
      12 - 14.00" / 356 mm guns (4x3 guns), 1,372.00lbs / 622.33kg shells, 1911 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      12 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1911 Model
     Quick firing guns in casemate mounts
     on side, evenly spread
      8 - 1.50" / 38.1 mm guns in single mounts, 1.69lbs / 0.77kg shells, 1911 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
      8 - 0.75" / 19.1 mm guns in single mounts, 0.21lbs / 0.10kg shells, 1911 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 17,775 lbs / 8,063 kg
   Shells per gun, main battery: 100

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.0" / 330 mm   385.00 ft / 117.35 m   11.00 ft / 3.35 m
   Ends:   5.00" / 127 mm   205.00 ft / 62.48 m   8.00 ft / 2.44 m
   Upper:   7.00" / 178 mm   385.00 ft / 117.35 m   8.00 ft / 2.44 m
     Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
      1.50" / 38 mm   385.00 ft / 117.35 m   27.00 ft / 8.23 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   14.0" / 356 mm   7.00" / 178 mm      14.0" / 356 mm
   2nd:   5.00" / 127 mm         -               -

   - Armour deck: 3.00" / 76 mm, Conning tower: 13.00" / 330 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 36,000 shp / 26,856 Kw = 20.92 kts
   Range 5,750nm at 10.00 kts (Bunkerage = 2,035 tons)

Complement:
   1,153 - 1,500

Cost:
   £3.067 million / $12.268 million

Distribution of weights at normal displacement:
   Armament: 2,222 tons, 7.3 %
   Armour: 10,778 tons, 35.3 %
      - Belts: 3,720 tons, 12.2 %
      - Torpedo bulkhead: 577 tons, 1.9 %
      - Armament: 3,619 tons, 11.9 %
      - Armour Deck: 2,587 tons, 8.5 %
      - Conning Tower: 274 tons, 0.9 %
   Machinery: 1,636 tons, 5.4 %
   Hull, fittings & equipment: 12,873 tons, 42.2 %
   Fuel, ammunition & stores: 2,741 tons, 9.0 %
   Miscellaneous weights: 250 tons, 0.8 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     32,178 lbs / 14,596 Kg = 23.5 x 14.0 " / 356 mm shells or 5.0 torpedoes
   Stability (Unstable if below 1.00): 1.07
   Metacentric height 6.3 ft / 1.9 m
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.66
   Seaboat quality  (Average = 1.00): 1.34

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.620
   Length to Beam Ratio: 5.46 : 1
   'Natural speed' for length: 24.29 kts
   Power going to wave formation at top speed: 45 %
   Trim (Max stability = 0, Max steadiness = 100): 52
   Bow angle (Positive = bow angles forward): 9.46 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      30.00 ft / 9.14 m
      - Forecastle (20 %):   24.00 ft / 7.32 m
      - Mid (50 %):      24.00 ft / 7.32 m (15.00 ft / 4.57 m aft of break)
      - Quarterdeck (15 %):   15.00 ft / 4.57 m
      - Stern:      15.00 ft / 4.57 m
      - Average freeboard:   19.98 ft / 6.09 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 89.8 %
      - Above water (accommodation/working, high = better): 147.5 %
   Waterplane Area: 46,619 Square feet or 4,331 Square metres
   Displacement factor (Displacement / loading): 95 %
   Structure weight / hull surface area: 211 lbs/sq ft or 1,029 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.57
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily
--------------------------------------------------------------------------------------------------------

Then there is the 1912 engined model that might be able to be laid down in July 1911.

Samwise

Rohan Battleship laid down 1911 (Engine 1912)

Displacement:
   27,893 t light; 29,503 t standard; 30,500 t normal; 31,176 t full load

Dimensions: Length overall / water x beam x draught
   595.00 ft / 590.00 ft x 108.00 ft x 27.00 ft (normal load)
   181.36 m / 179.83 m x 32.92 m  x 8.23 m

Armament:
      12 - 14.00" / 356 mm guns (4x3 guns), 1,372.00lbs / 622.33kg shells, 1911 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      12 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1911 Model
     Quick firing guns in casemate mounts
     on side, evenly spread
      8 - 1.50" / 38.1 mm guns in single mounts, 1.69lbs / 0.77kg shells, 1911 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
      8 - 0.75" / 19.1 mm guns in single mounts, 0.21lbs / 0.10kg shells, 1911 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 17,775 lbs / 8,063 kg
   Shells per gun, main battery: 100

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.0" / 330 mm   385.00 ft / 117.35 m   11.00 ft / 3.35 m
   Ends:   4.00" / 102 mm   205.00 ft / 62.48 m   11.00 ft / 3.35 m
   Upper:   7.00" / 178 mm   385.00 ft / 117.35 m   11.00 ft / 3.35 m
     Main Belt covers 100 % of normal length

   - Torpedo Bulkhead:
      1.50" / 38 mm   385.00 ft / 117.35 m   27.00 ft / 8.23 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   14.0" / 356 mm   7.00" / 178 mm      14.0" / 356 mm
   2nd:   7.00" / 178 mm         -               -

   - Armour deck: 3.00" / 76 mm, Conning tower: 13.00" / 330 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 3 shafts, 36,000 shp / 26,856 Kw = 20.92 kts
   Range 5,750nm at 10.00 kts (Bunkerage = 1,795 tons)

Complement:
   1,153 - 1,500

Cost:
   £3.044 million / $12.174 million

Distribution of weights at normal displacement:
   Armament: 2,222 tons, 7.3 %
   Armour: 11,250 tons, 36.9 %
      - Belts: 4,109 tons, 13.5 %
      - Torpedo bulkhead: 577 tons, 1.9 %
      - Armament: 3,703 tons, 12.1 %
      - Armour Deck: 2,587 tons, 8.5 %
      - Conning Tower: 274 tons, 0.9 %
   Machinery: 1,435 tons, 4.7 %
   Hull, fittings & equipment: 12,735 tons, 41.8 %
   Fuel, ammunition & stores: 2,607 tons, 8.5 %
   Miscellaneous weights: 250 tons, 0.8 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     32,972 lbs / 14,956 Kg = 24.0 x 14.0 " / 356 mm shells or 5.2 torpedoes
   Stability (Unstable if below 1.00): 1.06
   Metacentric height 6.3 ft / 1.9 m
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.65
   Seaboat quality  (Average = 1.00): 1.35

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.620
   Length to Beam Ratio: 5.46 : 1
   'Natural speed' for length: 24.29 kts
   Power going to wave formation at top speed: 45 %
   Trim (Max stability = 0, Max steadiness = 100): 52
   Bow angle (Positive = bow angles forward): 9.46 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      30.00 ft / 9.14 m
      - Forecastle (20 %):   24.00 ft / 7.32 m
      - Mid (50 %):      24.00 ft / 7.32 m (15.00 ft / 4.57 m aft of break)
      - Quarterdeck (15 %):   15.00 ft / 4.57 m
      - Stern:      15.00 ft / 4.57 m
      - Average freeboard:   19.98 ft / 6.09 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 87.3 %
      - Above water (accommodation/working, high = better): 147.5 %
   Waterplane Area: 46,619 Square feet or 4,331 Square metres
   Displacement factor (Displacement / loading): 95 %
   Structure weight / hull surface area: 209 lbs/sq ft or 1,018 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.56
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

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

Conclusion:  The trade-offs are not all that great, plus the Samwise losses an inch of end armor and costs a little more.  Rohan will probably just build the 1911 battleships with 1909 engines.


Now the 1913 version (with FC planned into the design from the start thus with less extra tonnage), come out better with a larger engine and improved range at a slight tonnage increase and length.  (New Mexico/California types?)

Berold

Rohan Battleship laid down 1913 (Engine 1912)

Displacement:
   28,897 t light; 30,537 t standard; 32,000 t normal; 33,042 t full load

Dimensions: Length overall / water x beam x draught
   635.00 ft / 630.00 ft x 108.00 ft x 27.00 ft (normal load)
   193.55 m / 192.02 m x 32.92 m  x 8.23 m

Armament:
      12 - 14.00" / 356 mm guns (4x3 guns), 1,372.00lbs / 622.33kg shells, 1913 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      12 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1913 Model
     Quick firing guns in casemate mounts
     on side, evenly spread
      8 - 1.50" / 38.1 mm guns in single mounts, 1.69lbs / 0.77kg shells, 1913 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
      8 - 0.75" / 19.1 mm guns in single mounts, 0.21lbs / 0.10kg shells, 1913 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 17,775 lbs / 8,063 kg
   Shells per gun, main battery: 100

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.0" / 330 mm   385.00 ft / 117.35 m   11.00 ft / 3.35 m
   Ends:   5.00" / 127 mm   205.00 ft / 62.48 m   11.00 ft / 3.35 m
     40.00 ft / 12.19 m Unarmoured ends
   Upper:   7.00" / 178 mm   385.00 ft / 117.35 m   11.00 ft / 3.35 m
     Main Belt covers 94 % of normal length

   - Torpedo Bulkhead:
      1.50" / 38 mm   385.00 ft / 117.35 m   27.00 ft / 8.23 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   14.0" / 356 mm   7.00" / 178 mm      14.0" / 356 mm
   2nd:   7.00" / 178 mm         -               -

   - Armour deck: 3.00" / 76 mm, Conning tower: 13.00" / 330 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 40,000 shp / 29,840 Kw = 21.50 kts
   Range 5,750nm at 12.00 kts (Bunkerage = 2,633 tons)

Complement:
   1,196 - 1,555

Cost:
   £3.383 million / $13.532 million

Distribution of weights at normal displacement:
   Armament: 2,222 tons, 6.9 %
   Armour: 11,517 tons, 36.0 %
      - Belts: 4,223 tons, 13.2 %
      - Torpedo bulkhead: 577 tons, 1.8 %
      - Armament: 3,703 tons, 11.6 %
      - Armour Deck: 2,730 tons, 8.5 %
      - Conning Tower: 283 tons, 0.9 %
   Machinery: 1,595 tons, 5.0 %
   Hull, fittings & equipment: 13,464 tons, 42.1 %
   Fuel, ammunition & stores: 3,103 tons, 9.7 %
   Miscellaneous weights: 100 tons, 0.3 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     35,947 lbs / 16,305 Kg = 26.2 x 14.0 " / 356 mm shells or 5.7 torpedoes
   Stability (Unstable if below 1.00): 1.07
   Metacentric height 6.4 ft / 1.9 m
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.64
   Seaboat quality  (Average = 1.00): 1.30

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.610
   Length to Beam Ratio: 5.83 : 1
   'Natural speed' for length: 25.10 kts
   Power going to wave formation at top speed: 44 %
   Trim (Max stability = 0, Max steadiness = 100): 54
   Bow angle (Positive = bow angles forward): 9.46 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      30.00 ft / 9.14 m
      - Forecastle (20 %):   24.00 ft / 7.32 m
      - Mid (50 %):      24.00 ft / 7.32 m (15.00 ft / 4.57 m aft of break)
      - Quarterdeck (15 %):   15.00 ft / 4.57 m
      - Stern:      15.00 ft / 4.57 m
      - Average freeboard:   19.98 ft / 6.09 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 84.6 %
      - Above water (accommodation/working, high = better): 150.1 %
   Waterplane Area: 49,195 Square feet or 4,570 Square metres
   Displacement factor (Displacement / loading): 98 %
   Structure weight / hull surface area: 208 lbs/sq ft or 1,017 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.41
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

[The Rock Doctor]

Agreed, not much difference between designs, and they're both pretty sturdy.

[P3D]

IIRC you have to dedicate 250t for the FCS unless there's a change in the rules.

The turret sides are weak.

[Ithekro]

For the FC on the 1913 model, if so , it is a simple fix.  I'm assuming wireless as standard fittings and equipment by this point in time.

I could be wrong.  If that is the case then I'll have to redesign them for more extra tonnage.

The sides of the turrets are no weaker than any other Rohirrim designed turret.

[Korpen]

The turret sides are weak.

They are not, an avarage of 18cm for sides and roof is quite allot.

[Ithekro]

On a slightly unrelated note, Rohan will start research into the next type of gun technology in 1911 (assuming I have the funds and research spaces).  This research may lead to a larger gun type that should be able to penetrate any known armor at battle ranges.  This weapon will not be fitted to any Rohirrim Battleships or Battlecruisers until at least the 1917 deigns if not the 1915 designs.  With the increased abilities of Fire Control and heavily armored warships such as the French Superbe, the Brandenburg Kaiser Wilhelm II, The Confederate  Nuevo Leon, the Orange Natal, and the Baltic Sweden, along with the hugeness of the Maori Bardiche, the additional power of the 15.5 inch guns becomes needed.

While it might be argued that a superior 14 inch weapon may be all that is needed, the specialists and Isengard will look into the 15.5 inch weapon just to see what it will do.

15.5"/42 cal Mark I


     Caliber = 15.5 inch (39.4 cm)
     Shell weight = 1800 lbs (817 kg)
     Muzzle velocity = 2599 fps (792 m/s)

     Relative ballistic performance: 0.70

     Muzzle energy = 256.4 megajoules = 94497.8 foot-tons

     Relative muzzle energy: 0.79

     Barrel length: 42 calibers


     Elevation          Range        Time      Velocity   Fall Angle

       2.5 deg        5300 yards     6.9 sec   2114 fps     2.9 deg
       5.0 deg        9400 yards    13.2 sec   1816 fps     6.4 deg
       7.5 deg       12800 yards    19.2 sec   1614 fps    10.3 deg
      10.0 deg       15600 yards    24.9 sec   1476 fps    14.5 deg
      12.5 deg       18100 yards    30.3 sec   1381 fps    18.8 deg
      15.0 deg       20200 yards    35.5 sec   1317 fps    23.2 deg
      20.0 deg       23800 yards    45.5 sec   1250 fps    31.6 deg
      25.0 deg       26700 yards    54.8 sec   1235 fps    38.9 deg
      30.0 deg       29000 yards    63.7 sec   1249 fps    45.3 deg
      35.0 deg       30800 yards    72.2 sec   1280 fps    50.7 deg
      40.0 deg       31900 yards    80.2 sec   1319 fps    55.3 deg
      45.0 deg       32400 yards    87.8 sec   1361 fps    59.3 deg
      50.0 deg       32100 yards    94.9 sec   1402 fps    62.9 deg


          Armor Penetration - Vertical Belt Armor

               (Relative armor quality, 0.83)

               Maximum penetration: 34.70 inches


     Elevation          Range            Belt       Deck

       1.2 deg        2800 yards         30 in
       1.9 deg        4200 yards         28 in
       2.7 deg        5600 yards         26 in
       3.2 deg        6600 yards          ...        1 in
       3.5 deg        7200 yards         24 in
       4.6 deg        8800 yards         22 in
       5.9 deg       10700 yards         20 in
       6.1 deg       11000 yards          ...        2 in
       7.5 deg       12800 yards         18 in
       9.5 deg       15100 yards          ...        3 in
       9.6 deg       15200 yards         16 in
      12.3 deg       17900 yards         14 in
      14.1 deg       19500 yards          ...        4 in
      16.1 deg       21100 yards         12 in
      18.3 deg       22700 yards          ...        5 in
      21.8 deg       24900 yards          ...        6 in
      21.9 deg       25000 yards         10 in
      25.3 deg       26900 yards          ...        7 in
      29.0 deg       28600 yards          ...        8 in
      31.0 deg       29400 yards          8 in
      32.7 deg       30000 yards          ...        9 in
      36.7 deg       31200 yards          ...       10 in
      40.9 deg       32000 yards          ...       11 in
      44.9 deg       32400 yards          6 in
      45.3 deg       32400 yards          ...       12 in
      49.8 deg       32100 yards          ...       13 in


     Maximum range = 32400 yards at 45.8 deg elevation

[Korpen]

On a slightly unrelated note, Rohan will start research into the next type of gun technology in 1911 (assuming I have the funds and research spaces).  This research may lead to a larger gun type that should be able to penetrate any known armor at battle ranges.  This weapon will not be fitted to any Rohirrim Battleships or Battlecruisers until at least the 1917 deigns if not the 1915 designs.

15.5"/42 cal Mark I


     Caliber = 15.5 inch (39.4 cm)
     Shell weight = 1800 lbs (817 kg)
     Muzzle velocity = 2599 fps (792 m/s)

     Relative ballistic performance: 0.70

     Muzzle energy = 256.4 megajoules = 94497.8 foot-tons

     Relative muzzle energy: 0.79

     Barrel length: 42 calibers


     Elevation          Range        Time      Velocity   Fall Angle

       2.5 deg        5300 yards     6.9 sec   2114 fps     2.9 deg
       5.0 deg        9400 yards    13.2 sec   1816 fps     6.4 deg
       7.5 deg       12800 yards    19.2 sec   1614 fps    10.3 deg
      10.0 deg       15600 yards    24.9 sec   1476 fps    14.5 deg
      12.5 deg       18100 yards    30.3 sec   1381 fps    18.8 deg
      15.0 deg       20200 yards    35.5 sec   1317 fps    23.2 deg
      20.0 deg       23800 yards    45.5 sec   1250 fps    31.6 deg
      25.0 deg       26700 yards    54.8 sec   1235 fps    38.9 deg
      30.0 deg       29000 yards    63.7 sec   1249 fps    45.3 deg
      35.0 deg       30800 yards    72.2 sec   1280 fps    50.7 deg
      40.0 deg       31900 yards    80.2 sec   1319 fps    55.3 deg
      45.0 deg       32400 yards    87.8 sec   1361 fps    59.3 deg
      50.0 deg       32100 yards    94.9 sec   1402 fps    62.9 deg


          Armor Penetration - Vertical Belt Armor

               (Relative armor quality, 0.83)

               Maximum penetration: 34.70 inches


     Elevation          Range            Belt       Deck

       1.2 deg        2800 yards         30 in
       1.9 deg        4200 yards         28 in
       2.7 deg        5600 yards         26 in
       3.2 deg        6600 yards          ...        1 in
       3.5 deg        7200 yards         24 in
       4.6 deg        8800 yards         22 in
       5.9 deg       10700 yards         20 in
       6.1 deg       11000 yards          ...        2 in
       7.5 deg       12800 yards         18 in
       9.5 deg       15100 yards          ...        3 in
       9.6 deg       15200 yards         16 in
      12.3 deg       17900 yards         14 in
      14.1 deg       19500 yards          ...        4 in
      16.1 deg       21100 yards         12 in
      18.3 deg       22700 yards          ...        5 in
      21.8 deg       24900 yards          ...        6 in
      21.9 deg       25000 yards         10 in
      25.3 deg       26900 yards          ...        7 in
      29.0 deg       28600 yards          ...        8 in
      31.0 deg       29400 yards          8 in
      32.7 deg       30000 yards          ...        9 in
      36.7 deg       31200 yards          ...       10 in
      40.9 deg       32000 yards          ...       11 in
      44.9 deg       32400 yards          6 in
      45.3 deg       32400 yards          ...       12 in
      49.8 deg       32100 yards          ...       13 in


     Maximum range = 32400 yards at 45.8 deg elevation

With what kind of shell is that calculated?

[Ithekro]

Whatever BigGun uses normally.  I figure that is probably an AP shell, so our regular shells will do less than what is stated here.

[Korpen]

Whatever BigGun uses normally.  I figure that is probably an AP shell, so our regular shells will do less than what is stated here.

Ok, never used BigGun much, prefere NaB. I just player around with your numbers, and I get a difference of over 10cm depending on the type of APC shell used (at ~12 000).

Looking at the numbers i get the feeling BigGuns uses WW2 shells as a benchmark.

[Ithekro]

I used what BigGun seems to think is mid-range World War One shell (0.7) against facehard armor (shell cap intact) (0.83)

[P3D]

In NaAB use German original KC, WWI Class B armor. Now how to calculate penetration for an arbitrary gun bore and shell weight?

For APC, select the German L/3.2 APC.

Getting Ballistic Coefficient is tricky. BC scales linearly with gun bore, and linearly with mass if shell shape and caliber is kept intact (it is proportional to cross-sectional density). So how to do it?

First, scale up the projectile mass from 15" to 15.5". 1653.4 x (15.5/15)^3 = 1.824lbs.

1800/1824=0.9868.

Make sure there's some difference between total and shell body weight, I usually subtract one pound - otherwise the program will assume that the shell is not capped, and penetration drops by 1-3"!!

Now Ballistic Coefficient for the 15" shell is 10.640.
BC for a 1824lbs 15.5" shell is 15.5/15 x 10.640 = 10.994667.

Now correct for the different shell weight: BC = 10.994667 x 1800/1824 = 10.850

Muzzle velocity calculation, based on the available technology (gun length limited to 40 caliber for guns larger than 15"):

Muzzle Energy is

ME = 0.04 x 15.5^3 x 40 = 5958.2 million lb(mass) x ft^2 /s^2

muzzle velocity:
MV =  (5,958,200,000 x 2 / 1800 )^0.5 =  2573 fps.

I got the following penetration figures (belt/deck@range):
22.8/0.8@5000 yards
17.9/1.8@10k
14.0/2.6@15k
11.0/3.2@20K
9.5/4.5@25k

[Korpen]

Getting Ballistic Coefficient is tricky. BC scales linearly with gun bore, and linearly with mass if shell shape and caliber is kept intact (it is proportional to cross-sectional density). So how to do it?

The Mv also affects the BC, that is why the slower the shell, the higher the BC.

[Ithekro]

14" belt penetration at 15,000 yards is about what I was after anyway.  With estimated ranges only going out to 18,000 yards with the newer fire control, that should be fine against most vessels even with the currect armor models.  Might have trouble against heavy deck armor expect at extreme ranges.  A better shell might correct that later on.  Now with the actual 24,000 yard combat ranges in play by the time these guns get into service in numbers?  Then we are talking nice deck armor penetration up to 4 inches at least, and powerful enough shells to hurt older battleships and battlecruisers (and the very heavy armored cruisers) that use 9-10 inches of armor.

[P3D]

The Mv also affects the BC, that is why the slower the shell, the higher the BC.

No. It depends on sectional density and shell form only, and has no velocity dependence whatsoever. The velocity dependence is separated into another factor.

[Ithekro]

As for the 1911 Battleship, I'll just go with two with 1909 engines.  It will save the worry and leaves the better engines for an improved design in 1913.

As for the proposed 1915 design with the new guns...
(Question:  Are the belts too high?)

Thengel

Rohan Battleship laid down 1915 (Engine 1912)

Displacement:
   33,864 t light; 35,550 t standard; 37,250 t normal; 38,461 t full load

Displacement:
   33,844 t light; 35,502 t standard; 37,200 t normal; 38,409 t full load

Dimensions: Length overall / water x beam x draught
   645.00 ft / 640.00 ft x 108.00 ft x 27.00 ft (normal load)
   196.59 m / 195.07 m x 32.92 m  x 8.23 m

Armament:
     8 - 15.50" / 394 mm guns (4x2 guns), 1,800.00lbs / 816.47kg shells, 1915 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
     16 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1915 Model
     Quick firing guns in casemate mounts
     on side, evenly spread, 4 raised mounts
     12 - 1.50" / 38.1 mm guns in single mounts, 1.69lbs / 0.77kg shells, 1915 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread, all raised mounts
     12 - 0.75" / 19.1 mm guns in single mounts, 0.21lbs / 0.10kg shells, 1915 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 16,151 lbs / 7,326 kg
   Shells per gun, main battery: 100

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   14.5" / 368 mm   420.00 ft / 128.02 m   22.00 ft / 6.71 m
   Ends:   5.00" / 127 mm   220.00 ft / 67.06 m   11.00 ft / 3.35 m
   Upper:   7.00" / 178 mm   420.00 ft / 128.02 m   11.00 ft / 3.35 m
     Main Belt covers 101 % of normal length

  - Torpedo Bulkhead:
      1.50" / 38 mm   420.00 ft / 128.02 m   27.00 ft / 8.23 m

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   14.5" / 368 mm   8.00" / 203 mm      14.5" / 368 mm
   2nd:   7.00" / 178 mm   4.00" / 102 mm            -

  - Armour deck: 3.00" / 76 mm, Conning tower: 14.50" / 368 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 4 shafts, 44,000 shp / 32,824 Kw = 21.36 kts
   Range 6,000nm at 12.00 kts (Bunkerage = 3,056 tons)

Complement:
   1,339 - 1,741

Cost:
   £4.623 million / $18.490 million

Distribution of weights at normal displacement:
   Armament: 2,081 tons, 5.6 %
   Armour: 15,657 tons, 42.1 %
      - Belts: 7,824 tons, 21.0 %
      - Torpedo bulkhead: 629 tons, 1.7 %
      - Armament: 3,808 tons, 10.2 %
      - Armour Deck: 3,047 tons, 8.2 %
      - Conning Tower: 350 tons, 0.9 %
   Machinery: 1,754 tons, 4.7 %
   Hull, fittings & equipment: 14,052 tons, 37.8 %
   Fuel, ammunition & stores: 3,356 tons, 9.0 %
   Miscellaneous weights: 300 tons, 0.8 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     51,195 lbs / 23,221 Kg = 27.5 x 15.5 " / 394 mm shells or 8.1 torpedoes
   Stability (Unstable if below 1.00): 1.12
   Metacentric height 7.0 ft / 2.1 m
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.54
   Seaboat quality  (Average = 1.00): 1.42

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.698
   Length to Beam Ratio: 5.93 : 1
   'Natural speed' for length: 25.30 kts
   Power going to wave formation at top speed: 45 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 9.46 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      30.00 ft / 9.14 m
      - Forecastle (20 %):   26.00 ft / 7.92 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:   21.12 ft / 6.44 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 70.7 %
      - Above water (accommodation/working, high = better): 155.0 %
   Waterplane Area: 54,897 Square feet or 5,100 Square metres
   Displacement factor (Displacement / loading): 103 %
   Structure weight / hull surface area: 197 lbs/sq ft or 963 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1.00
      - Longitudinal: 1.40
      - Overall: 1.04
   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
   Good seaboat, rides out heavy weather easily


A cost increase from 1911 - 1913:  about 1,000 tons.

Cost increase from 1913 - 1915: about a 5,000 ton increase.

This means one of two things:  1) There will be a need for such an expansion.  or 2) A different (cheaper) design will be built instead, thus saving this design for 1917.

Four options:
1) A 6 gun ship armed with 15.5 inch guns.
2) An improved 12 gun 14 inch armed vessel.
3) A 15 gun 14 inch armed vessel.
4) A 8 gun ship armed with 15.5 inch guns in twins and triples (three turrets).

There will likely be a pause in Battlecrusier production after the sixth ship is built until 1917 or so when a fast 14 inch or 15.5 inch gunned battlecruiser will be desired.