Imperito Class Battleships

[snip]

The Imperito class introduces two key innovations to the Imperial Navy's battleships, VTE Engines and Quick-Firing secondaries. These improvements allow for her to possess the first truly modern armor layout of a Roman capital ship.

Ships in Class: Two
--IRS Imperito
--IRS Sublimis (Sunk July 1915)

Imperito, Imperial Roman Republic Battleship laid down 1897

Displacement:
   14,500 t light; 15,148 t standard; 16,042 t normal; 16,757 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (433.07 ft / 426.51 ft) x 78.74 ft x (26.25 / 27.23 ft)
   (132.00 m / 130.00 m) x 24.00 m  x (8.00 / 8.30 m)

Armament:
      4 - 13.39" / 340 mm 35.0 cal guns - 1,124.36lbs / 510.00kg shells, 70 per gun
     Breech loading guns in turret on barbette mounts, 1893 Model
     2 x Twin mounts on centreline ends, evenly spread
      4 - 8.27" / 210 mm 40.0 cal guns - 242.51lbs / 110.00kg shells, 100 per gun
     Breech loading guns in turret on barbette mounts, 1893 Model
     4 x Single mounts on sides, evenly spread
      10 - 5.51" / 140 mm 45.0 cal guns - 79.37lbs / 36.00kg shells, 175 per gun
     Quick firing guns in casemate mounts, 1897 Model
     10 x Single mounts on sides, evenly spread
      10 hull mounts in casemates- Limited use in heavy seas
      12 - 2.95" / 75.0 mm 45.0 cal guns - 12.98lbs / 5.89kg shells, 250 per gun
     Quick firing guns in deck mounts, 1897 Model
     12 x Single mounts on sides, evenly spread
      6 raised mounts
      Weight of broadside 6,417 lbs / 2,911 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   11.8" / 300 mm   247.38 ft / 75.40 m   18.04 ft / 5.50 m
   Ends:   4.72" / 120 mm   179.10 ft / 54.59 m   9.84 ft / 3.00 m
   Upper:   3.94" / 100 mm   247.38 ft / 75.40 m   9.02 ft / 2.75 m
     Main Belt covers 89 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   15.0" / 380 mm   9.84" / 250 mm      15.0" / 380 mm
   2nd:   5.91" / 150 mm   3.94" / 100 mm      5.91" / 150 mm
   3rd:   3.94" / 100 mm   0.98" / 25 mm      3.94" / 100 mm
   4th:   0.59" / 15 mm         -               -

   - Armoured deck - multiple decks:
   For and Aft decks: 2.36" / 60 mm
   Forecastle: 0.98" / 25 mm  Quarter deck: 0.98" / 25 mm

   - Conning towers: Forward 9.84" / 250 mm, Aft 0.00" / 0 mm

Machinery:
   Coal fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 15,000 ihp / 11,190 Kw = 18.05 kts
   Range 4,500nm at 10.00 kts
   Bunker at max displacement = 1,609 tons (100% coal)

Complement:
   712 - 926

Cost:
   £1.316 million / $5.265 million

Distribution of weights at normal displacement:
   Armament: 1,047 tons, 6.5 %
      - Guns: 1,047 tons, 6.5 %
   Armour: 5,908 tons, 36.8 %
      - Belts: 3,171 tons, 19.8 %
      - Armament: 1,644 tons, 10.3 %
      - Armour Deck: 958 tons, 6.0 %
      - Conning Tower: 135 tons, 0.8 %
   Machinery: 2,459 tons, 15.3 %
   Hull, fittings & equipment: 4,822 tons, 30.1 %
   Fuel, ammunition & stores: 1,542 tons, 9.6 %
   Miscellaneous weights: 265 tons, 1.7 %
      - Hull below water: 25 tons
      - Hull above water: 100 tons
      - On freeboard deck: 100 tons
      - Above deck: 40 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     22,097 lbs / 10,023 Kg = 18.4 x 13.4 " / 340 mm shells or 2.6 torpedoes
   Stability (Unstable if below 1.00): 1.33
   Metacentric height 5.8 ft / 1.8 m
   Roll period: 13.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.50
   Seaboat quality  (Average = 1.00): 1.63

Hull form characteristics:
   Hull has low quarterdeck ,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.637 / 0.641
   Length to Beam Ratio: 5.42 : 1
   'Natural speed' for length: 20.65 kts
   Power going to wave formation at top speed: 47 %
   Trim (Max stability = 0, Max steadiness = 100): 43
   Bow angle (Positive = bow angles forward): -10.00 degrees
   Stern overhang: -4.92 ft / -1.50 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  18.86 ft / 5.75 m,  18.86 ft / 5.75 m
      - Forward deck:   30.00 %,  18.86 ft / 5.75 m,  18.86 ft / 5.75 m
      - Aft deck:   28.00 %,  18.86 ft / 5.75 m,  18.86 ft / 5.75 m
      - Quarter deck:   22.00 %,  9.84 ft / 3.00 m,  9.84 ft / 3.00 m
      - Average freeboard:      16.88 ft / 5.15 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 77.5 %
      - Above water (accommodation/working, high = better): 128.3 %
   Waterplane Area: 25,421 Square feet or 2,362 Square metres
   Displacement factor (Displacement / loading): 103 %
   Structure weight / hull surface area: 148 lbs/sq ft or 724 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.92
      - Longitudinal: 2.25
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Misc Distribution
--Below Water (25t)
----18t 12x350mm Torpedo (35 Pattern B)
----2t Additional Torpedo handling equipment
----5t Additional Pumps
--Above Water (100t)
----30t Flag Facilities
----30t Additional Troop Accomodations
----20t Improved Officer Accommodations
----20t Improved Crew Accomodations
----10t Construction Reserve
--On Deck (100t)
----30t Flad Gacilties
----20t Admiraltiy Accommodations
----50t Construction Reserve
--Above Deck (40t)
----20t Improved Aquisition Structures
----10t Additional Searchlights
----10t Improved Signaling Equipment

[snip]

In 1914H1, both of these ships were refit to equip modern fire control.

IRS Sublimis was sunk in this configuration at the Battle of Grand Turk on July 5th 1914

Imperito, Imperial Roman Republic Battleship laid down 1897

Displacement:
   14,500 t light; 15,148 t standard; 16,042 t normal; 16,757 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (433.07 ft / 426.51 ft) x 78.74 ft x (26.25 / 27.23 ft)
   (132.00 m / 130.00 m) x 24.00 m  x (8.00 / 8.30 m)

Armament:
      4 - 13.39" / 340 mm 35.0 cal guns - 1,124.36lbs / 510.00kg shells, 70 per gun
     Breech loading guns in turret on barbette mounts, 1893 Model
     2 x Twin mounts on centreline ends, evenly spread
      4 - 8.27" / 210 mm 40.0 cal guns - 242.51lbs / 110.00kg shells, 100 per gun
     Breech loading guns in turret on barbette mounts, 1893 Model
     4 x Single mounts on sides, evenly spread
      10 - 5.51" / 140 mm 45.0 cal guns - 79.37lbs / 36.00kg shells, 175 per gun
     Quick firing guns in casemate mounts, 1897 Model
     10 x Single mounts on sides, evenly spread
      10 hull mounts in casemates- Limited use in heavy seas
      12 - 2.95" / 75.0 mm 45.0 cal guns - 12.98lbs / 5.89kg shells, 250 per gun
     Quick firing guns in deck mounts, 1897 Model
     12 x Single mounts on sides, evenly spread
      6 raised mounts
      Weight of broadside 6,417 lbs / 2,911 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   11.8" / 300 mm   247.38 ft / 75.40 m   18.04 ft / 5.50 m
   Ends:   4.72" / 120 mm   179.10 ft / 54.59 m   9.84 ft / 3.00 m
   Upper:   3.94" / 100 mm   247.38 ft / 75.40 m   9.02 ft / 2.75 m
     Main Belt covers 89 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   15.0" / 380 mm   9.84" / 250 mm      15.0" / 380 mm
   2nd:   5.91" / 150 mm   3.94" / 100 mm      5.91" / 150 mm
   3rd:   3.94" / 100 mm   0.98" / 25 mm      3.94" / 100 mm
   4th:   0.59" / 15 mm         -               -

   - Armoured deck - multiple decks:
   For and Aft decks: 2.36" / 60 mm
   Forecastle: 0.98" / 25 mm  Quarter deck: 0.98" / 25 mm

   - Conning towers: Forward 9.84" / 250 mm, Aft 0.00" / 0 mm

Machinery:
   Coal fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 15,000 ihp / 11,190 Kw = 18.05 kts
   Range 4,500nm at 10.00 kts
   Bunker at max displacement = 1,609 tons (100% coal)

Complement:
   712 - 926

Cost:
   £1.316 million / $5.265 million

Distribution of weights at normal displacement:
   Armament: 1,047 tons, 6.5 %
      - Guns: 1,047 tons, 6.5 %
   Armour: 5,908 tons, 36.8 %
      - Belts: 3,171 tons, 19.8 %
      - Armament: 1,644 tons, 10.3 %
      - Armour Deck: 958 tons, 6.0 %
      - Conning Tower: 135 tons, 0.8 %
   Machinery: 2,459 tons, 15.3 %
   Hull, fittings & equipment: 4,822 tons, 30.1 %
   Fuel, ammunition & stores: 1,542 tons, 9.6 %
   Miscellaneous weights: 265 tons, 1.7 %
      - Hull below water: 25 tons
      - Hull above water: 100 tons
      - On freeboard deck: 100 tons
      - Above deck: 40 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     22,097 lbs / 10,023 Kg = 18.4 x 13.4 " / 340 mm shells or 2.6 torpedoes
   Stability (Unstable if below 1.00): 1.33
   Metacentric height 5.8 ft / 1.8 m
   Roll period: 13.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.50
   Seaboat quality  (Average = 1.00): 1.63

Hull form characteristics:
   Hull has low quarterdeck ,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.637 / 0.641
   Length to Beam Ratio: 5.42 : 1
   'Natural speed' for length: 20.65 kts
   Power going to wave formation at top speed: 47 %
   Trim (Max stability = 0, Max steadiness = 100): 43
   Bow angle (Positive = bow angles forward): -10.00 degrees
   Stern overhang: -4.92 ft / -1.50 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  18.86 ft / 5.75 m,  18.86 ft / 5.75 m
      - Forward deck:   30.00 %,  18.86 ft / 5.75 m,  18.86 ft / 5.75 m
      - Aft deck:   28.00 %,  18.86 ft / 5.75 m,  18.86 ft / 5.75 m
      - Quarter deck:   22.00 %,  9.84 ft / 3.00 m,  9.84 ft / 3.00 m
      - Average freeboard:      16.88 ft / 5.15 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 77.5 %
      - Above water (accommodation/working, high = better): 128.3 %
   Waterplane Area: 25,421 Square feet or 2,362 Square metres
   Displacement factor (Displacement / loading): 103 %
   Structure weight / hull surface area: 148 lbs/sq ft or 724 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.92
      - Longitudinal: 2.25
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Misc Distribution
--Below Water (25t)
----18t 12x350mm Torpedo (35 Pattern B)
----2t Additional Torpedo handling equipment
----5t Additional Pumps
--Above Water (100t)
----30t Flag Facilities
----35t 1912 FC
----20t Improved Officer Accommodations
----20t Improved Crew Accomodations
----5t Construction Reserve
--On Deck (100t)
----30t Flag Facilities
----70t 1912 Fire Control
--Above Deck (40t)
----20t Improved Aquisition Structures
----10t Additional Searchlights
----10t Improved Signaling Equipment

[snip]

IRS Imperito was removed from the active fleet list effective 1JAN1926 to be preserved as a museum ship.