Arquese Class Crusiers

[snip]

Six Ships:
IRS Arquese
IRS Carantonus
IRS Tiberim
IRS Irminio (Sunk August 1914)
IRS Mancunio
IRS Royan

Arquese, Imperial Roman Cruiser laid down 1913

Displacement:
   2,990 t light; 3,116 t standard; 3,319 t normal; 3,481 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (400.26 ft / 393.70 ft) x 39.37 ft x (13.12 / 13.64 ft)
   (122.00 m / 120.00 m) x 12.00 m  x (4.00 / 4.16 m)

Armament:
      6 - 5.51" / 140 mm 55.0 cal guns - 85.98lbs / 39.00kg shells, 175 per gun
     Quick firing guns in deck and hoist mounts, 1909 Model
     2 x Twin mounts on centreline ends, evenly spread
     2 x Single mounts on sides, forward deck aft
      4 - 2.95" / 75.0 mm 45.0 cal guns - 13.23lbs / 6.00kg shells, 250 per gun
     Quick firing guns in deck and hoist mounts, 1902 Model
     4 x Single mounts on sides, evenly spread
      4 raised mounts
      2 - 1.77" / 45.0 mm 50.0 cal guns - 2.76lbs / 1.25kg shells, 550 per gun
     Anti-air guns in deck mounts, 1913 Model
     2 x Single mounts on sides, forward deck aft
      2 raised mounts
      4 - 0.26" / 6.5 mm 110.0 cal guns - 0.01lbs / 0.00kg shells, 3,000 per gun
     Machine guns in deck mounts, 1913 Model
     4 x Single mounts on sides, evenly spread
      4 raised mounts
      Weight of broadside 574 lbs / 261 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.36" / 60 mm   285.43 ft / 87.00 m   9.84 ft / 3.00 m
   Ends:   0.79" / 20 mm   108.23 ft / 32.99 m   9.84 ft / 3.00 m
     Main Belt covers 112 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.98" / 25 mm   0.20" / 5 mm      1.97" / 50 mm
   2nd:   0.39" / 10 mm   0.20" / 5 mm            -
   3rd:   0.20" / 5 mm         -               -

   - Protected deck - single deck:
   For and Aft decks: 1.57" / 40 mm
   Forecastle: 0.79" / 20 mm  Quarter deck: 0.79" / 20 mm

   - Conning towers: Forward 1.97" / 50 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 22,000 shp / 16,412 Kw = 25.84 kts
   Range 5,000nm at 10.00 kts
   Bunker at max displacement = 365 tons

Complement:
   218 - 284

Cost:
   £0.320 million / $1.282 million

Distribution of weights at normal displacement:
   Armament: 177 tons, 5.3 %
      - Guns: 177 tons, 5.3 %
   Armour: 628 tons, 18.9 %
      - Belts: 299 tons, 9.0 %
      - Armament: 16 tons, 0.5 %
      - Armour Deck: 303 tons, 9.1 %
      - Conning Tower: 9 tons, 0.3 %
   Machinery: 861 tons, 25.9 %
   Hull, fittings & equipment: 995 tons, 30.0 %
   Fuel, ammunition & stores: 329 tons, 9.9 %
   Miscellaneous weights: 330 tons, 9.9 %
      - Hull below water: 220 tons
      - Hull above water: 25 tons
      - On freeboard deck: 75 tons
      - Above deck: 10 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     3,099 lbs / 1,406 Kg = 37.0 x 5.5 " / 140 mm shells or 0.8 torpedoes
   Stability (Unstable if below 1.00): 1.23
   Metacentric height 1.8 ft / 0.5 m
   Roll period: 12.3 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.48
   Seaboat quality  (Average = 1.00): 1.12

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.571 / 0.576
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 19.84 kts
   Power going to wave formation at top speed: 57 %
   Trim (Max stability = 0, Max steadiness = 100): 45
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 0.89 ft / 0.27 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   17.50 %,  15.58 ft / 4.75 m,  13.94 ft / 4.25 m
      - Forward deck:   40.00 %,  13.94 ft / 4.25 m,  13.94 ft / 4.25 m
      - Aft deck:   32.50 %,  13.94 ft / 4.25 m,  13.94 ft / 4.25 m
      - Quarter deck:   10.00 %,  13.94 ft / 4.25 m,  13.94 ft / 4.25 m
      - Average freeboard:      14.06 ft / 4.29 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 111.4 %
      - Above water (accommodation/working, high = better): 134.4 %
   Waterplane Area: 11,033 Square feet or 1,025 Square metres
   Displacement factor (Displacement / loading): 100 %
   Structure weight / hull surface area: 60 lbs/sq ft or 294 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.86
      - Longitudinal: 1.30
      - Overall: 0.90
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Misc Distribution
--Below Water (220t)
----216t Electric Drives
----4t Additional Pumps
--Above Water (25t)
----15t Improved Crew Accommodations
----10t Improved Officer Accommodations
--On Deck (75t)
----18t 1912 Fire Control
----18t 6x530mm Torpedoes [One triple tube mount per side]
----25t Long Range Wireless
----10t Short Range Wireless
----4t Construction Reserve
--Above Deck (10t)
----5t Improved Acquisition Structures
----5t Additional Searchlights

[snip]

By the end of 1923H1, the five surviving ships had been updated to 1918 Fire Control.