Seaplane Operations Ship - 1921 Class

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Two Ships, names Soon(tm)

SOS-1921, Imperial Roman Republic Seaplane Operation Ship laid down 1921

Displacement:
   3,400 t light; 3,525 t standard; 4,013 t normal; 4,403 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (380.59 ft / 374.02 ft) x 45.93 ft x (16.40 / 17.60 ft)
   (116.00 m / 114.00 m) x 14.00 m  x (5.00 / 5.36 m)

Armament:
      4 - 5.51" / 140 mm 45.0 cal guns - 85.98lbs / 39.00kg shells, 200 per gun
     Quick firing guns in deck and hoist mounts, 1909 Model
     2 x Twin mounts on centreline, forward deck forward
      1 raised mount - superfiring
      1 - 3.94" / 100 mm 45.0 cal gun - 30.86lbs / 14.00kg shells, 350 per gun
     Anti-air gun in deck and hoist mount, 1915 Model
     1 x Single mount on centreline, forward deck aft
      1 raised mount
      4 - 0.26" / 6.5 mm 110.0 cal guns - 0.01lbs / 0.00kg shells, 15,000 per gun
     Machine guns in deck mounts, 1911 Model
     4 x Single mounts on sides, evenly spread
      4 raised mounts
      Weight of broadside 375 lbs / 170 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.57" / 40 mm   0.39" / 10 mm      1.57" / 40 mm
   2nd:   0.59" / 15 mm         -         0.98" / 25 mm
   3rd:   0.20" / 5 mm         -               -

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

   - Conning towers: Forward 2.95" / 75 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 20,000 shp / 14,920 Kw = 24.43 kts
   Range 7,000nm at 14.00 kts
   Bunker at max displacement = 879 tons

Complement:
   251 - 327

Cost:
   £0.638 million / $2.551 million

Distribution of weights at normal displacement:
   Armament: 81 tons, 2.0 %
      - Guns: 81 tons, 2.0 %
   Armour: 365 tons, 9.1 %
      - Armament: 13 tons, 0.3 %
      - Armour Deck: 336 tons, 8.4 %
      - Conning Tower: 16 tons, 0.4 %
   Machinery: 689 tons, 17.2 %
   Hull, fittings & equipment: 1,331 tons, 33.2 %
   Fuel, ammunition & stores: 613 tons, 15.3 %
   Miscellaneous weights: 935 tons, 23.3 %
      - Hull below water: 225 tons
      - Hull above water: 225 tons
      - On freeboard deck: 465 tons
      - Above deck: 20 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,561 lbs / 2,976 Kg = 78.4 x 5.5 " / 140 mm shells or 1.4 torpedoes
   Stability (Unstable if below 1.00): 1.22
   Metacentric height 2.2 ft / 0.7 m
   Roll period: 12.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.23
   Seaboat quality  (Average = 1.00): 1.43

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a round stern
   Block coefficient (normal/deep): 0.498 / 0.510
   Length to Beam Ratio: 8.14 : 1
   'Natural speed' for length: 19.34 kts
   Power going to wave formation at top speed: 56 %
   Trim (Max stability = 0, Max steadiness = 100): 35
   Bow angle (Positive = bow angles forward): 8.00 degrees
   Stern overhang: 3.58 ft / 1.09 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  21.33 ft / 6.50 m,  21.33 ft / 6.50 m
      - Forward deck:   25.00 %,  21.33 ft / 6.50 m,  21.33 ft / 6.50 m
      - Aft deck:   40.00 %,  12.30 ft / 3.75 m,  12.30 ft / 3.75 m
      - Quarter deck:   15.00 %,  12.30 ft / 3.75 m,  12.30 ft / 3.75 m
      - Average freeboard:      16.36 ft / 4.99 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 77.1 %
      - Above water (accommodation/working, high = better): 136.8 %
   Waterplane Area: 11,428 Square feet or 1,062 Square metres
   Displacement factor (Displacement / loading): 133 %
   Structure weight / hull surface area: 71 lbs/sq ft or 344 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.91
      - Longitudinal: 2.34
      - Overall: 1.00
   Excellent machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Good seaboat, rides out heavy weather easily

Misc Weight Distrubution
-Below Water (225t)
--175t Electric Drive
--25t Additional Damage Control Equipment
--25t AVGAS Safety Equipment
-Above Water (225t)
--100t Additional Support Equpment for Seaplanes and crew
--25t LR Wireless
--25t Improved Officer Accommodations
--25t Improved Crew Accommodations
--25t Additional Damage Control Equipment
--25t Enhanced Ventilation and Crew Comfort
-On Deck (465t)
--440t 4x Multi-Engine Seaplanes
--11t Fire Control
--10t SR Wireless
--4t Construction Reserve
-Above Deck (20t)
--15t Improved Signaling Equipment
--5t Night Fighting Equipment