Monitors

[KWorld]

Monitors of the USN

[KWorld]

USS Mohawk, United States Monitor laid down 1899

USS Mohawk completed H2, 1900
USS Navajo completed H2, 1900
USS Cherokee completed H2, 1900
USS Klingit completed H2, 1900
USS Seminole completed H2, 1900
USS Powhatan completed H2, 1900

Displacement:
   2,676 t light; 2,852 t standard; 3,074 t normal; 3,251 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (255.00 ft / 255.00 ft) x 50.00 ft x (12.50 / 13.12 ft)
   (77.72 m / 77.72 m) x 15.24 m  x (3.81 / 4.00 m)

Armament:
      2 - 12.00" / 305 mm 40.0 cal guns - 828.07lbs / 375.60kg shells, 100 per gun
     Breech loading guns in turret on barbette mount, 1898 Model
     1 x Twin mount on centreline amidships (forward deck)
      4 - 4.00" / 102 mm 50.0 cal guns - 33.00lbs / 14.97kg shells, 250 per gun
     Quick firing guns in casemate mounts, 1898 Model
     4 x Single mounts on side ends, evenly spread
      4 - 2.24" / 57.0 mm 45.0 cal guns - 5.70lbs / 2.58kg shells, 300 per gun
     Quick firing guns in deck mounts, 1899 Model
     4 x Single mounts on sides, evenly spread
      4 raised mounts
      Weight of broadside 1,811 lbs / 821 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   8.00" / 203 mm   125.00 ft / 38.10 m   9.00 ft / 2.74 m
   Ends:   4.00" / 102 mm   130.00 ft / 39.62 m   9.00 ft / 2.74 m
     Main Belt covers 75 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   12.0" / 305 mm   8.00" / 203 mm      12.0" / 305 mm
   2nd:   2.00" / 51 mm         -               -
   3rd:   0.50" / 13 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 1.00" / 25 mm
   Forecastle: 1.00" / 25 mm  Quarter deck: 1.00" / 25 mm

   - Conning towers: Forward 12.00" / 305 mm, Aft 0.00" / 0 mm

Machinery:
   Coal fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 1,629 ihp / 1,215 Kw = 12.50 kts
   Range 3,000nm at 10.00 kts
   Bunker at max displacement = 400 tons (100% coal)

Complement:
   206 - 268

Cost:
   £0.276 million / $1.103 million

Distribution of weights at normal displacement:
   Armament: 293 tons, 9.5 %
      - Guns: 293 tons, 9.5 %
   Armour: 1,076 tons, 35.0 %
      - Belts: 621 tons, 20.2 %
      - Armament: 214 tons, 7.0 %
      - Armour Deck: 186 tons, 6.1 %
      - Conning Tower: 55 tons, 1.8 %
   Machinery: 259 tons, 8.4 %
   Hull, fittings & equipment: 1,048 tons, 34.1 %
   Fuel, ammunition & stores: 398 tons, 12.9 %
   Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     3,594 lbs / 1,630 Kg = 4.2 x 12.0 " / 305 mm shells or 1.4 torpedoes
   Stability (Unstable if below 1.00): 1.30
   Metacentric height 2.8 ft / 0.9 m
   Roll period: 12.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 60 %
         - Recoil effect (Restricted arc if above 1.00): 0.25
   Seaboat quality  (Average = 1.00): 0.84

Hull form characteristics:
   Hull has raised forecastle,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0.675 / 0.680
   Length to Beam Ratio: 5.10 : 1
   'Natural speed' for length: 15.97 kts
   Power going to wave formation at top speed: 41 %
   Trim (Max stability = 0, Max steadiness = 100): 71
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  10.00 ft / 3.05 m,  10.00 ft / 3.05 m
      - Forward deck:   30.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Aft deck:   35.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Quarter deck:   15.00 %,  5.00 ft / 1.52 m,  5.00 ft / 1.52 m
      - Average freeboard:      6.00 ft / 1.83 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 71.4 %
      - Above water (accommodation/working, high = better): 46.2 %
   Waterplane Area: 9,992 Square feet or 928 Square metres
   Displacement factor (Displacement / loading): 103 %
   Structure weight / hull surface area: 97 lbs/sq ft or 472 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.98
      - Longitudinal: 1.26
      - Overall: 1.01
   Excellent machinery, storage, compartmentation space
   Extremely poor accommodation and workspace room
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather