(1888) Duquesne Class - LB

-- Overview --

Class of three ships Duquesne, Charlemange, and Napoleon. Lain down January 1888, and completed July 1889. Featured new 33cm/35 caliber guns.

-- Design --

Duquesne Class, Celtica BB laid down 1888

Displacement:

   9,328 t light; 9,814 t standard; 10,710 t normal; 11,427 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)

   (350.00 ft / 350.00 ft) x 70.00 ft x (25.50 / 26.90 ft)

   (106.68 m / 106.68 m) x 21.34 m  x (7.77 / 8.20 m)

Armament:

     4 - 12.99" / 330 mm 35.0 cal guns - 1,100.00lbs / 498.95kg shells, 60 per gun

     Breech loading guns in turret on barbette mounts, 1887 Model

     2 x 2-gun mounts on centreline ends, evenly spread

     12 - 5.91" / 150 mm 40.0 cal guns - 89.99lbs / 40.82kg shells, 150 per gun

     Quick firing guns in casemate mounts, 1888 Model

     12 x Single mounts on sides, aft deck forward

     12 - 3.54" / 90.0 mm 40.0 cal guns - 20.00lbs / 9.07kg shells, 250 per gun

     Quick firing guns in deck mounts, 1888 Model

     12 x Single mounts on sides, evenly spread

       12 raised mounts

     4 - 1.57" / 40.0 mm 40.0 cal guns - 2.01lbs / 0.91kg shells, 400 per gun

     Quick firing guns in deck mounts, 1888 Model

     4 x Single mounts on sides, evenly spread

       4 raised mounts

     Weight of broadside 5,728 lbs / 2,598 kg

     Main Torpedoes

     4 - 17.7" / 450 mm, 9.84 ft / 3.00 m torpedoes - 0.227 t each, 0.910 t total

   submerged side tubes

Armour:

  - Belts:        Width (max)    Length (avg)        Height (avg)

   Main:    13.0" / 330 mm    227.50 ft / 69.34 m    9.50 ft / 2.90 m

   Ends:    5.00" / 127 mm    122.50 ft / 37.34 m    9.50 ft / 2.90 m

   Upper:    5.00" / 127 mm    175.00 ft / 53.34 m    7.50 ft / 2.29 m

     Main Belt covers 100 % of normal length

  - Torpedo Bulkhead - Strengthened structural bulkheads:

       1.00" / 25 mm    227.50 ft / 69.34 m    25.00 ft / 7.62 m

   Beam between torpedo bulkheads 63.00 ft / 19.20 m

  - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)

   Main:    13.0" / 330 mm    6.00" / 152 mm        13.0" / 330 mm

   2nd:    5.00" / 127 mm    1.00" / 25 mm        1.00" / 25 mm

   3rd:    1.00" / 25 mm          -                  -

  - Protected deck - multiple decks:

   For and Aft decks: 2.04" / 52 mm

   Forecastle: 1.04" / 26 mm  Quarter deck: 1.04" / 26 mm

  - Conning towers: Forward 13.00" / 330 mm, Aft 0.00" / 0 mm

Machinery:

   Coal fired boilers, simple reciprocating steam engines,

   Direct drive, 2 shafts, 10,006 ihp / 7,464 Kw = 17.00 kts

   Range 4,952nm at 10.00 kts

   Bunker at max displacement = 1,613 tons (100% coal)

Complement:

   526 - 684

Cost:

   £0.950 million / $3.802 million

Distribution of weights at normal displacement:

   Armament: 888 tons, 8.3 %

      - Guns: 886 tons, 8.3 %

      - Weapons: 2 tons, 0.0 %

   Armour: 3,597 tons, 33.6 %

      - Belts: 1,815 tons, 16.9 %

      - Torpedo bulkhead: 210 tons, 2.0 %

      - Armament: 818 tons, 7.6 %

      - Armour Deck: 618 tons, 5.8 %

      - Conning Tower: 136 tons, 1.3 %

   Machinery: 1,943 tons, 18.1 %

   Hull, fittings & equipment: 2,901 tons, 27.1 %

   Fuel, ammunition & stores: 1,382 tons, 12.9 %

   Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:

   Survivability (Non-critical penetrating hits needed to sink ship):

     10,077 lbs / 4,571 Kg = 9.5 x 13.0 " / 330 mm shells or 11.7 torpedoes

   Stability (Unstable if below 1.00): 1.39

   Metacentric height 5.2 ft / 1.6 m

   Roll period: 12.8 seconds

   Steadiness    - As gun platform (Average = 50 %): 55 %

           - Recoil effect (Restricted arc if above 1.00): 0.32

   Seaboat quality  (Average = 1.00): 1.10

Hull form characteristics:

   Hull has rise forward of midbreak,

     a normal bow and a cruiser stern

   Block coefficient (normal/deep): 0.600 / 0.607

   Length to Beam Ratio: 5.00 : 1

   'Natural speed' for length: 18.71 kts

   Power going to wave formation at top speed: 50 %

   Trim (Max stability = 0, Max steadiness = 100): 50

   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:    18.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m

      - Forward deck:    22.00 %,  15.00 ft / 4.57 m,  15.00 ft / 4.57 m

      - Aft deck:    43.00 %,  7.50 ft / 2.29 m,  7.50 ft / 2.29 m

      - Quarter deck:    17.00 %,  7.50 ft / 2.29 m,  7.50 ft / 2.29 m

      - Average freeboard:        10.50 ft / 3.20 m

   Ship tends to be wet forward

Ship space, strength and comments:

   Space    - Hull below water (magazines/engines, low = better): 99.7 %

       - Above water (accommodation/working, high = better): 65.1 %

   Waterplane Area: 17,919 Square feet or 1,665 Square metres

   Displacement factor (Displacement / loading): 99 %

   Structure weight / hull surface area: 145 lbs/sq ft or 710 Kg/sq metre

   Hull strength (Relative):

       - Cross-sectional: 0.92

       - Longitudinal: 2.12

       - Overall: 1.00

   Adequate machinery, storage, compartmentation space

   Cramped accommodation and workspace room

Armament:

33cm/35 model 1887

15cm/40 model 1888

9cm/40 model 1880

4cm/40 model 1880

45cm/3 model 1880

Armor:

Main belt extends 2' below waterline

1" protected deck & slopes plus 0.5" battery and upper decks