1921 MN Surcouf

Surcouf, France curiasse porte-avion sous-marin laid down 1915 (Engine 1921)

Displacement:
	46,434 t light; 47,837 t standard; 51,616 t normal; 54,639 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
	(731.63 ft / 731.63 ft) x 99.74 ft x (45.93 / 48.03 ft)
	(223.00 m / 223.00 m) x 30.40 m  x (14.00 / 14.64 m)

Armament:
      9 - 12.01" / 305 mm 45.0 cal guns - 952.40lbs / 432.00kg shells, 75 per gun
	  Breech loading guns in turret on barbette mounts, 1915 Model
	  3 x 3-gun mounts on centreline, forward evenly spread
      4 - 2.95" / 75.0 mm 50.0 cal guns - 13.07lbs / 5.93kg shells, 450 per gun
	  Anti-air guns in deck mounts, 1922 Model
	  2 x Single mounts on centreline, evenly spread
		2 raised mounts
	  2 x Single mounts on centreline, evenly spread
		2 double raised mounts
      Weight of broadside 8,624 lbs / 3,912 kg
      Main Torpedoes
      28 - 21.7" / 550 mm, 26.90 ft / 8.20 m torpedoes - 1.792 t each, 50.168 t total
	submerged bow & stern tubes
      2nd Torpedoes
      72 - 21.7" / 550 mm, 26.90 ft / 8.20 m torpedoes - 1.792 t each, 129.003 t total
	below water reloads

Armour:
   - Belts:		Width (max)	Length (avg)		Height (avg)
	Ends:	Unarmoured

   - Torpedo Bulkhead - Strengthened structural bulkheads:
		1.57" / 40 mm	427.56 ft / 130.32 m	45.93 ft / 14.00 m
	Beam between torpedo bulkheads 59.06 ft / 18.00 m

   - Gun armour:	Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
	Main:	3.54" / 90 mm	1.18" / 30 mm		1.18" / 30 mm

Machinery:
	Diesel Internal combustion generators plus batteries,
	Electric motors, 2 shafts, 73,384 shp / 54,744 Kw = 24.00 kts
	Range 10,000nm at 15.00 kts
	Bunker at max displacement = 6,803 tons

Complement:
	1,711 - 2,225

Cost:
	£3.950 million / $15.799 million

Distribution of weights at normal displacement:
	Armament: 1,990 tons, 3.9 %
	   - Guns: 1,728 tons, 3.3 %
	   - Weapons: 262 tons, 0.5 %
	Armour: 1,239 tons, 2.4 %
	   - Torpedo bulkhead: 1,144 tons, 2.2 %
	   - Armament: 95 tons, 0.2 %
	Machinery: 2,527 tons, 4.9 %
	Hull, fittings & equipment: 24,678 tons, 47.8 %
	Fuel, ammunition & stores: 5,182 tons, 10.0 %
	Miscellaneous weights: 16,000 tons, 31.0 %
	   - Hull below water: 13,000 tons
	   - On freeboard deck: 3,000 tons

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  54,100 lbs / 24,539 Kg = 62.5 x 12.0 " / 305 mm shells or 6.6 torpedoes
	Stability (Unstable if below 1.00): 1.47
	Metacentric height 9.7 ft / 2.9 m
	Roll period: 13.5 seconds
	Steadiness	- As gun platform (Average = 50 %): 4 %
			- Recoil effect (Restricted arc if above 1.00): 0.01
	Seaboat quality  (Average = 1.00): 0.01

Hull form characteristics:
	Hull has a flush deck,
	  a straight bulbous bow and a cruiser stern
	Block coefficient (normal/deep): 0.539 / 0.546
	Length to Beam Ratio: 7.34 : 1
	'Natural speed' for length: 27.05 kts
	Power going to wave formation at top speed: 43 %
	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:	21.29 %,  4.95 ft / 1.51 m,  0.79 ft / 0.24 m
	   - Forward deck:	26.42 %,  0.79 ft / 0.24 m,  0.79 ft / 0.24 m
	   - Aft deck:	32.02 %,  0.79 ft / 0.24 m,  0.79 ft / 0.24 m
	   - Quarter deck:	20.27 %,  0.79 ft / 0.24 m,  0.79 ft / 0.24 m
	   - Average freeboard:		1.14 ft / 0.35 m
	Ship tends to be wet forward

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 99.8 %
		- Above water (accommodation/working, high = better): 4.4 %
	Waterplane Area: 50,404 Square feet or 4,683 Square metres
	Displacement factor (Displacement / loading): 176 %
	Structure weight / hull surface area: 402 lbs/sq ft or 1,964 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 2.89
		- Longitudinal: 1.76
		- Overall: 2.00
	Adequate machinery, storage, compartmentation space
	Extremely poor accommodation and workspace room
	Ship has quick, lively roll, not a steady gun platform
	Caution: Lacks seaworthiness - very limited seakeeping ability

IGNORE WARNINGS - ship is a submarine
ship presented in awash neutral buoyancy state immediately prior to diving
Ballast tanks hold 13000t
Standard displacement when surfaced with ballast tanks empty is about 35,000 tons

305mm/45 Model 1910
75mm/50 Model 1922
55cm 19D (1919)

13000 tons dive tanks when full
2400 tons aviation facilities (16 aircraft)
600 tons floatplane facilities (12 aircraft) - floatplanes can take off and recover from an awash deck directly

Operational depth: 200'
Emergency depth: 320' (160%)
Crush depth: 500' (250%)

Crew: 900 (50%)