1937 HMS Invincible

Invincible, British Empire Predreadnought Battlecruiser laid down 1937

Displacement:
	33,399 t light; 35,000 t standard; 40,000 t normal; 44,000 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
	(825.72 ft / 820.00 ft) x 64.00 ft (Bulges 88.00 ft) x (31.40 / 34.84 ft)
	(251.68 m / 249.94 m) x 19.51 m (Bulges 26.82 m)  x (9.57 / 10.62 m)

Armament:
      4 - 16"/45 Mark II guns - 2,375 lbs / 1,077.28kg shells, 60 per gun
	  Breech loading guns in turret on barbette mounts, 1938 Model
	  1 x 2-gun mount on centreline, aft deck aft
	  1 x 2-gun mount on centreline, forward deck forward

      4 - 8"/50 Mark VIII guns - 256 lbs / 116.12kg shells, 150 per gun
	  Breech loading guns in turret on barbette mounts, 1923 Model
	  2 x 2-gun mounts on centreline, evenly spread
		2 raised mounts

      8 - 6"/50 BL Mark XXII guns - 100 lbs / 45.36kg shells, 150 per gun
	  Quick firing guns in casemate mounts, 1921 Model
	  8 x Single mounts on sides, evenly spread

      16 - 4"/45 QF Mark XVI guns - 35 lbs / 15.88kg shells, 400 per gun
	  Dual purpose guns in deck and hoist mounts, 1934 Model
	  8 x Twin mounts on sides, evenly spread

      48 - 40mm/39 - 2pdr QF Mark VIII guns - 2 lbs / 0.91kg shells, 1,500 per gun
	  Anti-air guns in deck mounts, 1923 Model
	  6 x 2 row octuple mounts on sides, evenly spread
		6 raised mounts

      Weight of broadside 11,980 lbs / 5,434 kg

      Main Torpedoes - 4 sets below-deck mounted side rotating tubes
      16 - 24.5" / 622 mm, 26.50 ft / 8.08 m torpedoes - 2.321 t each, 37.141 t total
      Reloads - 4 sets below-deck mounted reloads
      16 - 24.5" / 622 mm, 26.50 ft / 8.08 m torpedoes - 2.321 t each, 37.141 t total

Armour:
   - Belts:		Width (max)	Length (avg)		Height (avg)
	Main:	18.0" / 457 mm	430.00 ft / 131.06 m	8.00 ft / 2.44 m
	Lower:	6-18"/152-457mm 430.00 ft / 131.06 m	6.00 ft / 1.83 m (Main belt total 14ft / 4.27m)
	Ends:  10-18"/254-457mm	390.00 ft / 118.87 m	8.00 ft / 2.44 m
	  Main Belt covers 81 % of normal length

   - Torpedo Defense - Strengthened structural bulkhead, five void spaces, integral bulge
   - Inner Holding Bulkhead:
		1.50" / 38 mm	451.00 ft / 137.46 m	24.00 ft / 7.32 m
	Beam between torpedo bulkheads 52.00 ft / 15.85 m

   - Integral Bulges and additional bulkheads:
		1.50" / 38 mm	565.00 ft / 172.21 m	21.00 ft / 6.40 m

   - Gun armour:	Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
	Main:	18.0" / 457 mm	7.00" / 178 mm		14.0" / 356 mm - barbette 18" above armoured deck
	2nd:	14.0" / 356 mm	6.00" / 152 mm		8.00" / 203 mm
	3rd:	14.0" / 356 mm	2.00" / 51 mm		12.0" / 305 mm
	4th:	2.00" / 51 mm	1.00" / 25 mm		2.00" / 51 mm

   - Armoured deck - single deck covers entire length of ship:
	For and Aft decks: 6.00" / 152 mm
	Forecastle: 6.00" / 152 mm  Quarter deck: 6.00" / 152 mm

   - Conning towers: Forward 18.00" / 457 mm, Aft 0.00" / 0 mm

Machinery:
	Oil fired boilers, steam turbines,
	Geared drive, 4 shafts, 183,974 shp / 137,244 Kw = 33.00 kts
	Range 19,945nm at 14.00 kts
	Bunker at max displacement = 9,000 tons

Complement:
	1,413 - 1,838

Cost:
	£15.647 million / $62.589 million

Distribution of weights at normal displacement:
	Armament: 2,406 tons, 6.0 %
	   - Guns: 2,285 tons, 5.7 %
	   - Weapons: 121 tons, 0.3 %
	Armour: 14,011 tons, 35.0 %
	   - Belts: 5,486 tons, 13.7 %
	   - Torpedo bulkhead: 601 tons, 1.5 %
	   - Bulges: 659 tons, 1.6 %
	   - Armament: 2,262 tons, 5.7 %
	   - Armour Deck: 4,551 tons, 11.4 %
	   - Conning Tower: 454 tons, 1.1 %
	Machinery: 5,099 tons, 12.7 %
	Hull, fittings & equipment: 11,710 tons, 29.3 %
	Fuel, ammunition & stores: 6,474 tons, 16.2 %
	Miscellaneous weights: 300 tons, 0.8 %
	   - On freeboard deck: 250 tons
	   - Above deck: 50 tons

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  50,415 lbs / 22,868 Kg = 24.6 x 16.0 " / 406 mm shells or 4.0 torpedoes
	Stability (Unstable if below 1.00): 1.06
	Metacentric height 2.9 ft / 0.9 m
	Roll period: 21.8 seconds
	Steadiness	- As gun platform (Average = 50 %): 50 %
			- Recoil effect (Restricted arc if above 1.00): 0.62
	Seaboat quality  (Average = 1.00): 0.88

Hull form characteristics:
	Hull has a flush deck,
	  a normal bow and large transom stern
	Block coefficient (normal/deep): 0.618 / 0.613
	Length to Beam Ratio: 9.32 : 1
	'Natural speed' for length: 32.46 kts
	Power going to wave formation at top speed: 55 %
	Trim (Max stability = 0, Max steadiness = 100): 56
	Bow angle (Positive = bow angles forward): 10.00 degrees
	Stern overhang: -3.00 ft / -0.91 m
	Freeboard (% = length of deck as a percentage of waterline length):
				Fore end,	 Aft end
	   - Forecastle:	30.00 %,  32.45 ft / 9.89 m,  20.00 ft / 6.10 m
	   - Forward deck:	30.00 %,  20.00 ft / 6.10 m,  20.00 ft / 6.10 m
	   - Aft deck:	25.00 %,  20.00 ft / 6.10 m,  20.00 ft / 6.10 m
	   - Quarter deck:	15.00 %,  20.00 ft / 6.10 m,  21.00 ft / 6.40 m
	   - Average freeboard:		21.57 ft / 6.57 m

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 79.5 %
		- Above water (accommodation/working, high = better): 103.3 %
	Waterplane Area: 40,696 Square feet or 3,781 Square metres
	Displacement factor (Displacement / loading): 118 %
	Structure weight / hull surface area: 182 lbs/sq ft or 891 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 1.08
		- Longitudinal: 0.97
		- Overall: 1.00
	Excellent machinery, storage, compartmentation space
	Adequate accommodation and workspace room
	Poor seaboat, wet and uncomfortable, reduced performance in heavy weather


Scharnhorst does 13600nmi at 14
Dunk does 16400 at 17, or about 25000@14

1.00 seakeeping at 32kt