Super-Inflated, Super-Fast Battlecruiser using Springsharp

I decided to see what it would take to drive a large, fast battlecruiser at 40 knots. One nice thing is that there is enough leeway to have a good armament and improved armor. To do it, it takes extreme dimension and displacement inflation:

GB/CB/alt 8-shaft Super Fast, Great Britain Battlecruiser laid down 1923

Displacement:
	68,043 t light; 70,794 t standard; 74,376 t normal; 77,242 t full load

Dimensions: Length overall / water x beam x draught
	1,059.73 ft / 1,050.00 ft x 135.00 ft x 38.50 ft (normal load)
	323.00 m / 320.04 m x 41.15 m  x 11.73 m

Armament:
      9 - 17.00" / 432 mm guns (3x3 guns), 2,456.50lbs / 1,114.25kg shells, 1923 Model
	  Breech loading guns in turrets (on barbettes)
	  on centreline, evenly spread, 2 raised mounts
	  Aft Main mounts separated by engine room
      16 - 4.00" / 102 mm guns (8x2 guns), 32.00lbs / 14.51kg shells, 1923 Model
	  Quick firing guns in deck mounts 
	  on side, evenly spread, all raised mounts
	Weight of broadside 22,621 lbs / 10,260 kg
	Shells per gun, main battery: 100

Armour:
   - Belts:		Width (max)	Length (avg)		Height (avg)
	Main:	9.00" / 229 mm	675.00 ft / 205.74 m	16.00 ft / 4.88 m
	Ends:	Unarmoured
	  Main Belt covers 99 % of normal length
	  Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead:
		1.50" / 38 mm	675.00 ft / 205.74 m	29.00 ft / 8.84 m

   - Gun armour:	Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
	Main:	12.0" / 305 mm	9.00" / 229 mm		10.0" / 254 mm
	2nd:	1.00" / 25 mm	      -			      -

   - Armour deck: 3.00" / 76 mm

Machinery:
	Oil fired boilers, steam turbines, 
	Geared drive, 8 shafts, 493,970 shp / 368,501 Kw = 40.00 kts
	Range 7,500nm at 15.00 kts
	Bunker at max displacement = 6,447 tons

Complement:
	2,251 - 2,927

Cost:
	£20.562 million / $82.246 million

Distribution of weights at normal displacement:
	Armament: 2,828 tons, 3.8 %
	Armour: 14,597 tons, 19.6 %
	   - Belts: 4,141 tons, 5.6 %
	   - Torpedo bulkhead: 1,086 tons, 1.5 %
	   - Armament: 4,032 tons, 5.4 %
	   - Armour Deck: 5,337 tons, 7.2 %
	   - Conning Tower: 0 tons, 0.0 %
	Machinery: 16,510 tons, 22.2 %
	Hull, fittings & equipment: 34,109 tons, 45.9 %
	Fuel, ammunition & stores: 6,333 tons, 8.5 %
	Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  85,738 lbs / 38,890 Kg = 34.9 x 17.0 " / 432 mm shells or 9.4 torpedoes
	Stability (Unstable if below 1.00): 1.06
	Metacentric height 8.8 ft / 2.7 m
	Roll period: 19.1 seconds
	Steadiness	- As gun platform (Average = 50 %): 72 %
			- Recoil effect (Restricted arc if above 1.00): 0.62
	Seaboat quality  (Average = 1.00): 1.13

Hull form characteristics:
	Hull has a flush deck
	  and transom stern
	Block coefficient: 0.477
	Length to Beam Ratio: 7.78 : 1
	'Natural speed' for length: 37.87 kts
	Power going to wave formation at top speed: 57 %
	Trim (Max stability = 0, Max steadiness = 100): 64
	Bow angle (Positive = bow angles forward): 4.00 degrees
	Stern overhang: 7.00 ft / 2.13 m
	Freeboard (% = measuring location as a percentage of overall length):
	   - Stem:		39.00 ft / 11.89 m
	   - Forecastle (33 %):	37.00 ft / 11.28 m
	   - Mid (0 %):		35.00 ft / 10.67 m
	   - Quarterdeck (20 %):	35.00 ft / 10.67 m
	   - Stern:		37.00 ft / 11.28 m
	   - Average freeboard:	35.79 ft / 10.91 m

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 118.2 %
		- Above water (accommodation/working, high = better): 279.1 %
	Waterplane Area: 96,162 Square feet or 8,934 Square metres
	Displacement factor (Displacement / loading): 106 %
	Structure weight / hull surface area: 248 lbs/sq ft or 1,212 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 0.96
		- Longitudinal: 1.55
		- Overall: 1.00
	Hull space for machinery, storage, compartmentation is cramped
	Room for accommodation and workspaces is excellent
	Ship has slow, easy roll, a good, steady gun platform