USS Seattle (8 Mk 42s)

USS Seattle, American Seattle-class anti-aircraft cruiser laid down 1947 (Engine 1948)

Displacement:
	16,025 t light; 16,983 t standard; 18,366 t normal; 19,473 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
	(704.25 ft / 679.13 ft) x 71.49 ft x (24.93 / 26.10 ft)
	(214.66 m / 207.00 m) x 21.79 m  x (7.60 / 7.95 m)

Armament:
      6 - 6.00" / 152 mm 47.0 cal guns - 130.00lbs / 58.97kg shells, 403 per gun
	  Dual purpose guns in turret on barbette mounts, 1947 Model
	  2 x 2-gun mounts on centreline, forward deck forward
		1 raised mount - superfiring
	  1 x 2-gun mount on centreline, forward deck centre
		1 double raised mount
      6 - 6.00" / 152 mm 47.0 cal guns - 130.01lbs / 58.97kg shells, 403 per gun
	  Dual purpose guns in turret on barbette mounts, 1947 Model
	  2 x 2-gun mounts on centreline, aft deck aft
		1 raised mount - superfiring
	  1 x 2-gun mount on centreline, aft deck centre
		1 double raised mount
      8 - 5.00" / 127 mm 54.0 cal guns - 70.00lbs / 31.75kg shells, 150 per gun
	  Dual purpose guns in turret on barbette mounts, 1947 Model
	  4 x Single mounts on sides, forward deck aft
		2 raised mounts - superfiring
	  4 x Single mounts on sides, aft deck forward
		2 raised mounts - superfiring
      16 - 3.00" / 76.2 mm 50.0 cal guns - 13.00lbs / 5.90kg shells, 1,500 per gun
	  Dual purpose guns in deck mounts, 1947 Model
	  4 x 2-gun mounts on sides, forward evenly spread
		2 raised mounts
	  4 x 2-gun mounts on sides, aft evenly spread
		2 raised mounts
      2 - 3.00" / 76.2 mm 50.0 cal guns - 13.01lbs / 5.90kg shells, 1,500 per gun
	  Dual purpose guns in deck mounts, 1947 Model
	  2 x Single mounts on sides, aft deck aft
      Weight of broadside 2,354 lbs / 1,068 kg

Armour:
   - Belts:		Width (max)	Length (avg)		Height (avg)
	Main:	5.00" / 127 mm	380.31 ft / 115.92 m	10.14 ft / 3.09 m
	Ends:	1.00" / 25 mm	298.79 ft / 91.07 m	10.14 ft / 3.09 m
	Upper:	5.00" / 127 mm	380.31 ft / 115.92 m	8.01 ft / 2.44 m
	  Main Belt covers 86 % of normal length

   - Torpedo Bulkhead - Additional damage containing bulkheads:
		3.00" / 76 mm	380.31 ft / 115.92 m	22.57 ft / 6.88 m
	Beam between torpedo bulkheads 64.47 ft / 19.65 m

   - Gun armour:	Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
	Main:	6.50" / 165 mm	3.25" / 83 mm		5.00" / 127 mm
	2nd:	6.50" / 165 mm	3.25" / 83 mm		5.00" / 127 mm
	3rd:	5.00" / 127 mm	2.25" / 57 mm		3.25" / 83 mm

   - Armoured deck - multiple decks:
	For and Aft decks: 3.50" / 89 mm
	Forecastle: 1.00" / 25 mm  Quarter deck: 1.00" / 25 mm

   - Conning towers: Forward 4.49" / 114 mm, Aft 4.49" / 114 mm

Machinery:
	Oil fired boilers, steam turbines,
	Geared drive, 4 shafts, 134,700 shp / 100,486 Kw = 33.02 kts
	Range 8,640nm at 15.00 kts
	Bunker at max displacement = 2,489 tons

Complement:
	788 - 1,025

Cost:
	£8.950 million / $35.799 million

Distribution of weights at normal displacement:
	Armament: 687 tons, 3.7 %
	   - Guns: 687 tons, 3.7 %
	Armour: 5,470 tons, 29.8 %
	   - Belts: 1,572 tons, 8.6 %
	   - Torpedo bulkhead: 953 tons, 5.2 %
	   - Armament: 1,047 tons, 5.7 %
	   - Armour Deck: 1,764 tons, 9.6 %
	   - Conning Towers: 135 tons, 0.7 %
	Machinery: 3,292 tons, 17.9 %
	Hull, fittings & equipment: 6,276 tons, 34.2 %
	Fuel, ammunition & stores: 2,341 tons, 12.7 %
	Miscellaneous weights: 300 tons, 1.6 %
	   - Hull above water: 150 tons
	   - Above deck: 150 tons

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  29,656 lbs / 13,452 Kg = 274.6 x 6.0 " / 152 mm shells or 4.5 torpedoes
	Stability (Unstable if below 1.00): 1.06
	Metacentric height 3.4 ft / 1.0 m
	Roll period: 16.3 seconds
	Steadiness	- As gun platform (Average = 50 %): 52 %
			- Recoil effect (Restricted arc if above 1.00): 0.45
	Seaboat quality  (Average = 1.00): 1.03

Hull form characteristics:
	Hull has low quarterdeck ,
	  an extended bulbous bow and a cruiser stern
	Block coefficient (normal/deep): 0.531 / 0.538
	Length to Beam Ratio: 9.50 : 1
	'Natural speed' for length: 26.06 kts
	Power going to wave formation at top speed: 56 %
	Trim (Max stability = 0, Max steadiness = 100): 50
	Bow angle (Positive = bow angles forward): 37.00 degrees
	Stern overhang: 4.00 ft / 1.22 m
	Freeboard (% = length of deck as a percentage of waterline length):
				Fore end,	 Aft end
	   - Forecastle:	22.00 %,  28.02 ft / 8.54 m,  24.93 ft / 7.60 m
	   - Forward deck:	28.00 %,  24.93 ft / 7.60 m,  24.93 ft / 7.60 m
	   - Aft deck:	28.00 %,  24.93 ft / 7.60 m,  24.93 ft / 7.60 m
	   - Quarter deck:	22.00 %,  10.01 ft / 3.05 m,  10.01 ft / 3.05 m
	   - Average freeboard:		21.92 ft / 6.68 m
	Ship tends to be wet forward

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 80.8 %
		- Above water (accommodation/working, high = better): 200.6 %
	Waterplane Area: 33,287 Square feet or 3,092 Square metres
	Displacement factor (Displacement / loading): 128 %
	Structure weight / hull surface area: 128 lbs/sq ft or 624 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 0.97
		- Longitudinal: 1.31
		- Overall: 1.00
	Excellent machinery, storage, compartmentation space
	Excellent accommodation and workspace room

Aviation facilities:
-Rotating compressed air catapult above hangar, just before the beginning of the quarterdeck.
-Hangar for 1-2 SC-1 Seahawk or Vought OS2U Kingfisher seaplanes, as well as 3-4 Sikorsky H-34 Choctaw helicopters. Hangar opens onto quarterdeck.
-Landing pad for helicopters on quarterdeck.
-Seaplane recovery crane mounted near catapult.