Amazon Ad

Wednesday, January 26, 2005

An unarmored cruiser (GB/CL/1927 Unarmored)

I thought that the other missing piece was an unarmored cruiser to go with the rest of my British cruiser family for 1927. The odd thing about this ship is that it is fast, like a destroyer (35 knots). Not having armor almost is a mandate for having speed. The armament is destroyer-like or A/A cruiser-like, being 10-5.1in DP guns with 24-40mm AA. I am interested in the 5.1in gun. The British almost adopted the caliber, and then backed off, as they were concerned about the shot weight. A cruiser should overcome that objection, as the ship is much more substantial. I also included 8-21in TT. The only negative is that due to the speed, the space below decks is cramped.
GB/CL/1927 Unarmored, Great Britain Unarmored Cruiser laid down 1927

Displacement:
	5,260 t light; 5,488 t standard; 6,244 t normal; 6,850 t full load

Dimensions: Length overall / water x beam x draught
	512.94 ft / 512.00 ft x 51.00 ft x 18.00 ft (normal load)
	156.35 m / 156.06 m x 15.54 m  x 5.49 m

Armament:
      10 - 5.10" / 130 mm guns (5x2 guns), 66.33lbs / 30.08kg shells, 1927 Model
	  Dual purpose guns in deck mounts with hoists
	  on centreline ends, majority forward, all raised mounts - superfiring
      24 - 1.57" / 40.0 mm guns (6x4 guns), 1.95lbs / 0.89kg shells, 1927 Model
	  Anti-aircraft guns in deck mounts 
	  on side ends, evenly spread, all raised mounts - superfiring
	Weight of broadside 710 lbs / 322 kg
	Shells per gun, main battery: 250
	8 - 21.0" / 533.4 mm above water torpedoes

Machinery:
	Oil fired boilers, steam turbines, 
	Geared drive, 4 shafts, 81,222 shp / 60,592 Kw = 35.00 kts
	Range 8,000nm at 15.00 kts
	Bunker at max displacement = 1,362 tons

Complement:
	350 - 456

Cost:
	£2.246 million / $8.983 million

Distribution of weights at normal displacement:
	Armament: 89 tons, 1.4 %
	Machinery: 2,564 tons, 41.1 %
	Hull, fittings & equipment: 2,608 tons, 41.8 %
	Fuel, ammunition & stores: 984 tons, 15.8 %
	Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  4,380 lbs / 1,987 Kg = 66.0 x 5.1 " / 130 mm shells or 0.8 torpedoes
	Stability (Unstable if below 1.00): 1.36
	Metacentric height 3.1 ft / 1.0 m
	Roll period: 12.1 seconds
	Steadiness	- As gun platform (Average = 50 %): 52 %
			- Recoil effect (Restricted arc if above 1.00): 0.33
	Seaboat quality  (Average = 1.00): 1.05

Hull form characteristics:
	Hull has a flush deck
	  and transom stern
	Block coefficient: 0.465
	Length to Beam Ratio: 10.04 : 1
	'Natural speed' for length: 25.92 kts
	Power going to wave formation at top speed: 63 %
	Trim (Max stability = 0, Max steadiness = 100): 50
	Bow angle (Positive = bow angles forward): 2.00 degrees
	Stern overhang: 0.00 ft / 0.00 m
	Freeboard (% = measuring location as a percentage of overall length):
	   - Stem:		27.00 ft / 8.23 m
	   - Forecastle (20 %):	19.00 ft / 5.79 m
	   - Mid (50 %):		19.00 ft / 5.79 m
	   - Quarterdeck (15 %):	19.00 ft / 5.79 m
	   - Stern:		19.00 ft / 5.79 m
	   - Average freeboard:	19.64 ft / 5.99 m

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 144.6 %
		- Above water (accommodation/working, high = better): 143.0 %
	Waterplane Area: 17,526 Square feet or 1,628 Square metres
	Displacement factor (Displacement / loading): 107 %
	Structure weight / hull surface area: 85 lbs/sq ft or 416 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 0.92
		- Longitudinal: 2.11
		- Overall: 1.00
	Hull space for machinery, storage, compartmentation is cramped
	Room for accommodation and workspaces is excellent

No comments:

Amazon Context Links