Alternate use for a destroyer hull

Started by The Rock Doctor, December 16, 2007, 01:37:47 PM

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The Rock Doctor



A notional idea - a modified destroyer hull to function as a courier/dispatch vessel between Gran Colombia and its outer territories.  A minor amount of cargo and passengers would be embarked.  A large set of doors is installed on the aft superstructure, starboard side to facilitate loading cargo - hence the lopside boat arrangements.

Note:  I see that the aft boat is missing from the top view...

The power plant is unusual in that half of the boilers are oil-sprayed coal-firing, and the other half are oil-firing.  In this respect, the type would be a testbed of new oil-firing boilers.  The bunkerage is technically 45% coal as a result . 

Dispatch, laid down 1910 (Engine 1912)

Displacement:
   748 t light; 775 t standard; 973 t normal; 1,132 t full load

Dimensions: Length overall / water x beam x draught
   278.95 ft / 275.59 ft x 26.90 ft x 11.48 ft (normal load)
   85.02 m / 84.00 m x 8.20 m  x 3.50 m

Armament:
      3 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1909 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, majority aft, 1 raised mount aft
      2 - 2.56" / 65.0 mm guns in single mounts, 8.38lbs / 3.80kg shells, 1909 Model
     Quick firing anti-airship guns in deck mounts with hoists
     on side, all amidships
      2 - 0.31" / 8.0 mm guns in single mounts, 0.02lbs / 0.01kg shells, 1909 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 57 lbs / 26 kg
   Shells per gun, main battery: 200
   2 - 18.0" / 457 mm above water torpedoes

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.98" / 25 mm         -         0.98" / 25 mm
   2nd:   0.98" / 25 mm         -         0.98" / 25 mm

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 12,000 shp / 8,952 Kw = 26.37 kts
   Range 6,000nm at 12.00 kts (Bunkerage = 357 tons)

Complement:
   86 - 113

Cost:
   £0.094 million / $0.377 million

Distribution of weights at normal displacement:
   Armament: 7 tons, 0.7 %
   Armour: 7 tons, 0.7 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 7 tons, 0.7 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 444 tons, 45.6 %
   Hull, fittings & equipment: 228 tons, 23.4 %
   Fuel, ammunition & stores: 225 tons, 23.1 %
   Miscellaneous weights: 62 tons, 6.4 %
   -24 t:  Accomodation for twelve passengers
   -20 t:  Cargo
   -10 t:  Wireless
   -6 t:  Weight reserve
   -2 t:  Torpedoes

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     296 lbs / 134 Kg = 22.0 x 3.0 " / 76 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.35
   Metacentric height 1.2 ft / 0.4 m
   Roll period: 10.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.18
   Seaboat quality  (Average = 1.00): 1.31

Hull form characteristics:
   Hull has rise forward of midbreak
   Block coefficient: 0.400
   Length to Beam Ratio: 10.24 : 1
   'Natural speed' for length: 16.60 kts
   Power going to wave formation at top speed: 60 %
   Trim (Max stability = 0, Max steadiness = 100): 54
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: -3.28 ft / -1.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19.03 ft / 5.80 m
      - Forecastle (20 %):   15.75 ft / 4.80 m
      - Mid (40 %):      15.75 ft / 4.80 m (7.87 ft / 2.40 m aft of break)
      - Quarterdeck (15 %):   7.87 ft / 2.40 m
      - Stern:      7.87 ft / 2.40 m
      - Average freeboard:   11.29 ft / 3.44 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 160.3 %
      - Above water (accommodation/working, high = better): 89.9 %
   Waterplane Area: 4,564 Square feet or 424 Square metres
   Displacement factor (Displacement / loading): 87 %
   Structure weight / hull surface area: 25 lbs/sq ft or 120 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.64
      - Overall: 0.57
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

Borys

NEDS - Not Enough Deck Space for all those guns and torpedos;
Bambi must DIE!