New GC ships for H2, 1906

[The Rock Doctor]

Nothing sexy here, folks. 

Some admirals were complaining that their cruisers and torpedo-boats were spending too much time doing boring stuff like customs patrols and ship inspections.  They felt that the their warships were wasted on such functions, and in some respects, not overly effective in the roles, either. 

Vice-Admiral de Irujo's staff had little difficulty drafting two simple designs, which are quickly being put into service.

The Iscuande class sloops are intended for ocean-going work, patrolling GC sealanes and escorting merchants in areas where bandits may be an issue.  They have a modest armament, include a twin torpedo carriage aft.  They are also equipped with steam launches and accommodation for a half-platoon of marine constables to facilitate ship inspections.  The upper hull and deck are protected against small-arms fire in the event that an inspection doesn't go too well.

The El Banco class is a smaller type intended for coastal use.  Being close to home waters, they have left out the torpedoes and armor.  Since they're fairly small, it's envisioned that they will go alongside to undertake boardings, so steam launches are omitted.  They have accommodation for a squad of marine constables for inspections.

Both classes are trimmed for adequate steadiness and good stability, as they are more likely to be out in stormy weather than torpedoboats.



Iscuande, laid down 1906

Displacement:
   857 t light; 883 t standard; 1,077 t normal; 1,233 t full load

Dimensions: Length overall / water x beam x draught
   231.35 ft / 229.66 ft x 32.81 ft x 10.01 ft (normal load)
   70.52 m / 70.00 m x 10.00 m  x 3.05 m

Armament:
      1 - 3.94" / 100 mm guns in single mounts, 30.51lbs / 13.84kg shells, 1906 Model
     Breech loading gun in a deck mount with hoist
     on centreline forward, 1 raised gun
      2 - 1.85" / 47.0 mm guns in single mounts, 3.17lbs / 1.44kg shells, 1906 Model
     Quick firing guns in deck mounts
     on centerline aft, 1 raised gun
      2 - 0.31" / 8.0 mm guns in single mounts, 0.02lbs / 0.01kg shells, 1906 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 37 lbs / 17 kg
   Shells per gun, main battery: 200
   2 - 18.0" / 457 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Ends:   Unarmoured
   Upper:   0.59" / 15 mm   149.28 ft / 45.50 m   8.01 ft / 2.44 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.98" / 25 mm   0.98" / 25 mm      0.98" / 25 mm
   2nd:   0.98" / 25 mm         -               -
   3rd:   0.39" / 10 mm         -               -

   - Armour deck: 0.59" / 15 mm, Conning tower: 1.18" / 30 mm

Machinery:
   Coal fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 1,600 ihp / 1,193 Kw = 15.02 kts
   Range 6,000nm at 10.00 kts (Bunkerage = 350 tons)

Complement:
   93 - 122

Cost:
   £0.066 million / $0.263 million

Distribution of weights at normal displacement:
   Armament: 5 tons, 0.4 %
   Armour: 93 tons, 8.6 %
      - Belts: 30 tons, 2.8 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 5 tons, 0.4 %
      - Armour Deck: 55 tons, 5.1 %
      - Conning Tower: 3 tons, 0.2 %
   Machinery: 229 tons, 21.2 %
   Hull, fittings & equipment: 434 tons, 40.3 %
   Fuel, ammunition & stores: 220 tons, 20.5 %
   Miscellaneous weights: 97 tons, 9.0 %
      -50 t:  Accommodation for 25 marine constables
      -10 t:  Wireless
      -20 t:  Steam launches and derrick
      -15 t:  Weight reserve
      -2 t:  Torpedoes
   

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     2,227 lbs / 1,010 Kg = 73.0 x 3.9 " / 100 mm shells or 0.8 torpedoes
   Stability (Unstable if below 1.00): 1.27
   Metacentric height 1.4 ft / 0.4 m
   Roll period: 11.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.07
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.500
   Length to Beam Ratio: 7.00 : 1
   'Natural speed' for length: 15.15 kts
   Power going to wave formation at top speed: 44 %
   Trim (Max stability = 0, Max steadiness = 100): 25
   Bow angle (Positive = bow angles forward): 5.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19.36 ft / 5.90 m
      - Forecastle (20 %):   19.36 ft / 5.90 m (15.42 ft / 4.70 m aft of break)
      - Mid (50 %):      15.42 ft / 4.70 m
      - Quarterdeck (15 %):   15.42 ft / 4.70 m
      - Stern:      15.42 ft / 4.70 m
      - Average freeboard:   16.21 ft / 4.94 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 82.8 %
      - Above water (accommodation/working, high = better): 137.3 %
   Waterplane Area: 5,020 Square feet or 466 Square metres
   Displacement factor (Displacement / loading): 158 %
   Structure weight / hull surface area: 41 lbs/sq ft or 200 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.80
      - Longitudinal: 7.44
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is excellent
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather



El Banco, laid down 1906

Displacement:
   371 t light; 382 t standard; 420 t normal; 451 t full load

Dimensions: Length overall / water x beam x draught
   168.93 ft / 164.04 ft x 24.28 ft x 8.20 ft (normal load)
   51.49 m / 50.00 m x 7.40 m  x 2.50 m

Armament:
      1 - 2.56" / 65.0 mm guns in single mounts, 8.38lbs / 3.80kg shells, 1906 Model
     Breech loading gun in deck mount
     on centreline forward, 1 raised gun
      2 - 1.85" / 47.0 mm guns in single mounts, 3.17lbs / 1.44kg shells, 1906 Model
     Quick firing guns in deck mounts
     on side, all amidships, 1 raised mount
      2 - 0.31" / 8.0 mm guns in single mounts, 0.02lbs / 0.01kg shells, 1906 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 15 lbs / 7 kg
   Shells per gun, main battery: 200

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.98" / 25 mm         -               -
   2nd:   0.98" / 25 mm         -               -
   3rd:   0.39" / 10 mm         -               -

Machinery:
   Coal fired boilers, complex reciprocating steam engines,
   Direct drive, 2 shafts, 1,000 ihp / 746 Kw = 15.09 kts
   Range 2,000nm at 10.00 kts (Bunkerage = 69 tons)

Complement:
   46 - 60

Cost:
   £0.035 million / $0.138 million

Distribution of weights at normal displacement:
   Armament: 2 tons, 0.4 %
   Armour: 3 tons, 0.7 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 3 tons, 0.7 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 143 tons, 34.0 %
   Hull, fittings & equipment: 173 tons, 41.3 %
   Fuel, ammunition & stores: 49 tons, 11.6 %
   Miscellaneous weights: 50 tons, 11.9 %
      -24 t:  Accommodation for 12 marine constables
      -10 t:  Wireless
      -16 t:  Weight reserve

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     425 lbs / 193 Kg = 50.7 x 2.6 " / 65 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.24
   Metacentric height 0.9 ft / 0.3 m
   Roll period: 10.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.05
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.450
   Length to Beam Ratio: 6.76 : 1
   'Natural speed' for length: 12.81 kts
   Power going to wave formation at top speed: 52 %
   Trim (Max stability = 0, Max steadiness = 100): 25
   Bow angle (Positive = bow angles forward): 5.00 degrees
   Stern overhang: 3.28 ft / 1.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18.37 ft / 5.60 m
      - Forecastle (20 %):   18.37 ft / 5.60 m (11.15 ft / 3.40 m aft of break)
      - Mid (50 %):      11.15 ft / 3.40 m
      - Quarterdeck (15 %):   11.15 ft / 3.40 m
      - Stern:      11.15 ft / 3.40 m
      - Average freeboard:   12.60 ft / 3.84 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 126.8 %
      - Above water (accommodation/working, high = better): 117.3 %
   Waterplane Area: 2,540 Square feet or 236 Square metres
   Displacement factor (Displacement / loading): 119 %
   Structure weight / hull surface area: 30 lbs/sq ft or 145 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.79
      - Longitudinal: 10.03
      - Overall: 1.01
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

[Borys]

Ahoj!
The smaller one will make a nice minesweeper ...
Borys

[The Rock Doctor]

Perhaps.  Purpose-built minesweepers aren't a common thing at this point in time, I think, so I'm contemplating whether conversion of those rickety ICN-built torpedo boats might be worthwhile.