Harbour Patrol Craft

[The Rock Doctor]

Time to break this out separately.

[The Rock Doctor]

Type 1895 Harbour Inspection Boat

80 units built since 1895 to inspect merchant shipping, patrol coastlines, and all that jazz.
8 more units laid down 1/11
8 more units laid down 2/11
8 more units laid down 1/12

-52 units scrapped 1925
-52 units scrapped 1925, none in service.

Enter ship name, Enter country Enter ship type laid down 1896

Displacement:
   38 t light; 40 t standard; 40 t normal; 40 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (65.62 ft / 65.62 ft) x 13.12 ft x (2.95 / 2.97 ft)
   (20.00 m / 20.00 m) x 4.00 m  x (0.90 / 0.90 m)

Armament:
      1 - 1.97" / 50.0 mm 40.0 cal gun - 3.66lbs / 1.66kg shells, 100 per gun
     Quick firing gun in deck mount, 1896 Model
     1 x Single mount on centreline, forward deck centre
      3 - 0.39" / 10.0 mm 40.0 cal guns - 0.03lbs / 0.01kg shells, 5,000 per gun
     Machine guns in deck mounts, 1896 Model
     1 x Single mount on centreline, aft deck centre
     2 x Single mounts on sides amidships
      Weight of broadside 4 lbs / 2 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.39" / 10 mm   0.20" / 5 mm            -
   2nd:   0.20" / 5 mm         -               -

Machinery:
   Coal fired boilers, simple reciprocating steam engines,
   Direct drive, 2 shafts, 47 ihp / 35 Kw = 9.00 kts
   Range 100nm at 5.00 kts
   Bunker at max displacement = 1 tons (100% coal)

Complement:
   7 - 10

Cost:
   £0.003 million / $0.011 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 2.0 %
      - Guns: 1 tons, 2.0 %
   Armour: 3 tons, 6.5 %
      - Armament: 3 tons, 6.5 %
   Machinery: 9 tons, 21.5 %
   Hull, fittings & equipment: 16 tons, 41.1 %
   Fuel, ammunition & stores: 2 tons, 3.9 %
   Miscellaneous weights: 10 tons, 25.0 %
      - On freeboard deck: 10 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     98 lbs / 45 Kg = 25.7 x 2.0 " / 50 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.45
   Metacentric height 0.5 ft / 0.1 m
   Roll period: 8.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.05
   Seaboat quality  (Average = 1.00): 1.86

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.550 / 0.551
   Length to Beam Ratio: 5.00 : 1
   'Natural speed' for length: 8.10 kts
   Power going to wave formation at top speed: 53 %
   Trim (Max stability = 0, Max steadiness = 100): 27
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  4.92 ft / 1.50 m,  4.92 ft / 1.50 m
      - Forward deck:   30.00 %,  4.92 ft / 1.50 m,  4.92 ft / 1.50 m
      - Aft deck:   35.00 %,  4.92 ft / 1.50 m,  4.92 ft / 1.50 m
      - Quarter deck:   15.00 %,  4.92 ft / 1.50 m,  4.92 ft / 1.50 m
      - Average freeboard:      4.92 ft / 1.50 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 76.4 %
      - Above water (accommodation/working, high = better): 80.5 %
   Waterplane Area: 601 Square feet or 56 Square metres
   Displacement factor (Displacement / loading): 125 %
   Structure weight / hull surface area: 18 lbs/sq ft or 87 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.93
      - Longitudinal: 5.55
      - Overall: 1.11
   Excellent machinery, storage, compartmentation space
   Cramped accommodation and workspace room
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

[The Rock Doctor]

Type 1919 Harbour Defence Boat

To be built in large quantities to undertake short-range patrol duties, customs work, and so forth near Union ports and along the shores.  The draft will allow for some degree of riverine duties as required.

The miscellaneous weight allows for embarkation of a customs inspection team or marine squad or the like on a short-term basis.

These units are built to civilian standards and will replace the Type 1895 Harbour Inspection Boat in service.

#1 to #61, laid down 1919
#62 to #77, laid down 1920
#78 to #85, laid down 1921
#86 to #93, laid down 1922
#94 to #99, laid down 1923
#100 to #105, laid down 1924
#106 to #111, laid down 1925

Enter ship name, Enter country Enter ship type laid down 1919

Displacement:
   47 t light; 48 t standard; 50 t normal; 51 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (86.53 ft / 82.02 ft) x 13.12 ft x (2.95 / 3.01 ft)
   (26.37 m / 25.00 m) x 4.00 m  x (0.90 / 0.92 m)

Armament:
      1 - 1.97" / 50.0 mm 45.0 cal gun - 3.85lbs / 1.74kg shells, 100 per gun
     Quick firing gun in deck mount, 1919 Model
     1 x Single mount on centreline, forward deck centre
      3 - 0.39" / 10.0 mm 45.0 cal guns - 0.03lbs / 0.01kg shells, 4,000 per gun
     Machine guns in deck mounts, 1919 Model
     2 x Single mounts on sides amidships
     1 x Single mount on centreline, aft deck centre
      Weight of broadside 4 lbs / 2 kg

Machinery:
   Coal and oil fired boilers, complex reciprocating steam engines,
   Direct drive, 1 shaft, 295 ihp / 220 Kw = 14.04 kts
   Range 270nm at 10.00 kts
   Bunker at max displacement = 3 tons (90% coal)

Complement:
   9 - 12

Cost:
   £0.010 million / $0.040 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 1.9 %
      - Guns: 1 tons, 1.9 %
   Machinery: 19 tons, 37.9 %
   Hull, fittings & equipment: 22 tons, 44.2 %
   Fuel, ammunition & stores: 3 tons, 6.0 %
   Miscellaneous weights: 5 tons, 10.0 %
      - On freeboard deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     58 lbs / 26 Kg = 15.2 x 2.0 " / 50 mm shells or 0.1 torpedoes
   Stability (Unstable if below 1.00): 1.16
   Metacentric height 0.3 ft / 0.1 m
   Roll period: 9.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.09
   Seaboat quality  (Average = 1.00): 1.27

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.550 / 0.553
   Length to Beam Ratio: 6.25 : 1
   'Natural speed' for length: 9.06 kts
   Power going to wave formation at top speed: 67 %
   Trim (Max stability = 0, Max steadiness = 100): 55
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 1.64 ft / 0.50 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   25.00 %,  7.87 ft / 2.40 m,  6.89 ft / 2.10 m
      - Forward deck:   25.00 %,  6.89 ft / 2.10 m,  5.91 ft / 1.80 m
      - Aft deck:   35.00 %,  5.91 ft / 1.80 m,  5.91 ft / 1.80 m
      - Quarter deck:   15.00 %,  5.91 ft / 1.80 m,  5.91 ft / 1.80 m
      - Average freeboard:      6.37 ft / 1.94 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 128.0 %
      - Above water (accommodation/working, high = better): 94.2 %
   Waterplane Area: 729 Square feet or 68 Square metres
   Displacement factor (Displacement / loading): 110 %
   Structure weight / hull surface area: 16 lbs/sq ft or 76 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.78
      - Longitudinal: 8.56
      - Overall: 1.00
   Cramped machinery, storage, compartmentation space
   Adequate accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

[The Rock Doctor]

Type 1926 Harbour Patrol Boat

Alternate take on the harbour patrol boat.  Most significantly, it's got a bit of protection, and that means it's mil-spec and not mercantile construction.  So full cost, whereas previous builds have all been cheap and mercantile.

#1-6, laid down 1926
#7-14, laid down 1927
#15-22, laid down 1928
#23-30, laid down 1929
#31-38, laid down 1930

Enter ship name, Enter country Enter ship type laid down 1925

Displacement:
   55 t light; 57 t standard; 58 t normal; 59 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (82.12 ft / 78.74 ft) x 13.12 ft x (3.94 / 3.98 ft)
   (25.03 m / 24.00 m) x 4.00 m  x (1.20 / 1.21 m)

Armament:
      1 - 1.97" / 50.0 mm 45.0 cal gun - 3.85lbs / 1.75kg shells, 150 per gun
     Quick firing gun in deck mount, 1925 Model
     1 x Single mount on centreline ends, evenly spread
      2 - 0.59" / 15.0 mm 90.0 cal guns - 0.12lbs / 0.05kg shells, 4,000 per gun
     Machine guns in deck mounts, 1925 Model
     1 x Single mount on centreline, forward deck aft
      1 raised mount - superfiring
     1 x Single mount on centreline, aft deck centre
      Weight of broadside 4 lbs / 2 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.79" / 20 mm   0.12" / 3 mm            -
   2nd:   0.59" / 15 mm         -               -

   - Conning towers: Forward 0.79" / 20 mm,  Aft 0.00" / 0 mm

Machinery:
   Diesel Internal combustion motors,
   Geared drive, 2 shafts, 402 shp / 300 Kw = 14.78 kts
   Range 300nm at 10.00 kts
   Bunker at max displacement = 2 tons

Complement:
   9 - 13

Cost:
   £0.013 million / $0.053 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 1.8 %
   Armour: 3 tons, 5.6 %
      - Armament: 3 tons, 5.2 %
      - Conning Tower: 0 tons, 0.4 %
   Machinery: 13 tons, 22.4 %
   Hull, fittings & equipment: 18 tons, 31.6 %
   Fuel, ammunition & stores: 3 tons, 5.4 %
   Miscellaneous weights: 19 tons, 33.0 %
      - Hull below water: 12 tons
      - On freeboard deck: 6 tons
      - Above deck: 1 tons

Fittings:
-7 t:  D-E drive, BW
-5 t:  Basic Hydrophone Paackage, BW
-2 t:  Depth charges, FD (20 x 90 kg DC)
-4 t:  Passengers or deck cargo, FD
-1 t:  Searchlight, AD

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     72 lbs / 33 Kg = 18.9 x 2.0 " / 50 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 0.3 ft / 0.1 m
   Roll period: 9.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.12
   Seaboat quality  (Average = 1.00): 1.30

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.500 / 0.502
   Length to Beam Ratio: 6.00 : 1
   'Natural speed' for length: 8.87 kts
   Power going to wave formation at top speed: 71 %
   Trim (Max stability = 0, Max steadiness = 100): 54
   Bow angle (Positive = bow angles forward): 10.00 degrees
   Stern overhang: 1.64 ft / 0.50 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  9.84 ft / 3.00 m,  7.87 ft / 2.40 m
      - Forward deck:   20.00 %,  7.87 ft / 2.40 m,  5.91 ft / 1.80 m
      - Aft deck:   45.00 %,  5.91 ft / 1.80 m,  5.91 ft / 1.80 m
      - Quarter deck:   15.00 %,  5.91 ft / 1.80 m,  5.91 ft / 1.80 m
      - Average freeboard:      6.65 ft / 2.03 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 102.0 %
      - Above water (accommodation/working, high = better): 90.5 %
   Waterplane Area: 688 Square feet or 64 Square metres
   Displacement factor (Displacement / loading): 113 %
   Structure weight / hull surface area: 13 lbs/sq ft or 63 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.58
      - Longitudinal: 8.57
      - Overall: 0.76

   Caution: Hull subject to strain in open-sea
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

[The Rock Doctor]

Type 1931 Harbour Patrol Boat

Incremental improvement on the 1926 model, with a 50mm AA gun rather than a QF.  Not sure why I used 1930 engines, but honestly won't make much if any difference on something this slow anyway.

Units #1 to #8, laid down 1931
Units #9 to #16, laid down 1932
Units #17 to #24, laid down 1933
Units #25 to #32, laid down 1934

Enter ship name, Enter country Enter ship type laid down 1930

Displacement:
   54 t light; 57 t standard; 58 t normal; 59 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (84.29 ft / 78.74 ft) x 13.12 ft x (3.94 / 3.98 ft)
   (25.69 m / 24.00 m) x 4.00 m  x (1.20 / 1.21 m)

Armament:
      1 - 1.97" / 50.0 mm 60.0 cal gun - 4.18lbs / 1.89kg shells, 500 per gun
     Anti-air gun in deck mount, 1930 Model
     1 x Single mount on centreline forward
      2 - 0.59" / 15.0 mm 90.0 cal guns - 0.12lbs / 0.05kg shells, 4,000 per gun
     Machine guns in deck mounts, 1930 Model
     1 x Single mount on centreline, aft deck centre
     1 x Single mount on centreline, forward deck aft
      1 raised mount
      Weight of broadside 4 lbs / 2 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0.59" / 15 mm   0.12" / 3 mm            -
   2nd:   0.59" / 15 mm         -               -

   - Conning towers: Forward 0.79" / 20 mm,  Aft 0.00" / 0 mm

Machinery:
   Diesel Internal combustion motors,
   Electric cruising motors plus geared drives, 2 shafts, 402 shp / 300 Kw = 14.78 kts
   Range 300nm at 10.00 kts
   Bunker at max displacement = 2 tons

Complement:
   9 - 13

Cost:
   £0.017 million / $0.067 million

Distribution of weights at normal displacement:
   Armament: 1 tons, 2.6 %
   Armour: 3 tons, 4.9 %
      - Armament: 3 tons, 4.4 %
      - Conning Tower: 0 tons, 0.4 %
   Machinery: 12 tons, 21.0 %
   Hull, fittings & equipment: 18 tons, 30.4 %
   Fuel, ammunition & stores: 4 tons, 6.8 %
   Miscellaneous weights: 20 tons, 34.4 %
      - Hull below water: 12 tons
      - On freeboard deck: 7 tons
      - Above deck: 1 tons

Fittings:
-5 t:  Basic hydrophones (BW)
-7 t:  D-E engines (BW)
-7 t:  Combination of depth charges and/or marine constable squad (FD)
-1 t:  Spotlight (AD)

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     73 lbs / 33 Kg = 19.1 x 2.0 " / 50 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.18
   Metacentric height 0.3 ft / 0.1 m
   Roll period: 9.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.13
   Seaboat quality  (Average = 1.00): 1.30

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.500 / 0.502
   Length to Beam Ratio: 6.00 : 1
   'Natural speed' for length: 8.87 kts
   Power going to wave formation at top speed: 71 %
   Trim (Max stability = 0, Max steadiness = 100): 54
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 1.97 ft / 0.60 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  9.84 ft / 3.00 m,  7.87 ft / 2.40 m
      - Forward deck:   20.00 %,  7.87 ft / 2.40 m,  5.91 ft / 1.80 m
      - Aft deck:   45.00 %,  5.91 ft / 1.80 m,  5.91 ft / 1.80 m
      - Quarter deck:   15.00 %,  5.91 ft / 1.80 m,  5.91 ft / 1.80 m
      - Average freeboard:      6.65 ft / 2.03 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 99.8 %
      - Above water (accommodation/working, high = better): 90.5 %
   Waterplane Area: 688 Square feet or 64 Square metres
   Displacement factor (Displacement / loading): 114 %
   Structure weight / hull surface area: 13 lbs/sq ft or 61 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.57
      - Longitudinal: 8.42
      - Overall: 0.75
   Caution: Hull subject to strain in open-sea
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily