WesWorld

Siamese Ratanakosindra-class Coast Defense Ship laid down 1924

Displacement:
862 t light; 906 t standard; 1,000 t normal; 1,075 t full load

Dimensions: Length overall / water x beam x draught
167.22 ft / 166.00 ft x 37.00 ft x 10.75 ft (normal load)
50.97 m / 50.60 m x 11.28 m x 3.28 m

Armament:
2 - 6.00" / 152 mm guns in single mounts, 108.00lbs / 48.99kg shells, 1924 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread
4 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1924 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 2 raised mounts
4 - 0.51" / 13.0 mm guns in single mounts, 0.07lbs / 0.03kg shells, 1924 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts

Weight of broadside 270 lbs / 123 kg
Shells per gun, main battery: 150

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.50" / 64 mm 108.00 ft / 32.92 m 7.50 ft / 2.29 m
Ends: 1.25" / 32 mm 58.00 ft / 17.68 m 7.50 ft / 2.29 m
Main Belt covers 100 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.50" / 64 mm 1.25" / 32 mm 2.50" / 64 mm
2nd: 0.50" / 13 mm - -
3rd: 0.25" / 6 mm - -

- Armour deck: 2.00" / 51 mm, Conning tower: 2.50" / 64 mm

Machinery:
Oil fired boilers, complex reciprocating steam engines,
Geared drive, 2 shafts, 850 ihp / 634 Kw = 12.40 kts
Range 5,000nm at 10.00 kts (Bunkerage = 169 tons)

Complement:
88 - 115

Cost:
£0.202 million / $0.809 million

Distribution of weights at normal displacement:
Armament: 34 tons, 3.4 %
Armour: 307 tons, 30.7 %
- Belts: 112 tons, 11.2 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 34 tons, 3.4 %
- Armour Deck: 156 tons, 15.6 %
- Conning Tower: 5 tons, 0.5 %
Machinery: 49 tons, 4.9 %
Hull, fittings & equipment: 447 tons, 44.7 %
Fuel, ammunition & stores: 138 tons, 13.8 %
Miscellaneous weights: 25 tons, 2.5 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2,494 lbs / 1,131 Kg = 23.1 x 6.0 " / 152 mm shells or 1.5 torpedoes
Stability (Unstable if below 1.00): 1.27
Metacentric height 1.7 ft / 0.5 m
Roll period: 11.8 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.25
Seaboat quality (Average = 1.00): 1.78

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.530
Length to Beam Ratio: 4.49 : 1
'Natural speed' for length: 12.88 kts
Power going to wave formation at top speed: 50 %
Trim (Max stability = 0, Max steadiness = 100): 40
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: 14.00 ft / 4.27 m
- Forecastle (20 %): 14.00 ft / 4.27 m
- Mid (35 %): 14.00 ft / 4.27 m (7.00 ft / 2.13 m aft of break)
- Quarterdeck (15 %): 7.00 ft / 2.13 m
- Stern: 7.00 ft / 2.13 m
- Average freeboard: 9.45 ft / 2.88 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 46.1 %
- Above water (accommodation/working, high = better): 78.5 %
Waterplane Area: 4,207 Square feet or 391 Square metres
Displacement factor (Displacement / loading): 143 %
Structure weight / hull surface area: 73 lbs/sq ft or 359 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.20
- Longitudinal: 5.04
- Overall: 1.38
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is cramped
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Two units. Ratanakosindra, Ko Si Chang

Dhonburi, Siamese coast defense armourclad, laid down in South Africa 1933



Displacement:
1,883 t light; 1,992 t standard; 2,176 t normal; 2,323 t full load

Dimensions: Length overall / water x beam x draught
384.28 ft / 377.30 ft x 41.01 ft x 12.30 ft (normal load)
117.13 m / 115.00 m x 12.50 m x 3.75 m

Armament:
8 - 5.12" / 130 mm guns (4x2 guns), 67.03lbs / 30.41kg shells, 1933 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread, 2 raised mounts - superfiring
8 - 3.46" / 88.0 mm guns (4x2 guns), 20.79lbs / 9.43kg shells, 1933 Model
Breech loading guns in deck mounts
on side, all amidships
8 - 1.46" / 37.0 mm guns (4x2 guns), 1.95lbs / 0.89kg shells, 1933 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
12 - 0.79" / 20.0 mm guns (5 mounts), 0.24lbs / 0.11kg shells, 1933 Model
Anti-aircraft guns in deck mounts
on side, evenly spread

Weight of broadside 721 lbs / 327 kg
Shells per gun, main battery: 150

4 - 21.0" / 533 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 3.15" / 80 mm 221.78 ft / 67.60 m 9.84 ft / 3.00 m
Ends: Unarmoured
Main Belt covers 90% of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 3.15" / 80 mm 1.57" / 40 mm 2.76" / 70 mm
2nd: 0.98" / 25 mm - -
3rd: 0.59" / 15 mm - -
4th: 0.39" / 10 mm - -

- Armour deck: 1.38" / 35 mm, Conning tower: 3.15" / 80 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 13,405 shp / 10,000 Kw = 24.68 kts
Range 6,000nm at 12.00 kts
Bunker at max displacement = 331 tons

Complement:
159 - 207

Cost:
£0.927 million / $3.706 million

Distribution of weights at normal displacement:
Armament: 90 tons, 4.1%
Armour: 695 tons, 31.9%
- Belts: 291 tons, 13.4%
- Torpedo bulkhead: 0 tons, 0.0%
- Armament: 150 tons, 6.9%
- Armour Deck: 243 tons, 11.2%
- Conning Tower: 11 tons, 0.5%
Machinery: 388 tons, 17.9%
Hull, fittings & equipment: 709 tons, 32.6%
Fuel, ammunition & stores: 293 tons, 13.5%
Miscellaneous weights: 0 tons, 0.0%

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2,163 lbs / 981 Kg = 32.3 x 5.1 " / 130 mm shells or 0.9 torpedoes
Stability (Unstable if below 1.00): 1.18
Metacentric height 1.8 ft / 0.5 m
Roll period: 12.9 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.83
Seaboat quality (Average = 1.00): 1.80

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.400
Length to Beam Ratio: 9.20 : 1
'Natural speed' for length: 19.42 kts
Power going to wave formation at top speed: 50 %
Trim (Max stability = 0, Max steadiness = 100): 39
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: 21.00 ft / 6.40 m
- Forecastle (20%): 17.72 ft / 5.40 m
- Mid (70%): 17.72 ft / 5.40 m (9.84 ft / 3.00 m aft of break)
- Quarterdeck (15%): 9.84 ft / 3.00 m
- Stern: 9.84 ft / 3.00 m
- Average freeboard: 15.62 ft / 4.76 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 90.5%
- Above water (accommodation/working, high = better): 149.1%
Waterplane Area: 9,525 Square feet or 885 Square metres
Displacement factor (Displacement / loading): 99%
Structure weight / hull surface area: 43 lbs/sq ft or 209 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.45
- Overall: 0.55
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Two units: Dhonburi, Ko Lan

Ko Phai, Siamese Coast Defence Ship laid down 1933 (Engine 1935)

Displacement:
8,401 t light; 8,986 t standard; 10,072 t normal; 10,941 t full load

Dimensions: Length overall / water x beam x draught
408.22 ft / 393.70 ft x 70.87 ft (Bulges 79.07 ft) x 21.65 ft (normal load)
124.42 m / 120.00 m x 21.60 m (Bulges 24.10 m) x 6.60 m

Armament:
6 - 11.02" / 280 mm guns (2x3 guns), 793.66lbs / 360.00kg shells, 1919 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread
4 - 5.12" / 130 mm guns (2x2 guns), 67.03lbs / 30.40kg shells, 1933 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread, all raised mounts
8 - 5.12" / 130 mm guns (4x2 guns), 67.03lbs / 30.40kg shells, 1933 Model
Dual purpose guns in deck mounts with hoists
on side, evenly spread
24 - 1.57" / 40.0 mm guns (6x4 guns), 1.94lbs / 0.88kg shells, 1933 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
8 - 0.91" / 23.0 mm guns (4x2 guns), 0.37lbs / 0.17kg shells, 1928 Model
Anti-aircraft guns in deck mounts
on side ends, evenly spread, all raised mounts - superfiring
Weight of broadside 5,178 lbs / 2,349 kg
Shells per gun, main battery: 130

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 9.45" / 240 mm 255.91 ft / 78.00 m 9.84 ft / 3.00 m
Ends: 1.57" / 40 mm 137.76 ft / 41.99 m 9.84 ft / 3.00 m
Upper: 1.57" / 40 mm 255.91 ft / 78.00 m 12.99 ft / 3.96 m
Main Belt covers 100 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 10.0" / 255 mm 3.94" / 100 mm 7.09" / 180 mm
2nd: 1.57" / 40 mm 0.79" / 20 mm 0.98" / 25 mm
3rd: 1.57" / 40 mm 0.79" / 20 mm 0.98" / 25 mm
4th: 0.39" / 10 mm - -
5th: 0.39" / 10 mm - -

- Armour deck: 3.51" / 89 mm, Conning tower: 7.09" / 180 mm

Machinery:
Diesel Internal combustion generators,
Electric motors, 2 shafts, 13,747 shp / 10,255 Kw = 19.00 kts
Range 8,500nm at 15.00 kts
Bunker at max displacement = 1,956 tons

Complement:
502 - 653

Cost:
£3.850 million / $15.399 million

Distribution of weights at normal displacement:
Armament: 554 tons, 5.5 %
Armour: 3,279 tons, 32.6 %
- Belts: 1,361 tons, 13.5 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 615 tons, 6.1 %
- Armour Deck: 1,232 tons, 12.2 %
- Conning Tower: 71 tons, 0.7 %
Machinery: 391 tons, 3.9 %
Hull, fittings & equipment: 3,977 tons, 39.5 %
Fuel, ammunition & stores: 1,671 tons, 16.6 %
Miscellaneous weights: 150 tons, 2.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
17,556 lbs / 7,963 Kg = 26.2 x 11.0 " / 280 mm shells or 3.3 torpedoes
Stability (Unstable if below 1.00): 1.23
Metacentric height 4.4 ft / 1.3 m
Roll period: 15.9 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.45
Seaboat quality (Average = 1.00): 1.56

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.523
Length to Beam Ratio: 4.98 : 1
'Natural speed' for length: 19.84 kts
Power going to wave formation at top speed: 49 %
Trim (Max stability = 0, Max steadiness = 100): 45
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 6.56 ft / 2.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.85 ft / 6.66 m
- Forecastle (20 %): 21.85 ft / 6.66 m
- Mid (50 %): 16.99 ft / 5.18 m (12.14 ft / 3.70 m aft of break)
- Quarterdeck (15 %): 12.14 ft / 3.70 m
- Stern: 12.14 ft / 3.70 m
- Average freeboard: 16.27 ft / 4.96 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 58.1 %
- Above water (accommodation/working, high = better): 111.7 %
Waterplane Area: 18,987 Square feet or 1,764 Square metres
Displacement factor (Displacement / loading): 116 %
Structure weight / hull surface area: 142 lbs/sq ft or 695 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.89
- Longitudinal: 2.68
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Armor :
Upper and end armor is merely designed to stop HE
Belt armor is +1m above WL to -2m below WL, Upper belt is between +1m and average freeboard. Light armor is sufficient to exclude all pure HE rounds and GP bombs.


89.09mm Deck armor comes to top of belt. Deck is 105mm over vitals and 30mm over ends.

Shells / gun
40 AP
40 SAP
40 HE
10 practice

Misc :
10 tons for extra director and CIC
50 tons for seaplane & catapult on fantail

6 tons 'creep' 40hp motors arranged as fore/aft thrusters, and two stern motors.
134 tons misc

One Unit