1936 HTMS Sukhothai

HTMS Sukhothai, Siam Coastal Defense Ship laid down 1936

Displacement:
	1,840 t light; 2,000 t standard; 2,376 t normal; 2,677 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
	(250.02 ft / 242.78 ft) x 55.77 ft x (13.45 / 14.72 ft)
	(76.21 m / 74.00 m) x 17.00 m  x (4.10 / 4.49 m)

Armament:
      4 - 10.00" / 254 mm 45.0 cal guns - 496.04lbs / 225.00kg shells, 80 per gun
	  Breech loading guns in turret on barbette mounts, 1936 Model
	  1 x Twin mount on centreline, aft deck centre
	  1 x Twin mount on centreline, forward deck centre
      4 - 4.13" / 105 mm 50.0 cal guns - 35.27lbs / 16.00kg shells, 250 per gun
	  Dual purpose guns in deck and hoist mounts, 1932 Model
	  2 x Single mounts on sides amidships
	  2 x Single mounts on centreline, evenly spread
		2 raised mounts
      16 - 0.79" / 20.0 mm 60.0 cal guns - 0.26lbs / 0.12kg shells, 2,000 per gun
	  Anti-air guns in deck mounts, 1936 Model
	  8 x Single mounts on sides, evenly spread
		8 raised mounts
	  8 x Single mounts on sides, evenly spread
		8 double raised mounts
      Weight of broadside 2,129 lbs / 966 kg

Armour:
   - Belts:		Width (max)	Length (avg)		Height (avg)
	Main:	1.97" / 50 mm	150.52 ft / 45.88 m	8.37 ft / 2.55 m
	Ends:	Unarmoured
	  Main Belt covers 95 % of normal length

   - Torpedo Bulkhead - Strengthened structural bulkheads:
		0.98" / 25 mm	150.52 ft / 45.88 m	16.40 ft / 5.00 m
	Beam between torpedo bulkheads 52.49 ft / 16.00 m

   - Gun armour:	Face (max)	Other gunhouse (avg)	Barbette/hoist (max)
	Main:	3.94" / 100 mm	0.39" / 10 mm		0.98" / 25 mm
	2nd:	0.12" / 3 mm	0.12" / 3 mm		0.12" / 3 mm

   - Armoured deck - single deck:
	For and Aft decks: 0.98" / 25 mm

   - Conning towers: Forward 3.94" / 100 mm, Aft 0.00" / 0 mm

Machinery:
	Diesel Internal combustion motors,
	Geared drive, 1 shaft, 3,371 shp / 2,515 Kw = 16.00 kts
	Range 12,000nm at 12.00 kts
	Bunker at max displacement = 677 tons

Complement:
	169 - 221

Cost:
	£1.490 million / $5.960 million

Distribution of weights at normal displacement:
	Armament: 498 tons, 21.0 %
	   - Guns: 498 tons, 21.0 %
	Armour: 377 tons, 15.9 %
	   - Belts: 115 tons, 4.8 %
	   - Torpedo bulkhead: 90 tons, 3.8 %
	   - Armament: 37 tons, 1.5 %
	   - Armour Deck: 120 tons, 5.0 %
	   - Conning Tower: 15 tons, 0.6 %
	Machinery: 92 tons, 3.9 %
	Hull, fittings & equipment: 873 tons, 36.8 %
	Fuel, ammunition & stores: 536 tons, 22.6 %
	Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
	Survivability (Non-critical penetrating hits needed to sink ship):
	  2,654 lbs / 1,204 Kg = 5.3 x 10.0 " / 254 mm shells or 1.1 torpedoes
	Stability (Unstable if below 1.00): 1.37
	Metacentric height 3.6 ft / 1.1 m
	Roll period: 12.3 seconds
	Steadiness	- As gun platform (Average = 50 %): 72 %
			- Recoil effect (Restricted arc if above 1.00): 0.38
	Seaboat quality  (Average = 1.00): 1.04

Hull form characteristics:
	Hull has a flush deck,
	  a normal bow and a round stern
	Block coefficient (normal/deep): 0.457 / 0.470
	Length to Beam Ratio: 4.35 : 1
	'Natural speed' for length: 15.58 kts
	Power going to wave formation at top speed: 52 %
	Trim (Max stability = 0, Max steadiness = 100): 70
	Bow angle (Positive = bow angles forward): 15.00 degrees
	Stern overhang: 3.28 ft / 1.00 m
	Freeboard (% = length of deck as a percentage of waterline length):
				Fore end,	 Aft end
	   - Forecastle:	23.00 %,  14.76 ft / 4.50 m,  9.19 ft / 2.80 m
	   - Forward deck:	30.00 %,  9.19 ft / 2.80 m,  6.56 ft / 2.00 m
	   - Aft deck:	32.00 %,  6.56 ft / 2.00 m,  6.56 ft / 2.00 m
	   - Quarter deck:	15.00 %,  6.56 ft / 2.00 m,  6.56 ft / 2.00 m
	   - Average freeboard:		8.07 ft / 2.46 m
	Ship tends to be wet forward

Ship space, strength and comments:
	Space	- Hull below water (magazines/engines, low = better): 95.1 %
		- Above water (accommodation/working, high = better): 67.2 %
	Waterplane Area: 8,284 Square feet or 770 Square metres
	Displacement factor (Displacement / loading): 94 %
	Structure weight / hull surface area: 114 lbs/sq ft or 556 Kg/sq metre
	Hull strength (Relative):
		- Cross-sectional: 0.88
		- Longitudinal: 2.88
		- Overall: 1.00
	Adequate machinery, storage, compartmentation space
	Cramped accommodation and workspace room
	Ship has slow, easy roll, a good, steady gun platform

Scaled down VAINAMOINEN class coastal defense ship, to be built at Turku, Finland.

254mm/45 Bofors
105mm/50 Bofors M1932
Madsen 20 60 M36

Torpedo bulkhead extends to upper deck as splinter bulkhead.
20mm guns preferred to be mounted in twin or quad mountings if possible.