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Lanao class, Philippine Utility Landing Ship laid down 1942

Displacement: 940 t light; 986 t standard; 1,225 t normal; 1,417 t full load

Dimensions: Length overall / water x beam x draught

263.29 ft / 246.06 ft x 29.86 ft x 9.48 ft (normal load) [80.25 m / 75.00 m x 9.10 m x 2.89 m]

Armament:

4 - 1.38" / 35.0 mm guns (2x2 guns), 1.31lbs / 0.59kg shells, 1942 Model Anti-aircraft guns in deck mounts on centreline ends, evenly spread
4 - 0.59" / 15.0 mm guns (2x2 guns), 0.10lbs / 0.05kg shells, 1942 Model Machine guns in deck mounts on side, all amidships, all raised mounts - superfiring
Weight of broadside 6 lbs / 3 kg
Shells per gun, main battery: 6,000

Armour:

Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.59" / 15 mm 0.59" / 15 mm -

Conning tower: 0.98" / 25 mm

Machinery:

Diesel Internal combustion motors, Geared drive, 2 shafts, 1,733 shp / 1,293 Kw = 15.00 kts
Range 12,000nm at 12.00 kts
Bunker at max displacement = 431 tons

Complement: 103 - 134

Cost: £0.253 million / $1.014 million

Distribution of weights at normal displacement:

Armament: 1 tons, 0.1 %
Armour: 4 tons, 0.3 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 2 tons, 0.1 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 2 tons, 0.2 %
Machinery: 45 tons, 3.7 %
Hull, fittings & equipment: 540 tons, 44.1 %
Fuel, ammunition & stores: 285 tons, 23.3 %
Miscellaneous weights: 350 tons, 28.6 %

Overall survivability and seakeeping ability:

Survivability (Non-critical penetrating hits needed to sink ship): 3,333 lbs / 1,512 Kg = 2,547.7 x 1.4 " / 35 mm shells or 1.6 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 1.0 ft / 0.3 m
Roll period: 12.7 seconds
Steadiness - As gun platform (Average = 50 %): 58 %
- Recoil effect (Restricted arc if above 1.00): 0.01
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:

Hull has raised forecastle
Block coefficient: 0.616
Length to Beam Ratio: 8.24 : 1
'Natural speed' for length: 15.69 kts
Power going to wave formation at top speed: 43 %
Trim (Max stability = 0, Max steadiness = 100): 29
Bow angle (Positive = bow angles forward): 45.00 degrees
Stern overhang: 0.82 ft / 0.25 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 16.40 ft / 5.00 m
- Forecastle (20 %): 14.44 ft / 4.40 m (11.15 ft / 3.40 m aft of break)
- Mid (50 %): 11.15 ft / 3.40 m
- Quarterdeck (25 %): 11.15 ft / 3.40 m
- Stern: 11.15 ft / 3.40 m
- Average freeboard: 11.97 ft / 3.65 m
Ship tends to be wet forward

Ship space, strength and comments:

Space - Hull below water (magazines/engines, low = better): 46.5 %
- Above water (accommodation/working, high = better): 112.5 %
Waterplane Area: 5,451 Square feet or 506 Square metres
Displacement factor (Displacement / loading): 272 %
Structure weight / hull surface area: 58 lbs/sq ft or 281 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.37
- Longitudinal: 3.53
- Overall: 1.50
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is adequate
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Additional hull stength represents strengthening for beaching operations

Miscellaneous weight represents cargo carried - up to 350 tons of tanks and vehicles, 350 tons of supplies or 175 troops over short distances.

Light displacement 940 tons, less one half miscellaneous weight (350 tons) = 765 tons cost to construct


- LSTs are built to special rules because of them being a mix of a freighter and a warship
- The miscellaneous weight of LST is halved into deductible and non-deductible (50/50)
- The deductible weight is taken off the ships light displacement and so building time and building costs
- Otherwise all normal building rules apply
- For scrapping LST only the reduced weight is used for calculation.
- Any landing craft carried aboard the LST shall be purchased separately under light craft rules