TB-1, Inca Torpedo Gunboat laid down 1911
Displacement:
250 t light; 258 t standard; 301 t normal; 335 t full load
Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(180.45 ft / 177.17 ft) x 19.69 ft x (7.55 / 8.14 ft)
(55.00 m / 54.00 m) x 6.00 m x (2.30 / 2.48 m)
Armament:
2 - 2.56" / 65.0 mm 50.0 cal guns - 8.82lbs / 4.00kg shells, 200 per gun
Quick firing guns in deck mounts, 1909 Model
1 x Single mount on centreline, forward evenly spread
1 raised mount
1 x Single mount on centreline, aft evenly spread
Weight of broadside 18 lbs / 8 kg
Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.39" / 10 mm - -
Machinery:
Coal fired boilers, steam turbines,
Direct drive, 1 shaft, 6,450 shp / 4,812 Kw = 25.50 kts
Range 2,000nm at 12.00 kts
Bunker at max displacement = 78 tons (100% coal)
Complement:
35 - 46
Cost:
£0.032 million / $0.127 million
Distribution of weights at normal displacement:
Armament: 4 tons, 1.3 %
Armour: 2 tons, 0.6 %
- Armament: 2 tons, 0.6 %
Machinery: 158 tons, 52.5 %
Hull, fittings & equipment: 78 tons, 26.0 %
Fuel, ammunition & stores: 51 tons, 17.0 %
Miscellaneous weights: 8 tons, 2.7 %
- On freeboard deck: 8 tons
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
91 lbs / 41 Kg = 10.9 x 2.6 " / 65 mm shells or 0.1 torpedoes
Stability (Unstable if below 1.00): 1.47
Metacentric height 0.9 ft / 0.3 m
Roll period: 9.0 seconds
Steadiness - As gun platform (Average = 50 %): 44 %
- Recoil effect (Restricted arc if above 1.00): 0.08
Seaboat quality (Average = 1.00): 0.79
Hull form characteristics:
Hull has raised forecastle,
a ram bow and a cruiser stern
Block coefficient (normal/deep): 0.400 / 0.413
Length to Beam Ratio: 9.00 : 1
'Natural speed' for length: 13.31 kts
Power going to wave formation at top speed: 70 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): -10.00 degrees
Stern overhang: -3.28 ft / -1.00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 25.00 %, 11.29 ft / 3.44 m, 11.29 ft / 3.44 m
- Forward deck: 30.00 %, 8.01 ft / 2.44 m, 8.01 ft / 2.44 m
- Aft deck: 30.00 %, 8.01 ft / 2.44 m, 8.01 ft / 2.44 m
- Quarter deck: 15.00 %, 8.01 ft / 2.44 m, 8.01 ft / 2.44 m
- Average freeboard: 8.83 ft / 2.69 m
Ship tends to be wet forward
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 173.1 %
- Above water (accommodation/working, high = better): 88.4 %
Waterplane Area: 2,030 Square feet or 189 Square metres
Displacement factor (Displacement / loading): 51 %
Structure weight / hull surface area: 18 lbs/sq ft or 89 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 2.69
- Overall: 0.59
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is cramped
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather
Miscellaneous weight is as follows :
8t - 4x 450mm torpedoes. Two torpedoes fire forward from the "cheeks" like an E-boat, and two on a turntable in the rear.
Trial Speed: 29.88