Basically a repeat of the Arak with more modern engine
Astara, Persia Gunboat laid down 1937
Displacement:
1 247 t light; 1 300 t standard; 1 373 t normal; 1 431 t full load
Dimensions: Length overall / water x beam x draught
295,28 ft / 295,28 ft x 32,81 ft x 11,81 ft (normal load)
90,00 m / 90,00 m x 10,00 m x 3,60 m
Armament:
4 - 5,12" / 130 mm guns (2x2 guns), 67,03lbs / 30,40kg shells, 1937 Model
Dual purpose guns in deck mounts with hoists
on centreline, all forward, 1 raised mount - superfiring
8 - 1,57" / 40,0 mm guns (4x2 guns), 1,95lbs / 0,88kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on side, all amidships
4 - 1,57" / 40,0 mm guns (2x2 guns), 1,95lbs / 0,88kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on centreline, all aft, 1 raised mount - superfiring
Weight of broadside 292 lbs / 132 kg
Shells per gun, main battery: 150
4 - 24,0" / 609,6 mm above water torpedoes
Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 1,97" / 50 mm 191,93 ft / 58,50 m 6,89 ft / 2,10 m
Ends: Unarmoured
Upper: 1,18" / 30 mm 191,93 ft / 58,50 m 8,01 ft / 2,44 m
Main Belt covers 100 % of normal length
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1,97" / 50 mm 1,18" / 30 mm 1,18" / 30 mm
2nd: 0,79" / 20 mm - -
3rd: 0,79" / 20 mm - -
- Armour deck: 1,18" / 30 mm, Conning tower: 2,76" / 70 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 8 568 shp / 6 392 Kw = 24,00 kts
Range 2 000nm at 15,00 kts
Bunker at max displacement = 131 tons
Complement:
112 - 146
Cost:
£0,586 million / $2,346 million
Distribution of weights at normal displacement:
Armament: 36 tons, 2,7 %
Armour: 352 tons, 25,6 %
- Belts: 185 tons, 13,4 %
- Torpedo bulkhead: 0 tons, 0,0 %
- Armament: 23 tons, 1,7 %
- Armour Deck: 137 tons, 10,0 %
- Conning Tower: 7 tons, 0,5 %
Machinery: 237 tons, 17,3 %
Hull, fittings & equipment: 581 tons, 42,3 %
Fuel, ammunition & stores: 126 tons, 9,2 %
Miscellaneous weights: 40 tons, 2,9 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2 028 lbs / 920 Kg = 30,2 x 5,1 " / 130 mm shells or 0,9 torpedoes
Stability (Unstable if below 1.00): 1,04
Metacentric height 1,0 ft / 0,3 m
Roll period: 13,7 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0,70
Seaboat quality (Average = 1.00): 1,43
Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0,420
Length to Beam Ratio: 9,00 : 1
'Natural speed' for length: 19,99 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 49
Bow angle (Positive = bow angles forward): 0,00 degrees
Stern overhang: 0,00 ft / 0,00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 19,03 ft / 5,80 m
- Forecastle (20 %): 13,12 ft / 4,00 m
- Mid (50 %): 12,04 ft / 3,67 m
- Quarterdeck (15 %): 12,04 ft / 3,67 m
- Stern: 12,04 ft / 3,67 m
- Average freeboard: 12,89 ft / 3,93 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 80,5 %
- Above water (accommodation/working, high = better): 82,4 %
Waterplane Area: 6 270 Square feet or 582 Square metres
Displacement factor (Displacement / loading): 119 %
Structure weight / hull surface area: 52 lbs/sq ft or 252 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,79
- Longitudinal: 2,84
- Overall: 0,90
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
Good seaboat, rides out heavy weather easily