Isfahan - to China, 1942
Azerbaijan - to Mexico, 1941
Isfahan, Persian Light Cruiser laid down 1930
Displacement:
4,102 t light; 4,278 t standard; 4,587 t normal; 4,833 t full load
Dimensions: Length overall / water x beam x draught
496.41 ft / 488.00 ft x 45.00 ft x 17.00 ft (normal load)
151.31 m / 148.74 m x 13.72 m x 5.18 m
Armament:
6 - 5.12" / 130 mm guns (2x3 guns), 75 lbs shells, 1921 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, evenly spread
4 - 1.97" / 50.0 mm guns (2x2 guns), 4 lbs shells, 1926 Model
Breech loading guns in deck mounts
on centreline ends, evenly spread, all raised mounts
12 - 0.98" / 25.0 mm guns (4x3 guns), 0.56lbs shells, 1926 Model
Breech loading guns in deck mounts
on side, evenly spread
Weight of broadside 423 lbs / 192 kg
Shells per gun, main battery: 350
4 - 24.0" / 609.6 mm above water torpedoes
Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 0.50" / 13 mm 1.50" / 38 mm
2nd: 1.00" / 25 mm - -
3rd: 1.00" / 25 mm - -
- Conning tower: 3.00" / 76 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 79,128 shp / 59,030 Kw = 36.50 kts
Range 2,000nm at 20.00 kts
Bunker at max displacement = 555 tons
Complement:
278 - 362
Cost:
£2.172 million / $8.690 million
Distribution of weights at normal displacement:
Armament: 53 tons, 1.2 %
Armour: 70 tons, 1.5 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 53 tons, 1.1 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 18 tons, 0.4 %
Machinery: 2,368 tons, 51.6 %
Hull, fittings & equipment: 1,560 tons, 34.0 %
Fuel, ammunition & stores: 485 tons, 10.6 %
Miscellaneous weights: 50 tons, 1.1 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,509 lbs / 684 Kg = 22.5 x 5.1 " / 130 mm shells or 0.5 torpedoes
Stability (Unstable if below 1.00): 1.18
Metacentric height 2.0 ft / 0.6 m
Roll period: 13.2 seconds
Steadiness - As gun platform (Average = 50 %): 76 %
- Recoil effect (Restricted arc if above 1.00): 0.31
Seaboat quality (Average = 1.00): 1.05
Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.430
Length to Beam Ratio: 10.84 : 1
'Natural speed' for length: 25.27 kts
Power going to wave formation at top speed: 64 %
Trim (Max stability = 0, Max steadiness = 100): 73
Bow angle (Positive = bow angles forward): 17.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 27.50 ft / 8.38 m
- Forecastle (20 %): 17.50 ft / 5.33 m
- Mid (50 %): 17.50 ft / 5.33 m
- Quarterdeck (15 %): 17.50 ft / 5.33 m
- Stern: 17.50 ft / 5.33 m
- Average freeboard: 18.30 ft / 5.58 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 177.9 %
- Above water (accommodation/working, high = better): 143.5 %
Waterplane Area: 14,319 Square feet or 1,330 Square metres
Displacement factor (Displacement / loading): 86 %
Structure weight / hull surface area: 59 lbs/sq ft or 286 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.68
- Longitudinal: 1.75
- Overall: 0.75
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Isfahan refit - 1941
The Isfahan received a refit similar to the Babr class cruisers to serve as the AA companion to the new heavy cruiser.
A change in naval strategy in late 1941/early 1942 prompted her sale.
Isfahan, Persia Light Cruiser laid down 1930 (Engine 1941)
Displacement:
3,709 t light; 3,899 t standard; 4,587 t normal; 5,137 t full load
Dimensions: Length overall / water x beam x draught
496.41 ft / 488.00 ft x 45.00 ft x 17.00 ft (normal load)
151.31 m / 148.74 m x 13.72 m x 5.18 m
Armament:
4 - 5.12" / 130 mm guns (2x2 guns), 67.03lbs / 30.41kg shells, 1941 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread
4 - 4.13" / 105 mm guns (2x2 guns), 35.32lbs / 16.02kg shells, 1941 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, evenly spread, all raised mounts
18 - 1.57" / 40.0 mm guns (6x3 guns), 1.95lbs / 0.89kg shells, 1941 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, 2 raised mounts
8 - 0.79" / 20.0 mm guns (4x2 guns), 0.24lbs / 0.11kg shells, 1941 Model
Machine guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 447 lbs / 203 kg
Shells per gun, main battery: 350
4 - 24.0" / 610 mm above water torpedoes
Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.00" / 51 mm 0.50" / 13 mm 1.50" / 38 mm
2nd: 1.50" / 38 mm 0.50" / 13 mm 1.00" / 25 mm
3rd: 1.00" / 25 mm - -
4th: 0.50" / 13 mm - -
- Conning tower: 3.00" / 76 mm
Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 74,811 shp / 55,809 Kw = 36.00 kts
Range 10,000nm at 15.00 kts
Bunker at max displacement = 1,238 tons
Complement:
278 - 362
Cost:
£1.896 million / $7.585 million
Distribution of weights at normal displacement:
Armament: 56 tons, 1.2 %
Armour: 46 tons, 1.0 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 28 tons, 0.6 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 18 tons, 0.4 %
Machinery: 1,977 tons, 43.1 %
Hull, fittings & equipment: 1,570 tons, 34.2 %
Fuel, ammunition & stores: 878 tons, 19.1 %
Miscellaneous weights: 60 tons, 1.3 %
Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2,149 lbs / 975 Kg = 32.1 x 5.1 " / 130 mm shells or 0.6 torpedoes
Stability (Unstable if below 1.00): 1.24
Metacentric height 2.2 ft / 0.7 m
Roll period: 12.6 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.32
Seaboat quality (Average = 1.00): 1.09
Hull form characteristics:
Hull has a flush deck
and transom stern
Block coefficient: 0.430
Length to Beam Ratio: 10.84 : 1
'Natural speed' for length: 25.27 kts
Power going to wave formation at top speed: 63 %
Trim (Max stability = 0, Max steadiness = 100): 65
Bow angle (Positive = bow angles forward): 17.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 27.50 ft / 8.38 m
- Forecastle (20 %): 17.50 ft / 5.33 m
- Mid (50 %): 17.50 ft / 5.33 m
- Quarterdeck (15 %): 17.50 ft / 5.33 m
- Stern: 17.50 ft / 5.33 m
- Average freeboard: 18.30 ft / 5.58 m
Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 151.7 %
- Above water (accommodation/working, high = better): 143.5 %
Waterplane Area: 14,319 Square feet or 1,330 Square metres
Displacement factor (Displacement / loading): 102 %
Structure weight / hull surface area: 59 lbs/sq ft or 288 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.69
- Longitudinal: 1.78
- Overall: 0.75
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
40t-Fire direction and air search radars.
20t-misc