WesWorld

Persia is issuing a request for proposals for 6 Torpedoboats. They have to carry at least 6 18" Torpedotubes and have top speed of at least 40Kts

Wait, I'm confused. Are you asking for a torpedo boat tender, or torpedo boats?

The only thing I can think of with such speed +24" torpedoes...

Quoted

Originally posted by Brockpaine
Wait, I'm confused. Are you asking for a torpedo boat tender, or torpedo boats?

Sorry, bad English now clarified

Motor torpedo boats?

24" torpedoes on them would be rather a waste given the likely engagement ranges. Mush easier with 18" torpedoes that take up less space and are easier to handle.

Otherwise, Shimakaze or Capitani Romani are the only other choices. Actually, for service speed over 40knts, the Romanis are the only choice. Its a shame SS doesn't sim them very well.

Revised RfP

No takers?

Heh, it seems that SATSUMA and SEAR have created alot of "contagious" states.

As Turkey I might offer the Agri class boats but they fall short of the specifications and their a B*@tch to sim with the latest SS and "gentlemans rules".

40 knots and six torpedoes is tough, in 1935. Germany has a new S-boat design (the S-boat 1935 design), but it carries 533mm torpedoes and only 4 of them, though it comes very close to your desired speed (at 39.8 knots).

Nordmark issues the following design, which it views as being suitable for the Persian Navy's requirements.
Though not meeting the requirement for speed, the design does have a 2.5-3knot speed advantage over most modern destroyers, and does mount 8-18inch Torpedo tubes, with capacity for 16 torpedoes (8 in tubes, plus 8 reloads) to be carried.

Fast class, Persia Fast Torpedo Boat laid down 1935

Displacement:
1,993 t light; 2,071 t standard; 2,148 t normal; 2,210 t full load

Dimensions: Length overall / water x beam x draught
394.41 ft / 390.00 ft x 37.80 ft x 12.00 ft (normal load)
120.22 m / 118.87 m x 11.52 m x 3.66 m

Armament:
6 - 3.00" / 76.2 mm guns (3x2 guns), 13.50lbs / 6.12kg shells, 1935 Model
Dual purpose guns in deck mounts with hoists
on centreline ends, majority forward, 1 raised mount - superfiring
4 - 1.46" / 37.0 mm guns (1x4 guns), 1.65lbs / 0.75kg shells, 1935 Model
Anti-aircraft guns in deck mount
on centreline aft, all raised guns - superfiring
8 - 0.79" / 20.0 mm guns in single mounts, 0.27lbs / 0.12kg shells, 1935 Model
Machine guns in deck mounts
on side, all amidships, 4 raised mounts - superfiring
Weight of broadside 90 lbs / 41 kg
Shells per gun, main battery: 640
8 - 18.0" / 457.2 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.00" / 25 mm 0.50" / 13 mm -
2nd: 0.50" / 13 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 61,264 shp / 45,703 Kw = 37.50 kts
Range 1,505nm at 15.00 kts
Bunker at max displacement = 139 tons

Complement:
157 - 205

Cost:
£1.328 million / $5.312 million

Distribution of weights at normal displacement:
Armament: 11 tons, 0.5 %
Armour: 8 tons, 0.4 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 8 tons, 0.4 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 1,298 tons, 60.4 %
Hull, fittings & equipment: 662 tons, 30.8 %
Fuel, ammunition & stores: 155 tons, 7.2 %
Miscellaneous weights: 15 tons, 0.7 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
476 lbs / 216 Kg = 35.2 x 3.0 " / 76 mm shells or 0.3 torpedoes
Stability (Unstable if below 1.00): 1.25
Metacentric height 1.7 ft / 0.5 m
Roll period: 12.0 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.11
Seaboat quality (Average = 1.00): 0.97

Hull form characteristics:
Hull has raised forecastle, rise forward of midbreak
and transom stern
Block coefficient: 0.425
Length to Beam Ratio: 10.32 : 1
'Natural speed' for length: 22.70 kts
Power going to wave formation at top speed: 70 %
Trim (Max stability = 0, Max steadiness = 100): 72
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 25.00 ft / 7.62 m
- Forecastle (40 %): 21.00 ft / 6.40 m (20.00 ft / 6.10 m aft of break)
- Mid (40 %): 20.00 ft / 6.10 m (14.00 ft / 4.27 m aft of break)
- Quarterdeck (10 %): 14.00 ft / 4.27 m
- Stern: 14.00 ft / 4.27 m
- Average freeboard: 17.44 ft / 5.32 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 201.0 %
- Above water (accommodation/working, high = better): 118.0 %
Waterplane Area: 9,576 Square feet or 890 Square metres
Displacement factor (Displacement / loading): 60 %
Structure weight / hull surface area: 35 lbs/sq ft or 170 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 2.16
- Overall: 0.57
Hull space for machinery, storage, compartmentation is extremely poor
Room for accommodation and workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather


Costs per Hull:-
Built in Nordmark - 2243t
Licence fee (for Construction in Persian Yard) - 150t

Enter ship name, Enter country Enter ship type laid down 1937

Displacement:
1,865 t light; 1,927 t standard; 2,043 t normal; 2,136 t full load

Dimensions: Length overall / water x beam x draught
405.22 ft / 393.70 ft x 36.42 ft x 12.47 ft (normal load)
123.51 m / 120.00 m x 11.10 m x 3.80 m

Armament:
3 - 4.92" / 125 mm guns in single mounts, 59.59lbs / 27.03kg shells, 1937 Model
Breech loading guns in deck mounts with hoists
on centreline ends, majority aft, 1 raised mount aft
4 - 1.38" / 35.0 mm guns (2x2 guns), 1.31lbs / 0.59kg shells, 1937 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
8 - 0.59" / 15.0 mm guns (2x4 guns), 0.10lbs / 0.05kg shells, 1937 Model
Machine guns in deck mounts
on centreline, evenly spread, all raised mounts
Weight of broadside 185 lbs / 84 kg
Shells per gun, main battery: 200
4 - 24.0" / 610 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.98" / 25 mm - 0.98" / 25 mm
2nd: 0.79" / 20 mm - -
3rd: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 60,000 shp / 44,760 Kw = 37.85 kts
Range 2,500nm at 15.00 kts (Bunkerage = 209 tons)

Complement:
151 - 197

Cost:
£1.378 million / $5.511 million

Distribution of weights at normal displacement:
Armament: 23 tons, 1.1 %
Armour: 10 tons, 0.5 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 10 tons, 0.5 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 1,199 tons, 58.7 %
Hull, fittings & equipment: 603 tons, 29.5 %
Fuel, ammunition & stores: 178 tons, 8.7 %
Miscellaneous weights: 30 tons, 1.5 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
449 lbs / 203 Kg = 7.5 x 4.9 " / 125 mm shells or 0.3 torpedoes
Stability (Unstable if below 1.00): 1.36
Metacentric height 1.9 ft / 0.6 m
Roll period: 11.1 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.20
Seaboat quality (Average = 1.00): 0.77

Hull form characteristics:
Hull has raised forecastle, rise forward of midbreak
and transom stern
Block coefficient: 0.400
Length to Beam Ratio: 10.81 : 1
'Natural speed' for length: 22.80 kts
Power going to wave formation at top speed: 69 %
Trim (Max stability = 0, Max steadiness = 100): 65
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 3.28 ft / 1.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.64 ft / 6.90 m
- Forecastle (20 %): 22.64 ft / 6.90 m (17.72 ft / 5.40 m aft of break)
- Mid (50 %): 17.72 ft / 5.40 m (9.84 ft / 3.00 m aft of break)
- Quarterdeck (15 %): 9.84 ft / 3.00 m
- Stern: 9.84 ft / 3.00 m
- Average freeboard: 14.76 ft / 4.50 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 199.8 %
- Above water (accommodation/working, high = better): 116.6 %
Waterplane Area: 9,159 Square feet or 851 Square metres
Displacement factor (Displacement / loading): 58 %
Structure weight / hull surface area: 36 lbs/sq ft or 176 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.40
- Overall: 0.55
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is adequate
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Like the Kaveh this specification seems to be overambitious.

You could get this in a couple of years. You just have to give up gun firepower, survivability, seakeeping, and range.

Oh, and if you actually run at 40kts for any period of time, you might not have the fuel to get back to port. A full fuel tank will take her 70 nm at full speed...

Enter ship name, Enter country Enter ship type laid down 1938

Displacement:
1,978 t light; 2,022 t standard; 2,075 t normal; 2,118 t full load

Dimensions: Length overall / water x beam x draught
406.96 ft / 393.70 ft x 34.28 ft x 13.45 ft (normal load)
124.04 m / 120.00 m x 10.45 m x 4.10 m

Armament:
1 - 3.94" / 100 mm guns in single mounts, 37.48lbs / 17.00kg shells, 1938 Model
Quick firing gun in deck mount
on centreline forward
4 - 1.46" / 37.0 mm guns (1x4 guns), 1.55lbs / 0.70kg shells, 1938 Model
Anti-aircraft guns in a deck mount with hoist
on centreline aft, all raised guns - superfiring
8 - 0.55" / 14.0 mm guns (4x2 guns), 0.08lbs / 0.04kg shells, 1938 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 44 lbs / 20 kg
Shells per gun, main battery: 100
4 - 25.6" / 650 mm above water torpedoes

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 76,360 shp / 56,965 Kw = 40.00 kts
Range 1,000nm at 15.00 kts
Bunker at max displacement = 96 tons

Complement:
153 - 199

Cost:
£1.500 million / $5.999 million

Distribution of weights at normal displacement:
Armament: 5 tons, 0.2 %
Machinery: 1,378 tons, 66.4 %
Hull, fittings & equipment: 583 tons, 28.1 %
Fuel, ammunition & stores: 97 tons, 4.7 %
Miscellaneous weights: 12 tons, 0.6 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
384 lbs / 174 Kg = 12.6 x 3.9 " / 100 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.41
Metacentric height 1.8 ft / 0.6 m
Roll period: 10.6 seconds
Steadiness - As gun platform (Average = 50 %): 51 %
- Recoil effect (Restricted arc if above 1.00): 0.03
Seaboat quality (Average = 1.00): 0.72

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.400
Length to Beam Ratio: 11.48 : 1
'Natural speed' for length: 22.69 kts
Power going to wave formation at top speed: 71 %
Trim (Max stability = 0, Max steadiness = 100): 71
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 22.97 ft / 7.00 m
- Forecastle (20 %): 18.04 ft / 5.50 m
- Mid (50 %): 18.04 ft / 5.50 m (9.84 ft / 3.00 m aft of break)
- Quarterdeck (15 %): 9.84 ft / 3.00 m
- Stern: 10.83 ft / 3.30 m
- Average freeboard: 14.41 ft / 4.39 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 216.4 %
- Above water (accommodation/working, high = better): 101.9 %
Waterplane Area: 8,623 Square feet or 801 Square metres
Displacement factor (Displacement / loading): 49 %
Structure weight / hull surface area: 35 lbs/sq ft or 171 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 1.53
- Overall: 0.56
Hull space for machinery, storage, compartmentation is extremely poor
Room for accommodation and workspaces is adequate
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Despite the fact that none of the proposals meet the specifications Persia has ordered one of the Nordmark design
to be called the Vendidad (Given against demons) Class and five German S-Boote 1935