WesWorld

TB-1, Atlantean Torpedo boat laid down 1930

Displacement:
581 t light; 600 t standard; 662 t normal; 712 t full load

Dimensions: Length overall / water x beam x draught
274.78 ft / 265.50 ft x 22.50 ft x 9.70 ft (normal load)
83.75 m / 80.92 m x 6.86 m x 2.96 m

Armament:
4 - 3.00" / 76.2 mm guns (2x2 guns), 13.50lbs / 6.12kg shells, 1930 Model
Dual purpose guns in deck mounts
on centreline ends, evenly spread
2 - 1.57" / 39.9 mm guns (1x2 guns), 1.93lbs / 0.88kg shells, 1930 Model
Anti-aircraft guns in deck mount
on side amidships, all raised guns
8 - 0.79" / 20.1 mm guns (4x2 guns), 0.25lbs / 0.11kg shells, 1930 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1930 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 60 lbs / 27 kg
Shells per gun, main battery: 160
6 - 21.0" / 533.4 mm above water torpedoes

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 20,500 shp / 15,293 Kw = 33.05 kts
Range 2,500nm at 15.00 kts
Bunker at max displacement = 112 tons

Complement:
64 - 84

Cost:
£0.308 million / $1.234 million

Distribution of weights at normal displacement:
Armament: 8 tons, 1.1 %
Machinery: 336 tons, 50.8 %
Hull, fittings & equipment: 197 tons, 29.8 %
Fuel, ammunition & stores: 81 tons, 12.3 %
Miscellaneous weights: 40 tons, 6.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
159 lbs / 72 Kg = 11.8 x 3.0 " / 76 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.07
Metacentric height 0.6 ft / 0.2 m
Roll period: 12.2 seconds
Steadiness - As gun platform (Average = 50 %): 60 %
- Recoil effect (Restricted arc if above 1.00): 0.23
Seaboat quality (Average = 1.00): 1.05

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.400
Length to Beam Ratio: 11.80 : 1
'Natural speed' for length: 18.60 kts
Power going to wave formation at top speed: 70 %
Trim (Max stability = 0, Max steadiness = 100): 57
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 2.00 ft / 0.61 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 20.00 ft / 6.10 m
- Forecastle (20 %): 16.00 ft / 4.88 m
- Mid (50 %): 16.00 ft / 4.88 m (8.00 ft / 2.44 m aft of break)
- Quarterdeck (15 %): 8.00 ft / 2.44 m
- Stern: 8.00 ft / 2.44 m
- Average freeboard: 12.32 ft / 3.76 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 179.4 %
- Above water (accommodation/working, high = better): 40.9 %
Waterplane Area: 3,816 Square feet or 355 Square metres
Displacement factor (Displacement / loading): 49 %
Structure weight / hull surface area: 21 lbs/sq ft or 101 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.42
- Longitudinal: 3.21
- Overall: 0.51
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is extremely poor

Looks good even though I´m not sure if it isn´t too small for Mid and North Atlantic use.

I also like to propose increase shell number by decreasing misc weight.

Are there two torpedo banks? How are they arrange given the ships short hull but otherwise heavy firepower?

The Torpedos are indeed in two banks, fore and aft of the second funnel (yes two funnels). The 20mm guns are abreast the funnels and the 40mm is superimposed over the aft turret. There are two lifeboats abreast the aft superstructure.

These ships are intended to work in the Caribbean and Tuarid sea's in order to free up the older DD's for other regions.

Another version as per Hoos suggestions.

TB-1, Atlantean Torpedo boat laid down 1930

Displacement:
580 t light; 600 t standard; 662 t normal; 712 t full load

Dimensions: Length overall / water x beam x draught
274.78 ft / 265.50 ft x 22.50 ft x 9.70 ft (normal load)
83.75 m / 80.92 m x 6.86 m x 2.96 m

Armament:
4 - 3.00" / 76.2 mm guns (2x2 guns), 13.50lbs / 6.12kg shells, 1930 Model
Dual purpose guns in deck mounts
on centreline ends, evenly spread
2 - 1.57" / 39.9 mm guns (1x2 guns), 1.93lbs / 0.88kg shells, 1930 Model
Anti-aircraft guns in deck mount
on side amidships, all raised guns
8 - 0.79" / 20.1 mm guns (4x2 guns), 0.25lbs / 0.11kg shells, 1930 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1930 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 60 lbs / 27 kg
Shells per gun, main battery: 200
6 - 21.0" / 533.4 mm above water torpedoes

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 22,000 shp / 16,412 Kw = 33.61 kts
Range 2,500nm at 15.00 kts
Bunker at max displacement = 112 tons

Complement:
64 - 84

Cost:
£0.313 million / $1.254 million

Distribution of weights at normal displacement:
Armament: 8 tons, 1.1 %
Machinery: 345 tons, 52.1 %
Hull, fittings & equipment: 207 tons, 31.2 %
Fuel, ammunition & stores: 83 tons, 12.5 %
Miscellaneous weights: 20 tons, 3.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
169 lbs / 77 Kg = 12.5 x 3.0 " / 76 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.16
Metacentric height 0.7 ft / 0.2 m
Roll period: 11.3 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.20
Seaboat quality (Average = 1.00): 1.00

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.400
Length to Beam Ratio: 11.80 : 1
'Natural speed' for length: 18.60 kts
Power going to wave formation at top speed: 71 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 2.00 ft / 0.61 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 20.00 ft / 6.10 m
- Forecastle (20 %): 16.00 ft / 4.88 m
- Mid (50 %): 16.00 ft / 4.88 m (8.00 ft / 2.44 m aft of break)
- Quarterdeck (15 %): 8.00 ft / 2.44 m
- Stern: 8.00 ft / 2.44 m
- Average freeboard: 12.32 ft / 3.76 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 180.7 %
- Above water (accommodation/working, high = better): 40.9 %
Waterplane Area: 3,816 Square feet or 355 Square metres
Displacement factor (Displacement / loading): 47 %
Structure weight / hull surface area: 22 lbs/sq ft or 106 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.43
- Longitudinal: 3.37
- Overall: 0.53
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is extremely poor

Both designs still have a cross-sectional HS of below 0,5.....

They'll require Class 1 slips and docks too. It could be a real headache maintaining them and your destroyers as well, if you build them in quantity.

Not to mention that Hoo, when he notices the l:b ratio, will be jumping up and down.

Well, for a small and fast TB such a L:B ratio is kind of reasonable. It´s on the edge, methinks, but still within the frame we set for our designs... There´s also historical precedence for vessels like these, I guess. Wes?

Oddly enough the historical Spica class TB's are the type of vessel I'm looking for, something with reasonable offensive and defencive capability's.

I'm assuming you mean the cross sectional hull strength needs to be over 0.5?

As for the infrastructure burden its the very reason I've been building more S-1's and S-0's.

Quoted

I'm assumeing you mean the cross sectional hull strength needs to be over 0.5?

Naturally, Mr. Wilson.

Quoted

As for the infrastructure burden its the very reason I've been building more S-1's and S-0's.

You'll need them. I'm currently building a bunch of small submarines and everything is in use.

Quoted

Not to mention that Hoo, when he notices the l:b ratio, will be jumping up and down.

Checking Japan's Encyclopedia section, I actually spotted l:b ratios of 14.75 and 16.86 among all my stuff...
... so he might still be jumping up and down when he reads this.

... unless he reads this camouflaged bit of test which indicates that those l:b ratios are actually of the newest 21 and 24 inch torpedoes.
:-)

Back to the drawing board!

Version 1.4

TB-1, Atlantean Torpedo boat laid down 1930

Displacement:
601 t light; 621 t standard; 653 t normal; 677 t full load

Dimensions: Length overall / water x beam x draught
274.64 ft / 265.00 ft x 22.80 ft x 9.00 ft (normal load)
83.71 m / 80.77 m x 6.95 m x 2.74 m

Armament:
4 - 3.00" / 76.2 mm guns (2x2 guns), 13.50lbs / 6.12kg shells, 1930 Model
Dual purpose guns in deck mounts
on centreline ends, evenly spread
2 - 1.57" / 39.9 mm guns (1x2 guns), 1.93lbs / 0.88kg shells, 1930 Model
Anti-aircraft guns in deck mount
on side amidships, all raised guns
8 - 0.79" / 20.1 mm guns (4x2 guns), 0.25lbs / 0.11kg shells, 1930 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1930 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 60 lbs / 27 kg
Shells per gun, main battery: 200
6 - 21.0" / 533.4 mm above water torpedoes

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 22,160 shp / 16,532 Kw = 33.61 kts
Range 2,000nm at 12.00 kts
Bunker at max displacement = 56 tons

Complement:
63 - 83

Cost:
£0.314 million / $1.256 million

Distribution of weights at normal displacement:
Armament: 8 tons, 1.2 %
Machinery: 341 tons, 52.2 %
Hull, fittings & equipment: 233 tons, 35.7 %
Fuel, ammunition & stores: 51 tons, 7.9 %
Miscellaneous weights: 20 tons, 3.1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
187 lbs / 85 Kg = 13.8 x 3.0 " / 76 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.09
Metacentric height 0.6 ft / 0.2 m
Roll period: 12.0 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.20
Seaboat quality (Average = 1.00): 0.88

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.420
Length to Beam Ratio: 11.62 : 1
'Natural speed' for length: 18.55 kts
Power going to wave formation at top speed: 72 %
Trim (Max stability = 0, Max steadiness = 100): 56
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 2.00 ft / 0.61 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.00 ft / 6.40 m
- Forecastle (20 %): 15.75 ft / 4.80 m
- Mid (50 %): 15.75 ft / 4.80 m (7.75 ft / 2.36 m aft of break)
- Quarterdeck (15 %): 7.75 ft / 2.36 m
- Stern: 7.75 ft / 2.36 m
- Average freeboard: 12.17 ft / 3.71 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 181.1 %
- Above water (accommodation/working, high = better): 42.7 %
Waterplane Area: 3,910 Square feet or 363 Square metres
Displacement factor (Displacement / loading): 46 %
Structure weight / hull surface area: 25 lbs/sq ft or 122 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 3.50
- Overall: 0.61
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is extremely poor
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Version 1.5

TB-1, Atlantean Torpedo boat laid down 1931

Displacement:
599 t light; 619 t standard; 650 t normal; 675 t full load

Dimensions: Length overall / water x beam x draught
273.64 ft / 264.00 ft x 22.80 ft x 9.00 ft (normal load)
83.41 m / 80.47 m x 6.95 m x 2.74 m

Armament:
4 - 3.00" / 76.2 mm guns (2x2 guns), 13.50lbs / 6.12kg shells, 1931 Model
Dual purpose guns in deck mounts
on centreline ends, evenly spread
2 - 1.57" / 39.9 mm guns (1x2 guns), 1.93lbs / 0.88kg shells, 1931 Model
Anti-aircraft guns in deck mount
on side amidships, all raised guns
6 - 0.79" / 20.1 mm guns in single mounts, 0.25lbs / 0.11kg shells, 1931 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1931 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 60 lbs / 27 kg
Shells per gun, main battery: 200
6 - 21.0" / 533.4 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 22,161 shp / 16,532 Kw = 33.61 kts
Range 2,000nm at 12.00 kts
Bunker at max displacement = 55 tons

Complement:
63 - 83

Cost:
£0.325 million / $1.301 million

Distribution of weights at normal displacement:
Armament: 7 tons, 1.1 %
Armour: 4 tons, 0.6 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 4 tons, 0.6 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 338 tons, 52.0 %
Hull, fittings & equipment: 230 tons, 35.3 %
Fuel, ammunition & stores: 51 tons, 7.8 %
Miscellaneous weights: 20 tons, 3.1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
185 lbs / 84 Kg = 13.7 x 3.0 " / 76 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 0.6 ft / 0.2 m
Roll period: 12.0 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.20
Seaboat quality (Average = 1.00): 0.88

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.420
Length to Beam Ratio: 11.58 : 1
'Natural speed' for length: 18.52 kts
Power going to wave formation at top speed: 72 %
Trim (Max stability = 0, Max steadiness = 100): 57
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 2.00 ft / 0.61 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.00 ft / 6.40 m
- Forecastle (20 %): 15.75 ft / 4.80 m
- Mid (50 %): 15.75 ft / 4.80 m (7.75 ft / 2.36 m aft of break)
- Quarterdeck (15 %): 7.75 ft / 2.36 m
- Stern: 7.75 ft / 2.36 m
- Average freeboard: 12.17 ft / 3.71 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 180.3 %
- Above water (accommodation/working, high = better): 42.2 %
Waterplane Area: 3,896 Square feet or 362 Square metres
Displacement factor (Displacement / loading): 46 %
Structure weight / hull surface area: 25 lbs/sq ft or 121 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 3.49
- Overall: 0.60
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is extremely poor
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Quoted

185 lbs / 84 Kg = 13.7 x 3.0 " / 76 mm shells or 0.2 torpedoes

I'll demonstrate in a couple of days time why this could be the problem with 600 ton torpedo boats...

Cheers,

Could you provide a breif introduction as to why this is a problem? Keep in mind these ships (at least in the case of Atlantis) are to be used in non-frontline arena's in order to free up the larger DD's.

A Tiger tank is more survivable than one of these...

I think you could make a better destroyer substitute with 1200 tons, 24knots and 4-5" guns than two of these ships. All 3" guns are going to do is give away your position. WW1 showed that a DD is more likely to use guns than torpedoes and destroyers spend a lot more time under 20 knots that over 30. If you are in coastal waters what's wrong with MTB's?

Cheers,

Quoted

Originally posted by alt_naval
A Tiger tank is more survivable than one of these...

Hell if we used a Sherman as the benchmark I'm sure we would get better results :-P

Even so I wouldn't expect these ships to take much of a beating anyway, they are more expendable than 1,200/2,000 ton DD's.

Quoted

Originally posted by alt_naval I think you could make a better destroyer substitute with 1200 tons, 24knots and 4-5" guns than two of these ships.

Absolutely, allthough they cannot be armed with torpedo's IIRC due to CT rules. I do have plans to build some slower DE's.

Quoted

Originally posted by alt_naval All 3" guns are going to do is give away your position. WW1 showed that a DD is more likely to use guns than torpedoes and destroyers spend a lot more time under 20 knots than over 30.

The 3" guns primary role is defence against smaller vessels and aircraft.

Quoted

Originally posted by alt_naval If you are in coastal waters what's wrong with MTB's?

Nothing at all, in fact I'm working on increasing my MTB numbers to 80/120 MTB/CMB's by mid 1931

The problem is that the 3" gun is largely ineffective against aircraft and ships. The shell just isn't big enough. Against aircraft you would have to explode the shell very close, in effect a direct hit to stand a chance of destroying it.

In that case I'd be tempted to ship 2x4.5" for surface work and add some more 40mm for AA.

Hows this?

TB-1, Atlantean Torpedo boat laid down 1931

Displacement:
602 t light; 627 t standard; 653 t normal; 674 t full load

Dimensions: Length overall / water x beam x draught
272.64 ft / 263.00 ft x 23.00 ft x 9.00 ft (normal load)
83.10 m / 80.16 m x 7.01 m x 2.74 m

Armament:
2 - 4.50" / 114 mm guns in single mounts, 45.56lbs / 20.67kg shells, 1931 Model
Dual purpose guns in deck mounts
on centreline ends, evenly spread
4 - 1.57" / 39.9 mm guns (2x2 guns), 1.93lbs / 0.88kg shells, 1931 Model
Anti-aircraft guns in deck mounts
on centreline, evenly spread, 1 raised mount
6 - 0.79" / 20.1 mm guns in single mounts, 0.25lbs / 0.11kg shells, 1931 Model
Anti-aircraft guns in deck mounts
on side, evenly spread
4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1931 Model
Machine guns in deck mounts
on side, evenly spread
Weight of broadside 101 lbs / 46 kg
Shells per gun, main battery: 200
6 - 21.0" / 533.4 mm above water torpedoes

Armour:
- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.79" / 20 mm - -

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 22,000 shp / 16,412 Kw = 33.51 kts
Range 1,000nm at 15.00 kts
Bunker at max displacement = 47 tons

Complement:
63 - 83

Cost:
£0.340 million / $1.361 million

Distribution of weights at normal displacement:
Armament: 13 tons, 1.9 %
Armour: 4 tons, 0.6 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 4 tons, 0.6 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 0 tons, 0.0 %
Machinery: 331 tons, 50.6 %
Hull, fittings & equipment: 235 tons, 35.9 %
Fuel, ammunition & stores: 51 tons, 7.8 %
Miscellaneous weights: 20 tons, 3.1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
180 lbs / 82 Kg = 3.9 x 4.5 " / 114 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.04
Metacentric height 0.6 ft / 0.2 m
Roll period: 12.5 seconds
Steadiness - As gun platform (Average = 50 %): 55 %
- Recoil effect (Restricted arc if above 1.00): 0.34
Seaboat quality (Average = 1.00): 0.87

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.420
Length to Beam Ratio: 11.43 : 1
'Natural speed' for length: 18.50 kts
Power going to wave formation at top speed: 72 %
Trim (Max stability = 0, Max steadiness = 100): 63
Bow angle (Positive = bow angles forward): 20.00 degrees
Stern overhang: 2.00 ft / 0.61 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 21.00 ft / 6.40 m
- Forecastle (20 %): 15.75 ft / 4.80 m
- Mid (50 %): 15.75 ft / 4.80 m (7.75 ft / 2.36 m aft of break)
- Quarterdeck (15 %): 7.75 ft / 2.36 m
- Stern: 7.75 ft / 2.36 m
- Average freeboard: 12.17 ft / 3.71 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 182.1 %
- Above water (accommodation/working, high = better): 42.9 %
Waterplane Area: 3,915 Square feet or 364 Square metres
Displacement factor (Displacement / loading): 45 %
Structure weight / hull surface area: 25 lbs/sq ft or 124 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 3.54
- Overall: 0.60
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is extremely poor
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather