Iberia Torpedo Boat, 750t type

[miketr]

I am playing with what I can do with my new Destroyer Tech.  I decided to put the extra displacement into giving them a much larger gun punch.  Not sure their fast enough.  Also each mount a radio and have 1 set of reloads for their tubes.  Should I try for an even higher speed? 

The TB-1906 stats are...

500 tons, 28.5 knots, 3x1 47mm QF, 2x2 18" TT

****************************************
TB-1909, Iberia Torpedo Boat laid down 1909

Displacement:
   768 t light; 807 t standard; 881 t normal; 940 t full load

Dimensions: Length overall / water x beam x draught
   250.00 ft / 250.00 ft x 25.00 ft x 10.50 ft (normal load)
   76.20 m / 76.20 m x 7.62 m  x 3.20 m

Armament:
      2 - 4.92" / 125 mm guns in single mounts, 59.59lbs / 27.03kg shells, 1909 Model
     Breech loading guns in deck mounts
     on centreline ends, evenly spread
      2 - 1.97" / 50.0 mm guns in single mounts, 3.81lbs / 1.73kg shells, 1909 Model
     Quick firing guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 127 lbs / 58 kg
   Shells per gun, main battery: 300
   4 - 18.0" / 457.2 mm above water torpedoes

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

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 22,000 shp / 16,412 Kw = 30.11 kts
   Range 2,800nm at 10.00 kts
   Bunker at max displacement = 133 tons (67% coal)

Complement:
   80 - 105

Cost:
   £0.108 million / $0.433 million

Distribution of weights at normal displacement:
   Armament: 16 tons, 1.8 %
   Armour: 7 tons, 0.8 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 7 tons, 0.8 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 486 tons, 55.2 %
   Hull, fittings & equipment: 241 tons, 27.3 %
   Fuel, ammunition & stores: 113 tons, 12.8 %
   Miscellaneous weights: 18 tons, 2.0 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     185 lbs / 84 Kg = 3.1 x 4.9 " / 125 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.18
   Metacentric height 0.9 ft / 0.3 m
   Roll period: 11.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.30
   Seaboat quality  (Average = 1.00): 0.95

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.470
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 15.81 kts
   Power going to wave formation at top speed: 72 %
   Trim (Max stability = 0, Max steadiness = 100): 74
   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:      22.00 ft / 6.71 m
      - Forecastle (20 %):   17.00 ft / 5.18 m (11.07 ft / 3.37 m aft of break)
      - Mid (50 %):      11.07 ft / 3.37 m
      - Quarterdeck (15 %):   11.07 ft / 3.37 m
      - Stern:      11.07 ft / 3.37 m
      - Average freeboard:   12.66 ft / 3.86 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 195.3 %
      - Above water (accommodation/working, high = better): 72.2 %
   Waterplane Area: 4,054 Square feet or 377 Square metres
   Displacement factor (Displacement / loading): 39 %
   Structure weight / hull surface area: 26 lbs/sq ft or 125 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 3.27
      - Overall: 0.60
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Ship has slow, easy roll, a good, steady gun platform
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

One short wave radio, 8 torpedo's total 4 in tubes and 4 reloads

[Borys]

Ahoj!
Forget the 4,6" gun - you won hit anything with it 3-4 x3/3,5", or 2x4 inch +4x3 inch.
Borys

[miketr]

The 4.92" gun is unlikely to hit anything but if it does hit or close miss with HE it will do something.  A 3" or 3.5" will need multi hits.  If I ditch the 125mm guns its possible to fit the following weapons suit...

Three 105mm (one super), four 50mm QF weapons.   

Michael

[The Rock Doctor]

It's not a bad design, but it's not 750 t either.

I notice a lot of folks putting reloads onto destroyers - I wasn't aware of this being done historically at the time.

[miketr]

OK I slimped it down to 750 tons light displacement.  List another 100 miles of range and two 50mm guns.

Any other suggestions?

Michael

****************************************
TB-1909, Iberia Torpedo Boat laid down 1909

Displacement:
   750 t light; 783 t standard; 853 t normal; 909 t full load

Dimensions: Length overall / water x beam x draught
   250.00 ft / 250.00 ft x 25.00 ft x 10.50 ft (normal load)
   76.20 m / 76.20 m x 7.62 m  x 3.20 m

Armament:
      3 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1909 Model
     Breech loading guns in deck mounts
     on centreline ends, majority forward, 1 raised mount
      2 - 1.97" / 50.0 mm guns in single mounts, 3.81lbs / 1.73kg shells, 1909 Model
     Quick firing guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 114 lbs / 52 kg
   Shells per gun, main battery: 250
   4 - 18.0" / 457.2 mm above water torpedoes

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

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 21,000 shp / 15,666 Kw = 30.00 kts
   Range 2,700nm at 10.00 kts
   Bunker at max displacement = 126 tons (67% coal)

Complement:
   78 - 102

Cost:
   £0.104 million / $0.415 million

Distribution of weights at normal displacement:
   Armament: 14 tons, 1.7 %
   Armour: 9 tons, 1.0 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 9 tons, 1.0 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 468 tons, 54.9 %
   Hull, fittings & equipment: 241 tons, 28.2 %
   Fuel, ammunition & stores: 103 tons, 12.1 %
   Miscellaneous weights: 18 tons, 2.1 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     187 lbs / 85 Kg = 5.3 x 4.1 " / 105 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.18
   Metacentric height 0.9 ft / 0.3 m
   Roll period: 11.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.30
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.455
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 15.81 kts
   Power going to wave formation at top speed: 71 %
   Trim (Max stability = 0, Max steadiness = 100): 71
   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:      22.00 ft / 6.71 m
      - Forecastle (20 %):   18.00 ft / 5.49 m (11.07 ft / 3.37 m aft of break)
      - Mid (50 %):      11.07 ft / 3.37 m
      - Quarterdeck (15 %):   11.07 ft / 3.37 m
      - Stern:      11.07 ft / 3.37 m
      - Average freeboard:   12.78 ft / 3.89 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 192.8 %
      - Above water (accommodation/working, high = better): 73.2 %
   Waterplane Area: 4,003 Square feet or 372 Square metres
   Displacement factor (Displacement / loading): 39 %
   Structure weight / hull surface area: 26 lbs/sq ft or 125 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 3.43
      - Overall: 0.60
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Ship has slow, easy roll, a good, steady gun platform

Short range radio 10 tons and 8 torpedos, 4 in tube and 4 reloads

[miketr]

Layout...


B................50................................................
O......105......................18TT............18TT...105...105
W................50................................................


Torpedo's are in double mounts

[Borys]

Ahoj!
It was not unusual in this age to mount guns on same level (look at Novik and variants).
Is the "raised" 105mm the one on the forecastle?
Borys

[miketr]

B................50................................................
O......105......................18TT............18TT...105...105
W................50................................................
.......................................................^raised


As far as I know SS considers guns being raised from the deck they are mounted on.  All the samples with breaks in the deck line follow this.

Michael

[Borys]

Ahoj!
No, not the deck they are mounted on. Freeboard.
Quote from SS2 manual:

Above Freeboard:  This replaces the superfiring guns adjustment. Enter the number of barrels mounted on a deck above freeboard height or that are mounted on a raised barbettes or other platforms so they can fire over other guns. This affects the armour weight of full turrets, mounts with armoured barbettes or hoist protection and stability. Examples
•   HMS Dreadnought's forward turret is mounted one deck higher than the freeboard at that point to allow the 2 side mounted turrets to fire forward and still have reasonable freeboard at the forecastle. These 2 12" barrels are high – enter 2 in Above Freeboard.
•   HMS King George V (1939) has 3 turrets all mounted on the same deck at freeboard level. One turret is on a raised barbette to fire over another. This is a traditional superfiring mount. However this turret only has 2 guns whilst the rest have 4 each. Enter 2 in Above Freeboard.

IMO you have 2 raised mounts.
Borys

[Korpen]

B................50................................................
O......105......................18TT............18TT...105...105
W................50................................................
.......................................................^raised


As far as I know SS considers guns being raised from the deck they are mounted on.  All the samples with breaks in the deck line follow this.

Michael

Springsharp never place a gun on the forecastle (or quarterdeck), unless my memory has failed me totally.

[maddox]

 In theory you can have a gun on the bow or stern, just adjust the length of the forecastle and quarterdeck.

[miketr]

There is enough stability to handle two 105mm raised.

TB-1909, Iberia Torpedo Boat laid down 1909

Displacement:
   750 t light; 783 t standard; 853 t normal; 909 t full load

Dimensions: Length overall / water x beam x draught
   250.00 ft / 250.00 ft x 25.00 ft x 10.50 ft (normal load)
   76.20 m / 76.20 m x 7.62 m  x 3.20 m

Armament:
      3 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1909 Model
     Breech loading guns in deck mounts
     on centreline ends, majority aft, 2 raised mounts - superfiring
      2 - 1.97" / 50.0 mm guns in single mounts, 3.81lbs / 1.73kg shells, 1909 Model
     Quick firing guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
   Weight of broadside 114 lbs / 52 kg
   Shells per gun, main battery: 250
   4 - 18.0" / 457.2 mm above water torpedoes

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

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 21,000 shp / 15,666 Kw = 30.00 kts
   Range 2,700nm at 10.00 kts
   Bunker at max displacement = 126 tons (67% coal)

Complement:
   78 - 102

Cost:
   £0.104 million / $0.415 million

Distribution of weights at normal displacement:
   Armament: 14 tons, 1.7 %
   Armour: 9 tons, 1.0 %
      - Belts: 0 tons, 0.0 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 9 tons, 1.0 %
      - Armour Deck: 0 tons, 0.0 %
      - Conning Tower: 0 tons, 0.0 %
   Machinery: 468 tons, 54.9 %
   Hull, fittings & equipment: 241 tons, 28.2 %
   Fuel, ammunition & stores: 103 tons, 12.1 %
   Miscellaneous weights: 18 tons, 2.1 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     185 lbs / 84 Kg = 5.2 x 4.1 " / 105 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.17
   Metacentric height 0.8 ft / 0.3 m
   Roll period: 11.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0.32
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0.455
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 15.81 kts
   Power going to wave formation at top speed: 71 %
   Trim (Max stability = 0, Max steadiness = 100): 71
   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:      22.00 ft / 6.71 m
      - Forecastle (20 %):   18.00 ft / 5.49 m (11.07 ft / 3.37 m aft of break)
      - Mid (50 %):      11.07 ft / 3.37 m
      - Quarterdeck (15 %):   11.07 ft / 3.37 m
      - Stern:      11.07 ft / 3.37 m
      - Average freeboard:   12.78 ft / 3.89 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 192.8 %
      - Above water (accommodation/working, high = better): 73.2 %
   Waterplane Area: 4,003 Square feet or 372 Square metres
   Displacement factor (Displacement / loading): 39 %
   Structure weight / hull surface area: 26 lbs/sq ft or 125 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 3.40
      - Overall: 0.60
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is cramped
   Ship has slow, easy roll, a good, steady gun platform

Short range radio 10 tons and 8 torpedos, 4 in tube and 4 reloads