Habsburg GTB 1909

[Borys]

Ahoj!

I hope to build these for service in the Mediterranean. They look pretty much like the OTL GTB 1913. The two raised mounts - one is on the forecastle, the other is on a platform which allows the twin tubes to swing under it.
This ship is dervied from a previous design by the Danubius-Howaldswerke at Fiume. The previous design is coal fired and maybe will be built for the colonies. The difference is that I have oil in the Metrople, but not in the colonies.


GTB 1909, Habsburgs Big Torpedo Boat laid down 1909

Displacement:
   750 t light; 781 t standard; 829 t normal; 868 t full load

Dimensions: Length overall / water x beam x draught
   280,00 ft / 280,00 ft x 27,00 ft x 8,00 ft (normal load)
   85,34 m / 85,34 m x 8,23 m  x 2,44 m

Armament:
      3 - 4,00" / 102 mm guns in single mounts, 35,00lbs / 15,88kg shells, 1909 Model
     Quick firing guns in deck mounts
     on centreline ends, majority aft, 2 raised mounts - superfiring
      2 - 0,43" / 11,0 mm guns in single mounts, 0,04lbs / 0,02kg shells, 1909 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 105 lbs / 48 kg
   Shells per gun, main battery: 250
   4 - 20,0" / 508 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 19 437 shp / 14 500 Kw = 30,00 kts
   Range 1 500nm at 12,00 kts
   Bunker at max displacement = 87 tons

Complement:
   76 - 100

Cost:
   £0,099 million / $0,396 million

Distribution of weights at normal displacement:
   Armament: 12 tons, 1,4%
   Machinery: 447 tons, 53,9%
   Hull, fittings & equipment: 276 tons, 33,3%
   Fuel, ammunition & stores: 80 tons, 9,6%
   Miscellaneous weights: 15 tons, 1,8%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     248 lbs / 112 Kg = 7,7 x 4,0 " / 102 mm shells or 0,2 torpedoes
   Stability (Unstable if below 1.00): 1,35
   Metacentric height 1,2 ft / 0,4 m
   Roll period: 10,4 seconds
   Steadiness   - As gun platform (Average = 50 %): 61 %
         - Recoil effect (Restricted arc if above 1.00): 0,20
   Seaboat quality  (Average = 1.00): 1,21

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0,480
   Length to Beam Ratio: 10,37 : 1
   'Natural speed' for length: 16,73 kts
   Power going to wave formation at top speed: 69 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   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:      18,41 ft / 5,61 m
      - Forecastle (30%):   19,00 ft / 5,79 m (11,71 ft / 3,57 m aft of break)
      - Mid (50%):      11,71 ft / 3,57 m
      - Quarterdeck (15%):   11,71 ft / 3,57 m
      - Stern:      11,71 ft / 3,57 m
      - Average freeboard:   13,83 ft / 4,21 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 187,7%
      - Above water (accommodation/working, high = better): 97,2%
   Waterplane Area: 4 947 Square feet or 460 Square metres
   Displacement factor (Displacement / loading): 44%
   Structure weight / hull surface area: 25 lbs/sq ft or 124 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,51
      - Longitudinal: 3,05
      - Overall: 0,60
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate
   Good seaboat, rides out heavy weather easily

[Borys]

Colonial Version

GTB 1909, Habsburgs Colonial Big Torpedo Boat laid down 1909

Displacement:
   733 t light; 766 t standard; 829 t normal; 880 t full load

Dimensions: Length overall / water x beam x draught
   280,00 ft / 280,00 ft x 27,00 ft x 8,00 ft (normal load)
   85,34 m / 85,34 m x 8,23 m  x 2,44 m

Armament:
      2 - 4,00" / 102 mm guns in single mounts, 35,00lbs / 15,88kg shells, 1909 Model
     Quick firing guns in deck mounts
     on centreline ends, evenly spread, all raised mounts - superfiring
      4 - 3,00" / 76,2 mm guns in single mounts, 13,50lbs / 6,12kg shells, 1909 Model
     Breech loading guns in deck mounts
     on side, all amidships
      2 - 0,43" / 11,0 mm guns in single mounts, 0,04lbs / 0,02kg shells, 1909 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 124 lbs / 56 kg
   Shells per gun, main battery: 200
   4 - 20,0" / 508 mm above water torpedoes

Machinery:
   Coal and oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 16 801 shp / 12 533 Kw = 29,00 kts
   Range 1 500nm at 12,00 kts
   Bunker at max displacement = 115 tons (90% coal)

Complement:
   76 - 100

Cost:
   £0,099 million / $0,397 million

Distribution of weights at normal displacement:
   Armament: 15 tons, 1,8%
   Machinery: 437 tons, 52,6%
   Hull, fittings & equipment: 267 tons, 32,2%
   Fuel, ammunition & stores: 96 tons, 11,6%
   Miscellaneous weights: 15 tons, 1,8%

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     249 lbs / 113 Kg = 7,8 x 4,0 " / 102 mm shells or 0,2 torpedoes
   Stability (Unstable if below 1.00): 1,37
   Metacentric height 1,2 ft / 0,4 m
   Roll period: 10,3 seconds
   Steadiness   - As gun platform (Average = 50 %): 67 %
         - Recoil effect (Restricted arc if above 1.00): 0,24
   Seaboat quality  (Average = 1.00): 1,35

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0,480
   Length to Beam Ratio: 10,37 : 1
   'Natural speed' for length: 16,73 kts
   Power going to wave formation at top speed: 67 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   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:      18,41 ft / 5,61 m
      - Forecastle (30%):   19,00 ft / 5,79 m (11,71 ft / 3,57 m aft of break)
      - Mid (50%):      11,71 ft / 3,57 m
      - Quarterdeck (15%):   11,71 ft / 3,57 m
      - Stern:      11,71 ft / 3,57 m
      - Average freeboard:   13,83 ft / 4,21 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 186,2%
      - Above water (accommodation/working, high = better): 97,2%
   Waterplane Area: 4 947 Square feet or 460 Square metres
   Displacement factor (Displacement / loading): 46%
   Structure weight / hull surface area: 25 lbs/sq ft or 120 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 2,95
      - Overall: 0,59
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate
   Good seaboat, rides out heavy weather easily

[Korpen]

Unless you intend them as purely local defence ships, I think a bit more range would be nice, 1500nm @12 kts is after all only ~500nm @18kts.
But adding range will hurt the speed of course, so I can see the point of giving them very short legs.
Quite nice ships otherwise :)

[Borys]

Ahoj!
Yes, Torpedo Boats are for local defence - Adriatic, Sicilian Straits, etc.

Borys

[Korpen]

Ahoj!
Yes, Torpedo Boats are for local defence - Adriatic, Sicilian Straits, etc.

Borys

But short legs and long transit time's forces you to have more ships for the same job, as it is hard to shift them rapidly from one area to another.

[Borys]

Ahoj!
Not to be moved about.
5 Flotillas planned:
1 - Pola/Kottor
2 - Malta
3 - Pola/Kottor
4 - Catanduanes
5 - Desterro/Paranagua

A potential 6th
6 - Malta/Alhucema


Or maybe I will go for 500ton TBs, and build more 2400 ton Scouts?

Borys

[P3D]

If range is not a big issue, I'd go with an 500t design (and you could afford to build more), even if speed won't be faster than 27-28kts (they'd operate with the scouts acting as flotilla leaders). Similar to the policy the Swiss are following.

[Korpen]

If range is not a big issue, I'd go with an 500t design (and you could afford to build more), even if speed won't be faster than 27-28kts (they'd operate with the scouts acting as flotilla leaders). Similar to the policy the Swiss are following.

More ships is probably a good idea considered the average survival time for a TB in action so far...

[Borys]

Hmm ... fooled around with SS

Enter ship name, Enter country Enter ship type laid down 1909

Displacement:
   480 t light; 494 t standard; 524 t normal; 549 t full load

Dimensions: Length overall / water x beam x draught
   228,00 ft / 228,00 ft x 18,00 ft x 7,00 ft (normal load)
   69,49 m / 69,49 m x 5,49 m  x 2,13 m

Armament:
      2 - 3,00" / 76,2 mm guns in single mounts, 13,50lbs / 6,12kg shells, 1909 Model
     Quick firing guns in deck mounts
     on centreline ends, evenly spread, all raised mounts
      2 - 0,43" / 11,0 mm guns in single mounts, 0,04lbs / 0,02kg shells, 1909 Model
     Machine guns in deck mounts
     on side, evenly spread
   Weight of broadside 27 lbs / 12 kg
   Shells per gun, main battery: 250
   4 - 2,0" / 50,8 mm above water torpedoes

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 14 967 shp / 11 166 Kw = 29,00 kts
   Range 1 200nm at 12,00 kts
   Bunker at max displacement = 54 tons

Complement:
   54 - 71

Cost:
   £0,060 million / $0,239 million

Distribution of weights at normal displacement:
   Armament: 3 tons, 0,6%
   Machinery: 287 tons, 54,7%
   Hull, fittings & equipment: 180 tons, 34,2%
   Fuel, ammunition & stores: 44 tons, 8,5%
   Miscellaneous weights: 10 tons, 1,9%
the four tubes and their fish

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     157 lbs / 71 Kg = 11,6 x 3,0 " / 76 mm shells or 0,2 torpedoes
   Stability (Unstable if below 1.00): 1,17
   Metacentric height 0,5 ft / 0,2 m
   Roll period: 10,6 seconds
   Steadiness   - As gun platform (Average = 50 %): 53 %
         - Recoil effect (Restricted arc if above 1.00): 0,22
   Seaboat quality  (Average = 1.00): 1,06

Hull form characteristics:
   Hull has raised forecastle
   Block coefficient: 0,639
   Length to Beam Ratio: 12,67 : 1
   'Natural speed' for length: 15,10 kts
   Power going to wave formation at top speed: 73 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   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:      16,61 ft / 5,06 m
      - Forecastle (20%):   18,00 ft / 5,49 m (10,57 ft / 3,22 m aft of break)
      - Mid (50%):      10,57 ft / 3,22 m
      - Quarterdeck (15%):   10,57 ft / 3,22 m
      - Stern:      10,57 ft / 3,22 m
      - Average freeboard:   11,94 ft / 3,64 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 184,0%
      - Above water (accommodation/working, high = better): 115,3%
   Waterplane Area: 3 112 Square feet or 289 Square metres
   Displacement factor (Displacement / loading): 38%
   Structure weight / hull surface area: 21 lbs/sq ft or 102 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,53
      - Longitudinal: 5,26
      - Overall: 0,67
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate

[P3D]

I'd try to put two 4" guns on the design. You don't really have displacement restrictions. And some extra beam. L/B=12.67:1 is a bit on the high side.

[Borys]

Adding 3 feet of beam, and a lower oefficient produce a nice 500 ton vessel. I won't put 4 inchers on it is it seems wrong to have such big guns on such a smalll and fast vessel.

My limitation is lenght - I have few type 1 slips, and quite a few Type 0 ones.

Borys

[P3D]

Then put 4x3" on them.