WesWorld

A little coastdefence ship for my swedish navy. site updated since last visited.

Dalarö, Sweden Coast defence ship laid down 1896

Displacement:
4 186 t light; 4 441 t standard; 4 500 t normal; 4 529 t full load
Loading submergence 395 tons/feet

Dimensions:
311,68 ft x 59,06 ft x 13,12 ft (normal load)
95,00 m x 18,00 m x 4,00 m

Armament:
2 - 10,83" / 275 mm guns (2 Main turrets x 1 guns)
6 - 6,00" / 152 mm guns
10 - 2,24" / 57 mm QF guns
QF guns mounted low & subject to being washed down in a seaway
4 - 0,79" / 20 mm guns
Weight of broadside 1 975 lbs / 896 kg
2 - 18,0" / 457,2 mm submerged torpedo tubes

Armour:
Belt 7,28" / 185 mm, upper belt 1,97" / 50 mm, end belts 1,97" / 50 mm
Belts cover 100 % of normal area
Main belt does not fully protect magazines and engineering spaces
Main turrets 7,28" / 185 mm, 2nd gun shields 1,97" / 50 mm
QF casemates 1,97" / 50 mm
Armour deck 1,97" / 50 mm, Conning tower 7,28" / 185 mm

Machinery:
Coal fired boilers, complex reciprocating steam engines,
Direct drive, 3 shafts, 4 958 ihp / 3 699 Kw = 16,00 kts
Range 1 000nm at 8,00 kts

Complement:
274 - 357

Cost:
£0,468 million / $1,870 million

Distribution of weights at normal displacement:
Armament: 247 tons, 5,5 %
Armour: 1 709 tons, 38,0 %
Belts: 822 tons, 18,3 %, Armament: 342 tons, 7,6 %, Armour Deck: 503 tons, 11,2 %
Conning Tower: 43 tons, 0,9 %, Torpedo bulkhead: 0 tons, 0,0 %
Machinery: 812 tons, 18,1 %
Hull, fittings & equipment: 1 418 tons, 31,5 %
Fuel, ammunition & stores: 314 tons, 7,0 %
Miscellaneous weights: 0 tons, 0,0 %

Metacentric height 3,3

Remarks:
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable and able to fight her guns in the heaviest weather

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1,24
Shellfire needed to sink: 3 832 lbs / 1 738 Kg = 6,0 x 10,8 " / 275 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 1,0
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 90 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0,67
Relative quality as seaboat: 1,80

Hull form characteristics:
Block coefficient: 0,652
Sharpness coefficient: 0,47
Hull speed coefficient 'M': 5,77
'Natural speed' for length: 17,65 kts
Power going to wave formation at top speed: 47 %
Trim: 50
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 105,1 %
Relative accommodation and working space: 157,6 %
(Average = 100%)
Displacement factor: 84 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0,63
(Structure weight / hull surface area: 74 lbs / square foot or 361 Kg / square metre)
Relative longitudinal hull strength: 1,76
(for 16,40 ft / 5,00 m average freeboard, freeboard adjustment 3,50 ft)
Relative composite hull strength: 0,69

Nice looking vessel. You're not worried with the hull strength of 0,69 ? (same with the Pojhama)
The picture on the site of this vessel is nice too.

Walter

That is the question, springsharp says that it is only suitable for small and fast ships. These ships are ment to operate in the baltic which seldom(never) offers a wavehight over 6m and mostly in the archipelago where the strain will be even less due to hardly any waves.

I know a ship of similar size(the Giötha, even smaller) crossed the northsea in a storm i the 1880s with waves up to 10-12m and made it without major problem.

For a DD is such a low hull strength no problem, but can you go with it on a small coastal dreadnought?

because of problems in the model Spring* uses. Unless you can show us a similar historical vessel. Generally the model breaks down for small vessels, more so for small fast vessels. Still, I'd be leery. This hasn't really been explored for such small ships and such heavy armament before (that I am aware at least), so I am open to persuasion.

Nice design and I love the drawing. Can I have one for my keychain please? It's downright cuddly ... :-)

Bernhard

A similar vessel is the swedish Oden-class and Göta-classes.(not teatured at warships1).

Oden
1896
3700 tons

Dimension
86x15x5m

armour
side 243mm, turret 200mm, deck 25mm

guns
2x1 254mm
4x 120mm

speed 15, range 2500@10knots


Göta
1889
3700 tons

dimension
82x15x5m

armour
side 293mm, turret 293mm, deck 25mm

guns
1x2 254mm
4x 152mm

speed 16, range 2500@10knots

The freeboard looks a bit excessive for the ship - 5 metres is two full decks and some extra, and I don't think this size of CDS ever had that much freeboard. Lowering your freeboard will increase your hullstrength. The present hullstrength makes this ship a rather flimsy one, and the CDSs of the era were not known for flimsyness.

The clue was the freeboard, I always seas to have too much freeboard on all my designs!

Dalarö, Sweden Coast defence ship laid down 1896

Displacement:
4 380 t light; 4 639 t standard; 4 700 t normal; 4 730 t full load
Loading submergence 412 tons/feet

Dimensions:
311,68 ft x 61,68 ft x 13,12 ft (normal load)
95,00 m x 18,80 m x 4,00 m

Armament:
2 - 10,83" / 275 mm guns (2 Main turrets x 1 guns)
6 - 6,00" / 152 mm guns
10 - 2,24" / 57 mm QF guns
QF guns mounted low & subject to being washed down in a seaway
4 - 0,79" / 20 mm guns
Weight of broadside 1 975 lbs / 896 kg
2 - 18,0" / 457,2 mm submerged torpedo tubes

Armour:
Belt 7,28" / 185 mm, upper belt 1,38" / 35 mm, end belts 1,38" / 35 mm
Belts cover 110 % of normal area
Main turrets 7,28" / 185 mm, 2nd gun shields 1,97" / 50 mm
QF casemates 1,38" / 35 mm
Armour deck 1,18" / 30 mm, Conning tower 7,28" / 185 mm

Machinery:
Coal fired boilers, complex reciprocating steam engines,
Direct drive, 3 shafts, 5 136 ihp / 3 831 Kw = 16,00 kts
Range 1 000nm at 8,00 kts

Complement:
283 - 368

Cost:
£0,480 million / $1,919 million

Distribution of weights at normal displacement:
Armament: 247 tons, 5,3 %
Armour: 1 487 tons, 31,6 %
Belts: 855 tons, 18,2 %, Armament: 273 tons, 5,8 %, Armour Deck: 315 tons, 6,7 %
Conning Tower: 44 tons, 0,9 %, Torpedo bulkhead: 0 tons, 0,0 %
Machinery: 851 tons, 18,1 %
Hull, fittings & equipment: 1 796 tons, 38,2 %
Fuel, ammunition & stores: 319 tons, 6,8 %
Miscellaneous weights: 0 tons, 0,0 %

Metacentric height 3,7

Remarks:
Hull space for machinery, storage & compartmentation is adequate
Room for accommodation & workspaces is adequate
Ship has slow, easy roll, a good, steady gun platform

Estimated overall survivability and seakeeping ability:
Relative margin of stability: 1,27
Shellfire needed to sink: 4 619 lbs / 2 095 Kg = 7,3 x 10,8 " / 275 mm shells
(Approx weight of penetrating shell hits needed to sink ship excluding critical hits)
Torpedoes needed to sink: 1,1
(Approx number of typical torpedo hits needed to sink ship)
Relative steadiness as gun platform: 70 %
(Average = 50 %)
Relative rocking effect from firing to beam: 0,29
Relative quality as seaboat: 1,08

Hull form characteristics:
Block coefficient: 0,652
Sharpness coefficient: 0,47
Hull speed coefficient 'M': 5,69
'Natural speed' for length: 17,65 kts
Power going to wave formation at top speed: 47 %
Trim: 65
(Maximise stabilty/flotation = 0, Maximise steadiness/seakeeping = 100)

Estimated hull characteristics & strength:
Underwater volume absorbed by magazines and engineering spaces: 103,3 %
Relative accommodation and working space: 95,6 %
(Average = 100%)
Displacement factor: 91 %
(Displacement relative to loading factors)
Relative cross-sectional hull strength: 0,97
(Structure weight / hull surface area: 100 lbs / square foot or 490 Kg / square metre)
Relative longitudinal hull strength: 1,34
(for 9,84 ft / 3,00 m average freeboard, freeboard adjustment -3,18 ft)
Relative composite hull strength: 1,00