WesWorld

Capitan Orella 1896

Disp 300 tonnes
Length 213 ft
Beam 21.5 ft
Draught (trial) 5.875 ft

Cb = 0.3903

Ian

www.springsharp.com

Quoted

Originally posted by IanRG
I would suggest that going less than 0.4 Cb is fraught with danger and if you allow it, it should limited to small high speed planing or semi-planing hulls.

So I ask the Board if we should stick to this and probably add it to the Gentlemen´s rules? If the majority asks for a lower bc as minimum I´d also accept 0,38 but anything less doesn´t seem to make much sense from what Ian told us.

Your input please.

HoOmAn

A limit of 0.38 is fine with me, but I'm using 10:1 length:beam ratios and 0.40 Cb for my destroyers anyway.

A "practical limit" of BC 0.38 is fine with me.

A limit of 0.40 would be fine by me, most of my older designs have a .42 to.45 setting (useing springstyle).

Quoted

Capitan Orella 1896

Disp 300 tonnes
Length 213 ft
Beam 21.5 ft
Draught (trial) 5.875 ft

Cb = 0.3903

One wonders....

Thank you.

Interestingly the 1914 Jane's has simmilar specifications, the the assumtions is the newer the book, the more accurate the information of a vessel.

I'll need to redesign the new destroyer, but I'll like to keep it light, with a fair range, and a few destroyer guns to keep her compeditive. (3 x 110mm was the suggestion from Wes).

Either that or I scrape the idea of light destroyers and build all leader size ships with a caliber between 4.33 and 5.9 inches. 4.33 is a nice size, right between the 4 inch and 4.7 inch guns, but it will probably be lacking in firepower into the 30s and 40s.

Guardia Marina Contrerra

Chilean Destroyer laid down 1927

Displacement:
855 t light; 897 t standard; 965 t normal; 1,015 t full load

Dimensions: Length overall / water x beam x draught
300.00 ft / 289.00 ft x 29.00 ft x 10.00 ft (normal load)
91.44 m / 88.09 m x 8.84 m x 3.05 m

Armament:
3 - 4.33" / 110 mm guns in single mounts, 40.59lbs / 18.41kg shells, 1927 Model
Quick firing guns in deck mounts
on centreline ends, majority forward, 1 raised mount
4 - 2.29" / 58.2 mm guns in single mounts, 6.00lbs / 2.72kg shells, 1927 Model
Quick firing guns in deck mounts
on side, evenly spread
2 - 1.46" / 37.0 mm guns (1x2 guns), 1.55lbs / 0.70kg shells, 1927 Model
Anti-aircraft guns in deck mount
on centreline
6 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1927 Model
Machine guns in deck mounts
on side, evenly spread, 2 raised mounts
Weight of broadside 149 lbs / 68 kg
Shells per gun, main battery: 250
2 - 21.0" / 533.4 mm above water torpedoes

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 2 shafts, 27,500 shp / 20,515 Kw = 32.27 kts
Range 5,000nm at 10.00 kts (Bunkerage = 122 tons)

Complement:
86 - 112

Cost:
£0.423 million / $1.691 million

Distribution of weights at normal displacement:
Armament: 19 tons, 1.9 %
Machinery: 505 tons, 52.3 %
Hull, fittings & equipment: 327 tons, 33.9 %
Fuel, ammunition & stores: 110 tons, 11.4 %
Miscellaneous weights: 5 tons, 0.5 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
279 lbs / 127 Kg = 6.9 x 4.3 " / 110 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.26
Metacentric height 1.2 ft / 0.4 m
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.25
Seaboat quality (Average = 1.00): 1.06

Hull form characteristics:
Hull has rise forward of midbreak, low quarterdeck
Block coefficient: 0.403
Length to Beam Ratio: 9.97 : 1
'Natural speed' for length: 17.00 kts
Power going to wave formation at top speed: 70 %
Trim (Max stability = 0, Max steadiness = 100): 66
Bow angle (Positive = bow angles forward): 24.63 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 24.00 ft / 7.32 m
- Forecastle (20 %): 18.00 ft / 5.49 m
- Mid (50 %): 17.00 ft / 5.18 m (10.00 ft / 3.05 m aft of break)
- Quarterdeck (15 %): 7.00 ft / 2.13 m (10.00 ft / 3.05 m before break)
- Stern: 7.00 ft / 2.13 m
- Average freeboard: 13.88 ft / 4.23 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 185.2 %
- Above water (accommodation/working, high = better): 121.8 %
Waterplane Area: 4,889 Square feet or 454 Square metres
Displacement factor (Displacement / loading): 51 %
Structure weight / hull surface area: 30 lbs/sq ft or 145 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 3.08
- Overall: 0.60
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform

So does anybody oppose those 0,38 min for block coef.? Otherwise I´ll add it to our G-Rules.

I guess 0.38 is acceptable for small, fast combatants. I would not expect to see it on anything larger than a torpedo boat, however...

Agreed. For any new ships.

Okay, edited the G-Rules...

Now with 3 inch guns in place of 6 pounders.

Guardia Marina Contrerra

Chilean Destroyer laid down 1927

Displacement:
850 t light; 897 t standard; 965 t normal; 1,015 t full load

Dimensions: Length overall / water x beam x draught
300.00 ft / 289.00 ft x 29.00 ft x 10.00 ft (normal load)
91.44 m / 88.09 m x 8.84 m x 3.05 m

Armament:
3 - 4.33" / 110 mm guns in single mounts, 40.59lbs / 18.41kg shells, 1927 Model
Quick firing guns in deck mounts
on centreline ends, majority forward, 1 raised mount
4 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1927 Model
Dual purpose guns in deck mounts
on side, evenly spread
2 - 1.46" / 37.0 mm guns (1x2 guns), 1.55lbs / 0.70kg shells, 1927 Model
Anti-aircraft guns in deck mount
on centreline
6 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1927 Model
Machine guns in deck mounts
on side, evenly spread, 2 raised mounts
Weight of broadside 179 lbs / 81 kg
Shells per gun, main battery: 250
2 - 21.0" / 533.4 mm above water torpedoes

Machinery:
Oil fired boilers, steam turbines,
Direct drive, 2 shafts, 27,500 shp / 20,515 Kw = 32.27 kts
Range 5,000nm at 10.00 kts (Bunkerage = 122 tons)

Complement:
86 - 112

Cost:
£0.431 million / $1.723 million

Distribution of weights at normal displacement:
Armament: 22 tons, 2.3 %
Machinery: 499 tons, 51.7 %
Hull, fittings & equipment: 329 tons, 34.0 %
Fuel, ammunition & stores: 115 tons, 11.9 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
276 lbs / 125 Kg = 6.8 x 4.3 " / 110 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.27
Metacentric height 1.2 ft / 0.4 m
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.30
Seaboat quality (Average = 1.00): 1.06

Hull form characteristics:
Hull has rise forward of midbreak, low quarterdeck
Block coefficient: 0.403
Length to Beam Ratio: 9.97 : 1
'Natural speed' for length: 17.00 kts
Power going to wave formation at top speed: 70 %
Trim (Max stability = 0, Max steadiness = 100): 66
Bow angle (Positive = bow angles forward): 24.63 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 24.00 ft / 7.32 m
- Forecastle (20 %): 18.00 ft / 5.49 m
- Mid (50 %): 17.00 ft / 5.18 m (10.00 ft / 3.05 m aft of break)
- Quarterdeck (15 %): 7.00 ft / 2.13 m (10.00 ft / 3.05 m before break)
- Stern: 7.00 ft / 2.13 m
- Average freeboard: 13.88 ft / 4.23 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 186.1 %
- Above water (accommodation/working, high = better): 121.8 %
Waterplane Area: 4,889 Square feet or 454 Square metres
Displacement factor (Displacement / loading): 50 %
Structure weight / hull surface area: 30 lbs/sq ft or 145 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 3.09
- Overall: 0.60
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform