Considerations about naval designs

Darman wrote:Destroyers sound wonderful, in theory. But what is the range limit on a 1,000t destroyer?

I made a sample DD, running at a top speed of 25 knots, cruising speed of 10 knots. Range is 3500nm.

25-knotter, Charis Destroyer laid down 1900

Displacement:
844 t light; 876 t standard; 1,000 t normal; 1,099 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(305.25 ft / 305.25 ft) x 30.30 ft x (9.25 / 9.86 ft)
(93.04 m / 93.04 m) x 9.24 m x (2.82 / 3.00 m)

Armament:
4 - 4.00" / 102 mm 50.0 cal guns - 33.88lbs / 15.37kg shells, 150 per gun
Breech loading guns in deck mounts, 1900 Model
4 x Single mounts on centreline ends, evenly spread
Weight of broadside 136 lbs / 61 kg

Machinery:
Coal fired boilers, complex reciprocating steam engines,
Direct drive, 2 shafts, 9,399 ihp / 7,012 Kw = 25.00 kts
Range 3,500nm at 10.00 kts
Bunker at max displacement = 224 tons (100% coal)

Complement:
88 - 115

Cost:
£0.122 million / $0.488 million

Distribution of weights at normal displacement:
Armament: 24 tons, 2.4 %
Machinery: 609 tons, 60.9 %
Hull, fittings & equipment: 212 tons, 21.2 %
Fuel, ammunition & stores: 156 tons, 15.6 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
234 lbs / 106 Kg = 7.3 x 4.0 " / 102 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.88
Metacentric height 2.3 ft / 0.7 m
Roll period: 8.4 seconds
Steadiness - As gun platform (Average = 50 %): 73 %
- Recoil effect (Restricted arc if above 1.00): 0.10
Seaboat quality (Average = 1.00): 1.46

Hull form characteristics:
Hull has raised forecastle,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.409 / 0.422
Length to Beam Ratio: 10.07 : 1
'Natural speed' for length: 17.47 kts
Power going to wave formation at top speed: 55 %
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 (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 15.00 ft / 4.57 m, 15.00 ft / 4.57 m
- Forward deck: 30.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Aft deck: 35.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Quarter deck: 15.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Average freeboard: 11.00 ft / 3.35 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 203.5 %
- Above water (accommodation/working, high = better): 123.9 %
Waterplane Area: 5,725 Square feet or 532 Square metres
Displacement factor (Displacement / loading): 33 %
Structure weight / hull surface area: 24 lbs/sq ft or 115 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 0.93
- Overall: 0.54
Hull space for machinery, storage, compartmentation is extremely poor
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

Zakharra wrote: It might be awhile before they build those, and if they do, the shipyard owners and naval developers have the inside track to making them more efficient and fuel effective. Besides, the first all steel ships being designed (the KHVIIs) are 5,000 ton displacement and will be the fastest things at sea until Charis makes the next generation of warship. The KHVIIs will be the baseline of where to start at. All other steel hulled warships will likely have to be able to keep up with that one.

Draken wrote:Could you be so kind to do same simulation with 2,5k ship and with oil as fuel?
I think that light cruise would be better and use the same design only enlarged for heavy and battle cruisers.
I will run few simulation tomorrow for ships within 1-20k tons to check what would be best mix of armor and guns for something similar to Iowa.

Darman wrote:

Zakharra wrote: It might be awhile before they build those, and if they do, the shipyard owners and naval developers have the inside track to making them more efficient and fuel effective. Besides, the first all steel ships being designed (the KHVIIs) are 5,000 ton displacement and will be the fastest things at sea until Charis makes the next generation of warship. The KHVIIs will be the baseline of where to start at. All other steel hulled warships will likely have to be able to keep up with that one.

Until the introduction of torpedoes.... then smaller ships can dart in and engage at close ranges, requiring other smaller ships to screen and fend off torpedo attacks. Additionally, you can only afford to build so many large vessels, if you build cruiser-sized vessels you can build more hulls and thus have them located in more strategically vital places.

PeterZ wrote:Charis actually needs to increase the velocity of the Charisian mark pretty quickly. The best way to do that is for the government to borrow money without under butting the gold mark. The gold production backed promissory note are perfect vehicles for this. Until they are redeemed for gold, they are interest bearing notes. They can be the favored means of storing wealth and allow the gold coins to circulate more quickly.

What better way to introduce those notes than to build a fleet of KHVIIs or larger ships as the mainland upgrades their shore guns? Order the ships and pay with the promissory notes. Those more attractive notes will displace gold as a preferred means of wealth storage. This frees up gold to facilitate the transfer of wealth by circulation more quickly.

Bottom line is that borrowing to build large and complex ships is a great way to infuse money into the system. Money that Charis desperately needs infused into their economy.

Darman wrote:Destroyers sound wonderful, in theory. But what is the range limit on a 1,000t destroyer?

I made a sample DD, running at a top speed of 25 knots, cruising speed of 10 knots. Range is 3500nm.

25-knotter, Charis Destroyer laid down 1900

Displacement:
844 t light; 876 t standard; 1,000 t normal; 1,099 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(305.25 ft / 305.25 ft) x 30.30 ft x (9.25 / 9.86 ft)
(93.04 m / 93.04 m) x 9.24 m x (2.82 / 3.00 m)

Armament:
4 - 4.00" / 102 mm 50.0 cal guns - 33.88lbs / 15.37kg shells, 150 per gun
Breech loading guns in deck mounts, 1900 Model
4 x Single mounts on centreline ends, evenly spread
Weight of broadside 136 lbs / 61 kg

Machinery:
Coal fired boilers, complex reciprocating steam engines,
Direct drive, 2 shafts, 9,399 ihp / 7,012 Kw = 25.00 kts
Range 3,500nm at 10.00 kts
Bunker at max displacement = 224 tons (100% coal)

Complement:
88 - 115

Cost:
£0.122 million / $0.488 million

Distribution of weights at normal displacement:
Armament: 24 tons, 2.4 %
Machinery: 609 tons, 60.9 %
Hull, fittings & equipment: 212 tons, 21.2 %
Fuel, ammunition & stores: 156 tons, 15.6 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
234 lbs / 106 Kg = 7.3 x 4.0 " / 102 mm shells or 0.2 torpedoes
Stability (Unstable if below 1.00): 1.88
Metacentric height 2.3 ft / 0.7 m
Roll period: 8.4 seconds
Steadiness - As gun platform (Average = 50 %): 73 %
- Recoil effect (Restricted arc if above 1.00): 0.10
Seaboat quality (Average = 1.00): 1.46

Hull form characteristics:
Hull has raised forecastle,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.409 / 0.422
Length to Beam Ratio: 10.07 : 1
'Natural speed' for length: 17.47 kts
Power going to wave formation at top speed: 55 %
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 (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 15.00 ft / 4.57 m, 15.00 ft / 4.57 m
- Forward deck: 30.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Aft deck: 35.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Quarter deck: 15.00 %, 10.00 ft / 3.05 m, 10.00 ft / 3.05 m
- Average freeboard: 11.00 ft / 3.35 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 203.5 %
- Above water (accommodation/working, high = better): 123.9 %
Waterplane Area: 5,725 Square feet or 532 Square metres
Displacement factor (Displacement / loading): 33 %
Structure weight / hull surface area: 24 lbs/sq ft or 115 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.50
- Longitudinal: 0.93
- Overall: 0.54
Hull space for machinery, storage, compartmentation is extremely poor
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

Jeroswen wrote:What you have listed pretty close the the Smith Class destroyer from the US Navy.

fallsfromtrees wrote:It's all very well to use existing ship classes for the design of Charis destroyers, but so far as I have been able to find, none of the references give a range, and the 3500nm range for the hypothetical 1000 tonner had no justification for it. Do we have ranges for the Smith class or the Cassin class destroyers? I did note that the Cassin destroyers built the Bath Iron Works used triple expansion steam engines, and that they could take one screw out of service to improve cruising range, but no ranges were given in the articles I perused.

doug941 wrote:

fallsfromtrees wrote:It's all very well to use existing ship classes for the design of Charis destroyers, but so far as I have been able to find, none of the references give a range, and the 3500nm range for the hypothetical 1000 tonner had no justification for it. Do we have ranges for the Smith class or the Cassin class destroyers? I did note that the Cassin destroyers built the Bath Iron Works used triple expansion steam engines, and that they could take one screw out of service to improve cruising range, but no ranges were given in the articles I perused.

The range of a warship would be dependent on several factors. Oil is more energy dense and does not require stokers. The engines themselves become important as well. From 0 to +/- 20 knots, triple expansion engines are more economical, from +/- 20 and up turbines are the way to go.