Can the new river class ironclads bypass the Salthar Canal?

runsforcelery wrote:Okay, so I’ve been playing with the cruiser design for the last couple of days, and Sharon and I are flying to Des Moines this morning (leaving Greenville at six a.m.), so since I was getting up and packing early, I spent the last couple of hours playing with the River-class ironclads gunboats. It was interesting to see how close they came, in a lot of ways, in my original design to what the software produced. In fact, the actual tonnages and displacements are very, very close, but I had significantly overestimated the coal consumption, assuming that the software gets it right. It worked out pretty well, anyway, because I’d obviously underestimated weights somewhere else. They came out a little slower than my maximum speed estimate (I could’ve gotten them up to my original numbers, but while they probably would have survived standard brown water conditions in that configuration, they probably wouldn’t have survived the voyage from Charis to Siddarmark, so I went with the lower-speed) but with a lot more endurance.

Anyway, here they are:

River-class ironclad gunboat
Imperial Charisian Navy
River barge conversion
Delthak Dockyard, 895


Displacement:
Light: 1,058 tons
Standard: 1,323 tons
Normal: 1,386 tons
Full load: 1,436 tons

Dimensions:
Length (overall / waterline): 140’
Beam: 40’
Draft (normal): 10’
Draft (deep) 10/4”

Armament:
24 x 30-pdr ML smoothbores, 3 x 11 x 3 (solid shot = 32 pounds; HE shell = 18 pounds; 250 rounds/gun)
Weight of broadside (shot): 352 pounds
Weight of broadside (shell): 198 pounds
Ahead/Astern (shot): 96 pounds
Ahead/Astern (shell): 54 pounds

Armor:
Casemate: thickness = 3”; length= 126’; height = 12’; inclined 16˚
Hull (fwd/aft of casemate): thickness = 3”; length = 14’; height = 6’; no slope
Casemate roof & decks: 1”
Conning Tower: 6”; no slope

Machinery:
Coal fired boilers, double-expansion engines, direct drive, 2 shafts, 65.21 sdp (1,663 shp) = 15 knots (13 Old Earth knots)
Range: 1,800 nm @ 9.5 knots (8.25 Old Earth knots)
3,500 nm @ 7 knots (6 Old Earth knots)
Bunker: (normal): 62 tons
Bunker (maximum): 112 tons

Complement: 197

Cost: CM 126,000

Distribution of weights at normal displacement:
Armament: 140 tons, 10.1 %
Armour: 334 tons, 24.1 %
Machinery: 241 tons, 17.4 %
Hull, fittings & equipment: 343 tons, 24.7 %
Fuel, ammunition & stores: 328 tons, 23.7 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (penetrating hits to sink ship): 17 x 30-pounder shells
Stability (Unstable if below 1.00): 1.66
Metacentric height 2.9 ft / 0.9 m
Roll period: 9.8 seconds
Seaboat quality (Average = 1.00): 0.85

Hull form characteristics:
Hull has low forecastle, low quarterdeck , a vertical bow and a round stern
Block coefficient (normal/deep): 0.866 / 0.868
Length to Beam Ratio: 3.50 : 1
'Natural speed' for length: 11.83 kts
Power going to wave formation at top speed: 66 %
Freeboard:
Foredeck: 4’ (length = 7’)
Casemate: 10’ (length = 126’)
Average: 8.8’
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 104.8 %
- Above water (accommodation/working, high = better): 88.3 %
Waterplane Area: 5,238 Square feet or 487 Square metres
Displacement factor (Displacement / loading): 108 %
Structure weight / hull surface area: 64 lbs/sq ft or 310 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.78
- Longitudinal: 4.63
- Overall: 0.93
Caution: Hull subject to strain in open-sea
Adequate machinery, storage, compartmentation space
Cramped accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather.

**********************************************

River-class ironclad gunboat (refit)
Imperial Charisian Navy
River barge conversion
Delthak Dockyard, 895

Displacement:
Light: 1,172 tons
Standard: 1,430 tons
Normal: 1,493 tons
Full load: 1,543 tons

Dimensions:
Length (overall / waterline): 140’
Beam: 40’
Draft (normal): 10’0.5”
Draft (deep) 10’4.5”

Armament:
20* x 6”/45 M895 BL guns (3 x 9 x 3) (AP shell = 115 pounds; 250 rounds/gun)
Weight of broadside: 1,035 pounds
Ahead/Astern: 345 pounds
Broadsides reduced by 2 guns each beause of weight differential between weapons.

Armor:
Casemate: thickness = 3”; length= 126’; height = 12’; inclined 16˚
Hull (fwd/aft of casemate): thickness = 3”; length = 14’; height = 6’; no slope
Casemate roof & decks: 1”
Conning Tower: 6”; no slope

Machinery:
Coal fired boilers, double-expansion engines, direct drive, 2 shafts, 65.21 sdp (1,663 shp) = 15 knots (13 Old Earth knots)
Range: 1,800 nm @ 9.5 knots (8.25 Old Earth knots)
3,500 nm @ 7 knots (6 Old Earth knots)
Bunker: (normal): 62 tons
Bunker (maximum): 112 tons

Complement: 157

Cost: CM 162,000


Distribution of weights at normal displacement:
Armament: 247 tons, 17.8 %
Armour: 334 tons, 24.1 %
Machinery: 241 tons, 17.4 %
Hull, fittings & equipment: 343 tons, 24.7 %
Fuel, ammunition & stores: 328 tons, 23.7 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (penetrating hits to sink ship): 10 x 6” AP
Stability (Unstable if below 1.00): 1.66
Metacentric height 2.9 ft / 0.9 m
Roll period: 9.8 seconds
Seaboat quality (Average = 1.00): 0.85

Hull form characteristics:
Hull has low forecastle, low quarterdeck , a vertical bow and a round stern
Block coefficient (normal/deep): 0.866 / 0.868
Length to Beam Ratio: 3.50 : 1
'Natural speed' for length: 11.83 kts
Power going to wave formation at top speed: 66 %
Freeboard:
Foredeck: 4’ (length = 7’)
Casemate: 10’ (length = 126’)
Average: 8.8’
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 104.8 %
- Above water (accommodation/working, high = better): 88.3 %
Waterplane Area: 5,238 Square feet or 487 Square metres
Displacement factor (Displacement / loading): 108 %
Structure weight / hull surface area: 64 lbs/sq ft or 310 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.78
- Longitudinal: 4.63
- Overall: 0.93
Caution: Hull subject to strain in open-sea
Adequate machinery, storage, compartmentation space
Cramped accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

*************************************************

Delthak II – class broadside ironclad gunboat
Imperial Charisian Navy
Tellesberg, King’s Harbor, & Delthak DYs
All laid down 895 YoG
All launched & Commissioned: 896 YoG

Displacement:
Light: 1,181 tons
Standard: 1,465 tons
Normal: 1,529 tons
Full Load: 1,580 tons

Dimensions:
Length (waterline): 160’
Length (overall): 160’
Beam: 40’
Draft (normal): 10’
Draft (full): 10’3”

Armament:
22 x 6”/45 M895 BL guns 3 x 11 x 3 (115-pound AP shell; 200/gun)
Weight of broadside (13 guns): 1,495 pounds
Weight fore or aft (3 guns): 345 pounds

Armor:
Casemate: thickness= 3”; length = 146’; height = 14’; inclined 16˚
Freeboard fore & aft: thickness=3”; length = 14’; height = 4’
Casemate roof/decks: 1”
Conning tower: 6” (no slope)

Machinery:
Coal fired boilers, double-expansion engines, direct drive, 2 shafts, 45 sdp (1,147 shp) = 14 knots (12.2 Old Earth knots)
Range 1,800nm at 9.5 knots (8.25 Old Earth knots)
Range 3,500 nm at 5.7 knots (5 Old Earth knots)
Bunker (normal): 59 tons
Bunker (max displacement): 115 tons

Complement: 158

Cost: CM 168,000

Distribution of weights at normal displacement:
Guns: 281 tons, 18.4 %
Armor: 286 tons, 18.7 %
Machinery: 166 tons, 10.9 %
Hull, fittings & equipment: 448 tons, 29.3 %
Fuel, ammunition & stores: 348 tons, 22.7 %

Overall survivability and seakeeping ability:
Survivability (penetrating hits to sink ship): 17 x 6”/45
Stability (Unstable if below 1.00): 1.81
Metacentric height 3.3 ft / 1.0 m
Roll period: 9.2 seconds
Steadiness as gun platform (Average = 50 %): 68 %
Seaboat quality (Average = 1.00): 1.35

Hull form characteristics:
Hull has low forecastle, low quarterdeck , a normal bow and a round stern
Block coefficient (normal/deep): 0.836 / 0.838
Length to Beam Ratio: 4.00 : 1
'Natural speed' for length: 14.6 knots (12.65 Old Earth knots)s
Power going to wave formation at top speed: 57 %
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):
- Forecastle: 10.00 %, 4.00 ft
- Forward deck: 30.00 %, 10.00 ft
- Aft deck: 50.00 %, 10.00 ft
- Quarter deck: 10.00 %, 4.00 ft
- Average: 8.80 ft
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 105.1 %
- Above water (accommodation/working, high = better): 91.7 %
Waterplane Area: 5,823 Square feet
Displacement factor (Displacement / loading): 100 %
Structure weight / hull surface area: 82 lbs/sq ft
Hull strength (Relative):
- Cross-sectional: 1.02
- Longitudinal: 4.66
- Overall: 1.19
Adequate machinery, storage, compartmentation space
Adequate accommodation and workspace room
Good seaboat, rides out heavy weather easily

********************************************

I think the biggest surprise I got was when the Delthak IIs, the purpose-built ironclads, ended up rated as a “good seaboat, rides out heavy weather easily.” I expected to improve their seakeeping ability when I made them 20 feet longer (which will make them less useful than the Rivers on the older canals) and settled for lower-power engines (if you remember, folks were reflecting that the Rivers were over-powered), but I didn’t expect as much improvement as I got. Mind you, I doubt anyone is going to enjoy getting through a storm at sea in one of these, but they probably won’t panic at the mere thought of facing one.

I’m also fiddling around with a Shan-wei-class superdreadnought mounting 10 x 16”/45 firing the USN’s superheavy shell. It’s looking like coming out around 70-75,000 tons standard displacement with oil-fired boilers and geared turbines. Of course, that’s providing Montana-style underwater protection on the theory that while it probably won’t have to deal with torpedoes, it might have to deal with a fairly serious mine threat by the time they were laid down . . . assuming, of course, that any such monstrosity might ever be built . . . .

Strolls away whistling.

captinjoehenry wrote:Here is the design for the River I and the Delthak II which I think is the River II

runsforcelery wrote:I’m also fiddling around with a Shan-wei-class superdreadnought . . . .

JeffEngel wrote:

runsforcelery wrote:I’m also fiddling around with a Shan-wei-class superdreadnought . . . .

What on Safehold would possess them to name a ship class that?!

Weird Harold wrote:

JeffEngel wrote:What on Safehold would possess them to name a ship class that?!

After the "Big Reveal" it might be a way of honoring her sacrifice. Charis certainly doesn't need a "Superreadnought" for the current war.

runsforcelery wrote:

phillies wrote:Given that we already have FTL travel, adjusting laws of nature to give better battleships is fairly easy.

"Notwithstanding speculation, Bernoulli erred; changing the speed of a gas around an airfoil has no effect on the pressure the gas exerts on either side of the foil. For this reason, nature will never produce any flying creatures larger than insects; correspondingly, only dirigibles and antigravity launches offer the possibility of flight.

Water resembles many polymer solutions in that it is highly shear thinning. If you stir it rapidly, its viscosity falls to zero. For this reason, the submarine of Pirate Captain Piraticus cannot be made to work. On the command "emergency speed", the superhighspeed submarine propellers of the captain would churn the water, eliminating water's viscosity, and his submarine would glide to a stop. For this reason, torpedo weapons are far slower than warships.

There, that lets us build important vessels like the

RCN Smiting Fist of God

1500 feet long
200 foot beam

Main armament 6 three-gun turrets holding 21" guns
Secondary armament 24 x 10" in staggered deck twin turrets
Tertiary armament...

propulsion three sets of 40' sidewheels mounted behind the main armor belt -- for high thrust at low RPMs, paddle wheels win, though they are a bit inefficient, as witness the hypothetical iceberg-towing tugs of the 1970s and 1980s.

Weight? Oh, I don't know, do we think we can fit this in 200,000 tons?

You should NOT have gone there . . . .

BTW, this ship alone equals 81% of the total capital ship tonnage allocated to the USN under the terms of the Washington Treay.

*************************************
HMS Unstoppable,

Displacement:
411,591 t light; 427,374 t standard; 437,747 t normal; 446,045 t full load

Dimensions:
Length (waterline): 1,500’
Length (overall) 1,533’6”
Beam: 225’
Draft (normal): 52’
Draft (deep): 52’9"

Armament:
20 - 18"/47, 5x4, 3,800-lb AP shell; 200.gun
24 – 10”/45, 6x2, 625-lb AP shell, 250/gun
18 – 6”/60; 6x3, 150-lb AP shell; 300/ gun
Weight of broadside (20 x 18", 12 x 10", 12 x 6") = 85,300 lbs (42.65 tons)
Torpedoes:
16 - 24", 2.519 t each, in 4 sets of deck mounted quadruple side rotating tubes
32 reload torpedoes stowed below deck

Armour:
Main: thickness = 20.0"; length = 750’; height = 24’
Ends: thicknmess = 5”; length = 750’; height = 18/7”
Upper: thickness = 12.5”; length = 750’; height = 8’
Main belt inclined 12°
Torpedo Bulkhead : 4”
Quadruple 18” turrets: face = 22”; sides = 10”; roof = 18”
Double 10” turrets: face= 12”; sides = 8”; roof = 10”
Triple 6” turrets: face = 7”; sides = 4.5”; roof = 4.5”
Deck (cumulative thickness of multiple decks):
Forecastle & quarterdeck: 6.5”
Machinery & magazines: 12.25”
Conning towers: Forward 19"

Machinery:
Oil fired boilers, steam turbines, turbo-electric drive, 10 shafts, 605,092 shp = 30.00 kts
Range 12,000nm at 12.00 kts
Bunker at normal displacement = 10,373 tons
Bunker at max displacement = 18,671 tons

Complement: 10,420

Cost: CM 55,000,000 (896 marks)

Distribution of weights at normal displacement:
Armament: 15,885 tons, 3.6 %
- Guns: 15,804 tons, 3.6 %
- Weapons: 81 tons, 0.0 %
Armor: 106,058 tons, 24.2 %
- Belts: 23,167 tons, 5.3 %
- Torpedo bulkhead: 5,031 tons, 1.1 %
- Armament: 19,453 tons, 4.4 %
- Armor Deck: 56,048 tons, 12.8 %
- Conning Tower: 2,360 tons, 0.5 %
Machinery: 14,476 tons, 3.3 %
Hull, fittings & equipment: 275,138 tons, 62.9 %
Fuel, ammunition & stores: 26,156 tons, 6.0 %
Miscellaneous weights: 34 tons, 0.0 %
- Hull below water: 34 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
1,268,618 lbs = 435.1 x 18.0 " AP shells or 316.6 torpedoes
Stability (Unstable if below 1.00): 1.02
Metacentric height 17.6 ft
Roll period: 22.5 seconds
Steadiness - As gun platform (Average = 50 %): 100 %
- Recoil effect (Restricted arc if above 1.00): 0.27
Seaboat quality (Average = 1.00): 1.07

Hull form characteristics:
Hull has a flush deck, an extended bulbous bow and a round stern w/long forecastle
Block coefficient (normal/deep): 0.873 / 0.874
Length to Beam Ratio: 6.67 : 1
'Natural speed' for length: 38.73 kts
Power going to wave formation at top speed: 42 %
Trim (Max stability = 0, Max steadiness = 100): 96
Bow angle (Positive = bow angles forward): 40.00 degrees
Stern overhang: 0.00 ft / 0.00 m
Freeboard (% = length of deck as a percentage of waterline length):
-Forecastle: 40’-32’
- Forward deck: 32’-28’
- Aft deck: 28’
-Quarterdeck: 28’
-Average: 30’8.2”
Ship tends to be wet forward

Ship space, strength and comments:
Hull space below water (magazines/engines, low = better): 31.2 %
Hull Space above water (accommodation/working, high = better): 202.7 %
Waterplane Area: 317,667 Square feet
Displacement factor (Displacement / loading): 215 %
Structure weight / hull surface area: 756 lbs/sq ft
Hull strength (Relative): cross-sectional = 2.65; longitudinal = 1.55; Overall= 1.78
Excellent machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform

****************************************
The software’s parameters cut off at 1950, so I don’t know if it would be possible to reduce the number of propeller shafts or not. I suspect they could probably be reduced some, but it’s also possible one might want to go with a podded approach using turbo electric machinery, which is the drive system I used to compute engine weights. Of course, that would be just a tiny problem for Safehold unless the bombardment platform’s already been taken out of play, at which point one must wonder why anyone would build one of these. Except, of course, that the answer is simplicity itself. As myself, Merlin has always been fascinated by the possibilities and what-ifs of battleship design. So, having disposed of the bombardment platform, he has continued to use his recon skimmer to destroy any powered aircraft, thus creating the perfect laboratory in which to see what might have been acompished in that arena. And, with the introduction of nuclear power . . . . .

Oh, I so don’t need to go there!

captinjoehenry wrote:Here is the design for the River I and the Delthak II which I think is the River II
Real Big Snip

SYED wrote:How big a force would the church have placed on the canal? With steam engine speed they might be able to get to all of them. To best knowledge, silkily doesn't have a proper military and despair had its army shattered. So some properly armed soldiers could hold the key point against any available force. Even temporily claiming the canal, gives silkier separation from the others. So they might not be eager to aid the church in retaking them.