Shipbucket

Hey folks, after managing to get a lot of very thoughtful and constructive feedback from my last thread I've decided I'll keep posting my personal designs so I can keep getting better, and enjoying discussions of the ships. I design ships for the 1900-1950 period of history in a roleplay I participate in, and help consult people on fleshing out the naval side of any given historical conflict. I get to have a lot of creative freedom when trying to develop warships and the doctrines that demanded them.

First up we have the 5500 ton light cruiser Auduville, a ship on the completely opposite side of the fictitious conflict that the "Righteous Endeavor", subject of the previous post, was on. Auduville served the Karthic Empire, or rather her government in exile. When the Karthic Empire (which despite the name isn't an actual Empire of any kind but rather a minor power) was invaded in 1922, their government fled to their neighbor Torav, and their admiralty went with them. Torav's navy was in complete shambles due to neglect and indifference, and the Karthic Admiralty, veterans of two previous naval wars which they fought through gallantly and with many successes, set about kicking them into fighting shape.



This is Auduville, one of the products of the Karthic naval reconstruction. I drew her after hammering her stats out in Springsharp, and for the sake of brevity I won't clog the post with the whole report. Rather, I'll post up the guts of it, the most important parts:

Displacement: 5,500 tons normal load
Length: 532 feet (159 meters)
Beam: 50 feet (15 meters)
Draft: 15 feet (4.5 meters)
Armament: 8x 6 inch L/45 Quick Firing Guns (4x Twin Mounts), 16x 3 inch Quick Firing Guns (8x Twin Mounts), 8x 12.7mm AA Machine Guns (8x Single Mounts)
Armor: 102mm Belt, 51mm Deck, 102mm Turret Face, 51mm Turret Sides, 51mm Turret Roof, 90mm Barbettes, 102mm Conning Tower
Speed: 31 Knots
Range: 3200 Nautical Miles at 16 knots

The cruiser was designed with operating inside a small sea in mind, smaller than even the Mediterranean theatre, hence her fairly short range. The extremely heavy armor for her size makes her somewhat like a smaller version of the Zara class in essence. She's fairly slow and lacks torpedoes compared to the 5500 ton cruisers Japan built in real life, but she's extremely rugged and well armed against ships of her own side. Given that the Malkorian navy, her opponents, did not posses many battleships (in fact in the same year she was laid down they launched their first and only pair of battleships), it was deemed acceptable that she lack torpedoes. The vast majority of ships in the enemy navy were cruisers of 5500 tons or less and destroyers, against which her eight 6 inch guns would be more than sufficient. The large number of secondary guns reflects the proliferation of torpedo boats in the enclosed waters she was designed for.

All comments are welcome on the drawing, sorry if I was a bit boring with the walls of text! All components of the ship were either drawn by me or used parts sheets.

One of the first things that strikes me is the lack of aerials. Most cruisers of your period were designed as Patrol cruisers to keep the sea lanes safe. If you look at the same types of cruiser for your time period (French Duguay Trouin and the 8" Treaty cruisers) you will see how much was invested in radio/wireless transmitters/receivers, with the very tall masts. That way any contact with an enemy (or supposed enemy Merchant Cruiser) could be broadcast to the world in seconds and replies being received back in minutes.

Having said that, adding the masts/aerials you would need, would add a lot of top weight to an already very narrow design. Balancing any topweight issues would slow the ship down even more to almost WW1 speeds.

Those gun housings look mighty small for twin 6". They look like the Japanese 5.5".

I could try to add a taller mast, but yeah I don't need too much extra top weight. According to ye olde springsharp however, the ship has surspising stability (I guess more weight below the freeboard (dat belt) equals better stability?). I might toy aound with the idea and see what I can make out of it.

The twin 6 inch on the Omaha and Enterprise (British CL) aren't that much bigger, and the twin 15 Cm planned for the Emden is even smaller. The guns aren't true turrets, they're enclosed armored gun houses with shell and powder hoists, just to let you know (given your usageof the term gunhouse I imagine you guessed that). I figured that the size would pass for a relatively simple 6 inch mounting, though i can make it slightly bigger if needed.

My apologies for posting in your thread but I have never quite worked out the 'here' link that people use.



This is my 5,500-6,000 ton patrol cruiser, which is why yours looked familiar to me. Mine does have twin 5.5" gun houses, with single 4" AA. You have left off torpedoes from your cruiser, which most cruisers of the time did have. The speed on mine is only 30 knots which gave me a bit of extra space and weight for other extras. Armour is only 3". The G's are 490x54 feet.

I would be interested in reading your Springsharp if that's ok ?

You can put it in using the spoiler tag from above list of tags buttons, just remove * bits and add your info *add details here*

To answer both your curiosities about the vessels stats, I'll go ahead and post that, thanks for the tip!

Auduville, Karthic Empire Light Cruiser laid down 1926

Displacement:
4,987 t light; 5,227 t standard; 5,550 t normal; 5,808 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(523.35 ft / 518.00 ft) x 50.00 ft x (15.00 / 15.52 ft)
(159.52 m / 157.89 m) x 15.24 m x (4.57 / 4.73 m)

Armament:
8 - 6.00" / 152 mm 45.0 cal guns - 108.92lbs / 49.41kg shells, 200 per gun
Quick firing guns in deck and hoist mounts, 1926 Model
4 x Twin mounts on centreline ends, evenly spread
2 raised mounts - superfiring
16 - 3.00" / 76.2 mm 51.0 cal guns - 14.36lbs / 6.51kg shells, 250 per gun
Quick firing guns in deck mounts, 1926 Model
8 x Twin mounts on sides, evenly spread
8 - 0.50" / 12.7 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 2,000 per gun
Machine guns in deck mounts, 1926 Model
8 x Single mounts on sides amidships
2 raised mounts
Weight of broadside 1,102 lbs / 500 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 4.00" / 102 mm 308.00 ft / 93.88 m 12.00 ft / 3.66 m
Ends: Unarmoured
Main Belt covers 91 % of normal length
Main belt does not fully cover magazines and engineering spaces

- Hull Bulges:
0.00" / 0 mm 0.00 ft / 0.00 m 0.00 ft / 0.00 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 4.00" / 102 mm 2.00" / 51 mm 3.55" / 90 mm
2nd: 1.00" / 25 mm - -

- Armoured deck - single deck: 2.00" / 51 mm For and Aft decks

- Conning towers: Forward 4.00" / 102 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 54,359 shp / 40,552 Kw = 31.00 kts
Range 2,800nm at 16.00 kts
Bunker at max displacement = 581 tons

Complement:
320 - 417

Cost:
£1.775 million / $7.101 million

Distribution of weights at normal displacement:
Armament: 227 tons, 4.1 %
Armour: 1,257 tons, 22.7 %
- Belts: 613 tons, 11.0 %
- Armament: 94 tons, 1.7 %
- Armour Deck: 524 tons, 9.4 %
- Conning Tower: 27 tons, 0.5 %
Machinery: 1,740 tons, 31.4 %
Hull, fittings & equipment: 1,267 tons, 22.8 %
Fuel, ammunition & stores: 563 tons, 10.1 %
Miscellaneous weights: 495 tons, 8.9 %
- Hull below water: 65 tons
- Hull void weights: 90 tons
- Hull above water: 65 tons
- On freeboard deck: 160 tons
- Above deck: 115 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
2,861 lbs / 1,298 Kg = 26.5 x 6.0 " / 152 mm shells or 0.8 torpedoes
Stability (Unstable if below 1.00): 1.16
Metacentric height 2.3 ft / 0.7 m
Roll period: 13.7 seconds
Steadiness - As gun platform (Average = 50 %): 58 %
- Recoil effect (Restricted arc if above 1.00): 0.48
Seaboat quality (Average = 1.00): 0.99

Hull form characteristics:
Hull has a flush deck,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.500 / 0.506
Length to Beam Ratio: 10.36 : 1
'Natural speed' for length: 22.76 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 58
Bow angle (Positive = bow angles forward): 10.00 degrees
Stern overhang: 2.00 ft / 0.61 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 20.00 %, 19.00 ft / 5.79 m, 16.00 ft / 4.88 m
- Forward deck: 30.00 %, 16.00 ft / 4.88 m, 15.00 ft / 4.57 m
- Aft deck: 35.00 %, 15.00 ft / 4.57 m, 15.00 ft / 4.57 m
- Quarter deck: 15.00 %, 15.00 ft / 4.57 m, 14.00 ft / 4.27 m
- Average freeboard: 15.52 ft / 4.73 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 121.1 %
- Above water (accommodation/working, high = better): 156.4 %
Waterplane Area: 17,257 Square feet or 1,603 Square metres
Displacement factor (Displacement / loading): 90 %
Structure weight / hull surface area: 52 lbs/sq ft or 254 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.59
- Longitudinal: 0.66
- Overall: 0.60
Caution: Hull subject to strain in open-sea
Hull space for machinery, storage, compartmentation is cramped
Room for accommodation and workspaces is excellent
Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

Just to note, one piece of advice I got while starting out using SpringSharp is that any ship under 6000 tons should have a cross sectional strength of over .50. The Kuma class report that comes with the program seems to agree and puts her at .63 composite strength. I also decided to cut the range from 3200 to 2800 because she only needs to sail 500 nautical miles or less in any given direction.

I am very, very aware most cruisers had torpedoes in 1928, but I just couldn't find any deck space for them. There is some open space near the aft turrets, but I feared that might subject them to damage from gun blast and render them inoperable. As I said, they're cruiser and destroyer hunters, there are all of two warships in the entire theatre that are too big for her guns to handle and she can outrun them.

My questiosn from the stats would be,

1- why "Main belt does not fully cover magazines and engineering spaces" by how much etc ?

2- I question 4" belts/2" deck on a 1922 CL and a real CL not a 10,000+ treaty 'CL' thing, would just boxs be cheaper/lighter and accept a slightly more 'tinclad' ships in keeping with 1920 CLs ?

3- 2,800nm at 16kts doesn't give you much at 500 from base (especially in wartime when you cant shut off boilers),
that's officially only 1800nm, but you need at least 10% for safety and much worse economy in wartime will be 1/2 or less so 1400nm or less that's only 290t of oil at 31kn you will burn that in 210nm or 6.7 hrs (I would think that's very tight and I'm/Spring-sharp is probably massively underestimating wartime fuel use to keep all boilers lit ready to go ?)

4- what's the date 1926 LD ? your story talks about earlier ?

5 - crew wise I don't think it works 417 - (just guns)(8x20)+(16x20)+(8x3) = 500+? (lots of hand worked guns eat crew once you add hand passing ammo from mags to hoists etc I don't think 20 per gun is unreasonable ?)

I would loke at,
Émile Bertin NM, Sendai-class cruisers IJN, Giussano-class RM ?

1- because I based the main belt length off the drawing and not springsharp. Here's how long the citadel would be if I went with Springsharp's suggested 410 feet:



And here what it looks like if we rate the ships at 30 knots



So, perhaps it would be correct to draw a longer citadel for the ship, perhaps then I might find the needed deck space for the torpedoes.


2- Well Springsharp says I can apply those thicknesses of belt and decks on the ship without overloading the hull. Tinclad cruisers were more conventional for the 1920s, yes, but for a navy that can't afford to replace losses quickly I can't see a floating bomb like those tissue box cruisers working out.

3- The most range I can get out of the ships while keeping the cross sectional strength over .50 is 4600 nautical miles at 16 knots, with the top speed rated at 31 knots. If we downrate the ship to 30 knots, I can raise the cruising speed to 18 knots and keep the same range. Which would put the ship 800 nautical miles ahead of the RL Guissano class in operational range.

4- The naval reforms start in 1922-23 and it takes until 1926 for the first fruits of these labors to be laid down. It seems unrealistic to be that any Admiralty, regardless of excellence, could reform a derelict naval command and implement new vessels in the span of a year or less, it would take at least a few years at minimum (from 23-26 is three years)

5- Crew size does seem small, lemme take my own pass at some basic math. If we assign 20 men per 6 inch gun and 15 per 3 inch gun, we get 400 crew. If we assume 100 men are required to operate the engines at full wartime power we get a crew of 500 men. Add on say, 30 officers for command duties and the crew totals 530, not too much more than Guissano (but she's 1000 tons heavier). Taking off one twin mount per side and keeping the same crew ratios for the guns and engines gives us crew total of 470, or only 30 more than Sendai, which I think works a lot better. It might also free up the deck space needed for some torpedoes. I'll probably do something like that.

I did look at the ships you suggested, and common amongst all of them is a much higher speed rating than Auduville. Guissano is 38 knots, Sendai is 35, and Bertin is 34. The simply subscribe to a completely different design philosophy, one that values speed more than survivability, and it really isn't applicable to the sort of ship I'm trying to create. This ship and her three sisters are the largest cruisers of their navy, and are among the largest cruisers in the entire theatre of operations they are concerned with. They're too valuable to wrap in tinfoil.

Hi Scootia,

I think what SpringSharp is effectively saying is that you've not left enough room for the machinery - it does a calc based off the year to determine volume required per horsepower and figures how to fit that into the hull volume. It's not always entirely correct, so if you've got a comparable real ship that matches the layout and horsepower you can probably disregard it.

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Nice design! Just a few suggestions:

1) Your seakeeping is 0.99, I would definitely get this to 1.00 or better.
2) I would drop the bulges and a lot of the miscellaneous weight, that should help things
3) Definitely try and get the belt problem fixed if possible
4) Get rid of the strained hull if possible

Pity there's no room for torpedoes but you can't have everything...