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Heavy, post treaty cruiser, ca 1938
http://67.205.157.234/forums/viewtopic.php?f=14&t=5761
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Author:  Psilander [ December 18th, 2014, 11:10 pm ]
Post subject:  Heavy, post treaty cruiser, ca 1938

In my refurbishment of my cruisers in my AU the time has come for the Uppland-class heavy cruisers. They ar a response to German and Japanese Heavy cruisers like Hipper andMogami.

This is her original SS data. I not entierly happy with the AAA layout, is there to many calibers?
What do you Think?
Quote:
Uppland, Sweden Cruiser laid down 1938

Displacement:
9 240 t light; 9 698 t standard; 10 100 t normal; 10 422 t full load

Dimensions: Length overall / water x beam x draught
619,92 ft / 590,55 ft x 59,06 ft x 21,33 ft (normal load)
188,95 m / 180,00 m x 18,00 m x 6,50 m

Armament:
9 - 8,00" / 203 mm guns (3x3 guns), 256,00lbs / 116,12kg shells, 1938 Model
Breech loading guns in turrets (on barbettes)
on centreline ends, majority aft, 1 raised mount aft - superfiring
12 - 4,13" / 105 mm guns (4 mounts), 35,32lbs / 16,02kg shells, 1934 Model
Dual purpose guns in turrets (on barbettes)
on side, all amidships, 4 raised guns - superfiring
8 - 2,95" / 75,0 mm guns (4x2 guns), 12,87lbs / 5,84kg shells, 1934 Model
Anti-aircraft guns in deck mounts with hoists
on side, evenly spread, all raised mounts
32 - 1,57" / 40,0 mm guns (16x2 guns), 1,95lbs / 0,88kg shells, 1936 Model
Anti-aircraft guns in deck mounts
on side, evenly spread, all raised mounts
Weight of broadside 2 893 lbs / 1 312 kg
Shells per gun, main battery: 150
12 - 21,0" / 533,4 mm above water torpedoes

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 7,28" / 185 mm 360,89 ft / 110,00 m 9,22 ft / 2,81 m
Ends: 0,98" / 25 mm 180,45 ft / 55,00 m 9,22 ft / 2,81 m
49,21 ft / 15,00 m Unarmoured ends
Upper: 0,79" / 20 mm 400,26 ft / 122,00 m 8,01 ft / 2,44 m
Main Belt covers 94 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 5,91" / 150 mm 1,97" / 50 mm 5,91" / 150 mm
2nd: 0,98" / 25 mm 0,39" / 10 mm 0,98" / 25 mm

- Armour deck: 1,57" / 40 mm, Conning tower: 2,95" / 75 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 3 shafts, 73 946 shp / 55 164 Kw = 31,00 kts
Range 5 000nm at 12,00 kts (Bunkerage = 724 tons)

Complement:
503 - 654

Cost:
£5,133 million / $20,531 million

Distribution of weights at normal displacement:
Armament: 362 tons, 3,6 %
Armour: 2 390 tons, 23,7 %
- Belts: 1 182 tons, 11,7 %
- Torpedo bulkhead: 0 tons, 0,0 %
- Armament: 516 tons, 5,1 %
- Armour Deck: 662 tons, 6,6 %
- Conning Tower: 30 tons, 0,3 %
Machinery: 2 025 tons, 20,0 %
Hull, fittings & equipment: 4 413 tons, 43,7 %
Fuel, ammunition & stores: 860 tons, 8,5 %
Miscellaneous weights: 50 tons, 0,5 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
12 613 lbs / 5 721 Kg = 49,3 x 8,0 " / 203 mm shells or 1,6 torpedoes
Stability (Unstable if below 1.00): 1,07
Metacentric height 2,6 ft / 0,8 m
Roll period: 15,5 seconds
Steadiness - As gun platform (Average = 50 %): 53 %
- Recoil effect (Restricted arc if above 1.00): 0,85
Seaboat quality (Average = 1.00): 1,07

Hull form characteristics:
Hull has raised forecastle
Block coefficient: 0,475
Length to Beam Ratio: 10,00 : 1
'Natural speed' for length: 24,30 kts
Power going to wave formation at top speed: 54 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 35,00 degrees
Stern overhang: 9,84 ft / 3,00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 27,89 ft / 8,50 m
- Forecastle (20 %): 22,97 ft / 7,00 m (21,33 ft / 6,50 m aft of break)
- Mid (50 %): 21,33 ft / 6,50 m
- Quarterdeck (30 %): 13,12 ft / 4,00 m
- Stern: 13,12 ft / 4,00 m
- Average freeboard: 18,77 ft / 5,72 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 93,7 %
- Above water (accommodation/working, high = better): 129,3 %
Waterplane Area: 22 729 Square feet or 2 112 Square metres
Displacement factor (Displacement / loading): 108 %
Structure weight / hull surface area: 119 lbs/sq ft or 582 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,96
- Longitudinal: 1,41
- Overall: 1,00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
For her looks I imagine a mix of RN Crown Colony/ IJN Mogami/ IRL RSwN Göta lejon(with new bridge). The two last ships (Småland and Halland) will be completed as CGL Äran in the 1950s/ 60s. (old SB attempt for HSwMS Äran)

Author:  Blackbuck [ December 18th, 2014, 11:14 pm ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

Maybe go for a homogeneous 90mm battery if you're worried about calibre overlap?

Author:  Psilander [ December 18th, 2014, 11:19 pm ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

Blackbuck wrote:
Maybe go for a homogeneous 90mm battery if you're worried about calibre overlap?
or just skip the 75mm guns, and go for 21cm - 105mm - 40mm, I have no 90mm in my inventory, just some very old 88mm from pre ww1

Author:  Blackbuck [ December 18th, 2014, 11:31 pm ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

That seems a fair enough route to take.

Author:  JSB [ December 19th, 2014, 4:02 am ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

I would just have the 105mm guns (and how many do you have 12 in 4 mounts, so triples but then you have 4 raise guns ? looking at web site gives 6 mounts ?)
What ever you do I think you have plenty of AA for 38.

A few qs about the ship,
What’s its role ? (I guess from Sweden its close Baltic fighting ?)
- Is 31 kn sufficient ? (other Swedish CA is 33 kn)
- Do you need float planes on board ? (or can they be land based close by)
- Do you need the torpedoes ? (if you are going to be leading flotillas of TB/DDs)
- How do you balance post treaty (+10,000t or much more 13000t) with Swedish budgets (-10,000t or much less 7000t)
- Your protection is very belt heavy ? (185mm is very thick !)

JSB

Author:  eltf177 [ December 19th, 2014, 10:41 am ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

Agreed, the 75mm cannons are overkill and taking valuable deck space. Remove and add more light AA or save the weight for the inevitable upgrades...

Author:  apdsmith [ December 19th, 2014, 11:10 am ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

Hi Psilander,

I'd echo what the others here have said - in USN service, for instance, the 3"/76.2mm replaced the 40mm Bofors rather than augmenting it.

Regards,
Adam

Author:  Krakatoa [ December 19th, 2014, 11:12 am ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

looks ok, but...
the length to breadth ratio for triple 8" is a bit narrow. The Mogamis had to have bulges fitted almost immediately to meet stability problems. I can see your ship having similar problems. There is a lot of armour for the displacement. A lot of minor weaponry is also going to put pressure on the stability. It is one of the reasons I do not like Springsharp, it can say everything is wonderful, but reality shows it to be out of synch. The US was the only country with triple 8" and the breadth on all those ships was 62ft or more.

You have a ship to meet Mogami / Hipper where the Mogamis were a very flawed design and the Hippers were 45% bigger, with less armour and similar armament.

Author:  smurf [ December 25th, 2014, 10:07 pm ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

You may be interested in RN thinking about 8in cruisers just before WWII.
First step was a range of designs of around 10,000tons. Waterline lengths set at 580ft by docking restrictions in overseas bases. Beam 66ft.
Design A with 3x3 8in was preferred. Secondaries 4x2 4in, AA 4x4 2pdr, 2x3 21inTT. 32knots from 80,000shp. Belt 5in, deck 2in. Armour weight was 1850tons.
That fits Krakatoa's comments on hull dimensions, and JSB's on uniform secondary battery. The reason for preferring 4in to 3.5in (90mm) is that medium calibre AA guns downed planes by shell fragments from near misses, rather than by direct hits. A 4in produced more fragments of optimum size, while there is little difference between 4in and 3.5in rate of fire.
That said, RN thinking moved on to a 12,500ton design for 32.5knots from 96,000shp and a 3in deck, then to 15,500tons from 125,000shp with 6x2 4in, and 6in belt. Armour weights 2400 and 3300tons respectively. Their hulls were bigger chiefly to fit more power for higher speed to catch enemy raiders, though none of these ships were built. Compare too USS Wichita (wl length 600ft) and Baltimore, with length/beam ratios nearer 10:1 and more power from higher pressure turbines.
I don't think you need a 7in+ belt to stop 8in shells, while it won't stop larger armour piercing shells, so you are better to accept 5 or perhaps 6in belt, and put the weight saved into deck armour to keep bombs out.

Author:  Psilander [ December 30th, 2014, 12:23 pm ]
Post subject:  Re: Heavy, post treaty cruiser, ca 1938

Thanks for your comments
I made some recalculations, a bit heavier, no 75mm battery, 33kts
Quote:
Uppland (Öland, Halland, Småland),
Sweden
Sweden Heavy Cruiser laid down 1937

Displacement:
11 006 t light; 11 567 t standard; 12 500 t normal; 13 246 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(619,19 ft / 606,96 ft) x 72,18 ft x (21,33 / 22,22 ft)
(188,73 m / 185,00 m) x 22,00 m x (6,50 / 6,77 m)

Armament:
9 - 8,27" / 210 mm 45,0 cal guns - 284,98lbs / 129,26kg shells, 150 per gun
Breech loading guns in turret on barbette mounts, 1937 Model
2 x 3-gun mounts on centreline ends, evenly spread
1 x 3-gun mount on centreline, aft deck centre
14 - 4,13" / 105 mm 45,0 cal guns - 35,62lbs / 16,16kg shells, 300 per gun
Quick firing guns in turret on barbette mounts, 1937 Model
6 x 2 row twin mounts on sides, evenly spread
2 raised mounts
1 x 2 row twin mount on centreline forward
1 raised mount
24 - 1,57" / 40,0 mm 60,0 cal guns - 2,14lbs / 0,97kg shells, 500 per gun
Anti-air guns in deck mounts, 1936 Model
12 x Twin mounts on centreline, evenly spread
12 raised mounts
Weight of broadside 3 115 lbs / 1 413 kg
Main Torpedoes
6 - 21,0" / 533 mm, 26,25 ft / 8,00 m torpedoes - 1,738 t each, 10,428 t total
In 2 sets of deck mounted side rotating tubes
Mines
2 - 661,39 lbs / 300,00 kg mines + 60 reloads - 18,306 t total
in Above water - Stern racks/rails

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 5,91" / 150 mm 393,70 ft / 120,00 m 10,20 ft / 3,11 m
Ends: 1,97" / 50 mm 196,85 ft / 60,00 m 10,20 ft / 3,11 m
16,40 ft / 5,00 m Unarmoured ends
Upper: 1,97" / 50 mm 393,70 ft / 120,00 m 8,01 ft / 2,44 m
Main Belt covers 100 % of normal length

- Hull void:
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: 3,94" / 100 mm 1,77" / 45 mm 1,77" / 45 mm
2nd: 1,77" / 45 mm 0,79" / 20 mm 0,79" / 20 mm
3rd: 0,20" / 5 mm - -

- Armoured deck - multiple decks:
For and Aft decks: 1,77" / 45 mm
Forecastle: 0,79" / 20 mm Quarter deck: 0,79" / 20 mm

- Conning towers: Forward 5,91" / 150 mm, Aft 5,91" / 150 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 2 shafts, 88 633 shp / 66 120 Kw = 32,00 kts
Range 7 500nm at 14,00 kts
Bunker at max displacement = 1 679 tons

Complement:
590 - 768

Cost:
£5,574 million / $22,297 million

Distribution of weights at normal displacement:
Armament: 923 tons, 7,4 %
- Guns: 879 tons, 7,0 %
- Weapons: 44 tons, 0,3 %
Armour: 2 668 tons, 21,3 %
- Belts: 1 397 tons, 11,2 %
- Armament: 256 tons, 2,0 %
- Armour Deck: 878 tons, 7,0 %
- Conning Towers: 137 tons, 1,1 %
Machinery: 2 457 tons, 19,7 %
Hull, fittings & equipment: 4 704 tons, 37,6 %
Fuel, ammunition & stores: 1 494 tons, 12,0 %
Miscellaneous weights: 275 tons, 2,2 %
- Hull below water: 100 tons
- Hull void weights: 25 tons
- Hull above water: 75 tons
- On freeboard deck: 50 tons
- Above deck: 25 tons

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
18 265 lbs / 8 285 Kg = 64,6 x 8,3 " / 210 mm shells or 1,6 torpedoes
Stability (Unstable if below 1.00): 1,21
Metacentric height 4,3 ft / 1,3 m
Roll period: 14,5 seconds
Steadiness - As gun platform (Average = 50 %): 55 %
- Recoil effect (Restricted arc if above 1.00): 0,40
Seaboat quality (Average = 1.00): 1,03

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and small transom stern
Block coefficient (normal/deep): 0,468 / 0,476
Length to Beam Ratio: 8,41 : 1
'Natural speed' for length: 26,71 kts
Power going to wave formation at top speed: 57 %
Trim (Max stability = 0, Max steadiness = 100): 53
Bow angle (Positive = bow angles forward): 25,00 degrees
Stern overhang: -3,28 ft / -1,00 m
Freeboard (% = length of deck as a percentage of waterline length):
Fore end, Aft end
- Forecastle: 15,00 %, 26,25 ft / 8,00 m, 22,97 ft / 7,00 m
- Forward deck: 60,00 %, 22,97 ft / 7,00 m, 19,69 ft / 6,00 m
- Aft deck: 10,00 %, 13,12 ft / 4,00 m, 13,12 ft / 4,00 m
- Quarter deck: 15,00 %, 13,12 ft / 4,00 m, 13,12 ft / 4,00 m
- Average freeboard: 19,72 ft / 6,01 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 88,0 %
- Above water (accommodation/working, high = better): 184,7 %
Waterplane Area: 29 045 Square feet or 2 698 Square metres
Displacement factor (Displacement / loading): 117 %
Structure weight / hull surface area: 123 lbs/sq ft or 600 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0,96
- Longitudinal: 1,45
- Overall: 1,00
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room

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