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Real 'Large Light Cruisers'

What If Fisher had decided (or been forced ) to make real LLC not fake BCs ?



(couldn't really decide if 6 or 8 guns would fit best ?)

With hindsight this is the WNTs worse nightmare

JSB

this looks like quite a lot of wasted tonnage. both on the treaty scale and from a ship design perspective.

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I agree treaty wise (if it counts v capital ship tonnage).

But design wise ? I have simed a up armoured version (belt as early BCs is that to thick ? what would I want to stop 8inch/6inch treaty guns ?)

HMS C/G/F, GB LLC laid down 1915

Displacement:
17,677 t light; 18,426 t standard; 19,513 t normal; 20,383 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(786.00 ft / 786.00 ft) x 88.00 ft x (24.00 / 24.71 ft)
(239.57 m / 239.57 m) x 26.82 m x (7.32 / 7.53 m)

Armament:
6 - 9.45" / 240 mm 50.0 cal guns - 446.70lbs / 202.62kg shells, 150 per gun
Breech loading guns in turret on barbette mounts, 1915 Model
3 x Twin mounts on centreline ends, majority forward
1 raised mount - superfiring
14 - 5.50" / 140 mm 45.0 cal guns - 83.90lbs / 38.05kg shells, 200 per gun
Breech loading guns in deck mounts, 1915 Model
14 x Single mounts on sides, evenly spread
14 raised mounts
2 - 3.00" / 76.2 mm 45.0 cal guns - 13.62lbs / 6.18kg shells, 300 per gun
Anti-air guns in deck mounts, 1915 Model
2 x Single mounts on sides, forward deck aft
2 double raised mounts
Weight of broadside 3,882 lbs / 1,761 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 6.00" / 152 mm 510.00 ft / 155.45 m 12.00 ft / 3.66 m
Ends: Unarmoured
Main Belt covers 100 % of normal length

- Torpedo Bulkhead - Additional damage containing bulkheads:
2.00" / 51 mm 510.00 ft / 155.45 m 20.00 ft / 6.10 m
Beam between torpedo bulkheads 72.00 ft / 21.95 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 7.00" / 178 mm 4.00" / 102 mm 7.00" / 178 mm
2nd: 1.00" / 25 mm - -

- Armoured deck - single deck:
For and Aft decks: 3.00" / 76 mm
Forecastle: 0.00" / 0 mm Quarter deck: 2.00" / 51 mm

- Conning towers: Forward 7.00" / 178 mm, Aft 7.00" / 178 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 90,000 shp / 67,140 Kw = 30.21 kts
Range 4,000nm at 15.00 kts
Bunker at max displacement = 1,957 tons

Complement:
825 - 1,073

Cost:
£2.082 million / $8.329 million

Distribution of weights at normal displacement:
Armament: 845 tons, 4.3 %
- Guns: 845 tons, 4.3 %
Armour: 5,243 tons, 26.9 %
- Belts: 1,516 tons, 7.8 %
- Torpedo bulkhead: 755 tons, 3.9 %
- Armament: 650 tons, 3.3 %
- Armour Deck: 2,103 tons, 10.8 %
- Conning Towers: 219 tons, 1.1 %
Machinery: 3,409 tons, 17.5 %
Hull, fittings & equipment: 8,180 tons, 41.9 %
Fuel, ammunition & stores: 1,836 tons, 9.4 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
35,851 lbs / 16,262 Kg = 85.0 x 9.5 " / 240 mm shells or 5.6 torpedoes
Stability (Unstable if below 1.00): 1.27
Metacentric height 6.4 ft / 1.9 m
Roll period: 14.6 seconds
Steadiness - As gun platform (Average = 50 %): 75 %
- Recoil effect (Restricted arc if above 1.00): 0.30
Seaboat quality (Average = 1.00): 1.51

Hull form characteristics:
Hull has rise forward of midbreak,
a normal bow and a cruiser stern
Block coefficient (normal/deep): 0.411 / 0.417
Length to Beam Ratio: 8.93 : 1
'Natural speed' for length: 28.04 kts
Power going to wave formation at top speed: 44 %
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 %, 30.84 ft / 9.40 m, 25.23 ft / 7.69 m
- Forward deck: 50.00 %, 25.23 ft / 7.69 m, 25.23 ft / 7.69 m
- Aft deck: 15.00 %, 12.62 ft / 3.85 m, 12.62 ft / 3.85 m
- Quarter deck: 15.00 %, 12.62 ft / 3.85 m, 12.62 ft / 3.85 m
- Average freeboard: 21.90 ft / 6.67 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 90.2 %
- Above water (accommodation/working, high = better): 220.9 %
Waterplane Area: 42,874 Square feet or 3,983 Square metres
Displacement factor (Displacement / loading): 128 %
Structure weight / hull surface area: 140 lbs/sq ft or 684 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.99
- Longitudinal: 1.16
- Overall: 1.01
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room
Ship has slow, easy roll, a good, steady gun platform
Excellent seaboat, comfortable, can fire her guns in the heaviest weather

Do please point out any (of the) flaws

What would happen if these got built as LCAs ? How would the treaty's cope (I cant see the RN accepting them as BCs or scraping them) ?

JSB

This certainly makes more sense than four 15-inch or two 18-inch guns.

Still badly armored though...

On the other hand, with such a modest armament*, the commander of the vessel wouldn't be tempted to engage anything bigger than light cruisers, and for stopping light cruiser fire, 6" armour belt is plenty(as are the other factors).

*Btw, in the 'sharp it should show a 234 mm gun, not a 240 mm gun.

Yes, you have something in there, but those 9.2"/9.45" guns was at that time one of the longest ranged guns, but that most usable as artillery...

I'm not questioning his choice of gun, quite on the contrary. But in British service it was relined from 240 mm(the original caliber, ordered by Norway) to 234 mm caliber(resulting in a length of 51 calibers instead of 50) to allow it to use the standard 9,2" shells. The British navy has never used 240 mm guns, and didn't have a production chain for shells of that caliber. They did however have a greatly evolved one for 234 mm shells.

Sorry the spring sharp was just a quick one to think about belts and to put 3 or 4 turrets on her. (I would have liked maybe 8 guns for salvos at range)
They are the export guns relined for 9.2 and built in a new twin turret (or a new 9.2 with the same ish spec)

I quite like her, she could really hurt any none capital ships she meets and has speed to catch stuff. (She will be faster than sim 31.5KN as OTL)(and I think she is a much better balanced ship that the OTL ones)

What would happen at WNT I see a few options,

They are counted as BC ? - everybody get to keep more ships (but everybody else small ships are less useful ) ?
Everybody get to build some - cost money so unlikely
CA limit is raided to 9.2-10/11 inch and 20kt standard ? - will start an arms race but maybe ? ( CA and Cl are now much more spread out )
They are turned into CVs - boring.
They are scraped - over RN dead body.
They are forgotten about/grandfathered in - hum.
NO treaty ? - unlikely everybody wanted it to save money.

JSB

Howdy JSB,

The idea of putting multiple guns of the relined 9.4/9.2" on a battlecruiser/large cruiser hull is a good one. The Courageous type were the size they were because they needed the 81 feet of breadth to be able to mount the twin 15". The twin 9.4/9.2 do not need the same breadth and you can reduce the width to 73-75 which if you keep the same length-to-breadth ratio will give you a ship 708-727 feet long. That would save quite a bit in weight and allow you a 6" armour belt which will make your ship cruiser proof but 11" guns and up will go straight through. You would need 9-10" belt armour to stop the German 11-12" guns.

Definitely go for the 8 guns if you can make the numbers work. A 32 knot speed should be achievable with something around 90-100,000shp.

Nige

if 'regular size' cruisers can take 4 turrets, then this monster can take 4 too, that is for certain. other then that, I am with krakatoa, the hull shape dictated by the 15'' guns or even the 18'' guns of the furious can be optimised a lot if you go for smaller weapons, spread out over the hull. you might be able to reuse the machinery of regular heavy cruisers (or for example half a battleship plant) and keep the weights for that, and only increase the weight for the additional armour.

that, basically, was what I meant with the 'waste of displacement' comment earlier

_________________
Drawings are credited with J.Scholtens
I ask of you to prove me wrong. Not say I am wrong, but prove it, because then I will have learned something new.
Shipbucket Wiki admin