Regarding the calibre of this new ship.

I can understand the rational for wanting the heaviest guns possible but it really is a big push to get them into a ship of this required displacement.
If the calibre drops you can get more wiggle room for a better balanced ship. At some point someone will point out that a 12" gun, whilst not able to match a 15" or 16" in raw power is still able to severely damage most capital ships. Yes it wont win a fight against any Battle line ship but it can mission kill them by damaging vital equipment and has the advantage of placing limits on the Germans.

At some point someone will have to lay it out that you cant have a ship that does it all on the displacement available, their will have to be sacrifices. Designing a ship to a purpose, even if it is a secondary purpose is more likely to produce a useful and adaptable design than trying to design an adaptable ship to strict limits.

Is like practically trying to build another invincible all over again, but with the further disadvantaged that there are already ships that are able to hunt her and sink her with a scratch.

I just had a thought, correct me if I'm wrong. IIRC, the Germans can't put any new guns on their capital ships. The smallest British caliber at the moment is 13.5" or 34.3cm. German calibers at the moment are 12"/30.5cm and 13.8"/35cm, which is larger than the British 34.3cm gun, making it illegal. As long as the Germans aren't allowed to mount a new gun on their ships for the duration of the treaty, that means they are effectively limited to 12".

Yes, that's correct.
 
I just had a thought, correct me if I'm wrong. IIRC, the Germans can't put any new guns on their capital ships. The smallest British caliber at the moment is 13.5" or 34.3cm. German calibers at the moment are 12"/30.5cm and 13.8"/35cm, which is larger than the British 34.3cm gun, making it illegal. As long as the Germans aren't allowed to mount a new gun on their ships for the duration of the treaty, that means they are effectively limited to 12".

The Germans weren't invited to the WNT, so they should not have any restrictions on heavy gun development for naval and coastal defense purposes. They can't mount anything bigger than 13.5" due to the peace treaty limiting them to the smallest British capital ship gun, but they are free to develop a new 13.5" gun if they want.
 
The Germans weren't invited to the WNT, so they should not have any restrictions on heavy gun development for naval and coastal defense purposes. They can't mount anything bigger than 13.5" due to the peace treaty limiting them to the smallest British capital ship gun, but they are free to develop a new 13.5" gun if they want.

In theory that's allowed, if my reading of the Stockholm peace is right.
 
I just had a thought, correct me if I'm wrong. IIRC, the Germans can't put any new guns on their capital ships. The smallest British caliber at the moment is 13.5" or 34.3cm. German calibers at the moment are 12"/30.5cm and 13.8"/35cm, which is larger than the British 34.3cm gun, making it illegal. As long as the Germans aren't allowed to mount a new gun on their ships for the duration of the treaty, that means they are effectively limited to 12".

Yes, that's correct.

My understanding is the Germans are limited to no new capital ships until 1928 then they can build brand new as long as they don't exceed the British smallest calibre. I could be wrong though.

That's correct too

Both arguments are correct.

I think the first is actually incorrect, while the second is correct. The WNT signatories are barred from developing new heavy naval guns, so the most powerful guns are Furious' 18"/45 guns followed by the South Dakotas' 16"/50 guns. Germany isn't a WNT signatory, so it can develop new heavy guns. It is under the Stockholm limits so it can't deploy new heavy guns for land service (not coastal defense), but has no restrictions on developing new heavy guns for naval use.
 
I think the first is actually incorrect, while the second is correct. The WNT signatories are barred from developing new heavy naval guns, so the most powerful guns are Furious' 18"/45 guns followed by the South Dakotas' 16"/50 guns. Germany isn't a WNT signatory, so it can develop new heavy guns. It is under the Stockholm limits so it can't deploy new heavy guns for land service (not coastal defense), but has no restrictions on developing new heavy guns for naval use.

I misunderstood, sorry.
 
So some more mucking about in springsharp. I should add this is more to illustrate the points I have just been making, mainly that a ship designed well for one task is more adaptable than a ship designed to be adaptable but having no clear purpose. I dont think the British will end up with ships like this or that this is the direction the story will go. I do think the British will use one of my tricks though. So here we go.

I decided to look at a Battlecruisers concept primarily and see what I can push too. There were certain criteria I set that they had to meet.

Firstly 12" 50cal guns, The Brits already have these and once suitably "modernised" they should be rather good along with a new heavier, pointier 1000 pound shell. The 12" gun was chosen for a few reasons. The first is that its a lighter gun than the alternatives helping meet weight restrictions, Secondly lighter ammo for the same reason. Thirdly It limits the Germans to 12" guns.
I should note ammunition loads are kept low for the guns as per the precedent set so for. The design is in theory capble of carrying more rounds per gun
Secondly 32 knot speed, fast enough to close on any juicy targets whilst also being able to run from anything too big to fight.
Third long range, 8500nm so the ships can hunt around for targets and avoid heavy shipping lanes.

Once those have been met see how far you can push things.

HMS Lion, Great Britain Battlecruiser laid down 1926

Displacement:
19,906 t light; 20,589 t standard; 21,856 t normal; 22,869 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(690.26 ft / 680.00 ft) x 96.00 ft x (31.00 / 31.86 ft)
(210.39 m / 207.26 m) x 29.26 m x (9.45 / 9.71 m)

Armament:
6 - 12.00" / 305 mm 50.0 cal guns - 999.99lbs / 453.59kg shells, 60 per gun
Breech loading guns in turret on barbette mounts, 1926 Model
2 x 2-gun mounts on centreline, forward deck forward
1 raised mount - superfiring
1 x 2-gun mount on centreline, aft deck aft
12 - 4.50" / 114 mm 45.0 cal guns - 45.95lbs / 20.84kg shells, 150 per gun
Breech loading guns in turret on barbette mounts, 1926 Model
6 x Twin mounts on sides, evenly spread
Weight of broadside 6,551 lbs / 2,972 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 10.0" / 254 mm 380.00 ft / 115.82 m 12.00 ft / 3.66 m
Ends: Unarmoured
Upper: 4.00" / 102 mm 380.00 ft / 115.82 m 8.00 ft / 2.44 m
Main Belt covers 86 % of normal length
Main Belt inclined 12.00 degrees (positive = in)

- Torpedo Bulkhead - Strengthened structural bulkheads:
2.00" / 51 mm 400.00 ft / 121.92 m 28.00 ft / 8.53 m
Beam between torpedo bulkheads 86.00 ft / 26.21 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 10.0" / 254 mm 5.00" / 127 mm 9.00" / 229 mm
2nd: 1.00" / 25 mm 1.00" / 25 mm 1.00" / 25 mm

- Armoured deck - single deck:
For and Aft decks: 4.00" / 102 mm

- Conning towers: Forward 6.00" / 152 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 106,747 shp / 79,633 Kw = 32.00 kts
Range 8,500nm at 12.00 kts
Bunker at max displacement = 2,280 tons

Complement:
898 - 1,168

Cost:
£6.208 million / $24.833 million

Distribution of weights at normal displacement:
Armament: 1,461 tons, 6.7 %
- Guns: 1,461 tons, 6.7 %
Armour: 7,072 tons, 32.4 %
- Belts: 2,536 tons, 11.6 %
- Torpedo bulkhead: 829 tons, 3.8 %
- Armament: 1,112 tons, 5.1 %
- Armour Deck: 2,494 tons, 11.4 %
- Conning Tower: 101 tons, 0.5 %
Machinery: 3,417 tons, 15.6 %
Hull, fittings & equipment: 7,956 tons, 36.4 %
Fuel, ammunition & stores: 1,950 tons, 8.9 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
34,234 lbs / 15,528 Kg = 39.6 x 12.0 " / 305 mm shells or 5.6 torpedoes
Stability (Unstable if below 1.00): 1.33
Metacentric height 7.8 ft / 2.4 m
Roll period: 14.5 seconds
Steadiness - As gun platform (Average = 50 %): 47 %
- Recoil effect (Restricted arc if above 1.00): 0.28
Seaboat quality (Average = 1.00): 1.11

Hull form characteristics:
Hull has a flush deck,
a normal bow and large transom stern
Block coefficient (normal/deep): 0.378 / 0.385
Length to Beam Ratio: 7.08 : 1
'Natural speed' for length: 31.27 kts
Power going to wave formation at top speed: 53 %
Trim (Max stability = 0, Max steadiness = 100): 40
Bow angle (Positive = bow angles forward): 25.00 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 %, 22.00 ft / 6.71 m, 20.00 ft / 6.10 m
- Forward deck: 30.00 %, 20.00 ft / 6.10 m, 20.00 ft / 6.10 m
- Aft deck: 35.00 %, 20.00 ft / 6.10 m, 20.00 ft / 6.10 m
- Quarter deck: 15.00 %, 20.00 ft / 6.10 m, 20.00 ft / 6.10 m
- Average freeboard: 20.16 ft / 6.14 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 85.2 %
- Above water (accommodation/working, high = better): 174.4 %
Waterplane Area: 41,119 Square feet or 3,820 Square metres
Displacement factor (Displacement / loading): 110 %
Structure weight / hull surface area: 165 lbs/sq ft or 806 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.94
- Longitudinal: 1.85
- Overall: 1.00
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room

This first one is on the light side, only six main battery guns and twelve secondaries. It does have a 10" belt, a 4" deck and a 2" torpedo bulkhead so not too bad. All that for 20500 tons standard. This ship is more than capable of destroying any heavy cruiser that crosses its path whilst running from pretty much anything that can beat it in a head on fight.
Its not perfect though, 2500 tons shy of the displacement limit is a waste and that's before you look at adding 3000 tons for extra AA defence which the hull will struggle with slightly.

Lets see what else we can come up with


HMS Tiger, Great Britain Battlecruiser laid down 1926

Displacement:
23,630 t light; 24,625 t standard; 26,019 t normal; 27,134 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(693.06 ft / 680.00 ft) x 96.00 ft x (31.00 / 31.90 ft)
(211.24 m / 207.26 m) x 29.26 m x (9.45 / 9.72 m)

Armament:
9 - 12.00" / 305 mm 50.0 cal guns - 999.99lbs / 453.59kg shells, 80 per gun
Breech loading guns in turret on barbette mounts, 1926 Model
2 x 3-gun mounts on centreline, forward deck forward
1 raised mount - superfiring
1 x 3-gun mount on centreline, aft deck aft
16 - 4.50" / 114 mm 45.0 cal guns - 45.95lbs / 20.84kg shells, 150 per gun
Dual purpose guns in turret on barbette mounts, 1926 Model
8 x Twin mounts on sides, evenly spread
48 - 1.25" / 31.8 mm 60.0 cal guns - 1.07lbs / 0.49kg shells, 450 per gun
Anti-air guns in deck mounts, 1926 Model
12 x Quad mounts on centreline, evenly spread
Weight of broadside 9,787 lbs / 4,439 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 11.0" / 279 mm 450.00 ft / 137.16 m 12.00 ft / 3.66 m
Ends: Unarmoured
Upper: 4.00" / 102 mm 450.00 ft / 137.16 m 8.00 ft / 2.44 m
Main Belt covers 102 % of normal length
Main Belt inclined 12.00 degrees (positive = in)

- Torpedo Bulkhead - Strengthened structural bulkheads:
2.00" / 51 mm 550.00 ft / 167.64 m 30.00 ft / 9.14 m
Beam between torpedo bulkheads 84.00 ft / 25.60 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 11.0" / 279 mm 4.00" / 102 mm 9.00" / 229 mm
2nd: 1.00" / 25 mm 1.00" / 25 mm 1.00" / 25 mm

- Armoured deck - single deck:
For and Aft decks: 4.00" / 102 mm

- Conning towers: Forward 9.00" / 229 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 123,494 shp / 92,127 Kw = 32.00 kts
Range 8,500nm at 12.00 kts
Bunker at max displacement = 2,509 tons

Complement:
1,023 - 1,331

Cost:
£7.979 million / $31.918 million

Distribution of weights at normal displacement:
Armament: 2,198 tons, 8.4 %
- Guns: 2,198 tons, 8.4 %
Armour: 8,547 tons, 32.8 %
- Belts: 3,136 tons, 12.1 %
- Torpedo bulkhead: 1,221 tons, 4.7 %
- Armament: 1,394 tons, 5.4 %
- Armour Deck: 2,626 tons, 10.1 %
- Conning Tower: 170 tons, 0.7 %
Machinery: 3,953 tons, 15.2 %
Hull, fittings & equipment: 8,932 tons, 34.3 %
Fuel, ammunition & stores: 2,388 tons, 9.2 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
34,953 lbs / 15,854 Kg = 40.5 x 12.0 " / 305 mm shells or 5.6 torpedoes
Stability (Unstable if below 1.00): 1.20
Metacentric height 6.6 ft / 2.0 m
Roll period: 15.7 seconds
Steadiness - As gun platform (Average = 50 %): 53 %
- Recoil effect (Restricted arc if above 1.00): 0.46
Seaboat quality (Average = 1.00): 1.07

Hull form characteristics:
Hull has a flush deck,
a normal bow and large transom stern
Block coefficient (normal/deep): 0.450 / 0.456
Length to Beam Ratio: 7.08 : 1
'Natural speed' for length: 30.87 kts
Power going to wave formation at top speed: 56 %
Trim (Max stability = 0, Max steadiness = 100): 50
Bow angle (Positive = bow angles forward): 25.00 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 %, 28.00 ft / 8.53 m, 21.00 ft / 6.40 m
- Forward deck: 30.00 %, 21.00 ft / 6.40 m, 21.00 ft / 6.40 m
- Aft deck: 35.00 %, 21.00 ft / 6.40 m, 21.00 ft / 6.40 m
- Quarter deck: 15.00 %, 21.00 ft / 6.40 m, 23.00 ft / 7.01 m
- Average freeboard: 21.71 ft / 6.62 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 93.1 %
- Above water (accommodation/working, high = better): 169.1 %
Waterplane Area: 43,254 Square feet or 4,018 Square metres
Displacement factor (Displacement / loading): 103 %
Structure weight / hull surface area: 183 lbs/sq ft or 891 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.96
- Longitudinal: 1.91
- Overall: 1.03
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room

Now this is more like it. A total of Nine 12" guns in three turrets as well as sixteen 4.5" dual purpose secondaries. In addition to that you have an 11" belt, a 4" deck and a 2" torpedo bulkhead. All this for 24625 tons though. I'm pushing it here though, I have included 12 quad 1 pounder AA mounts the story has mentioned. This is a more complete design that yes does exceed the tonnage limit but not by much and some of the weight can be justified as extra AA additions. The ship also has more room to absorb extra weight increases.

Both these ships are good enough to smash heavy cruisers, they can cover a lot of Ocean should they need to "Hunt commerce raiders". In addition they can fight the majority of ships that can catch them whilst being able to outrun anything they cant fight. The guns they have can damage any ship afloat enough to mission kill them or make a pursuit undesirable. Finally should they need to be used in a fleet engagement they can ensure scouting information is denied to the enemy whilst allowing the British scouting info and being able to join in an already ongoing fleet engagement and harass and finish engaged or damaged ships. This is a far better use of the tonnage than trying to design a limited jack of all trades that cant really do anything, at least in my opinion.
 
Last edited:
What speed and belt can you get if you get if you take two of the Nelwoods' triple 16" turrets but with much-thinned gunhouse and barbette armour and use these new hoists, and put them both forward so they can chase down other battle cruisers?

After all, in a fleet action the turrets are much more expendable then a magazine or engineering space...
 
What speed and belt can you get if you get if you take two of the Nelwoods' triple 16" turrets but with much-thinned gunhouse and barbette armour and use these new hoists, and put them both forward so they can chase down other battle cruisers?

After all, in a fleet action the turrets are much more expendable then a magazine or engineering space...


This is what I got.

HMS Leopard, Great Britain Battlecruiser laid down 1926

Displacement:
25,612 t light; 26,865 t standard; 28,343 t normal; 29,526 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(633.99 ft / 620.00 ft) x 100.00 ft x (32.00 / 32.96 ft)
(193.24 m / 188.98 m) x 30.48 m x (9.75 / 10.05 m)

Armament:
6 - 16.00" / 406 mm 45.0 cal guns - 2,400.00lbs / 1,088.62kg shells, 80 per gun
Breech loading guns in turret on barbette mounts, 1926 Model
2 x 3-gun mounts on centreline, forward deck forward
1 raised mount - superfiring
12 - 4.50" / 114 mm 45.0 cal guns - 45.95lbs / 20.84kg shells, 150 per gun
Dual purpose guns in turret on barbette mounts, 1926 Model
6 x 2-gun mounts on sides, aft evenly spread
Weight of broadside 14,951 lbs / 6,782 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 12.0" / 305 mm 360.00 ft / 109.73 m 12.00 ft / 3.66 m
Ends: Unarmoured
Upper: 6.00" / 152 mm 360.00 ft / 109.73 m 8.00 ft / 2.44 m
Main Belt covers 89 % of normal length
Main Belt inclined 12.00 degrees (positive = in)

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 12.0" / 305 mm 6.00" / 152 mm 12.0" / 305 mm
2nd: 1.00" / 25 mm 1.00" / 25 mm 1.00" / 25 mm

- Armoured deck - multiple decks:
For and Aft decks: 4.00" / 102 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 107,442 shp / 80,152 Kw = 30.00 kts
Range 8,500nm at 12.00 kts
Bunker at max displacement = 2,661 tons

Complement:
1,091 - 1,419

Cost:
£8.933 million / $35.731 million

Distribution of weights at normal displacement:
Armament: 2,622 tons, 9.3 %
- Guns: 2,622 tons, 9.3 %
Armour: 7,690 tons, 27.1 %
- Belts: 3,103 tons, 10.9 %
- Armament: 1,978 tons, 7.0 %
- Armour Deck: 2,609 tons, 9.2 %
Machinery: 3,439 tons, 12.1 %
Hull, fittings & equipment: 11,860 tons, 41.8 %
Fuel, ammunition & stores: 2,731 tons, 9.6 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
35,424 lbs / 16,068 Kg = 17.3 x 16.0 " / 406 mm shells or 3.6 torpedoes
Stability (Unstable if below 1.00): 1.00
Metacentric height 5.0 ft / 1.5 m
Roll period: 18.7 seconds
Steadiness - As gun platform (Average = 50 %): 67 %
- Recoil effect (Restricted arc if above 1.00): 0.92
Seaboat quality (Average = 1.00): 1.01

Hull form characteristics:
Hull has a flush deck,
a normal bow and large transom stern
Block coefficient (normal/deep): 0.500 / 0.506
Length to Beam Ratio: 6.20 : 1
'Natural speed' for length: 29.63 kts
Power going to wave formation at top speed: 59 %
Trim (Max stability = 0, Max steadiness = 100): 67
Bow angle (Positive = bow angles forward): 25.00 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 %, 30.00 ft / 9.14 m, 22.00 ft / 6.71 m
- Forward deck: 30.00 %, 22.00 ft / 6.71 m, 22.00 ft / 6.71 m
- Aft deck: 35.00 %, 22.00 ft / 6.71 m, 22.00 ft / 6.71 m
- Quarter deck: 15.00 %, 22.00 ft / 6.71 m, 25.00 ft / 7.62 m
- Average freeboard: 22.87 ft / 6.97 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 78.0 %
- Above water (accommodation/working, high = better): 165.0 %
Waterplane Area: 42,958 Square feet or 3,991 Square metres
Displacement factor (Displacement / loading): 109 %
Structure weight / hull surface area: 215 lbs/sq ft or 1,049 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.90
- Longitudinal: 2.59
- Overall: 1.00
Excellent machinery, storage, compartmentation space
Excellent accommodation and workspace room

Just over 26500 tons standard with a 12" belt and only 30 knots. Its not bad but 2 triples forward is vulnerable and not really fast enough for its role. The armour isn't really up to a prolonged fight against 16" guns which begs the question why use 16" guns. The 16" is overkill for anything but fighting a Battleship but limits the design so much it cant really fight Battleships. You can go slower to increase protection say 26 knots so you can accompany the Nelwoods but even then you are still limited and if your building a ship to fight Battleships then build a Battleship. The ship really illustrates the point I was trying to make. You have to compromise somewhere if you are building to a limit.

Here is a well balanced 16" fast ship

HMS Vanguard, Great Britain Battleship laid down 1926

Displacement:
43,428 t light; 45,549 t standard; 47,595 t normal; 49,231 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
(820.00 ft / 820.00 ft) x 108.00 ft x (33.00 / 33.87 ft)
(249.94 m / 249.94 m) x 32.92 m x (10.06 / 10.32 m)

Armament:
9 - 16.00" / 406 mm 45.0 cal guns - 2,065.46lbs / 936.88kg shells, 100 per gun
Breech loading guns in turret on barbette mounts, 1926 Model
2 x 3-gun mounts on centreline, forward deck forward
1 raised mount - superfiring
1 x 3-gun mount on centreline, aft deck aft
20 - 4.50" / 114 mm 45.0 cal guns - 45.95lbs / 20.84kg shells, 250 per gun
Dual purpose guns in turret on barbette mounts, 1926 Model
10 x Twin mounts on sides, evenly spread
48 - 1.57" / 39.9 mm 60.0 cal guns - 2.12lbs / 0.96kg shells, 150 per gun
Anti-air guns in deck mounts, 1926 Model
12 x Quad mounts on centreline, evenly spread
Weight of broadside 19,610 lbs / 8,895 kg

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 14.0" / 356 mm 480.00 ft / 146.30 m 12.00 ft / 3.66 m
Ends: Unarmoured
Upper: 8.00" / 203 mm 480.00 ft / 146.30 m 8.00 ft / 2.44 m
Main Belt covers 90 % of normal length
Main Belt inclined 12.00 degrees (positive = in)

- Torpedo Bulkhead - Additional damage containing bulkheads:
2.00" / 51 mm 600.00 ft / 182.88 m 35.00 ft / 10.67 m
Beam between torpedo bulkheads 94.00 ft / 28.65 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 14.0" / 356 mm 8.00" / 203 mm 14.0" / 356 mm
2nd: 1.50" / 38 mm 1.50" / 38 mm 1.50" / 38 mm

- Armoured deck - multiple decks:
For and Aft decks: 6.00" / 152 mm

- Conning towers: Forward 9.00" / 229 mm, Aft 0.00" / 0 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 179,542 shp / 133,939 Kw = 32.00 kts
Range 8,500nm at 12.00 kts
Bunker at max displacement = 3,682 tons

Complement:
1,610 - 2,094

Cost:
£14.349 million / $57.398 million

Distribution of weights at normal displacement:
Armament: 3,932 tons, 8.3 %
- Guns: 3,932 tons, 8.3 %
Armour: 16,300 tons, 34.2 %
- Belts: 4,856 tons, 10.2 %
- Torpedo bulkhead: 1,554 tons, 3.3 %
- Armament: 3,666 tons, 7.7 %
- Armour Deck: 5,969 tons, 12.5 %
- Conning Tower: 255 tons, 0.5 %
Machinery: 5,747 tons, 12.1 %
Hull, fittings & equipment: 17,449 tons, 36.7 %
Fuel, ammunition & stores: 4,167 tons, 8.8 %
Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
65,892 lbs / 29,888 Kg = 32.2 x 16.0 " / 406 mm shells or 9.8 torpedoes
Stability (Unstable if below 1.00): 1.12
Metacentric height 7.0 ft / 2.1 m
Roll period: 17.2 seconds
Steadiness - As gun platform (Average = 50 %): 55 %
- Recoil effect (Restricted arc if above 1.00): 0.67
Seaboat quality (Average = 1.00): 1.10

Hull form characteristics:
Hull has a flush deck,
a normal bow and large transom stern
Block coefficient (normal/deep): 0.570 / 0.574
Length to Beam Ratio: 7.59 : 1
'Natural speed' for length: 33.15 kts
Power going to wave formation at top speed: 54 %
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 %, 35.00 ft / 10.67 m, 24.00 ft / 7.32 m
- Forward deck: 30.00 %, 24.00 ft / 7.32 m, 24.00 ft / 7.32 m
- Aft deck: 35.00 %, 24.00 ft / 7.32 m, 24.00 ft / 7.32 m
- Quarter deck: 15.00 %, 24.00 ft / 7.32 m, 26.00 ft / 7.92 m
- Average freeboard: 25.03 ft / 7.63 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 85.5 %
- Above water (accommodation/working, high = better): 186.2 %
Waterplane Area: 65,593 Square feet or 6,094 Square metres
Displacement factor (Displacement / loading): 105 %
Structure weight / hull surface area: 212 lbs/sq ft or 1,034 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.96
- Longitudinal: 1.44
- Overall: 1.00
Adequate machinery, storage, compartmentation space
Excellent accommodation and workspace room

Just shy of 46000 tons 32 knots, 14" belt, 6" deck and 3 16" guns. But she is a big lady and she needs to be to perform like this. Everything is a compromise unless you dont need to and then you pay a different price.
 
Just shy of 46000 tons 32 knots, 14" belt, 6" deck and 3 16" guns. But she is a big lady and she needs to be to perform like this. Everything is a compromise unless you dont need to and then you pay a different price.
That really shows how much displacement an extra couple knots from 30 to 32 costs, the Lion was a 30-knotter on ~41000 tons, this is similar to a 32 knot Lion, not far from an Iowa, actually, and it's 4000 tons heavier than a slightly slower Lion
 
That really shows how much displacement an extra couple knots from 30 to 32 costs, the Lion was a 30-knotter on ~41000 tons, this is similar to a 32 knot Lion, not far from an Iowa, actually, and it's 4000 tons heavier than a slightly slower Lion

Yep speed means weight, which is why ive been going on about 12" battlecruisers for way too long in this tread now tbh. Plus the design has no real room to grow or expand its right at the limit. You can either strengthen if you add weight affecting sea keeping quite a bit or avoid it and your still slightly wet but have also stressed the hull a lot.
 
A man named C.Coles with an off-the-wall idea about turrets. This worked SO well last time...
Possibly even more worrying; Cole's ideas about turrets were good (in that most turrets since have been derived from them, plus a lot of other stuff such as cranes and turntables).
Other the other hand, a man called Coles in charge of the design of a ship ...
 
Have they looked at a transom stern yet? its one way they can offset the need for a wider hull because of triple turrets. Has the added benefit of making a ship better able to have deep torpedo defences as well.
Yes, the story's Nelsons have transom sterns, and whatever they end up with here undoubtedly will too.
 
My question had I been in that meeting would be "Whats it for?"
Seems to be a Battlecruiser type design so commerce protection/raiding and heavy scouting. Thing is because it needs to use Battleship tonnage then they also want it to be able to stand up to a true capital ship to some degree. I get the impression it either needs to be able to withstand enough to enable it to run away or help with tipping the numbers in a fleet engagement by engaging already engaged ships or finishing off damaged ones.

Seems a big ask but that's just my interpretation of the post.
...

In TTL's 1920s, there are effectively 4 roles for a big-gun capital ship:
The first is the basic line-of-battle ship, which fights in the line of battle, against the opposing line of battle, and doesn't need the speed to do more than keep her place in the line.
The second is the "fast wing of the battleline", which has the necessary speed margin to force engagements, chase down fleeing enemies and maneuver for tactical advantage during a battle, but is still expected to slug it out with battleships.
The third is the "heavy scout", which supports the cruiser screen and hence needs cruiser speed. It's there to kill cruisers, not to fight battleships. In a fleet battle it will be hanging round the edges, waiting for a chance to finish off damaged or isolated enemies.
The fourth is the "detached raider/hunter", which is sent out into disputed sea to hunt down enemy cruisers (or commerce). Speed is essential, armour is only necessary against heavy-cruiser fire and its response to sighting "real" battleships is to head for the nearest horizon.

The problem is, as the RN found out in WW1, if your ship packs battleship-calibre armament, it will be pressed into the second role in service, no matter how hard the designer insists that it was built for roles 3 & 4. You don't spend all that money bringing a 15" broadside to the fight and then not use it. Which is why the RN is now discussing armouring their "light battlecruiser" against 14" fire. Which can't be legitimately done within Treaty limits.

If all they want is something to kill CAs, then dropping the main armament to 12" or even 10" solves most of their weight problems and probably makes a more effective cruiser-killer. If they want it to face 14" (let alone 16") fire they should accept they're building a fast battleship and 30+ knot speed is to much to ask for. RIght now, they seem to be heading between stools - too weak to fight battleships, too slow to catch cruisers & too expensive to leave home. Which is probably why they're discussing ... radical ... approaches to the weight issue.
They're conceived as cruiser-killers, to help render the big cruisers unnecessary (at least for the RN).
So their primary mission is still 3 & 4, like the old battlecruisers.
Stavanger may not have been a traumatic as Jutland (hence the battlecruiser being rather more reputable), but they've learned a bit from the war too. Anything with heavy guns (I'd call that 12"+ in this context) is going to end up facing a battleship someday - whether by accident or necessity.
This ship therefore needs to be 'safe' to do some of 2 as well - meaning it needs some level of protection against battleship fire.

The French and Italian light battleships were fairly well balanced, whereas the USN and this RN designs will follow more of a 'big navy' view of a light battleship - they're not seen as the best ships in the fleet, they are only there to support the real battlefleet, either directly in battle or by distracting the enemy with a powerful ship in an inconvenient place.
 
This is what I got.

HMS Leopard, Great Britain Battlecruiser laid down 1926
Displacement: 25,612 t light; 26,865 t standard; 28,343 t normal; 29,526 t full load

Just over 26500 tons standard with a 12" belt and only 30 knots. Its not bad but 2 triples forward is vulnerable and not really fast enough for its role. The armour isn't really up to a prolonged fight against 16" guns which begs the question why use 16" guns. The 16" is overkill for anything but fighting a Battleship but limits the design so much it cant really fight Battleships. You can go slower to increase protection say 26 knots so you can accompany the Nelwoods but even then you are still limited and if your building a ship to fight Battleships then build a Battleship. The ship really illustrates the point I was trying to make. You have to compromise somewhere if you are building to a limit.

I mentioned the 16" because the triple turrets are available. The last update suggestedthat the new design had to use an established turret design. Triple 15" would work okay, but I don't think they exist?

The design isn't there to fight battleships - it's there to kill cruisers, battle cruisers and to be able to contribute in a fleet fight, just not as part of the battle line. The 12" designs fail heavily on the last point.
 
I mentioned the 16" because the triple turrets are available. The last update suggestedthat the new design had to use an established turret design. Triple 15" would work okay, but I don't think they exist?

The design isn't there to fight battleships - it's there to kill cruisers, battle cruisers and to be able to contribute in a fleet fight, just not as part of the battle line. The 12" designs fail heavily on the last point.

The problem is which contributes more, a 16" gun ship that can inflict some damage, but has marginal survivability and will probably get taken out if the battle lasts more than 15 minutes, or a 12"-13.5" ship that will not contribute as much damage, but can actually last more than 15 minutes in action with opposing battleships? I agree it is a tricky question.
 
I mentioned the 16" because the triple turrets are available. The last update suggestedthat the new design had to use an established turret design. Triple 15" would work okay, but I don't think they exist?

The design isn't there to fight battleships - it's there to kill cruisers, battle cruisers and to be able to contribute in a fleet fight, just not as part of the battle line. The 12" designs fail heavily on the last point.

How does the 12" ship fail at supporting a battle fleet but not in the battle line?. It can crush any cruiser scouting for the fleet and match any Light battleship as they are either less well armoured or comparable but wit fewer guns. There are more uses for these ships than fleet engagements as well. Interwar the Royal Navy was looking at aggressive commerce raiding as a way to buy time for any fleet to get from its base to where it is needed wherever on the planet that is. The 12" ships are ideal for that role in a way any 16" ship isn't. then when the fleet arrives they have durable, fast scouts that either match their direct competition or are over match to lesser ships. If they fulfil their role of denying scouting for the enemy fleet they have done their job and supported the Battle line. It may be better than that as they may have been able to draw some capital ships out to look for them during the battle swinging things in the Royal Navy's favour significantly. Then if the fleets do meet and its line ahead for them both the ships can join in and engage already engaged ships or cross the T, they have the armour to fight at range whilst having guns large enough to cause issues in combination with bigger ships.

I just dont understand your complaint, you want ships that can do things that arent fighting in a battle line yet you want guns so large they limit the design of the ship or mean it has to be involved in the battle line? What roles where you thinking of in a fleet engagement are the ships meant to fill that dont include fighting in a battle line that the 12" ships cant do? They at least match the French and Italian ships, The Lexington's are much larger but poorly armoured whereas the Columbia's are slower and poorly protected. Yes they have larger guns but they are matched by the protection of the proposed ships. At longer ranges I would actually bet on the Royal Navy ships due to their heavier Deck and Turret armour. If you are comparing the capabilities of a necessarily limited ship to unlimited ships like the Lexingtons for instance then they will always fall short no matter what you try and do.
 
The problem is which contributes more, a 16" gun ship that can inflict some damage, but has marginal survivability and will probably get taken out if the battle lasts more than 15 minutes, or a 12"-13.5" ship that will not contribute as much damage, but can actually last more than 15 minutes in action with opposing battleships? I agree it is a tricky question.

Not really in my opinion at least. If you design a glass cannon it is vulnerable in whatever role you put it in. A more balanced design will be very useful in its intended roles whilst offering utility in other roles. The 12" ship is not intended to engage Battleships unless their is no other alternatives. If its in that situation then things are either really dire and bigger guns wont help or are going so well you dont need the bigger guns. Allow me to explain. The 12" ships have ensured the enemy has been denied scouting and allowed the RN fleet to cross the enemies T, the ships have done their job. Now they can get involved in the fleet action supporting the battleships and whilst they might not do major damage they can harass and damage important systems like fire control etc. Plus they have more utility in commerce raiding, something the RN was all about inter war as a way of buying time to get their fleet to where it needs to be. A glass cannon can be mission killed relatively easily whereas a ship that is more survivable can better fulfill that role.
 
Not really in my opinion at least. If you design a glass cannon it is vulnerable in whatever role you put it in. A more balanced design will be very useful in its intended roles whilst offering utility in other roles. The 12" ship is not intended to engage Battleships unless their is no other alternatives. If its in that situation then things are either really dire and bigger guns wont help or are going so well you dont need the bigger guns. Allow me to explain. The 12" ships have ensured the enemy has been denied scouting and allowed the RN fleet to cross the enemies T, the ships have done their job. Now they can get involved in the fleet action supporting the battleships and whilst they might not do major damage they can harass and damage important systems like fire control etc. Plus they have more utility in commerce raiding, something the RN was all about inter war as a way of buying time to get their fleet to where it needs to be. A glass cannon can be mission killed relatively easily whereas a ship that is more survivable can better fulfill that role.

Fair enough, I was mainly trying to point out King Augeas that the 16" guns have drawbacks as well as advantages. At 23(26),000 tons, a ship with 2 triple 16" turret is IMHO either going to be too slow to kill cruisers or too lightly armored to last in more than a few minutes in an engagement with capital ships. Ships with 12" or 14" guns can be fast enough to catch cruisers and can carry enough armor to survive a while, with the 14" better able to inflict damage and the 12" having more armor and greater survivability.

I suppose some navies might want a 25-26 knot 16" light battleship that can serve as a second rate battleship in an actual fleet battle, but can not catch cruisers. I
 
How does the 12" ship fail at supporting a battle fleet but not in the battle line?

Because 12" isn't enough to really scare enemy battleships yet it denies tonnage to the battle line. It's great to have as a scout to punch through the enemy's screen, but not at the cost of hobbling your own battle line.

Now, I agree that 16" is too much - I only mentioned it because I remembered that there was a triple 16" turret available and the demands of tonnage and sufficient guns for spotting favours two triple turrets. These things are using battleship tonnage and must be capable of harming enemy battleships - and 12" just doesn't cut it.

The question of:

The problem is which contributes more, a 16" gun ship that can inflict some damage, but has marginal survivability and will probably get taken out if the battle lasts more than 15 minutes, or a 12"-13.5" ship that will not contribute as much damage, but can actually last more than 15 minutes in action with opposing battleships? I agree it is a tricky question.

Is the wrong formulation - these things must be both survivable and threatening. And fast. And, presumably, have a mast to which the Moon could be attached too. :p
It's not easy and huge compromises will have to be made - hence focusing armour on magazines and engineering at the expense of turrets and particularly gunhouses, both in terms of numbers and armour.
 
Top