Design Bureau Guangzhou

[maddox]

Hey, Agincourt, but different.

[Jefgte]

...Main Belt covers 91 % of normal length...

You could certainly have the same ship in a 220m hull if you increase the BC to 0.6 & the draught.


Jef

[Logi]

Proof against it's own guns from the range of ~9000 yds to 20,920 yds.
Proof against the DKB 15" 750kg shell from the range of 9,870 yds to 21,420 yds.

Btw, remarkably similar performance for the shells!

Project 938 Guangzhou, RRC Battleship laid down 1924

Displacement:
   35,000 t light; 37,000 t standard; 38,630 t normal; 39,934 t full load

Dimensions: Length overall / water x beam x draught
   735.00 ft / 721.00 ft x 110.00 ft x 28.50 ft (normal load)
   224.03 m / 219.76 m x 33.53 m  x 8.69 m

Armament:
     16 - 14.00" / 356 mm guns (4x4 guns), 1,650.00lbs / 748.43kg shells, 1924 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 2 raised mounts - superfiring
     20 - 4.72" / 120 mm guns (10x2 guns), 50.00lbs / 22.68kg shells, 1924 Model
     Quick firing guns in deck mounts with hoists
     on side, all amidships
   Weight of broadside 27,400 lbs / 12,428 kg
   Shells per gun, main battery: 80

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   13.0" / 330 mm   465.00 ft / 141.73 m   13.10 ft / 3.99 m
   Ends:   Unarmoured
     Main Belt covers 99 % of normal length

  - Torpedo Bulkhead:
      2.50" / 64 mm   465.00 ft / 141.73 m   23.00 ft / 7.01 m

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   14.0" / 356 mm   8.00" / 203 mm      10.0" / 254 mm
   2nd:   2.00" / 51 mm   1.00" / 25 mm      1.00" / 25 mm

  - Armour deck: 3.40" / 86 mm, Conning tower: 5.00" / 127 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 87,773 shp / 65,479 Kw = 26.00 kts
   Range 8,000nm at 12.00 kts
   Bunker at max displacement = 2,935 tons

Complement:
   1,377 - 1,791

Cost:
   £12.504 million / $50.016 million

Distribution of weights at normal displacement:
   Armament: 2,876 tons, 7.4 %
   Armour: 11,273 tons, 29.2 %
      - Belts: 3,462 tons, 9.0 %
      - Torpedo bulkhead: 989 tons, 2.6 %
      - Armament: 3,056 tons, 7.9 %
      - Armour Deck: 3,642 tons, 9.4 %
      - Conning Tower: 123 tons, 0.3 %
   Machinery: 2,891 tons, 7.5 %
   Hull, fittings & equipment: 17,628 tons, 45.6 %
   Fuel, ammunition & stores: 3,630 tons, 9.4 %
   Miscellaneous weights: 332 tons, 0.9 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     44,925 lbs / 20,378 Kg = 32.7 x 14.0 " / 356 mm shells or 7.1 torpedoes
   Stability (Unstable if below 1.00): 1.09
   Metacentric height 6.8 ft / 2.1 m
   Roll period: 17.7 seconds
   Steadiness   - As gun platform (Average = 50 %): 58 %
         - Recoil effect (Restricted arc if above 1.00): 0.81
   Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.598
   Length to Beam Ratio: 6.55 : 1
   'Natural speed' for length: 26.85 kts
   Power going to wave formation at top speed: 49 %
   Trim (Max stability = 0, Max steadiness = 100): 57
   Bow angle (Positive = bow angles forward): 35.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      20.00 ft / 6.10 m
      - Forecastle (25 %):   19.00 ft / 5.79 m
      - Mid (50 %):      19.00 ft / 5.79 m
      - Quarterdeck (10 %):   19.00 ft / 5.79 m
      - Stern:      20.00 ft / 6.10 m
      - Average freeboard:   19.15 ft / 5.84 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 99.0 %
      - Above water (accommodation/working, high = better): 152.2 %
   Waterplane Area: 57,907 Square feet or 5,380 Square metres
   Displacement factor (Displacement / loading): 96 %
   Structure weight / hull surface area: 235 lbs/sq ft or 1,148 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.22
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent

[Sachmle]

1) Why compare to Me? Plan on war?

2) Your's is laid down 4yrs after mine, so mine in service 1 yr before your's starts

3) If your 13" belt/3.4" deck are proof then my 15" belt/4" deck are too

4) You have no end or upper belts. Bow hits flood like a mofo and hits above the belt will wreck your secondary magazines.

5) I hate quads.

[Logi]

1) No, it's just that your design was the further up thread that contained a battleship design. :D
2) Yea, I did it to fudge on the engine.
3) 4" deck? Last I read your Deck is 3.54"/90mm. And my Belt is inclined 20 degrees, yours 10 degrees? But you are right, both are immune to each other.

4) If I were to compare ships, I have twice the number of barrels, thus twice the chance to make hits. Thin end or upper belt will be shredded by BB fire anyways.

5) I know you do, I love them.

Basically it's fun to compare similar tonnage ships. I basically gave up speed and protection to have excessive firepower.

[Valles]

What would you rate her immune zone as vs. the Confederate model 15" 2,000 lb Heavy type shells? Or, for that matter, her guns' effectiveness against Cross Mirage's 380mm @ 20 belt and 120mm deck?

[Logi]

For Project 938, the immunity zone is somewhere: ~11,600 yds - 19,450 yds.

For Cross Mirage ~9000 yds - ~25,500yds

Assuming your solid is a single deck.

Cross Mirage really has too much armor, both for the Belt and the Deck. 15" inclined 20 degrees is quite overkill.

[Sachmle]

What would you rate her immune zone as vs. the Confederate model 15" 2,000 lb Heavy type shells?

The CSA 15" is only an 40cal gun so the MV will be low. Assuming 2100fps the Chinese ship is safe from 12,240yds out to 15,750yds.

[Logi]

Ah I didn't know it was a 40cal gun.

[Sachmle]

Ah I didn't know it was a 40cal gun.

Yes, quite the antique.

[Logi]

Ok I calculated the Muzzle Energy and from there figured out the Muzzle Velocity.

CSA 15"/40 Gun 2000lb shell. 2323.79FPS.

So Cross Mirage's immunity zone is roughly: 5,000 yds - 22,500 yds.

The Project 938 immunity zone is roughly: 8,000 yds - 17,810 yds.

It seems 13" inclined at 20 degrees is enough for most battles, though one would go 13.5" inclined at 20 degrees for protection against 16" shells. The real different between the two ships is the thickness of the deck armor.

4.7" vs 3.4", the Cross Mirage is a 1.3" advantage in thickness over the Project 938 resulting in a ~4,690 yds difference in immunity zones.

[Logi]

Sorry slight mistake. I forgot to re-calculate the muzzle velocity of my guns due to the increased shell weight for the caliber.

The Project 938
Proof against it's own guns from the range of ~7,500 yds to 19,940 yds.
Proof against the DKB 15" 750kg shell from the range of 9,870 yds to 21,420 yds.

We see here the main difference between the shells. The 14" Superheavy exchanges ~2,370 yds of belt penetration for ~1,480 yds of deck penetration. In other words, the Superheavy is a better deck penetrator than the DKB 15" but a worse belt penetrator.

[Sachmle]

Of course. The higher MV of my lighter shell will cause a flatter trajectory which will improve belt penetration anyway.

[ctwaterman]

Frowns at Logi's 356mm/L50 and notices it is the same gun Italia is using.  The One the British built for the Russians with the Heavy AP round to make it almost as effective as the British 15"/42

All told you designed a ship using the old Tripod of Guns, Speed, Armor... you sacrafice from one or more to increase the other.

I would comment that if your ships belt is Inclined at a 20 Degree slant then you really need to increase its height, others have pointed out to me that slanted belts take up more weight and have to be slightly taller to cover the same volume of space.  Your Belt is only 3.99m tall while your ship is 5.79m something here is exposed.  ;)  And its more then you front and rear end ???

[Valles]

Cross Mirage's barbettes - and really her entire design - are rated to fire rather greater guns than were available when she was first drawn up in 1912. Her armor suite and mount bracing are designed to cope with 400mm/L60 900kg guns, or defend against somewhat shorter 16-18 inch guns. The CSA's 'Fifteen-Inch Heavy Bore', as I think of it, took about the same magazine weight and was easily available at that point, but I've always intended the design as being rated to take new, nastier guns on essentially a 'plug and play' basis.

The fact that Richmond's terms mean no realistic battleship can afford to carry the kind of weapons that it'd take to threaten her protection is, if anything, serendipity - taking her from 'formidable' to 'outright nightmare'. Certainly, I could've shaved at least four thousand tons off of her total weight if I'd gone with a more conventionally balanced armor scheme, but I consider the additional margin of durability to be worth the price of a light cruiser - come to that, if the Mods had considered it technically feasible, her belt would've been even thicker.

That said, 938 has the speed to get inside CM's immunity zone with ease, and more than half-again as many chances to hit, so, in current configuration, I'd actually give her decent odds. Phrased in terms of what to expect compared with a ship something like six-to-ten years younger, I consider 'anybody's game' to be quite satisfactory.