Logi's Design Studies

[Logi]

Bigger ship.

Minimalist Concept Study Tangent V5,  Battleship laid down 1925

Displacement:
   26,000 t light; 28,141 t standard; 29,456 t normal; 30,508 t full load

Dimensions: Length overall / water x beam x draught
   550.00 ft / 550.00 ft x 102.00 ft x 30.00 ft (normal load)
   167.64 m / 167.64 m x 31.09 m  x 9.14 m

Armament:
      16 - 14.00" / 356 mm guns (4x4 guns), 1,650.00lbs / 748.43kg shells, 1925 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 1 raised mount - superfiring
      20 - 5.00" / 127 mm guns (10x2 guns), 62.50lbs / 28.35kg shells, 1925 Model
     Quick firing guns in deck mounts with hoists
     on side, all amidships, 4 raised mounts - superfiring
      2 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1925 Model
     Anti-aircraft guns in deck mounts
     on centreline, all amidships
   Weight of broadside 27,677 lbs / 12,554 kg
   Shells per gun, main battery: 100

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   11.0" / 279 mm   395.00 ft / 120.40 m   17.03 ft / 5.19 m
   Ends:   2.00" / 51 mm   155.00 ft / 47.24 m   16.00 ft / 4.88 m
     Main Belt covers 110 % of normal length

   - Torpedo Bulkhead:
      1.50" / 38 mm   395.00 ft / 120.40 m   35.00 ft / 10.67 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   15.0" / 381 mm   5.30" / 135 mm      12.0" / 305 mm
   2nd:   2.00" / 51 mm   1.00" / 25 mm      2.00" / 51 mm
   3rd:   0.25" / 6 mm   0.25" / 6 mm            -

   - Armour deck: 2.59" / 66 mm, Conning tower: 3.00" / 76 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 36,006 shp / 26,861 Kw = 21.00 kts
   Range 8,000nm at 12.00 kts
   Bunker at max displacement = 2,367 tons

Complement:
   1,123 - 1,461

Cost:
   £11.496 million / $45.984 million

Distribution of weights at normal displacement:
   Armament: 2,904 tons, 9.9 %
   Armour: 8,890 tons, 30.2 %
      - Belts: 3,403 tons, 11.6 %
      - Torpedo bulkhead: 767 tons, 2.6 %
      - Armament: 2,667 tons, 9.1 %
      - Armour Deck: 1,991 tons, 6.8 %
      - Conning Tower: 62 tons, 0.2 %
   Machinery: 1,169 tons, 4.0 %
   Hull, fittings & equipment: 12,687 tons, 43.1 %
   Fuel, ammunition & stores: 3,456 tons, 11.7 %
   Miscellaneous weights: 350 tons, 1.2 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     27,670 lbs / 12,551 Kg = 20.2 x 14.0 " / 356 mm shells or 4.6 torpedoes
   Stability (Unstable if below 1.00): 1.09
   Metacentric height 6.1 ft / 1.9 m
   Roll period: 17.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.79
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.613
   Length to Beam Ratio: 5.39 : 1
   'Natural speed' for length: 23.45 kts
   Power going to wave formation at top speed: 48 %
   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 (% = measuring location as a percentage of overall length):
      - Stem:      16.00 ft / 4.88 m
      - Forecastle (20 %):   15.00 ft / 4.57 m
      - Mid (50 %):      15.00 ft / 4.57 m
      - Quarterdeck (15 %):   15.00 ft / 4.57 m
      - Stern:      15.00 ft / 4.57 m
      - Average freeboard:   15.08 ft / 4.60 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 110.4 %
      - Above water (accommodation/working, high = better): 105.6 %
   Waterplane Area: 41,515 Square feet or 3,857 Square metres
   Displacement factor (Displacement / loading): 85 %
   Structure weight / hull surface area: 236 lbs/sq ft or 1,151 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.94
      - Longitudinal: 1.64
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate

Deck covers only armored box (350 ft), thus real armor is 4" (102mm) over the 350 ft of the protected box.

Main belt sloped 20 degrees, vertical height is 16 ft. Main belt tapers from 13.5" at the top to 8.5" at the bottom. Main belt is 11" at waterline (LOS thickness 11.7").

Misc Weight (350 t):
250t FCS
25t Radar
25t Long Range Wireless
50 Construction Reserve

[Delta Force]

That design reminds me of the ships the French had planned during the 1910s. Unfortunately, this ship seems to be terribly prone to capsizing, even with only one turret raised. Also, considered using the 15 inch gun due to its greater range and armor penetration capabilities?

[Logi]

Unfortunately, this ship seems to be terribly prone to capsizing, even with only one turret raised.

And where exactly are you getting that? There is no reading at all that says such a thing.

Also, considered using the 15 inch gun due to its greater range and armor penetration capabilities?

The 14" superheavy has much better penetration capabilities than a 15".

[Jefgte]

167.64 m / 167.64 m x 31.09 m  x 9.14 m

Stability is actualy 1.09 ...not tip top.
Increase beam & reduce draught.
Increase beam (to 32m for ex.) is better too for T4x356.


Jef  ;)

[ctwaterman]

The 14" superheavy has much better penetration capabilities than a 15".

Only at short range or at long range and steep angles of Impact vs. Deck Armor.

At intermediate range the standard 15" shell with its much higher Muzzle Velocity will give better belt penetration.

Either that or I have completely missread the penetration data from a Navalweapon page.

The USN Super Heavy which your shell is obviously trying to copy gave up performance in once area to achieve better performance in another.  It was a compromise made by a navy that expected to engage in long range daylight shooting in the Pacific Ocean.

[Valles]

Also, the CSA's 2000-pounder is firing a pretty dang 'heavy' shell already.

[Delta Force]

Unfortunately, this ship seems to be terribly prone to capsizing, even with only one turret raised.

And where exactly are you getting that? There is no reading at all that says such a thing.

Also, considered using the 15 inch gun due to its greater range and armor penetration capabilities?

The 14" superheavy has much better penetration capabilities than a 15".

Well, I meant in reference to battle damage. The ship does seem to be vulnerable to capsizing after suffering underwater damage. But that may only be in reference to my design style with two meter thick torpedo blisters on each side. I have noticed that I am the only one using torpedo blisters on my designs, but my bulkhead strength itself does seem to be a tad lighter than those others use (2 inches, while I seen them up to 2.5 or 3.5 inches).

Also, while the 14 inch should be fine for a ship in close range, you have to keep in mind that this ship is only capable of 21 knots. An increasing number of ships are coming with heavier guns than that, and an increasing number of ships are going to have higher speeds than that. If you face a ship that is capable of keeping whatever distance it wants from you and that also has longer range guns like 15 inch, it isn't going to end well.

Now, if you can get close enough to a ship, the range starts to matter less and it just turns into a battle over who can throw out the most lead. At closer ranges, any modern naval gun can penetrate the thickest armor that can be produced, so you will be able to throw out more lead per gun and as a whole relative to a ship armed with the heavier guns. It's rather pre-dreadnought in concept, but it can work. That is, assuming that you can close enough to be able to punch through the enemies belt, which is probably going to be problematic.

[Logi]

Also, while the 14 inch should be fine for a ship in close range, you have to keep in mind that this ship is only capable of 21 knots. An increasing number of ships are coming with heavier guns than that, and an increasing number of ships are going to have higher speeds than that. If you face a ship that is capable of keeping whatever distance it wants from you and that also has longer range guns like 15 inch, it isn't going to end well.

It's difficult to aim outside of the range of a 14" simply because FCS are not up to par. Range differences are rather overstated here.

Now, if you can get close enough to a ship, the range starts to matter less and it just turns into a battle over who can throw out the most lead. At closer ranges, any modern naval gun can penetrate the thickest armor that can be produced, so you will be able to throw out more lead per gun and as a whole relative to a ship armed with the heavier guns. It's rather pre-dreadnought in concept, but it can work. That is, assuming that you can close enough to be able to punch through the enemies belt, which is probably going to be problematic.

With less guns but heavier guns, you are trading chance to land a hit for damage on a hit. A 16 x 14" can simply use HE until your ship is soft-killed. It has a much higher chance of hitting.

Also, the CSA's 2000-pounder is firing a pretty dang 'heavy' shell already.

I meant the standard 15".

The USN Super Heavy which your shell is obviously trying to copy gave up performance in once area to achieve better performance in another.  It was a compromise made by a navy that expected to engage in long range daylight shooting in the Pacific Ocean.

You are wrong. I was never trying to copy another naval gun when I made the 14" superheavy. I was simply trying to get more firepower on a smaller gun. Any similarities to the USN 16" superheavy is only a coincidence.

Stability is actualy 1.09 ...not tip top.

What? 1.10 is excess. 1.09 is ok. 1.08 is not tip top. 1.07 is bad. That is the scale I've always used.

Increase beam (to 32m for ex.) is better too for T4x356.

There is no need to increase beam. The BC is 0.613 and the beam is wide enough to support T4X14".

[Sachmle]

Stability is actualy 1.09 ...not tip top.
What? 1.10 is excess. 1.09 is ok. 1.08 is not tip top. 1.07 is bad. That is the scale I've always used.

I've always went with 1.10 as the minimum, but have allowed some fudging. Sometimes you'll get a 60% steadiness and a 1.09 stability, but rasing stability to 1.10 drops steadiness to 58%...kinda weird like that, so I'll settle for the 1.09 to keep the 60 instead of the 58.

I notice you have 1.09 and 51%, I'm gonna guess that raising the stability to 1.10 drops the steadiness to 48-49%, which is a situation where I'd settle for the 1.09.

[Kaiser Kirk]

Interesting.
A shorter Pennsylvania but with 5' more beam and Quads rather than triples. 
Only 1 raised mount is an interesting choice, but you don't really need em if you can't chase or run.

Considering that deck averaging isn't officially accepted, don't care for it.
Even counting it- you state a 350ft citadel, when the belt covers 395ft.

And lastly, the sheet RLBH/RA came up with in Wesworld gives a needed deck of 85.27 to make 102mm.
Can't see you're calculations, but the citadel is 70% of length, and  considering that the citadel is also the broadest part of the ship, providing 64% of the final 102mm armor doesn't seem correct.

[Logi]

Even counting it- you state a 350ft citadel, when the belt covers 395ft.

That's a mistake. I forgot to change the figures in the notes section, but the number in the deck value is always counted.

Can't see you're calculations, but the citadel is 70% of length, and  considering that the citadel is also the broadest part of the ship, providing 64% of the final 102mm armor doesn't seem correct.

? Citadel was never 70% of the ship. The ship needs as much space as given by the main belt length. The belt length dictates the coverage of the armored deck.

Hence:

Deck covers only armored box

The armored box is the coverage of the main belt. I don't know where you are getting 70% from.

Considering that deck averaging isn't officially accepted, don't care for it.

And lastly, the sheet RLBH/RA came up with in Wesworld gives a needed deck of 85.27 to make 102mm.

If you use SS3 and use it's break up of the decks, you get pretty much the same weight for the required thickness as I've simmed here. You may think differently but I place more trust in a program from the same creators for calculating such things than a sheet.

[Kaiser Kirk]

Can't see you're calculations, but the citadel is 70% of length, and  considering that the citadel is also the broadest part of the ship, providing 64% of the final 102mm armor doesn't seem correct.

? Citadel was never 70% of the ship. The ship needs as much space as given by the main belt length. The belt length dictates the coverage of the armored deck.

Hence:

Deck covers only armored box

The armored box is the coverage of the main belt. I don't know where you are getting 70% from.

Well, Main belt is 395 feet. Ship Length is 550 feet.
395/550 = 72%

[Logi]

Well, Main belt is 395 feet. Ship Length is 550 feet.
395/550 = 72%

Now I see what you were trying to say. Well, thank you for catching that mistake. You had me confused for a second there.

Well in any case, I upsized the large desgin by 2 kton. I've also made sure I didn't make that sort of mistake.

Minimalist Concept Study,  Light Battlecruiser laid down 1925

Displacement:
   28,000 t light; 30,196 t standard; 32,208 t normal; 33,818 t full load

Dimensions: Length overall / water x beam x draught
   550.00 ft / 550.00 ft x 102.00 ft x 31.00 ft (normal load)
   167.64 m / 167.64 m x 31.09 m  x 9.45 m

Armament:
      16 - 14.00" / 356 mm guns (4x4 guns), 1,650.00lbs / 748.43kg shells, 1925 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread, 1 raised mount - superfiring
      20 - 5.00" / 127 mm guns (10x2 guns), 62.50lbs / 28.35kg shells, 1925 Model
     Quick firing guns in deck mounts with hoists
     on side, all amidships, 4 raised mounts - superfiring
      2 - 3.00" / 76.2 mm guns in single mounts, 13.50lbs / 6.12kg shells, 1925 Model
     Anti-aircraft guns in deck mounts
     on centreline, all amidships
   Weight of broadside 27,677 lbs / 12,554 kg
   Shells per gun, main battery: 100

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   11.0" / 279 mm   370.00 ft / 112.78 m   17.03 ft / 5.19 m
   Ends:   3.00" / 76 mm   180.00 ft / 54.86 m   16.00 ft / 4.88 m
     Main Belt covers 103 % of normal length

   - Torpedo Bulkhead:
      1.50" / 38 mm   370.00 ft / 112.78 m   35.00 ft / 10.67 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   16.0" / 406 mm   7.00" / 178 mm      13.0" / 330 mm
   2nd:   2.00" / 51 mm   1.00" / 25 mm      2.00" / 51 mm
   3rd:   0.25" / 6 mm   0.25" / 6 mm            -

   - Armour deck: 4.26" / 108 mm, Conning tower: 3.00" / 76 mm

Machinery:
   Oil fired boilers, steam turbines,
   Direct drive, 2 shafts, 38,473 shp / 28,701 Kw = 21.00 kts
   Range 12,000nm at 12.00 kts
   Bunker at max displacement = 3,622 tons

Complement:
   1,201 - 1,562

Cost:
   £11.762 million / $47.048 million

Distribution of weights at normal displacement:
   Armament: 2,904 tons, 9.0 %
   Armour: 10,590 tons, 32.9 %
      - Belts: 3,398 tons, 10.5 %
      - Torpedo bulkhead: 719 tons, 2.2 %
      - Armament: 3,024 tons, 9.4 %
      - Armour Deck: 3,384 tons, 10.5 %
      - Conning Tower: 65 tons, 0.2 %
   Machinery: 1,249 tons, 3.9 %
   Hull, fittings & equipment: 12,810 tons, 39.8 %
   Fuel, ammunition & stores: 4,208 tons, 13.1 %
   Miscellaneous weights: 447 tons, 1.4 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     32,021 lbs / 14,524 Kg = 23.3 x 14.0 " / 356 mm shells or 5.2 torpedoes
   Stability (Unstable if below 1.00): 1.09
   Metacentric height 6.1 ft / 1.8 m
   Roll period: 17.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.78
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.648
   Length to Beam Ratio: 5.39 : 1
   'Natural speed' for length: 23.45 kts
   Power going to wave formation at top speed: 49 %
   Trim (Max stability = 0, Max steadiness = 100): 49
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      18.00 ft / 5.49 m
      - Forecastle (17 %):   16.00 ft / 4.88 m
      - Mid (50 %):      15.00 ft / 4.57 m
      - Quarterdeck (17 %):   15.00 ft / 4.57 m
      - Stern:      15.00 ft / 4.57 m
      - Average freeboard:   15.47 ft / 4.71 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 102.6 %
      - Above water (accommodation/working, high = better): 103.8 %
   Waterplane Area: 42,905 Square feet or 3,986 Square metres
   Displacement factor (Displacement / loading): 88 %
   Structure weight / hull surface area: 229 lbs/sq ft or 1,118 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.94
      - Longitudinal: 1.65
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate

Main Deck covers only armored box (370 ft), thus real armor is 4" (102mm) over the 370 ft of the protected box one deck under decklevel. At decklevel there is a 1.5" (38mm) weather deck running through the whole ship.

Main belt sloped 20 degrees, vertical height is 16 ft. Main belt tapers from 13.5" at the top to 8.5" at the bottom. Main belt is 11" at waterline (LOS thickness 11.7").

Misc Weight (350 t):
250t FCS
25t Radar
25t Long Range Wireless
50 Construction Reserve

[Logi]

Well, I meant in reference to battle damage. The ship does seem to be vulnerable to capsizing after suffering underwater damage.

That's in your imagination. That's the level of comparing a standard to the Richelieu and saying the Richelieu has a less robust underwater defense so it must capsize after an underwater hit. Yes, my design is less sturdy than your (larger) more armored ship, but it is not "terribly prone to capsizing".

But that may only be in reference to my design style with two meter thick torpedo blisters on each side. I have noticed that I am the only one using torpedo blisters on my designs, but my bulkhead strength itself does seem to be a tad lighter than those others use (2 inches, while I seen them up to 2.5 or 3.5 inches).

Very thick bulkheads are counter-productive. They cause more damage to the ship than it absorbs. That is why I try to use only 1.5" thick TDS. Other than actual things that happen when bulkheads are too thick, you can see yourself there is a huge diminishing return once you past 1" thick TDS in SS.

Also, I forgot why, but we hate Torpedo blisters here.

PS: That is also why I didn't increase the main belt thickness in my tapering designs. Simply because the end belt is reaching underwater into the TDS and as such a very thick metal in the TDS would be counterproductive. If possible, I would have calculated it with a taper belt from 13.5" (the upper limit) to something of the 1" variety, but it is difficult to do so.

[Kaiser Kirk]

1. Actually I use torpedo blisters as well, as that fits the development level of my naval designers.  Blisters do have negatives IRL* and P3D has observed SS2 doesn't do them right- I think his point is that adding blisters doesn't effect the ship's structural allocation properly. 

2. As for thickness- most people here sim the holding bulkhead alone.  The bulkheads separating internal compartments are not generally included. Perhaps they should, but they are not.   Interior bulkheads are not built from the same type of armor steel as the main belt, they are meant to deform greatly and then tear- not shatter.  As a result, thick single bulkheads are indeed undesirable as they are too thick to stretch instead of rupture. Plus historically the stiffer bulkheads in SoDak and Yamato had joint problems trying to balance the stretch/break issue.    To thin and you risk perforation by ejected parts of the hull and structure on the surface of the blast.



*Negatives include : gas bubble doesn't vent up as much, if void space then prone to off-center flooding, the wider they are, the further away from the belt a "short" round can enter the hull and dive inside the hull, and of course they slow down the vessel by increasing surface area.