## Friday, December 31, 2004

### I must confess that I had trouble fitting the machinery into the available space

### OK, so I have been experimenting with a small CL

### A larger DL or small CL

### I highly recommend 1/600 scale for doing ship drawing

### I ran my big US destroyer design

### Destroyers for War in the Pacific

## Wednesday, December 29, 2004

### Super-Destroyers

## Tuesday, December 28, 2004

### Cruiser design patterns

## Monday, December 27, 2004

### President Roosevelt was interested in having a ship like the French super-destroyers

## Sunday, December 26, 2004

### The 12-7.5in gun cruiser design works

### A cruiser with 12-7.5in/50 guns would make sense

## Friday, December 24, 2004

### Calculating the rudder post position

### I just ran my program for my 9.2in/50 gunned cruiser

### I still believe that there is room for a 9.2in gun ship for the 1921 building program

## Thursday, December 23, 2004

### In the early 1900's William Hovgaard suggested that the best battleship would be large and fast, with good armor and guns

## Wednesday, December 22, 2004

### Battleships and Battlecruisers

## Tuesday, December 21, 2004

### SpringSharp

## Monday, December 20, 2004

### WWII-era cruisers were largely "belted cruisers"

## Sunday, December 19, 2004

### An amusing exercise: "modernizing ironclads"

### I am pushing the upper limits on ship size

### The very large battleship design

I found out that the very large battleship, at higher speeds had a Reynolds number on the order of 5.6x10^9. My Schoenherr table, before this morning, only had values up to 4.999x10^9. I extended the table, and that solved the problem I was seeing last night. I had to turn on some printing so that I could see what was happening and what I needed to do to fix the problem. For Reynolds numbers above 5.0x10^9, the frictional resistance ended up as zero.

I can see now how I can improve the modeling of superstructure, so that I can get better stability calculation results. I also need to account for the heavy rangefinder and main battery fire control director mounted very high on a tower mast.

## Saturday, December 18, 2004

### The optimal super-large battleship

## Friday, December 17, 2004

### Cruisers and torpedoes

## Thursday, December 16, 2004

### Is there any benefit to speed in large ships?

## Wednesday, December 15, 2004

### More about the light cruiser design

## Tuesday, December 14, 2004

### My second Italian-looking light cruiser

## Monday, December 13, 2004

### I can report my light cruiser could reach 39 knots

### My attempt at a Bartolomeo Colleoni-style light cruiser

## Sunday, December 12, 2004

### My friend's GB/DL/1905 design

## Saturday, December 11, 2004

### Narrower beam producing a better ship seems counterintuitive to me

### The problem seems to be "excessive beam"

### My Ger/BB/1907 design

## Thursday, December 09, 2004

### There is not as much weight information for WWI destroyers as I would like to see

## Wednesday, December 08, 2004

### An 870 ton 1905 destroyer

## Tuesday, December 07, 2004

### Nathan Okun on the Bismarck, compared to contemporaries

## Monday, December 06, 2004

### D. K. Brown's book A Century of Naval Construction

## Sunday, December 05, 2004

### You couldn't build a balanced cruiser within the 10,000 ton limit

## Saturday, December 04, 2004

### The North Carolina Class Battleships

### The Japanese heavy cruiser Takao

## Friday, December 03, 2004

### American triple turrets with guns all in the same sleave

## Thursday, December 02, 2004

### DL-1 Norfolk: another Atlanta class variant

## Wednesday, December 01, 2004

### The fast AA cruiser devolved to the Mitscher class DL design

### US Navy thinking about speed in cruisers

## Tuesday, November 30, 2004

### I would be willing to run ship designs through my program

## Sunday, November 28, 2004

### Danger Spaces and Immune Zones

## Saturday, November 27, 2004

### B/H as a factor in propulsion

## Friday, November 26, 2004

### More about the Trento

### The Italian Trento class works like it should

### I find myself very gullible with respect to ship speeds

## Wednesday, November 24, 2004

### Some in the British navy were ready to adopt superfiring guns in 1905

### Retrograde influences on British warship design from 1903 to 1927

## Monday, November 22, 2004

### Tony DeGiulian at NavWeaps had some suggestions for sources

*Naval Weapons of World War II*. I never had any interest in this book until I found that I needed weights for fire control directors so that I could better calculate metacentric heights for WWII ships. I may need to consider that for WWI ships, as well, but hadn't seemed to need that information.

## Sunday, November 21, 2004

### Fire Control Directors

### Cruiser guns

## Saturday, November 20, 2004

### The Atlanta class cruisers (CL-51)

### Motor ships

## Friday, November 19, 2004

### Battleship-Cruisers

*Hood*almost was. The late 1930's fast battleships were exactly what William Hovgaard envisioned.

## Wednesday, November 17, 2004

### The reality is that ship sizes were limited by a number of factors

*North Carolina*class. Their problems were partially corrected in the

*South Dakota*class. At least, the

*South Dakota's*were structually sounder and better protected.

## Tuesday, November 16, 2004

### The DreadnoughtProject.org website

### A Question: how much should ship characteristics be constrained by date?

## Monday, November 15, 2004

### Japanese Cruisers: SHP/ton of machinery weight

- Tenryu 59,844 SHP 1042.9 tons 57.38 SHP/ton 1919
- Kuma 91,229 SHP 1588.1 tons 57.445 SHP/ton 1920
- Nagara 92,670 SHP 1630.3 tons 56.84 SHP/ton 1922
- Yubari 61,336 SHP 1056.5 tons 58.056 SHP/ton 1923
- Aoba 103,003 SHP 2173.7 tons 47.386 SHP/ton 1927
- Haguro 132,568 SHP 2689.5 tons 49.29 SHP/ton 1929
- Mogami 154,266 SHP 2477.3 tons 62.27 SHP/ton 1935
- Kumano 153,698 SHP 2358.1 tons 65.18 SHP/ton 1937

## Sunday, November 14, 2004

### Now, let's design the cruiser analog to the "moderate dimensions" battleship

### The "Moderate Dimensions" trap

Lord Brassey, and many others got caught up by the "Moderate Dimensions" trap. The argument stems from the knowledge that in sailing naval warfare, you didn't build a fleet of 100 gun ships, you built a fleet with a few 100 gun ships and many 74 gun and 64 gun ships. Logically, they thought the same idea should hold true in navies of ships built of steel and powered by steam. The counter argument is that you will end up with small ships, simply by the passage of time, as your latest ships will dwarf those built 5 years earlier. The biggest ships are the best armed and best protected, and nothing else can stand up to them. So don't build small, more lightly armed ships, as they are a waste, and will be defeated.

I've fallen into the moderate dimensions trap, myself, in that I'm interested in a smaller battleship, built to 1921 standards, with 9-15in/45 guns and 16-5.5in/50 guns. The speed would be 24 or 25 knots with a 32,500 ton displacement. The ship would be suitable for convoy escort and operations in secondary theaters. They could still put up a credible fight against stronger ships, although they would be unable to fight the really big ships with 18in or larger guns.

## Saturday, November 13, 2004

### The obvious thing to do now would be to try and make a Capitani Romani-style ship

### I'm working on a small cruiser design

## Friday, November 12, 2004

### The 5.1in/50 gun

Maximum penetration: 13.33 inches Elevation Range Belt Deck 1.9 deg 4100 yards 8 in 3.6 deg 6400 yards 6 in 7.1 deg 9800 yards 4 in 12.8 deg 13300 yards ... 1 in 18.6 deg 15600 yards 2 in 27.1 deg 17900 yards ... 2 in 47.7 deg 19300 yards ... 3 in Maximum range = 19500 yards at 42.5 deg elevation

### The 7.5in/50 gun performance

There is a striking difference between the 7.5in/50 gun firing a light projectile at high velocity and a heavy projectile at a lower velocity. This is what the performance looks like for the 200 lbs AP Shot at 2948 ft/sec:

Elevation Range Belt Deck 1.3 deg 3500 yards 14 in 2.1 deg 5100 yards 12 in 3.2 deg 7100 yards 10 in 4.9 deg 9400 yards 8 in 6.6 deg 11300 yards ... 1 in 8.0 deg 12600 yards 6 in 14.5 deg 17200 yards 4 in 16.7 deg 18400 yards ... 2 in 25.9 deg 22100 yards ... 3 in 35.4 deg 24400 yards 2 in 36.6 deg 24600 yards ... 4 in Maximum range = 25200 yards at 44.5 deg elevation

This is the gun with a velocity of 2691 ft/sec and a shot weight of 240 lbs:

Elevation Range Belt Deck 1.1 deg 2500 yards 16 in 1.9 deg 4200 yards 14 in 3.0 deg 6200 yards 12 in 4.7 deg 8500 yards 10 in 6.0 deg 10100 yards ... 1 in 7.2 deg 11400 yards 8 in 11.6 deg 15200 yards 6 in 15.0 deg 17400 yards ... 2 in 21.2 deg 20700 yards 4 in 22.4 deg 21200 yards ... 3 in 30.7 deg 24000 yards ... 4 in 40.1 deg 25700 yards ... 5 in 48.1 deg 25800 yards 2 in Maximum range = 26000 yards at 44.7 deg elevationI find it pretty amazing how more potent the gun is with the heavier shot.

### The 7.5in/50 gun

## Thursday, November 11, 2004

### A moderate-sized heavy cruiser design with 9-7.5in/50 guns

*Exeter*-type heavy cruiser (moderate dimensions) with 9-7.5in/50 guns. That gives a heavier broadside than 6-8in/50 guns and probably is superior from a gunnery perspective. I know that the British didn't like the 9-gun layout, but the ship would be able to fire alternate 4 and 5 gun salvos. That should be superior to 3-gun salvos from an

*Exeter*. The normal displacement is 9,070 tons with dimensions of 590ft x 60ft x 16.7ft. The designed speed at the normal displacement is 32 knots and not quite 31 knots at deep load. The maximum range, at 15 knots, is 10,090 nm. The belt is 3in and 16ft wide and the decks are 1.5in + 1in. The range at the normal load is only 4,030 nm at 15 knots. The normal fuel carried is 685 tons and the additional fuel carried at deep load is another 1,030 tons. I've designated the design as the GB/CA/1921d.

## Wednesday, November 10, 2004

### Details about the GB/CL/1921d type

### A light cruiser for trade protection (1921-style)

## Tuesday, November 09, 2004

### The GB/CA/1921c1 armored cruiser design

### My revised 9.2in gunned armored cruiser

## Monday, November 08, 2004

### This is too big a ship for the armament

### A triple 9.2in/50 turret

### A 1921 "armored cruiser"

## Sunday, November 07, 2004

### The slower heavy cruiser design

## Saturday, November 06, 2004

### A fast, 1921-style heavy cruiser

## Friday, November 05, 2004

### Tweaking the GB/CL/1921 Design

## Thursday, November 04, 2004

### My rationale for high-speed ships is for strategic mobility

## Wednesday, November 03, 2004

### Warship Speed in the early 20th Century

I have mixed feelings about the utility of speed in warships during the period from 1903 to 1945. For one thing, the period is not uniform. From the 1920's on, airpower had become a major factor. Prior to 1914, airpower was essentially a non-factor in operations.

During that time, the tactical value of speed was clear. The more speed, the greater the tactical advantage. After 1918, not all navies agreed on the importance of speed. In Britain, they were about ready to only build fast battleships (called battlecruisers, but heavily armored and gunned). In the U.S., the authorities dismissed the value of speed and were ready to build 32 knot cruisers rather than emulate the Japanese. The Japanese retained their mania for speed. The *Nagara* class were intended to be 36-knot ships. The original intent for the "10,000 ton cruisers" was for them to be 35-knot ships. They retained that desire right up until 1941. Having fast cruisers gave them ideal companions for fast aircraft carriers.

## Monday, November 01, 2004

### Specs for my 1921 super destroyer

Continuing my obsession with radical ship designs is my GB/DL/1921 super destroyer. The idea is that construction would have commenced in 1921.

- Year: 1921
- Length: 376.0 ft
- beam: 40.0 ft
- Hull depth: 26.0 ft
- Design displacement: 2840.0 tons
- Cp: 0.66
- Cm: 0.82
- Machinery Wt. Basis: 66.0 SHP/ton
- Hull Wt. Basis: 3.00 x 10^-3
- FreeboardForward: 25.0 ft
- FreeboardAmid: 13.0 ft
- FreeboardAft: 15.0 ft
- Designed SHP: 75000.0
- Designed Speed: 36.0 knots
- Board Margin: 50.0 tons
- Electrical Power KW: 300.0
- Main Batt Gun Type: 4.7in/50
- Main Batt guns: 5.0
- Main Batt Mount Type: shield
- Normal Fuel: 200 tons
- Extra Fuel for Deep Load: 250 tons

## Saturday, October 30, 2004

### This is the drawing of my "fast escort" (GB/DD/1921)

### This is my GB/CL/1921b light cruiser design

### Drawing of the GB/CL/1921a design

### A fast escort

### A 36-knot light cruiser

## Friday, October 29, 2004

### My 1921-style light cruiser

## Thursday, October 28, 2004

### Picture of the "Super-Fast Battlecruiser Alternative 2"

### More about the "Alternative Super Fast Battlecruiser" design

### I'm working on an "alternative" 1921-style "Super Fast Battlecruiser"

My modified design is flush decked with a transom stern. The bow is flared and rises to about 36ft above the waterline. To accommodate very highpower machinery, I have had to lengthen the citadel. That pushes the forward 17in/45 twin turret at least 50ft further forward. The bridge structure is reminiscent of what Edward Attwood and Stanley Goodall were using on the "1921" ships that were being designed prior to the Washington Naval Treaty. The machinery follows the "unit system", and pushing the forward turret further towards the bow gives more of a cruiser look than the design previously had.

## Wednesday, October 27, 2004

### Volume analysis is difficult, due to lack of data

### I'm surprised (but maybe shouldn't be) that the shorter ship could be faster

*Glorious*and

*Courageous*and the German design studies from 1917 and 1918. The

*GK 3022*was designed for 34 knots and had four large guns in two turrets.

## Tuesday, October 26, 2004

### Six shafts on a narrow ship

### Hitting the wall...

### The "so-called" 29,000 ton battlecruiser has the usual issue

### The 29,000 ton battleship design

Thanks to Blogger, I just lost what I had written about testing my Warship General Design computer program. The 29,000 ton battleship design seemed like a good test case for the program. There was the drawback that I did not have as much information that I would have liked from 30 years ago. I just had the basics, and would have to augment that in the ship specification. This is the basic specifications as originally conceived:

- 29,000 tons displacement at normal load
- dimensions: 620ft x 95ft x 30.2ft
- Cp=0.59
- Cm=0.97
- Armament: 6-13.5in/45 and 10-6in/50
- Machinery: 40,000 SHP

I found out quickly that I needed to decrease the Cp. I decided to go with 0.54, although lower would have given a higher speed. That alone raised the maximum speed to over 23 knots. I also found out that I needed to raise weights to decrease the metacentric height (GM). The ship is basically short and wide, so that inherently implies a high GM. I decreased the lower belt to 13in and increased the upper deck to 5in. I also included "upper deck side" armor. That lowered the GM at normal load to 4.92ft and at deep load to 6.77ft. The latter is still almost too large, but that is what seems reasonable.

## Monday, October 25, 2004

### Machinery volume and SHP/ton

### I'm doing all this empirical work to calculate volumes

## Sunday, October 24, 2004

### The next step is to add "volume" analysis

## Saturday, October 23, 2004

### New features to my Warship General Design program

### I want to add range calculations for specified cruising speed

### There is a different optimal Cp at legend and deep load displacements

### I've tryed opimizing and found that the smaller the Cm as possible, the better

### Winston Churchill on Destroyers

## Friday, October 22, 2004

### The "Super Fast Battlecruiser": experiments

- main battery turrets: 11in basis (greatest thickness)
- main battery barbettes: 9in basis
- lower belt: 9in
- upper belt: 6in
- deck forward: 2in
- deck aft: 3in
- a/t bulkhead: 1.5in
- shields on 4in guns: 1in

Metacentric height at legend displacement (GM)=5.25 ft

### I have looked at Greg Locock's DreadCAD Excel spreadsheet

## Thursday, October 21, 2004

### I've been doing some experiments with Cp and Cm

I have been tweaking the specs for my Ger/CS/1905 scout cruiser and the "Super-fast" battlecruiser to maximum speed. For the battlecruiser, there is the 70,000SHP/shaft limitation that has an effect. I thought it odd, but the lowest Cp doesn't give the highest speed. This is close to the best that can be done:

At Displacement=30949.2 tons Length=804.0 ft Beam=87.0 ft Draft=28.2078 ft Cp=0.61 Cm=0.9 Cb=0.549 DLR=59.5498 Wetted Surface=79812.8 sq. ft. B/H=3.08425 At speed of 35knots power is 223938.0 SHP At speed of 36knots power is 258375.0 SHP At speed of 37knots power is 301770.0 SHP actual speed for 280000.0 SHP is 36.4983 knots

I've wondered if optimizing Cp and Cm would be a worthwhile exercise. I would iterate over two ranges, looking for the highest speed for the maximum SHP.

### The modified "Super-fast" battlecruiser design (circa 1920)

ook the basic design for the really fast battlecruiser and modified them to try and get the Spring Style program to "work". I've used a variant of those specs to see what my program would produce with them:

- year: 1920
- length: 804.0 ft
- beam: 87.0 ft
- depth: 55.5 ft
- displacement: 34,312.0 tons
- cp: 0.60
- cm: 0.97
- machineryWtBasis: 28.6 SHP/ton of machinery
- hullWtBasis: 3.0x10^-3
- freeboardForward: 35.0 ft
- freeboardAmid: 26.0 ft
- freeboardAft: 26.0 ft
- forecastleLength: 270.0 ft
- designedShp: 275,000.0
- designedSpeed: 35.0
- boardMargin: 100.0 tons
- electricalPowerKW: 800.0KW
- mainBattType: 17in/45
- mainBattNum: 4.0
- mainBattMount: turret
- mainBattNumMounts: 2.0
- secBattType: 4in/50
- secBattNum: 16.0
- secBattMount: shield
- secBattNumMounts: 6.0
- forecastleDeck: 0.0 in
- upperDeck: 2.0 in
- lowerDeckSlopes:0.0 in
- lowerDeckFlat:0.0 in
- mainBattBarbette: 9.0 in
- mainBattTurret: 11.0 in
- upperDeckSide: 0.0 in
- upperBelt: 6.0 in
- lowerBelt: 6.0 in
- beltLength: 430.0 ft
- beltForward: 0.0 in
- beltAft: 0.0 in
- deckForward: 0.0 in
- deckAft: 3.0 in
- antiTorpBh: 1.5 in
- secBattArmor: 1.0 in
- uptakeArmor: 1.5 in

This is part of the result from my program:

Designed draft=29.4996 ft Hull Weight=11646.3 tons Secondary Battery Weight=80.96 Armament Weight= 2474.16 Total Armor Weight=4199.17 Machinery Weight=9615.38 General Equipment Weight=1029.36 Normal Fuel Weight=1029.36 Maximum Fuel added Weight=2573.4 Reserve Feedwater Weight=2004.75 Legend Displacement=31230.0 Legend Draft=26.8499 Submergence of 1390.61 of actual displacement per foot At Displacement=31230.0 Length=804.0 Beam=87.0 Draft=26.8499 Cp=0.6 Cm=0.97 Cb=0.582 DLR=60.0903 Wetted Surface=80174.1 B/H=3.24024 At speed of 35 knots power is 225983.0 SHP At speed of 36 knots power is 260739.0 SHP At speed of 37 knots power is 303780.0 SHP actual speed for 275000.0 SHP is 36.3313 knots Deep Load Displacement=35808.2 Deep Load Draft=30.1823 Submergence of 1409.25 of actual displacement per foot At speed of 34 knots power is 232583.0 SHP At speed of 35 knots power is 261412.0 SHP At speed of 36 knots power is 305432.0 SHP actual speed for 275000.0 SHP is 35.3087 knots Metacentric height at legend displacement (GM)=4.73343 ft Metacentric height at deep load displacement (GM)=6.97987 ft

## Wednesday, October 20, 2004

### British weight groups

## Monday, October 18, 2004

### My latest attempt at specifying the "super fast battlecruiser"

At Displacement=28708.8 Length=800.0 ft Beam=85.0 ft Draft=25.3893 ft Cp=0.6 Cm=0.97 Cb=0.582 Total Armor Weight=4166.51 tons Designed SHP=410000.0 Mach Wt Basis=40.0 SHP/Ton of machinery Machinery Weight=10250.0 tons General Equipment Weight=960.0 tons Normal Fuel Weight=960.0 tons Maximum Fuel added Weight=2400.0 tons Reserve Feedwater Weight=2988.9 tons Legend Displacement=28708.8 tons Legend Draft=25.3893 ft Submergence of 1351.88 of actual displacement per foot At Displacement=28708.8 tons DLR=56.0719 Wetted Surface=76678.3 B/H=3.34786 At speed of 10knots power is 2873.4 SHP At speed of 11knots power is 3774.54 SHP At speed of 12knots power is 4835.44 SHP At speed of 13knots power is 6072.19 SHP At speed of 14knots power is 7502.44 SHP At speed of 15knots power is 9324.9 SHP At speed of 16knots power is 11431.4 SHP At speed of 17knots power is 13784.6 SHP At speed of 18knots power is 16407.0 SHP At speed of 19knots power is 19312.1 SHP At speed of 20knots power is 22514.5 SHP At speed of 21knots power is 26004.9 SHP At speed of 22knots power is 31165.9 SHP At speed of 23knots power is 37151.1 SHP At speed of 24knots power is 43607.0 SHP At speed of 25knots power is 50598.1 SHP At speed of 26knots power is 58102.8 SHP At speed of 27knots power is 66131.4 SHP At speed of 28knots power is 74693.9 SHP At speed of 29knots power is 88418.3 SHP At speed of 30knots power is 104903.0 SHP At speed of 31knots power is 123016.0 SHP At speed of 32knots power is 142806.0 SHP At speed of 33knots power is 163796.0 SHP At speed of 34knots power is 185916.0 SHP At speed of 35knots power is 209122.0 SHP At speed of 36knots power is 240865.0 SHP At speed of 37knots power is 278425.0 SHP At speed of 38knots power is 318175.0 SHP At speed of 39knots power is 362385.0 SHP At speed of 40knots power is 408577.0 SHP At speed of 41knots power is 456762.0 SHP actual speed for 410000.0 SHP is 40.0295 knots Metacentric height at legend displacement (GM)= 3.30897 ft

### My 17in/45 gun design

I ran my 17in/45 gun design through Rick Robinson's gun calculation program with the following results. This is the sort of gun that would have been built after 1920, if there had not been a Washington Naval Treaty:

Caliber = 17.0 inch (43.2 cm) Shell weight = 2555 lbs (1159 kg) Muzzle velocity = 2650 fps (808 m/s) Relative ballistic performance: 0.80 Muzzle energy = 378.3 megajoules = 139421.9 foot-tons Relative muzzle energy: 0.89 Typical barrel length: 46 calibers Elevation Range Time Velocity Fall Angle 2.5 deg 5700 yards 7.0 sec 2254 fps 2.8 deg 5.0 deg 10300 yards 13.7 sec 1980 fps 6.1 deg 7.5 deg 14200 yards 20.0 sec 1790 fps 9.8 deg 10.0 deg 17600 yards 26.0 sec 1656 fps 13.7 deg 12.5 deg 20500 yards 31.8 sec 1560 fps 17.7 deg 15.0 deg 23100 yards 37.4 sec 1493 fps 21.7 deg 20.0 deg 27600 yards 48.1 sec 1421 fps 29.5 deg 25.0 deg 31300 yards 58.2 sec 1404 fps 36.5 deg 30.0 deg 34300 yards 67.9 sec 1418 fps 42.8 deg 35.0 deg 36600 yards 77.1 sec 1451 fps 48.1 deg 40.0 deg 38100 yards 85.8 sec 1493 fps 52.6 deg 45.0 deg 38800 yards 94.1 sec 1539 fps 56.8 deg 50.0 deg 38600 yards 101.8 sec 1584 fps 60.5 deg Armor Penetration - Vertical Belt Armor (Relative armor quality, 0.83) Maximum penetration: 41.00 inches Elevation Range Belt Deck 1.4 deg 3400 yards 36 in 2.1 deg 4900 yards 34 in 2.7 deg 6100 yards ... 1 in 2.9 deg 6400 yards 32 in 3.8 deg 8200 yards 30 in 4.8 deg 10000 yards 28 in 5.0 deg 10400 yards ... 2 in 6.0 deg 11900 yards 26 in 7.4 deg 14100 yards 24 in 7.4 deg 14100 yards ... 3 in 9.1 deg 16400 yards 22 in 10.1 deg 17700 yards ... 4 in 11.2 deg 19000 yards 20 in 13.6 deg 21600 yards ... 5 in 13.9 deg 22000 yards 18 in 17.4 deg 25400 yards 16 in 17.5 deg 25500 yards ... 6 in 20.2 deg 27700 yards ... 7 in 22.3 deg 29400 yards 14 in 22.8 deg 29800 yards ... 8 in 25.6 deg 31600 yards ... 9 in 28.3 deg 33300 yards ... 10 in 29.2 deg 33800 yards 12 in 31.1 deg 34800 yards ... 11 in 34.0 deg 36100 yards ... 12 in 37.0 deg 37300 yards ... 13 in 39.0 deg 37900 yards 10 in 39.9 deg 38100 yards ... 14 in 43.0 deg 38700 yards ... 15 in 46.2 deg 38900 yards ... 16 in 49.5 deg 38700 yards ... 17 in Maximum range = 38900 yards at 46.4 deg elevation

### Weight groups

Yesterday, I ran into the issue of weight groups and how they are defined. I have data for an American battleship design and started to enter that into my program. I quickly found that I couldn't make the design work as specified, and then realized that to make it work, I would need to transform the data into the British weight groups, not the American. In Chapter III of *General Design of Warships*, William Hovgaard has a comparison of the British, American, and French weight groups. My program is hard-wired to use the British weight group scheme, and could not easily be modified to use the American (at least not without many code changes).

## Sunday, October 17, 2004

### Specs for a version of "The Ideal Battleship for the British Navy"

The following is what I used for the version of Colonel Cuniberti's "Ideal Battleship for the British Navy". I had to reduce the armor to be able to keep the size under 18,000 tons with the specified length and beam:

### The first run from my program for Colonel Cuniberti's battleship

I found that if I severely cut back the armor protection, I could get a reasonable result for Colonel Cuniberti's "Ideal Battleship for the British Navy" from 1903. Instead of a 12in armor basis, I found that a 9in basis was more workable. I also had to give pretty powerful machinery to achieve the desired speed, and to use a lighter-weight machinery to do it:

Designed draft=27.8055 ft Hull Weight=6511.95 tons Tertiary Battery Weight=3.8916 Armament Weight= 3013.89 Total Armor Weight=3261.92 Machinery Weight=3375.0 General Equipment Weight=510.0 Normal Fuel Weight=510.0 Maximum Fuel added Weight=1275.0 Reserve Feedwater Weight=393.66 Legend Displacement=17630.8 Legend Draft=28.8372 Submergence of 768.321 of actual displacement per foot At Displacement=17630.8 Length=521.5 ft Beam=82.0 ft Draft=28.8372 ft Cp=0.556 Cm=0.9 Cb=0.5004 DLR=124.311 Wetted Surface=48515.7 B/H=2.84355 At speed of 10knots power is 1983.53 SHP At speed of 11knots power is 2596.19 SHP At speed of 12knots power is 3404.1 SHP At speed of 13knots power is 4408.89 SHP At speed of 14knots power is 5567.12 SHP At speed of 15knots power is 6881.56 SHP At speed of 16knots power is 8365.81 SHP At speed of 17knots power is 10018.2 SHP At speed of 18knots power is 12518.6 SHP At speed of 19knots power is 15375.7 SHP At speed of 20knots power is 18522.1 SHP At speed of 21knots power is 21955.0 SHP At speed of 22knots power is 25689.7 SHP At speed of 23knots power is 31378.4 SHP At speed of 24knots power is 46152.3 SHP At speed of 25knots power is 61598.7 SHP actual speed for 54000.0 SHP is 24.5081 Deep Load Displacement=19299.4 Deep Load Draft=30.9476 Submergence of 778.621 of actual displacement per foot At Displacement=19299.4 Length=521.5 Beam=82.0 Draft=30.9453 Cp=0.56434 Cm=0.9045 Cb=0.510445 DLR=136.076 Wetted Surface=50759.7 B/H=2.64984 At speed of 10knots power is 2093.98 SHP At speed of 11knots power is 2740.18 SHP At speed of 12knots power is 3593.29 SHP At speed of 13knots power is 4654.88 SHP At speed of 14knots power is 5878.19 SHP At speed of 15knots power is 7266.12 SHP At speed of 16knots power is 8832.88 SHP At speed of 17knots power is 10576.8 SHP At speed of 18knots power is 13371.3 SHP At speed of 19knots power is 16583.1 SHP At speed of 20knots power is 20119.5 SHP At speed of 21knots power is 23977.4 SHP At speed of 22knots power is 28173.0 SHP At speed of 23knots power is 34664.5 SHP At speed of 24knots power is 51432.0 SHP At speed of 25knots power is 68328.5 SHP actual speed for 54000.0 SHP is 24.152 At Legend Displacement: Waterline Coeff=0.671089 Block Coefficient=0.5004 CG of hull=21.7742 Hull Wt=6511.95 CG of machinery=11.3933 Mach Wt=3375.0 Armor Center of gravity=43.6179 CG of armor=43.6179 Armor Wt=5324.78 CG of normal fuel=12.1954 Normal Fuel Wt=765.0 CG of max fuel= n/a Additional Max Fuel Wt=0.0 CG of upper works=69.12 Upper Works Wt=71.3698 CG of general equipment=28.08 General Equip Wt=510.0 Main Armament CG=50.0 Main armament wt=3013.89 Secondary Batt CG=0.0 Secondary Batt wt: 0.0 Tertiary Batt CG=0.0 Tertiary Batt wt: 3.8916 CG above keel = 30.23 Stability Coeff (nu)=0.559814 Height of CG as a fraction of the depth=0.559814 Freeboard=25.1628 ft Draft=28.8372 ft Beam=82.0 ft Metacentric height at legend displacement (GM)=5.20457 ft At Deep Load Displacement: Waterline Coeff=0.671089 Block Coefficient=0.5004 CG of hull=21.7742 Hull Wt=6511.95 CG of machinery=11.3933 Mach Wt=3375.0 Armor Center of gravity=44.4982 CG of armor=44.4982 Armor Wt=5324.78 CG of normal fuel=12.6479 Normal Fuel Wt=765.0 CG of max fuel=12.6479 Additional Max Fuel Wt=1275.0 CG of upper works=69.12 Upper Works Wt=71.3698 CG of general equipment=28.08 General Equip Wt=510.0 Main Armament CG=50.0 Main armament wt=3013.89 Secondary Batt CG=0.0 Secondary Batt wt: 0.0 Tertiary Batt CG=0.0 Tertiary Batt wt: 3.8916 CG above keel = 28.6229 Stability Coeff (nu)=0.530053 Height of CG as a fraction of the depth=0.530053 Freeboard=23.0524 Draft=30.9476 Beam=82.0 Metacentric height at deep load displacement (GM)=6.77938 ft

### I want to revisit Colonel Cuniberti's 1903 battleship design

I will be reanalyzing Colonel Cunibert's 1903 all-big gun battleship design with my program in its current form. I expect that I will find, as before, that he was extravagantly over-optimistic about how small the ship could be (17,000 tons). What he described was clearly a battleship-cruiser, similar to William Hovgaard's original conception.

## Saturday, October 16, 2004

### Now, the Ger/CB/1906 with the latest version of my program

Trying out the Ger/CB/1906 design is not as traumatic, as it naturally has a higher center of gravity and lower GM (although still really high). This is another low-silhouette, fast battlecruiser design. The main difference is that the main armament is 8-12in/45 guns with a secondary armament of 12-4in/50 guns. The side armor is still only 4in and the upper deck is 3in. The main battery turrets and barbettes are 6in. Here is what the output from my program is like for this design:

Designed draft=25.5564 ft Hull Weight=11016.0 tons Secondary Battery Weight=60.72 tons Armament Weight= 2155.72 tons Total Armor Weight=2675.07 tons Machinery Weight=8428.57 tons General Equipment Weight=750.0 tons Normal Fuel Weight=750.0 tons Maximum Fuel added Weight=1875.0 tons Reserve Feedwater Weight=1075.28 tons Legend Displacement=26570.4 tons Legend Draft=27.1617 Submergence of 1226.82 of actual displacement per foot At Displacement=26570.4 Length=800.0 ft Beam=85.0 ft Draft=27.1617 ft Cp=0.53 Cm=0.95 Cb=0.5035 At Displacement=26570.4 tons DLR=51.8952 Wetted Surface=73767.3 B/H=3.12941 At speed of 10knots power is 2705.44 SHP At speed of 11knots power is 3546.97 SHP At speed of 12knots power is 4538.67 SHP At speed of 13knots power is 5695.98 SHP At speed of 14knots power is 7035.9 SHP At speed of 15knots power is 8695.54 SHP At speed of 16knots power is 10608.1 SHP At speed of 17knots power is 12746.2 SHP At speed of 18knots power is 15131.1 SHP At speed of 19knots power is 17776.2 SHP At speed of 20knots power is 20695.3 SHP At speed of 21knots power is 23879.4 SHP At speed of 22knots power is 27982.3 SHP At speed of 23knots power is 32612.8 SHP At speed of 24knots power is 37606.0 SHP At speed of 25knots power is 43023.9 SHP At speed of 26knots power is 48845.8 SHP At speed of 27knots power is 55081.6 SHP At speed of 28knots power is 61741.0 SHP At speed of 29knots power is 75542.8 SHP At speed of 30knots power is 92998.3 SHP At speed of 31knots power is 111556.0 SHP At speed of 32knots power is 131184.0 SHP At speed of 33knots power is 152017.0 SHP actual speed for 147500.0 SHP is 32.7832 knots Deep Load Displacement=29520.6 tons Deep Load Draft=29.5859 Submergence of 1243.27 of actual displacement per foot Metacentric height at legend displacement (GM)=8.84576 ft Metacentric height at deep load displacement (GM)=10.0769 ft

### I'm doing some outrageous things to try and lower the GM

After calibrating my program for the Queen Elizabeth class, I am now wrestling with the ship specification for my GB/CB/1905 design to try and lower the metacentric height (GM). I have had only moderate success at this, but I do have the GM at the legend displacement below 10ft (!). I must admit that the ship has a low silhouette, given that it doesn't have superfiring turrets. There are just the forward and aft 12in/45 twin turrets with 9 single 6in/50 guns in armored shields. As things stand right now, this is what I have:

Designed draft=26.0604 ft Hull Weight=10995.6 tons Secondary Battery Weight=165.6 tons (includes protection) Armament Weight= 1576.08 tons (includes protection) Total Armor Weight=4097.17 tons Machinery Weight=8428.57 tons General Equipment Weight=750.0 tons Normal Fuel Weight=750.0 tons Maximum Fuel added Weight=1875.0 tons Reserve Feedwater Weight=1075.28 tons Legend Displacement=27392.4 tons Legend Draft=28.5543 ft Submergence of 1195.69 of actual displacement per foot At Displacement=27392.4 Length=770.0 ft Beam=85.0 ft Draft=28.5543 ft Cp=0.54 Cm=0.95 Cb=0.513 At Displacement=27392.4 tons DLR=60.001 Wetted Surface=73481.9 B/H=2.97679 At speed of 30knots power is 104406.0 SHP At speed of 31knots power is 125104.0 SHP At speed of 32knots power is 147027.0 SHP At speed of 33knots power is 170186.0 SHP actual speed for 147500.0 SHP is 32.0204 Metacentric height at legend displacement (GM)=9.36508 Waterline Coeff=0.661362 Block Coefficient=0.513 Stability Coeff (nu)=0.445718 Freeboard=24.9905 Draft=31.0095 Beam=85.0 Metacentric height at deep load displacement (GM)=10.4897

### I'm still "wrestling" with the Queen Elizabeth class

Something about the Queen Elizabeth class battleships is challenging. It didn't work at all in Rick Robinson's "Spring Style" program (at least the way I specified it). In my program, I'm having trouble getting a large enough metacentric height (GM) at the legend displacement. The deep load is better, but still lower than the real ships. One good thing is that I have a more complete weight and stability model than I did, even earlier today. I have yet to deal with volumes and seakeeping ability, but that is coming soon. As it stands right now, I am getting the following results: