Esc Cruiser-killer

[ledeper]

Hammer, Esc Cruiser-killer laid down 1917 (Engine 1916)

Displacement:
   21.333 t light; 22.359 t standard; 24.315 t normal; 25.879 t full load

Dimensions: Length overall / water x beam x draught
   720,01 ft / 716,54 ft x 91,86 ft x 25,75 ft (normal load)
   219,46 m / 218,40 m x 28,00 m  x 7,85 m

Armament:
      6 - 13,78" / 350 mm guns (2x3 guns), 1.308,20lbs / 593,39kg shells, 1917 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread
      8 - 5,91" / 150 mm guns in single mounts, 102,98lbs / 46,71kg shells, 1917 Model
     Quick firing guns in deck mounts
     on side, all amidships
      10 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,89kg shells, 1917 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread
   Weight of broadside 8.693 lbs / 3.943 kg
   Shells per gun, main battery: 110

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   9,84" / 250 mm   465,75 ft / 141,96 m   13,48 ft / 4,11 m
   Ends:   Unarmoured
   Upper:   3,94" / 100 mm   465,75 ft / 141,96 m   8,01 ft / 2,44 m
     Main Belt covers 100 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   9,84" / 250 mm   3,94" / 100 mm      7,87" / 200 mm
   2nd:   0,98" / 25 mm         -               -

   - Armour deck: 2,95" / 75 mm, Conning tower: 9,84" / 250 mm

Machinery:
   Oil fired boilers, steam turbines plus diesel motors,
   Electric cruising motors plus geared drives, 4 shafts, 95.101 shp / 70.946 Kw = 29,00 kts
   Range 8.000nm at 14,00 kts
   Bunker at max displacement = 3.520 tons

Complement:
   973 - 1.265

Cost:
   £3,919 million / $15,676 million

Distribution of weights at normal displacement:
   Armament: 1.087 tons, 4,5 %
   Armour: 6.662 tons, 27,4 %
      - Belts: 3.255 tons, 13,4 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 829 tons, 3,4 %
      - Armour Deck: 2.400 tons, 9,9 %
      - Conning Tower: 178 tons, 0,7 %
   Machinery: 3.543 tons, 14,6 %
   Hull, fittings & equipment: 9.391 tons, 38,6 %
   Fuel, ammunition & stores: 2.982 tons, 12,3 %
   Miscellaneous weights: 650 tons, 2,7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     30.467 lbs / 13.820 Kg = 23,3 x 13,8 " / 350 mm shells or 3,1 torpedoes
   Stability (Unstable if below 1.00): 1,31
   Metacentric height 7,1 ft / 2,2 m
   Roll period: 14,5 seconds
   Steadiness   - As gun platform (Average = 50 %): 53 %
         - Recoil effect (Restricted arc if above 1.00): 0,30
   Seaboat quality  (Average = 1.00): 1,05

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,502
   Length to Beam Ratio: 7,80 : 1
   'Natural speed' for length: 26,77 kts
   Power going to wave formation at top speed: 49 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19,69 ft / 6,00 m
      - Forecastle (20 %):   16,40 ft / 5,00 m
      - Mid (50 %):      16,40 ft / 5,00 m
      - Quarterdeck (15 %):   16,40 ft / 5,00 m
      - Stern:      16,40 ft / 5,00 m
      - Average freeboard:   16,67 ft / 5,08 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 84,3 %
      - Above water (accommodation/working, high = better): 141,1 %
   Waterplane Area: 43.937 Square feet or 4.082 Square metres
   Displacement factor (Displacement / loading): 105 %
   Structure weight / hull surface area: 159 lbs/sq ft or 777 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1,00
      - Longitudinal: 1,02
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent

10 dg outward slope

[The Rock Doctor]

Not bad, not bad.  Nice firepower and speed for the size.

[miketr]

Very interesting design and the cruiser killer type is popular with people in navalism.  I would think 30+ knots would be in order though to assure you could run down CL's / PC's.

[maddox]

Not something Nverse France would build.

The guns are overkill for PC's and CL's, the speed too low to chase the new PC and CL's and the rest of the ship ain't ment to slug it out with BC's or BB's.

Nonetheless, she's a tough cookie, and not something to meet overconfident.

[ledeper]

Another option 12" guns instead of 14" 1½ knt faster:
Hammer, Esc Cruiser-killer laid down 1917 (Engine 1916)

Displacement:
   20.341 t light; 21.165 t standard; 23.055 t normal; 24.568 t full load

Dimensions: Length overall / water x beam x draught
   720,01 ft / 716,54 ft x 91,86 ft x 25,75 ft (normal load)
   219,46 m / 218,40 m x 28,00 m  x 7,85 m

Armament:
      6 - 11,81" / 300 mm guns (2x3 guns), 823,82lbs / 373,68kg shells, 1917 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread
      8 - 5,91" / 150 mm guns in single mounts, 102,98lbs / 46,71kg shells, 1917 Model
     Quick firing guns in deck mounts
     on side, all amidships
      10 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,89kg shells, 1917 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread
   Weight of broadside 5.786 lbs / 2.625 kg
   Shells per gun, main battery: 110

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   9,84" / 250 mm   446,19 ft / 136,00 m   13,48 ft / 4,11 m
   Ends:   Unarmoured
   Upper:   3,94" / 100 mm   465,75 ft / 141,96 m   8,01 ft / 2,44 m
     Main Belt covers 96 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   9,84" / 250 mm   3,94" / 100 mm      7,87" / 200 mm
   2nd:   0,98" / 25 mm         -               -

   - Armour deck: 2,95" / 75 mm, Conning tower: 9,84" / 250 mm

Machinery:
   Diesel Internal combustion motors,
   Electric cruising motors plus geared drives, 4 shafts, 110.845 shp / 82.690 Kw = 30,50 kts
   Range 8.000nm at 14,00 kts
   Bunker at max displacement = 3.402 tons

Complement:
   935 - 1.216

Cost:
   £3,450 million / $13,801 million

Distribution of weights at normal displacement:
   Armament: 723 tons, 3,1 %
   Armour: 6.373 tons, 27,6 %
      - Belts: 3.163 tons, 13,7 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 694 tons, 3,0 %
      - Armour Deck: 2.345 tons, 10,2 %
      - Conning Tower: 172 tons, 0,7 %
   Machinery: 4.130 tons, 17,9 %
   Hull, fittings & equipment: 8.465 tons, 36,7 %
   Fuel, ammunition & stores: 2.714 tons, 11,8 %
   Miscellaneous weights: 650 tons, 2,8 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     29.481 lbs / 13.372 Kg = 35,8 x 11,8 " / 300 mm shells or 3,0 torpedoes
   Stability (Unstable if below 1.00): 1,36
   Metacentric height 7,6 ft / 2,3 m
   Roll period: 14,0 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0,19
   Seaboat quality  (Average = 1.00): 1,01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,476
   Length to Beam Ratio: 7,80 : 1
   'Natural speed' for length: 26,77 kts
   Power going to wave formation at top speed: 51 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      19,69 ft / 6,00 m
      - Forecastle (20 %):   16,40 ft / 5,00 m
      - Mid (50 %):      16,40 ft / 5,00 m
      - Quarterdeck (15 %):   16,40 ft / 5,00 m
      - Stern:      16,40 ft / 5,00 m
      - Average freeboard:   16,67 ft / 5,08 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 85,3 %
      - Above water (accommodation/working, high = better): 143,4 %
   Waterplane Area: 42.925 Square feet or 3.988 Square metres
   Displacement factor (Displacement / loading): 109 %
   Structure weight / hull surface area: 146 lbs/sq ft or 715 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1,01
      - Longitudinal: 1,00
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is excellent

10 dg outward slope

[maddox]

That's a lot more interesting for the job .

Of course, that is what I think.

[miketr]

This is what I came up for a cruiser killer.

http://www.navalism.org/index.php?topic=3227.msg37526#msg37526

The first one is under construction right now.

[Guinness]

What's the 650t of misc weight for?

[miketr]

I would assume FC, radio and large construction reserve.

[ledeper]

2x firecontrol 500t,"radar" 25 t L/R WT 5o t

[Kaiser Kirk]

Why dispense with steam turbines on the second iteration?

Seems like a lot of 40mm AA for the time and the scarcity of seaborne aircraft.

Fairly expensive asset not to have a TDS system

I don't *get* BC, don't have a feel for what is reasonable... but over on Wesworld, Hooman would certainly grumble about a 20k vessel with a 0.476. What happens if you reduce beam and increase BC?

I would guess you're expecting longish stern chases with a fair number of long range shots. While even at 1% hitting, you'd land 4-5 before running out, which would kill a cruiser, but run your magazines low.  Especially if you have say 10 training , 20 HE, 20 SAP and 60 AP.

[Guinness]

We get grumbling around here from time to time about BC as well. .476 is certainly fine, but not completely out of whack with nverse precedent previously.

I did a L/B study of capital ships a while back. I might need to try to do the same thing for BC, but unfortunately that data is harder to find if you don't have the right sources. I can certainly get it for most or all of the US BB and CA classes from Friedman, but I'd be interested in other navies as well. Going from memory, most US treaty cruisers had BCs between .52 and .58 IIRC.

The biggest issue I see with BC that is too fine in such a ship is that you probably don't have enough space forward and aft for magazines, etc. This is admittedly a problem with the Confederate Enterprise class.

[Kaiser Kirk]

Thats one of the reasons I can't visualize it, don't run across BC numbers for vessels very often. Tried to synthesis it once by plugging in the basic parameters for various ships into SS to get an idea of the range, but I was looking for upper range of BBs.

[ledeper]

Reduced draft by 85 cm ,raised free board by 70 cm ,reduced speed with ½ knot and thus increased BC to 0,528:
Hammer, Esc Cruiser-killer laid down 1917 (Engine 1916)

Displacement:
   21.591 t light; 22.443 t standard; 24.434 t normal; 26.027 t full load

Dimensions: Length overall / water x beam x draught
   720,58 ft / 716,54 ft x 98,43 ft x 22,97 ft (normal load)
   219,63 m / 218,40 m x 30,00 m  x 7,00 m

Armament:
      6 - 11,81" / 300 mm guns (2x3 guns), 823,82lbs / 373,68kg shells, 1917 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread
      8 - 5,91" / 150 mm guns in single mounts, 102,98lbs / 46,71kg shells, 1917 Model
     Quick firing guns in deck mounts
     on side, all amidships
      10 - 1,57" / 40,0 mm guns in single mounts, 1,95lbs / 0,89kg shells, 1917 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread
   Weight of broadside 5.786 lbs / 2.625 kg
   Shells per gun, main battery: 110

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   9,84" / 250 mm   446,19 ft / 136,00 m   13,48 ft / 4,11 m
   Ends:   Unarmoured
   Upper:   3,94" / 100 mm   465,75 ft / 141,96 m   8,01 ft / 2,44 m
     Main Belt covers 96 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   9,84" / 250 mm   3,94" / 100 mm      7,87" / 200 mm
   2nd:   0,98" / 25 mm         -               -

   - Armour deck: 2,95" / 75 mm, Conning tower: 9,84" / 250 mm

Machinery:
   Oil fired boilers, steam turbines plus diesel motors,
   Electric cruising motors plus geared drives, 4 shafts, 112.222 shp / 83.717 Kw = 30,00 kts
   Range 8.000nm at 14,00 kts
   Bunker at max displacement = 3.584 tons

Complement:
   976 - 1.270

Cost:
   £3,543 million / $14,172 million

Distribution of weights at normal displacement:
   Armament: 723 tons, 3,0 %
   Armour: 6.754 tons, 27,6 %
      - Belts: 3.192 tons, 13,1 %
      - Torpedo bulkhead: 0 tons, 0,0 %
      - Armament: 749 tons, 3,1 %
      - Armour Deck: 2.634 tons, 10,8 %
      - Conning Tower: 179 tons, 0,7 %
   Machinery: 4.181 tons, 17,1 %
   Hull, fittings & equipment: 9.283 tons, 38,0 %
   Fuel, ammunition & stores: 2.843 tons, 11,6 %
   Miscellaneous weights: 650 tons, 2,7 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     36.730 lbs / 16.660 Kg = 44,6 x 11,8 " / 300 mm shells or 3,5 torpedoes
   Stability (Unstable if below 1.00): 1,41
   Metacentric height 8,9 ft / 2,7 m
   Roll period: 13,8 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0,17
   Seaboat quality  (Average = 1.00): 1,02

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0,528
   Length to Beam Ratio: 7,28 : 1
   'Natural speed' for length: 26,77 kts
   Power going to wave formation at top speed: 52 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = measuring location as a percentage of overall length):
      - Stem:      22,97 ft / 7,00 m
      - Forecastle (20 %):   18,73 ft / 5,71 m
      - Mid (50 %):      18,73 ft / 5,71 m
      - Quarterdeck (15 %):   18,73 ft / 5,71 m
      - Stern:      18,73 ft / 5,71 m
      - Average freeboard:   19,07 ft / 5,81 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 81,3 %
      - Above water (accommodation/working, high = better): 176,3 %
   Waterplane Area: 48.217 Square feet or 4.480 Square metres
   Displacement factor (Displacement / loading): 113 %
   Structure weight / hull surface area: 148 lbs/sq ft or 721 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1,00
      - Longitudinal: 1,02
      - Overall: 1,00
   Hull space for machinery, storage, compartmentation is excellent
   Room for accommodation and workspaces is excellent

10 dg outward slope

[Guinness]

I went through Friedman's books and compiled a mess of block coefficients for US ships, plus Bismarck and Yamato:

http://www.navalism.org/index.php?topic=727.msg44539#msg44539

If I have some time I may mine the internet a bit more for others.