Smaller Cruisers ??

[mentat]

  A while back - thinking that we have another 10 years or so before Aircraft can become the main Long Range Strike weapon - I posted thoughts on Large Fast Long Range Cruisers - in the Strike role

  Didn't seem to get much response - not sure if this was because many thought them an expensive and exorbitant luxury - or if everyone is keeping quiet and secretly building lots of 'Super Wheelers' for highly malevalent purposes ...  :o

Anyway - by way of contrast - thought I might switch tack - and explore:

    - "What is the Smallest Size of useful/Practical Heavy Cruiser?"

  Here goes - various options starting from Limited Capability - and going up ...

  First - Version A - on the slow and short range side of things - but still useful for - Defensive Purposes - defending more important Convoys, supporting lighter forces etc

Second - Version B - I think more practical Speed and Range for Fleet Operations

Third - Version C - back to more Aggressive posture - a decent Cruising Cruiser (it's what they're for) - capable of longer range Independent Operations ...



A - Short Range, Defensive Version:


Defender, BAE Heavy Cruiser laid down 1920

Displacement:
7,717 t light; 8,162 t standard; 8,744 t normal; 9,210 t full load

Dimensions: Length overall / water x beam x draught
553.88 ft / 550.00 ft x 60.00 ft x 17.75 ft (normal load)
168.82 m / 167.64 m x 18.29 m  x 5.41 m

Armament:
      6 - 8.66" / 220 mm guns (3x2 guns), 325.00lbs / 147.42kg shells, 1920 Mode
  Breech loading guns in turrets (on barbettes)
  on centreline ends, majority aft
      10 - 4.72" / 120 mm guns (5x2 guns), 55.00lbs / 24.95kg shells, 1920 Model
   Quick firing guns in deck mounts with hoists
  on side, all amidships, 1 raised mount - superfiring
      4 - 2.76" / 70.0 mm guns in single mounts, 10.50lbs / 4.76kg shells, 1920 Model
   Anti-aircraft guns in deck mounts
   on side, evenly spread, all raised mounts
      24 - 1.00" / 25.4 mm guns (12x2 guns), 0.50lbs / 0.23kg shells, 1920 Model
   Machine guns in deck mounts
   on side, evenly spread, all raised mounts
Weight of broadside 2,554 lbs / 1,158 kg
Shells per gun, main battery: 180
8 - 22.0" / 558.8 mm above water torpedoes

Armour:
   - Belts: Width (max)\tab Length (avg)\tab\tab Height (avg)
Main:\tab 4.00" / 102 mm\tab 360.00 ft / 109.73 m\tab 12.00 ft / 3.66 m
Ends:\tab 1.50" / 38 mm\tab 190.00 ft / 57.91 m\tab 8.00 ft / 2.44 m
Upper:\tab 2.00" / 51 mm\tab 200.00 ft / 60.96 m\tab 8.00 ft / 2.44 m
   Main Belt covers 101 % of normal length

   - Gun armour:\Face (max)\ Other gunhouse (avg)\tab Barbette/hoist (max
Main: 4.00" / 102 mm 2.00" / 51 mm 3.00" / 76 mm
2nd: 1.50" / 38 mm 1.20" / 30 mm 1.50" / 38 mm
3rd: 0.80" / 20 mm 0.60" / 15 mm   
4th: 0.60" / 15 mm

   - Armour deck: 1.20" / 30 mm, Conning tower: 5.00" / 127 mm

Machinery:
Oil fired boilers, steam turbines,
Geared drive, 4 shafts, 51,496 shp / 38,416 Kw = 28.50 kts
Range 7,000nm at 12.00 kts
Bunker at max displacement = 1,049 tons

Complement:
451 - 587

Cost:
GBP 1.862 million / $7.449 million

Distribution of weights at normal displacement:
Armament: 316 tons, 3.6 %
Armour: 1,776 tons, 20.3 %
    - Belts: 960 tons, 11.0 %
    - Torpedo bulkhead: 0 tons, 0.0 %
    - Armament: 272 tons, 3.1 %
    - Armour Deck: 498 tons, 5.7 %
    - Conning Tower: 46 tons, 0.5 %
Machinery: 1,801 tons, 20.6 %\
Hull, fittings & equipment: 3,575 tons, 40.9 %
Fuel, ammunition & stores: 1,027 tons, 11.7 %
Miscellaneous weights: 250 tons, 2.9 %\par

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
   10,233 lbs / 4,641 Kg = 31.5 x 8.7 " / 220 mm shells or 1.5 torpedoes
Stability (Unstable if below 1.00): 1.10
Metacentric height 2.8 ft / 0.8 m
Roll period: 15.1 seconds
Steadiness\tab - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.63
Seaboat quality  (Average = 1.00): 1.09

Hull form characteristics:
Hull has rise forward of midbreak
Block coefficient: 0.523
Length to Beam Ratio: 9.17 : 1
'Natural speed' for length: 23.45 kts
Power going to wave formation at top speed: 53 %
Trim (Max stability = 0, Max steadiness = 100): 64
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: 22.00 ft / 6.71 m\
    - Forecastle (20 %): 21.00 ft / 6.40 m
    - Mid (50 %): 20.00 ft / 6.10 m (13.00 ft / 3.96 m aft of break)
    - Quarterdeck (15 %): 13.00 ft / 3.96 m
    - Stern: 14.00 ft / 4.27 m
   - Average freeboard: 17.01 ft / 5.18 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 98.8 %
- Above water (accommodation/working, high = better): 127.4 %
Waterplane Area: 22,447 Square feet or 2,085 Square metres
Displacement factor (Displacement / loading): 107 %\par
Structure weight / hull surface area: 107 lbs/sq ft or 521 Kg/sq metre
Hull strength (Relative)
- Cross-sectional: 0.98
- Longitudinal: 1.19
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform


Version B - Fleet Capable:

Defender, BAE Heavy Cruiser laid down 1920

Displacement:
9,219 t light; 9,699 t standard; 10,532 t normal; 11,199 t full load

Dimensions: Length overall / water x beam x draught\par
589.41 ft / 585.00 ft x 67.00 ft x 18.00 ft (normal load)\par
179.65 m / 178.31 m x 20.42 m  x 5.49 m\par

Armament:\par
      6 - 8.66" / 220 mm guns (3x2 guns), 325.00lbs / 147.42kg shells, 1920 Model\par
   Breech loading guns in turrets (on barbettes)\par
   on centreline ends, majority aft\par
      10 - 4.72" / 120 mm guns (5x2 guns), 55.00lbs / 24.95kg shells, 1920 Model\par
   Quick firing guns in deck mounts with hoists\par
   on side, all amidships, 1 raised mount - superfiring\par
      4 - 2.76" / 70.0 mm guns in single mounts, 10.50lbs / 4.76kg shells, 1920 Model\par
   Anti-aircraft guns in deck mounts \par
   on side, evenly spread, all raised mounts\par
      24 - 1.00" / 25.4 mm guns (12x2 guns), 0.50lbs / 0.23kg shells, 1920 Model\par
   Machine guns in deck mounts \par
   on side, evenly spread, all raised mounts\par
Weight of broadside 2,554 lbs / 1,158 kg\par
Shells per gun, main battery: 180\par
8 - 22.0" / 558.8 mm above water torpedoes\par

Armour:\par
- Belts:\tab\tab Width (max)\tab Length (avg)\tab\tab Height (avg)\par
Main:\tab 4.00" / 102 mm\tab 400.00 ft / 121.92 m\tab 12.00 ft / 3.66 m\par
Ends:\tab 1.50" / 38 mm\tab 185.00 ft / 56.39 m\tab 8.00 ft / 2.44 m\par
Upper:\tab 2.00" / 51 mm\tab 240.00 ft / 73.15 m\tab 8.00 ft / 2.44 m\par
   Main Belt covers 105 % of normal length\par

   - Gun armour:\tab Face (max)\tab Other gunhouse (avg)\tab Barbette/hoist (max)\par
Main:\tab 4.00" / 102 mm\tab 2.00" / 51 mm\tab\tab 3.00" / 76 mm\par
2nd:\tab 1.50" / 38 mm\tab 1.20" / 30 mm\tab\tab 1.50" / 38 mm\par
3rd:\tab 0.80" / 20 mm\tab 0.60" / 15 mm\tab\tab       -\par
4th:\tab 0.60" / 15 mm\tab       -\tab\tab\tab       -\par

   - Armour deck: 1.20" / 30 mm, Conning tower: 5.00" / 127 mm\par

Machinery:\par
Oil fired boilers, steam turbines, \par
Geared drive, 4 shafts, 69,906 shp / 52,150 Kw = 30.00 kts\par
Range 9,000nm at 12.00 kts\par
Bunker at max displacement = 1,499 tons\par

Complement:\par
519 - 675\par

Cost:\par
  GBP 2.199 million / $8.798 million\par

Distribution of weights at normal displacement:\par
Armament: 316 tons, 3.0 %\par
Armour: 1,981 tons, 18.8 %\par
   - Belts: 1,062 tons, 10.1 %\par
    - Torpedo bulkhead: 0 tons, 0.0 %\par
    - Armament: 275 tons, 2.6 %\par
    - Armour Deck: 592 tons, 5.6 %\par
    - Conning Tower: 52 tons, 0.5 %\par
Machinery: 2,444 tons, 23.2 %\par
Hull, fittings & equipment: 4,228 tons, 40.1 %\par
Fuel, ammunition & stores: 1,313 tons, 12.5 %\par
Miscellaneous weights: 250 tons, 2.4 %\par

Overall survivability and seakeeping ability:\par
Survivability (Non-critical penetrating hits needed to sink ship):\par
   12,050 lbs / 5,466 Kg = 37.1 x 8.7 " / 220 mm shells or 1.6 torpedoes\par
Stability (Unstable if below 1.00): 1.14\par
Metacentric height 3.5 ft / 1.1 m\par
Roll period: 15.0 seconds\par
Steadiness\tab - As gun platform (Average = 50 %): 70 %\par
- Recoil effect (Restricted arc if above 1.00): 0.42\par
Seaboat quality  (Average = 1.00): 1.01\par

Hull form characteristics:\par
Hull has raised forecastle, rise forward of midbreak\par
Block coefficient: 0.523\par
Length to Beam Ratio: 8.73 : 1\par
'Natural speed' for length: 24.19 kts\par
Power going to wave formation at top speed: 55 %\par
Trim (Max stability = 0, Max steadiness = 100): 69\par
Bow angle (Positive = bow angles forward): 10.00 degrees\par
Stern overhang: 0.00 ft / 0.00 m\par
Freeboard (% = measuring location as a percentage of overall length):\par
    - Stem:\tab\tab 25.00 ft / 7.62 m\par
    - Forecastle (20 %):\tab 23.00 ft / 7.01 m (22.00 ft / 6.71 m aft of break)\par
    - Mid (50 %):\tab\tab 21.00 ft / 6.40 m (13.00 ft / 3.96 m aft of break)\par
    - Quarterdeck (15 %):\tab 13.00 ft / 3.96 m\par
    - Stern:\tab\tab 14.00 ft / 4.27 m\par
    - Average freeboard:\tab 17.79 ft / 5.42 m\par
Ship tends to be wet forward\par

Ship space, strength and comments:\par
Space\tab - Hull below water (magazines/engines, low = better): 101.9 %\par
- Above water (accommodation/working, high = better): 140.0 %\par
Waterplane Area: 26,661 Square feet or 2,477 Square metres\par
Displacement factor (Displacement / loading): 109 %\par
Structure weight / hull surface area: 110 lbs/sq ft or 539 Kg/sq metre\par
Hull strength (Relative):\par
- Cross-sectional: 0.99\par
- Longitudinal: 1.12\par
- Overall: 1.00\par
Hull space for machinery, storage, compartmentation is adequate\par
Room for accommodation and workspaces is excellent\par
Ship has slow, easy roll, a good, steady gun platform\par



  And Finally - Version C - Real Cruising Cruiser - and with more Tonnage going on higher speed + longer range - just 6 x 220mm looks too light in proportion to the investment - so up to 8 x 220mm:


Marauder, BAE Heavy Cruiser laid down 1920

Displacement:
11,819 t light; 12,451 t standard; 14,211 t normal; 15,618 t full load\par

Dimensions: Length overall / water x beam x draught\par
649.76 ft / 645.00 ft x 72.00 ft x 21.00 ft (normal load)\par
198.05 m / 196.60 m x 21.95 m  x 6.40 m\par

Armament:\par
      8 - 8.66" / 220 mm guns (3 mounts), 325.00lbs / 147.42kg shells, 1920 Model\par
   Breech loading guns in turrets (on barbettes)\par
   on centreline ends, majority aft, 1 raised mount aft - superfiring\par
      12 - 4.72" / 120 mm guns (6x2 guns), 55.00lbs / 24.95kg shells, 1920 Model\par
   Quick firing guns in deck mounts with hoists\par
   on side, all amidships, 2 raised mounts - superfiring\par
      4 - 2.76" / 70.0 mm guns in single mounts, 10.50lbs / 4.76kg shells, 1920 Model\par
   Anti-aircraft guns in deck mounts \par
   on side, evenly spread, all raised mounts\par
      24 - 1.00" / 25.4 mm guns (12x2 guns), 0.50lbs / 0.23kg shells, 1920 Model\par
   Machine guns in deck mounts \par
   on side, evenly spread, all raised mounts\par
Weight of broadside 3,314 lbs / 1,503 kg\par
Shells per gun, main battery: 180\par
8 - 22.0" / 558.8 mm above water torpedoes\par

Armour:\par
   - Belts:\tab\tab Width (max)\tab Length (avg)\tab\tab Height (avg)\par
Main:\tab 4.00" / 102 mm\tab 412.00 ft / 125.58 m\tab 12.00 ft / 3.66 m\par
Ends:\tab 1.50" / 38 mm\tab 233.00 ft / 71.02 m\tab 8.00 ft / 2.44 m\par
Upper:\tab 2.00" / 51 mm\tab 250.00 ft / 76.20 m\tab 8.00 ft / 2.44 m\par
   Main Belt covers 98 % of normal length\par

   - Gun armour:\tab Face (max)\tab Other gunhouse (avg)\tab Barbette/hoist (max)\par
Main:\tab 4.00" / 102 mm\tab 2.00" / 51 mm\tab\tab 3.00" / 76 mm\par
2nd:\tab 1.50" / 38 mm\tab 1.20" / 30 mm\tab\tab 1.50" / 38 mm\par
3rd:\tab 0.80" / 20 mm\tab 0.60" / 15 mm\tab\tab       -\par
4th:\tab 0.60" / 15 mm\tab       -\tab\tab\tab       -\par

   - Armour deck: 1.20" / 30 mm, Conning tower: 5.00" / 127 mm\par

Machinery:\par
Oil fired boilers, steam turbines, \par
Geared drive, 4 shafts, 91,154 shp / 68,001 Kw = 31.00 kts\par
Range 10,000nm at 15.00 kts\par
Bunker at max displacement = 3,167 tons\par

Complement:\par
650 - 846\par

Cost:\par
  GBP 2.848 million / $11.391 million\par

Distribution of weights at normal displacement:\par
Armament: 411 tons, 2.9 %\par
Armour: 2,272 tons, 16.0 %\par
    - Belts: 1,124 tons, 7.9 %\par
    - Torpedo bulkhead: 0 tons, 0.0 %\par
    - Armament: 392 tons, 2.8 %\par
    - Armour Deck: 693 tons, 4.9 %\par
    - Conning Tower: 63 tons, 0.4 %\par
Machinery: 3,187 tons, 22.4 %\par
Hull, fittings & equipment: 5,649 tons, 39.8 %\par
Fuel, ammunition & stores: 2,392 tons, 16.8 %\par
Miscellaneous weights: 300 tons, 2.1 %\par

Overall survivability and seakeeping ability:\par
Survivability (Non-critical penetrating hits needed to sink ship):\par
   17,110 lbs / 7,761 Kg = 52.7 x 8.7 " / 220 mm shells or 1.9 torpedoes\par
Stability (Unstable if below 1.00): 1.17\par
Metacentric height 4.1 ft / 1.2 m\par
Roll period: 15.0 seconds\par
Steadiness\tab - As gun platform (Average = 50 %): 71 %\par
- Recoil effect (Restricted arc if above 1.00): 0.46\par
Seaboat quality  (Average = 1.00): 1.12\par

Hull form characteristics:\par
Hull has raised forecastle, rise forward of midbreak\par
Block coefficient: 0.510\par
Length to Beam Ratio: 8.96 : 1\par
'Natural speed' for length: 25.40 kts\par
Power going to wave formation at top speed: 54 %\par
Trim (Max stability = 0, Max steadiness = 100): 63\par
Bow angle (Positive = bow angles forward): 10.00 degrees\par
Stern overhang: 0.00 ft / 0.00 m\par
Freeboard (% = measuring location as a percentage of overall length):\par
    - Stem:\tab\tab 27.00 ft / 8.23 m\par
    - Forecastle (20 %):\tab 25.00 ft / 7.62 m (24.00 ft / 7.32 m aft of break)\par
    - Mid (50 %):\tab\tab 23.00 ft / 7.01 m (15.00 ft / 4.57 m aft of break)\par
    - Quarterdeck (15 %):\tab 15.00 ft / 4.57 m\par
    - Stern:\tab\tab 16.00 ft / 4.88 m\par
    - Average freeboard:\tab 19.79 ft / 6.03 m\par
Ship tends to be wet forward\par

Ship space, strength and comments:\par
Space\tab - Hull below water (magazines/engines, low = better): 98.2 %\par
- Above water (accommodation/working, high = better): 150.6 %\par
Waterplane Area: 31,226 Square feet or 2,901 Square metres\par
Displacement factor (Displacement / loading): 116 %\par
Structure weight / hull surface area: 122 lbs/sq ft or 597 Kg/sq metre\par
Hull strength (Relative):\par
- Cross-sectional: 0.98\par
- Longitudinal: 1.18\par
- Overall: 1.00\par
Hull space for machinery, storage, compartmentation is adequate\par
Room for accommodation and workspaces is excellent\par
Ship has slow, easy roll, a good, steady gun platform\par


  Although the Defensive version is handy sized for the Armament - I think the Larger 2 designs give better return - given the choice I'd go for 4 of each

  - what say you on Smaller Cruisers?


   

[maddox]

France uses the  1908   195 mm  twins and 275mm twins and tripples. 

Also, 10 Ktons is deemed too small for a capital ship, and too expensive for a ship that has to be build in great numbers.
In theory, the French ministry of Defence, under subtil Socialist and enviromentalist politic pressure, has put a cut off at 6500 tons for cruisers max, and for capital ships at 18 000 tons minimum. And those 18 kton desings have to be of superiour capacity before it is even concidered.

[Jefgte]

IMO, the version B is a good compromise.

9000t - 170m - 6x220 - 30kts.


Jef