Iberian Cruiser Designs for 1920

[miketr]

Looking for comments on these designs.  Most likely will lay down a pair of the PC-1920-B design in H2 but I am thinking over my options.

Michael

PC-1920, Iberia Protected Cruiser laid down 1920

Displacement:
   5,496 t light; 5,707 t standard; 6,243 t normal; 6,672 t full load

Dimensions: Length overall / water x beam x draught
   492.13 ft / 492.13 ft x 49.21 ft x 18.04 ft (normal load)
   150.00 m / 150.00 m x 15.00 m  x 5.50 m

Armament:
      8 - 5.91" / 150 mm guns (4x2 guns), 102.98lbs / 46.71kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      8 - 2.95" / 75.0 mm guns in single mounts, 12.87lbs / 5.84kg shells, 1920 Model
     Quick firing guns in deck mounts
     on side, all amidships
      4 - 2.95" / 75.0 mm guns in single mounts, 12.87lbs / 5.84kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
      4 - 0.49" / 12.5 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1920 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 979 lbs / 444 kg
   Shells per gun, main battery: 150
   6 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.95" / 75 mm   367.45 ft / 112.00 m   13.12 ft / 4.00 m
   Ends:   Unarmoured
     Main Belt covers 115 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.95" / 75 mm   1.97" / 50 mm      2.95" / 75 mm
   2nd:   1.97" / 50 mm         -               -
   3rd:   0.98" / 25 mm         -               -

   - Armour deck: 1.57" / 40 mm, Conning tower: 4.72" / 120 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 50,000 shp / 37,300 Kw = 29.65 kts
   Range 11,900nm at 10.00 kts
   Bunker at max displacement = 965 tons

Complement:
   350 - 456

Cost:
   £1.276 million / $5.104 million

Distribution of weights at normal displacement:
   Armament: 122 tons, 2.0 %
   Armour: 1,192 tons, 19.1 %
      - Belts: 580 tons, 9.3 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 107 tons, 1.7 %
      - Armour Deck: 470 tons, 7.5 %
      - Conning Tower: 35 tons, 0.6 %
   Machinery: 1,748 tons, 28.0 %
   Hull, fittings & equipment: 2,234 tons, 35.8 %
   Fuel, ammunition & stores: 747 tons, 12.0 %
   Miscellaneous weights: 200 tons, 3.2 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,193 lbs / 2,809 Kg = 60.1 x 5.9 " / 150 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.22
   Metacentric height 2.5 ft / 0.8 m
   Roll period: 13.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.38
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.500
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 22.18 kts
   Power going to wave formation at top speed: 57 %
   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:      19.69 ft / 6.00 m
      - Forecastle (20 %):   16.40 ft / 5.00 m
      - Mid (50 %):      15.58 ft / 4.75 m
      - Quarterdeck (15 %):   15.58 ft / 4.75 m
      - Stern:      13.12 ft / 4.00 m
      - Average freeboard:   15.95 ft / 4.86 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 109.7 %
      - Above water (accommodation/working, high = better): 114.9 %
   Waterplane Area: 16,136 Square feet or 1,499 Square metres
   Displacement factor (Displacement / loading): 106 %
   Structure weight / hull surface area: 85 lbs/sq ft or 414 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.34
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate

100 tons - 1912 FC
12 tons - Torpedo's
88 tons - construction reserve

PC-1920-a, Iberia Protected Cruiser laid down 1920

Displacement:
   6,000 t light; 6,279 t standard; 6,867 t normal; 7,338 t full load

Dimensions: Length overall / water x beam x draught
   492.13 ft / 492.13 ft x 49.21 ft x 18.04 ft (normal load)
   150.00 m / 150.00 m x 15.00 m  x 5.50 m

Armament:
      8 - 5.91" / 150 mm guns (4x2 guns), 102.98lbs / 46.71kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      6 - 4.72" / 120 mm guns in single mounts, 52.72lbs / 23.92kg shells, 1920 Model
     Quick firing guns in deck mounts
     on side, all amidships
      4 - 2.95" / 75.0 mm guns in single mounts, 12.87lbs / 5.84kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
      4 - 0.49" / 12.5 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1920 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 1,192 lbs / 541 kg
   Shells per gun, main battery: 200
   6 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.95" / 75 mm   374.02 ft / 114.00 m   13.12 ft / 4.00 m
   Ends:   Unarmoured
     Main Belt covers 117 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.95" / 75 mm   1.97" / 50 mm      2.95" / 75 mm
   2nd:   1.97" / 50 mm         -               -
   3rd:   0.98" / 25 mm         -               -

   - Armour deck: 1.57" / 40 mm, Conning tower: 4.72" / 120 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 3 shafts, 58,000 shp / 43,268 Kw = 30.13 kts
   Range 12,400nm at 10.00 kts
   Bunker at max displacement = 1,058 tons

Complement:
   376 - 490

Cost:
   £1.463 million / $5.853 million

Distribution of weights at normal displacement:
   Armament: 149 tons, 2.2 %
   Armour: 1,235 tons, 18.0 %
      - Belts: 591 tons, 8.6 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 115 tons, 1.7 %
      - Armour Deck: 492 tons, 7.2 %
      - Conning Tower: 37 tons, 0.5 %
   Machinery: 2,028 tons, 29.5 %
   Hull, fittings & equipment: 2,388 tons, 34.8 %
   Fuel, ammunition & stores: 867 tons, 12.6 %
   Miscellaneous weights: 201 tons, 2.9 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,116 lbs / 2,774 Kg = 59.4 x 5.9 " / 150 mm shells or 1.0 torpedoes
   Stability (Unstable if below 1.00): 1.22
   Metacentric height 2.5 ft / 0.8 m
   Roll period: 13.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.44
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.550
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 22.18 kts
   Power going to wave formation at top speed: 59 %
   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:      21.33 ft / 6.50 m
      - Forecastle (20 %):   18.04 ft / 5.50 m
      - Mid (50 %):      17.22 ft / 5.25 m
      - Quarterdeck (15 %):   15.58 ft / 4.75 m
      - Stern:      14.76 ft / 4.50 m
      - Average freeboard:   17.18 ft / 5.24 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 116.5 %
      - Above water (accommodation/working, high = better): 120.5 %
   Waterplane Area: 16,902 Square feet or 1,570 Square metres
   Displacement factor (Displacement / loading): 103 %
   Structure weight / hull surface area: 85 lbs/sq ft or 414 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.46
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent

100 tons - 1912 FC
12 tons - Torpedo's
89 tons - construction reserve

PC-1920-b, Iberia Protected Cruiser laid down 1920

Displacement:
   5,999 t light; 6,275 t standard; 6,867 t normal; 7,341 t full load

Dimensions: Length overall / water x beam x draught
   492.13 ft / 492.13 ft x 49.21 ft x 18.04 ft (normal load)
   150.00 m / 150.00 m x 15.00 m  x 5.50 m

Armament:
      8 - 5.91" / 150 mm guns (4x2 guns), 102.98lbs / 46.71kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on centreline ends, evenly spread, 2 raised mounts - superfiring
      8 - 4.13" / 105 mm guns in single mounts, 35.32lbs / 16.02kg shells, 1920 Model
     Quick firing guns in deck mounts
     on side, all amidships
      4 - 2.95" / 75.0 mm guns in single mounts, 12.87lbs / 5.84kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, all amidships, all raised mounts - superfiring
      4 - 0.49" / 12.5 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1920 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 1,158 lbs / 525 kg
   Shells per gun, main battery: 200
   6 - 21.0" / 533.4 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   2.95" / 75 mm   374.02 ft / 114.00 m   13.12 ft / 4.00 m
   Ends:   Unarmoured
     Main Belt covers 117 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.95" / 75 mm   1.97" / 50 mm      2.95" / 75 mm
   2nd:   1.97" / 50 mm         -               -
   3rd:   0.98" / 25 mm         -               -

   - Armour deck: 1.57" / 40 mm, Conning tower: 4.72" / 120 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 3 shafts, 58,000 shp / 43,268 Kw = 30.13 kts
   Range 12,500nm at 10.00 kts
   Bunker at max displacement = 1,066 tons

Complement:
   376 - 490

Cost:
   £1.455 million / $5.819 million

Distribution of weights at normal displacement:
   Armament: 145 tons, 2.1 %
   Armour: 1,239 tons, 18.0 %
      - Belts: 591 tons, 8.6 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 119 tons, 1.7 %
      - Armour Deck: 492 tons, 7.2 %
      - Conning Tower: 37 tons, 0.5 %
   Machinery: 2,028 tons, 29.5 %
   Hull, fittings & equipment: 2,381 tons, 34.7 %
   Fuel, ammunition & stores: 868 tons, 12.6 %
   Miscellaneous weights: 207 tons, 3.0 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6,154 lbs / 2,792 Kg = 59.8 x 5.9 " / 150 mm shells or 1.0 torpedoes
   Stability (Unstable if below 1.00): 1.22
   Metacentric height 2.5 ft / 0.8 m
   Roll period: 13.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.43
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.550
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 22.18 kts
   Power going to wave formation at top speed: 59 %
   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:      21.33 ft / 6.50 m
      - Forecastle (20 %):   18.04 ft / 5.50 m
      - Mid (50 %):      17.22 ft / 5.25 m
      - Quarterdeck (15 %):   15.58 ft / 4.75 m
      - Stern:      14.76 ft / 4.50 m
      - Average freeboard:   17.18 ft / 5.24 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 116.1 %
      - Above water (accommodation/working, high = better): 120.5 %
   Waterplane Area: 16,902 Square feet or 1,570 Square metres
   Displacement factor (Displacement / loading): 103 %
   Structure weight / hull surface area: 85 lbs/sq ft or 413 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.95
      - Longitudinal: 1.46
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is excellent

100 tons - 1912 FC
12 tons - Torpedo's
95 tons - construction reserve

[Guinness]

I don't think you need the 75mm, 105mm, or 120mm guns at all. If it were me, I'd be tempted to delete them and either add 150mm guns, or reduce size while maintaining the other attributes.

I'm not sure 30 knots is fast enough for a light cruiser at this point, but I suppose that's up to those drawing requirements for the Iberian Navy. 31+ knots is probably costly.

[miketr]

I think some secondary battery is needed.  I did debate doing a cruiser design with all 120mm guns.  Deleting the 105's doesn't allow much of change in displacement, they don't need much mass.

As to speed I did this cruiser list some time ago.

http://www.navalism.org/index.php?topic=4908.msg58534#msg58534

There isn't all that many designs out there faster than 30 knots.  I built a class of 4 ships able to do 32.5 knots but they were expensive.  So I wanted to do a smaller design.

In few years I expect to move back to a 32 knot design, but the problem is that extra 2 knots costs a lot of displacement.

Michael

[Jefgte]

I agree Mike, 32kts cost too much actualy.
NUS built actualy 2x 32kts CLs but the next class 'll be slower - 27 to 30kts.

30kts is a correct speed for Iberia, I think.
You have AB-XY 150mm turret
Did you instal a group with 120mm to engage a 3rd target (DD) ?
You could install too QF40mm AA.


Jef

[Sachmle]

I'm in with Guinness, I'd drop the 75/105/120s. Knowing, since you said so, this won't save much tonnage I'd replace them with 4 singe 150s. That makes a 10 gun broadside..pretty nasty for 6k.

[ctwaterman]

I dont know speed is useful for say outrunning those 27 to 30 Knot Battle Cruisers for that Speed of 32+ Knots is needed.   But as an example the Italia Taranto Class 5 Strong simply does not want to catch a 30 Knot Cruiser armed with 5.9 Guns.  I mean you caught it now what are you going to do with it...??

I think the Secondary Guns could be damn useful for engaging numbers of Torpedo Boats and or Destroyers.   In the Battles in the Rift the New Swiss were able to concentrate their Destroyers and force their way close enough to the capital ships to launch 18" torpedoes at them.   The only lesson to be learned from this is more and better secondaries on even the cruisers to help beat off such massed attacks.

Of course speed is just plain neat as well and I am sure the larger Nations with BP to burn will soon be trying to crank out a 34+ Knot Cruiser.

[miketr]

It is a question of costs vs. need. It would be NICE to build another 32.5 knot cruiser but the expense would be high and Iberia needs more patrol  cruisers, IE numbers.

Michael

[Jefgte]

6000t
30kts with 4T2x150 or 27-28kts with a powerfull armament.


Jef

[P3D]

If you are not that worried about speed, then I'd build 28kts cruisers to support your existing patrol fleet. 4500t, 8x150, 120m long.

From savings build 1-2 extra 32.5kts cruisers.

[Jefgte]

The emergency NUS CL project is similar too.
4000t - 120m - 4T2x6" - 27kts - B80mm - D30mm.

---------------------
You could test a light AC, a kind of light Exeter.
6x205 - 27kts - B3"


Jef

[Jefgte]

Testing a 120m lenght with 2T3x230 @27kts with a CL protection.
Note that the hull is stressed (recoil 0.82) but if you rework with your 205mm guns, you could have a correct cruiser made to work with the other cruisers or the battleline.

AC, NUS 6x230 laid down 1920 (Engine 1916)

Displacement:
   5 850 t light; 6 198 t standard; 6 981 t normal; 7 608 t full load

Dimensions: Length overall / water x beam x draught
   393.70 ft / 393.70 ft x 55.12 ft x 21.33 ft (normal load)
   120.00 m / 120.00 m x 16.80 m  x 6.50 m

Armament:
      6 - 9.06" / 230 mm guns (2x3 guns), 371.24lbs / 168.39kg shells, 1920 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, evenly spread
      4 - 4.72" / 120 mm guns (2x2 guns), 52.72lbs / 23.92kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on side, evenly spread
      4 - 1.57" / 40.0 mm guns (2x2 guns), 1.95lbs / 0.89kg shells, 1920 Model
     Quick firing guns in deck mounts
     on side, evenly spread, all raised mounts
      4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1920 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 2 446 lbs / 1 110 kg
   Shells per gun, main battery: 150
   6 - 21.0" / 533 mm above water torpedoes

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.15" / 80 mm   288.71 ft / 88.00 m   10.00 ft / 3.05 m
   Ends:   1.57" / 40 mm     72.18 ft / 22.00 m   8.01 ft / 2.44 m
     32.81 ft / 10.00 m Unarmoured ends
     Main Belt covers 113 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   3.94" / 100 mm   1.97" / 50 mm      3.15" / 80 mm
   2nd:   1.57" / 40 mm   0.79" / 20 mm      1.57" / 40 mm
   3rd:   0.79" / 20 mm         -               -
   4th:   0.50" / 13 mm         -               -

   - Armour deck: 1.18" / 30 mm, Conning tower: 3.15" / 80 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 43 195 shp / 32 223 Kw = 27.00 kts
   Range 10 000nm at 12.00 kts
   Bunker at max displacement = 1 410 tons

Complement:
   381 - 496

Cost:
   £1.624 million / $6.495 million

Distribution of weights at normal displacement:
   Armament: 306 tons, 4.4 %
   Armour: 1 003 tons, 14.4 %
      - Belts: 415 tons, 5.9 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 239 tons, 3.4 %
      - Armour Deck: 324 tons, 4.6 %
      - Conning Tower: 25 tons, 0.4 %
   Machinery: 1 609 tons, 23.1 %
   Hull, fittings & equipment: 2 732 tons, 39.1 %
   Fuel, ammunition & stores: 1 131 tons, 16.2 %
   Miscellaneous weights: 200 tons, 2.9 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     6 234 lbs / 2 828 Kg = 16.8 x 9.1 " / 230 mm shells or 1.1 torpedoes
   Stability (Unstable if below 1.00): 1.10
   Metacentric height 2.5 ft / 0.7 m
   Roll period: 14.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 51 %
         - Recoil effect (Restricted arc if above 1.00): 0.82
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.528
   Length to Beam Ratio: 7.14 : 1
   'Natural speed' for length: 19.84 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 51
   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:      24.28 ft / 7.40 m
      - Forecastle (22 %):   21.65 ft / 6.60 m
      - Mid (50 %):      17.72 ft / 5.40 m
      - Quarterdeck (20 %):   17.72 ft / 5.40 m
      - Stern:      17.72 ft / 5.40 m
      - Average freeboard:   19.36 ft / 5.90 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 111.7 %
      - Above water (accommodation/working, high = better): 112.1 %
   Waterplane Area: 14 836 Square feet or 1 378 Square metres
   Displacement factor (Displacement / loading): 102 %
   Structure weight / hull surface area: 108 lbs/sq ft or 527 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.88
      - Longitudinal: 3.15
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is cramped
   Room for accommodation and workspaces is adequate

[Jefgte]

An other one with the T2x194-50cal Mlle 1915 from GC  ;)

5800T, Iberian CL laid down 1920 (Engine 1916)

Displacement:
   5 800 t light; 6 207 t standard; 6 992 t normal; 7 621 t full load

Dimensions: Length overall / water x beam x draught
   393.70 ft / 393.70 ft x 55.45 ft x 20.38 ft (normal load)
   120.00 m / 120.00 m x 16.90 m  x 6.21 m

Armament:
     6 - 7.64" / 194 mm guns (3x2 guns), 220.46lbs / 100.00kg shells, 1915 Model
     Breech loading guns in turrets (on barbettes)
     on centreline ends, majority forward, 1 raised mount - superfiring
     8 - 4.72" / 120 mm guns (4x2 guns), 52.72lbs / 23.92kg shells, 1920 Model
     Breech loading guns in deck mounts with hoists
     on side, all amidships
     4 - 1.57" / 40.0 mm guns (2x2 guns), 1.95lbs / 0.89kg shells, 1920 Model
     Anti-aircraft guns in deck mounts
     on side, evenly spread, all raised mounts
     4 - 0.50" / 12.7 mm guns in single mounts, 0.06lbs / 0.03kg shells, 1920 Model
     Machine guns in deck mounts
     on side, evenly spread, all raised mounts
   Weight of broadside 1 753 lbs / 795 kg
   Shells per gun, main battery: 260
   6 - 21.0" / 533.4 mm above water torpedoes

Armour:
  - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.15" / 80 mm   275.59 ft / 84.00 m   11.00 ft / 3.35 m
   Ends:   1.57" / 40 mm     98.43 ft / 30.00 m   8.01 ft / 2.44 m
     19.69 ft / 6.00 m Unarmoured ends
     Main Belt covers 108 % of normal length

  - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   3.94" / 100 mm   1.97" / 50 mm      3.15" / 80 mm
   2nd:   1.97" / 50 mm   0.79" / 20 mm      1.97" / 50 mm
   3rd:   0.79" / 20 mm         -               -
   4th:   0.50" / 13 mm         -               -

  - Armour deck: 1.18" / 30 mm, Conning tower: 3.15" / 80 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 44 000 shp / 32 824 Kw = 27.03 kts
   Range 10 000nm at 12.00 kts
   Bunker at max displacement = 1 414 tons

Complement:
   382 - 497

Cost:
   £1.461 million / $5.843 million

Distribution of weights at normal displacement:
   Armament: 221 tons, 3.2 %
   Armour: 1 079 tons, 15.4 %
      - Belts: 451 tons, 6.5 %
      - Torpedo bulkhead: 0 tons, 0.0 %
      - Armament: 270 tons, 3.9 %
      - Armour Deck: 333 tons, 4.8 %
      - Conning Tower: 25 tons, 0.4 %
   Machinery: 1 639 tons, 23.4 %
   Hull, fittings & equipment: 2 561 tons, 36.6 %
   Fuel, ammunition & stores: 1 192 tons, 17.1 %
   Miscellaneous weights: 300 tons, 4.3 %

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     7 020 lbs / 3 184 Kg = 31.5 x 7.6 " / 194 mm shells or 1.2 torpedoes
   Stability (Unstable if below 1.00): 1.10
   Metacentric height 2.5 ft / 0.8 m
   Roll period: 14.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.64
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck
   Block coefficient: 0.550
   Length to Beam Ratio: 7.10 : 1
   'Natural speed' for length: 19.84 kts
   Power going to wave formation at top speed: 64 %
   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:      24.93 ft / 7.60 m
      - Forecastle (22 %):   21.65 ft / 6.60 m
      - Mid (50 %):      18.37 ft / 5.60 m
      - Quarterdeck (20 %):   18.37 ft / 5.60 m
      - Stern:      18.37 ft / 5.60 m
      - Average freeboard:   19.84 ft / 6.05 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 107.1 %
      - Above water (accommodation/working, high = better): 118.0 %
   Waterplane Area: 15 234 Square feet or 1 415 Square metres
   Displacement factor (Displacement / loading): 109 %
   Structure weight / hull surface area: 99 lbs/sq ft or 486 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.89
      - Longitudinal: 2.92
      - Overall: 1.00
   Hull space for machinery, storage, compartmentation is adequate
   Room for accommodation and workspaces is adequate

[miketr]

30  knots is good enough for right now and the future.  28 knots was good a few years back.

I am debating building a few more 2K ton patrol gun boats.

If I builder a more powerful cruiser I build something with 250mm guns.  Have or will have an L55 weapon shortly.

Michael

[mentat]

All are good designs - but not sure about 8 x 75mm - too many 'pop-guns'

Agree for general patrol purposes 30 knots is good - good bunkerage to be able to keep up the speed is just as important as more speed

wondering on a few points:

  - possible to go to Turret + Barbette - better protection, higher sustained RoF + better in poor weather?

   - considering possibility of mine-laying capacity? - there is some reserve weight there

- would higher steadiness be useful vs. the high stability level

+ I favour the 120 mm secrs - more useful - but still keep 8

   

    look forward to seeing the 250 mm AC design some time - Big ACs my favourite  :D