Another gunboat for Red Sea & all Indian ocean colonial places.

TGB1280, Byzantine Empire TGB1280 laid down 1937
Displacement:
   1 280 t light; 1 385 t standard; 1 527 t normal; 1 640 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (325,78 ft / 321,52 ft) x 33,46 ft x (10,94 / 11,52 ft)
   (99,30 m / 98,00 m) x 10,20 m  x (3,33 / 3,51 m)

Armament:
      4 - 5,24" / 133 mm 50,0 cal guns - 80,01lbs / 36,29kg shells, 340 per gun
     Dual purpose guns in deck mounts, 1937 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 1 500 per gun
     Anti-air guns in deck mounts, 1937 Model
     4 x 2-gun mounts on centreline, aft deck aft
      2 raised mounts - superfiring
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 1 500 per gun
     Anti-air guns in deck mounts, 1937 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      2 raised mounts
      4 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 3 000 per gun
     Machine guns in deck mounts, 1937 Model
     2 x 2-gun mounts on sides, forward deck centre
      2 raised mounts
      Weight of broadside 336 lbs / 153 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,39" / 10 mm         -               -
   2nd:   0,24" / 6 mm         -               -
   3rd:   0,24" / 6 mm         -               -
   4th:   0,24" / 6 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Electric motors, 2 shafts, 26 315 shp / 19 631 Kw = 30,00 kts
   Range 6 000nm at 12,00 kts
   Bunker at max displacement = 256 tons

Complement:
   121 - 158

Cost:
   £0,859 million / $3,436 million

Distribution of weights at normal displacement:
   Armament: 66 tons, 4,4 %
      - Guns: 66 tons, 4,4 %
   Armour: 4 tons, 0,3 %
      - Armament: 4 tons, 0,3 %
   Machinery: 684 tons, 44,8 %
   Hull, fittings & equipment: 474 tons, 31,1 %
   Fuel, ammunition & stores: 247 tons, 16,2 %
   Miscellaneous weights: 51 tons, 3,3 %
      - On freeboard deck: 44 tons
      - Above deck: 7 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     659 lbs / 299 Kg = 9,2 x 5,2 " / 133 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,17
   Metacentric height 1,3 ft / 0,4 m
   Roll period: 12,4 seconds
   Steadiness   - As gun platform (Average = 50 %): 72 %
         - Recoil effect (Restricted arc if above 1.00): 0,34
   Seaboat quality  (Average = 1.00): 1,04

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0,454 / 0,463
   Length to Beam Ratio: 9,61 : 1
   'Natural speed' for length: 17,93 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 69
   Bow angle (Positive = bow angles forward): 12,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   22,00 %,  20,01 ft / 6,10 m,  16,24 ft / 4,95 m
      - Forward deck:   30,00 %,  16,24 ft / 4,95 m,  12,63 ft / 3,85 m
      - Aft deck:   28,00 %,  12,63 ft / 3,85 m,  11,65 ft / 3,55 m
      - Quarter deck:   20,00 %,  11,65 ft / 3,55 m,  11,65 ft / 3,55 m
      - Average freeboard:      13,96 ft / 4,26 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 159,2 %
      - Above water (accommodation/working, high = better): 136,5 %
   Waterplane Area: 6 886 Square feet or 640 Square metres
   Displacement factor (Displacement / loading): 91 %
   Structure weight / hull surface area: 40 lbs/sq ft or 196 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,66
      - Longitudinal: 2,26
      - Overall: 0,75
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

AD
0t for SR Marconi
7t for 1930 fire control
OD
12 tons for 4TTx533
10t for 1930 sonar
5t for 50 DC
2t for 2xY  DC
15t reserve for paravanes, new material, armament.
HA
climatisation

Interesting little Cruiser. Could work as a Destroyer Escort very easily.

I suspect it started as a Destroyer and the engines were de-rated to get  to 0.75
It does have 'Electric Drive' toggled, and no weight set aside for it.

Quote from: The Rock Doctor on February 01, 2025, 11:33:53 AMThe destroyer looks good.

I don't care for the cruiser's belt height or speed, but it's 2,000 t smaller than what I built, so the economics may be favorable.

We've never really settled on 'good amount' for Night fighting.
I figure some searchlights and a light starshell projector come with the hull, fittings & equipment.
The low end is random tonnage allocated.
'adequate' is equal to FC up to 25t
and 25t+ is the RN's searchlight tower or equivalent.

So 5t vs 6 for FC is from my perspective, which is an unofficial one, a little odd.

As for the Cruiser, it reminds me of one of the Martime Patrol Frigate options I posted a while back.
It's quite hard to make the weights work at that range.

Presuming the weatherdeck aft at 4.72m has a standard 2.44m deck under it (Parthian are typically 2.5),
then the next deck  is at 2.28m, and the belt covers to -0.42m.
That seems a little shallow.
Presumable short range action vs. QF guns is expected, so it does not need to be battleship-deep, but
I think the lowest I have gone is 0.5, but 0.75 or 1.0 is more typical for cruiser-types.

I know the faster a ship goes, the wave period along the side matters, as the troughs may expose the lower edge of the hull, and then the roll side to side can expose some.  I do not know how to calculate that though.

Speedwise both the Parthians and Byzantines are slow compared to many*. 30 knots means that my cruisers up through the Royal Nissean class can not over take.

*I find the guns/armor/speed trade offs fascinating :)

Quote...It does have 'Electric Drive' toggled, and no weight set aside for it...

SS corrected
"Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 26 315 shp / 19 631 Kw = 30,00 kts
   Range 6 000nm at 12,00 kts
   Bunker at max displacement = 256 tons"

---------------------

Considering the Byzantine colonies spread across the world, I prefer 3 x 1330t TGB to 1 x 4000t cruiser

I fielded the Sibari class for a while, and then dropped down to the Hukar as more affordable.
The issue I had was that instead of 2 Hukars for 1 Sibari...I built 1 Hukar a year.

The rate of fire of the 3T2x133 and the maximum range of 21,000m are a significant advantages for this 30kt colonial gunboat, less than 1,500t.

TGB1440, Byzantine Empire 30kts TGB laid down 1937

Displacement:
    1 440 t light; 1 583 t standard; 1 712 t normal; 1 815 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
    (338,97 ft / 334,65 ft) x 35,24 ft x (10,91 / 11,38 ft)
    (103,32 m / 102,00 m) x 10,74 m  x (3,32 / 3,47 m)

Armament:
      6 - 5,24" / 133 mm 50,0 cal guns - 80,01lbs / 36,29kg shells, 340 per gun
      Dual purpose guns in deck mounts, 1937 Model
      3 x 2-gun mounts on centreline ends, majority forward
        1 raised mount - superfiring
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
      Anti-air guns in deck mounts, 1937 Model
      2 x 2-gun mounts on sides, forward deck centre
        2 raised mounts
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
      Anti-air guns in deck mounts, 1937 Model
      2 x 2-gun mounts on sides, aft deck aft
        2 raised mounts
      4 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 3 000 per gun
      Machine guns in deck mounts, 1937 Model
      2 x 2-gun mounts on sides, forward deck centre
        2 raised mounts
      Weight of broadside 496 lbs / 225 kg

Armour:
  - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    0,79" / 20 mm          -                  -
    2nd:    0,24" / 6 mm          -                  -
    3rd:    0,24" / 6 mm          -                  -
    4th:    0,24" / 6 mm          -                  -

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 2 shafts, 27 957 shp / 20 856 Kw = 30,00 kts
    Range 5 000nm at 12,00 kts
    Bunker at max displacement = 232 tons

Complement:
    133 - 173

Cost:
    £0,973 million / $3,892 million

Distribution of weights at normal displacement:
    Armament: 98 tons, 5,7 %
      - Guns: 98 tons, 5,7 %
    Armour: 9 tons, 0,5 %
      - Armament: 9 tons, 0,5 %
    Machinery: 736 tons, 43,0 %
    Hull, fittings & equipment: 541 tons, 31,6 %
    Fuel, ammunition & stores: 272 tons, 15,9 %
    Miscellaneous weights: 57 tons, 3,3 %
      - On freeboard deck: 47 tons
      - Above deck: 10 tons

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      767 lbs / 348 Kg = 10,7 x 5,2 " / 133 mm shells or 0,4 torpedoes
    Stability (Unstable if below 1.00): 1,16
    Metacentric height 1,4 ft / 0,4 m
    Roll period: 12,6 seconds
    Steadiness    - As gun platform (Average = 50 %): 71 %
            - Recoil effect (Restricted arc if above 1.00): 0,49
    Seaboat quality  (Average = 1.00): 1,07

Hull form characteristics:
    Hull has a flush deck,
      a ram bow and a cruiser stern
    Block coefficient (normal/deep): 0,466 / 0,473
    Length to Beam Ratio: 9,50 : 1
    'Natural speed' for length: 18,29 kts
    Power going to wave formation at top speed: 66 %
    Trim (Max stability = 0, Max steadiness = 100): 66
    Bow angle (Positive = bow angles forward): 12,00 degrees
    Stern overhang: 0,00 ft / 0,00 m
    Freeboard (% = length of deck as a percentage of waterline length):
                Fore end,    Aft end
      - Forecastle:    22,00 %,  20,34 ft / 6,20 m,  16,73 ft / 5,10 m
      - Forward deck:    30,00 %,  16,73 ft / 5,10 m,  13,12 ft / 4,00 m
      - Aft deck:    28,00 %,  13,12 ft / 4,00 m,  12,80 ft / 3,90 m
      - Quarter deck:    20,00 %,  12,80 ft / 3,90 m,  12,80 ft / 3,90 m
      - Average freeboard:        14,66 ft / 4,47 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 157,8 %
        - Above water (accommodation/working, high = better): 142,9 %
    Waterplane Area: 7 623 Square feet or 708 Square metres
    Displacement factor (Displacement / loading): 92 %
    Structure weight / hull surface area: 43 lbs/sq ft or 211 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0,66
        - Longitudinal: 2,28
        - Overall: 0,75
    Cramped machinery, storage, compartmentation space
    Excellent accommodation and workspace room
    Ship has slow, easy roll, a good, steady gun platform

AD
0t for SR Marconi
10t for 1930 fire control
OD
12 tons for 4TTx533
10t for 1930 sonar
5t for 50 DC
2t for 2xY  DC
18t reserve for paravanes, new material, armament.
HA
climatisation

133/50 need mount and hoist to maintain the rate of fire with 36kg shells.
BP reserve allows me to go up to 1500t and 6000nm range.
I think they are excellent defenders for colonies and good support for MTB attacks.

Torpedo Gun Boat, Byzantine Empire TGB1500 laid down 1937

Displacement:
    1 500 t light; 1 610 t standard; 1 765 t normal; 1 890 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
    (338,97 ft / 334,65 ft) x 36,09 ft x (11,52 / 12,09 ft)
    (103,32 m / 102,00 m) x 11,00 m  x (3,51 / 3,68 m)

Armament:
      4 - 5,24" / 133 mm 50,0 cal guns - 80,01lbs / 36,29kg shells, 340 per gun
      Dual purpose guns in deck and hoist mounts, 1937 Model
      2 x 2-gun mounts on centreline ends, evenly spread
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 1 500 per gun
      Anti-air guns in deck mounts, 1937 Model
      2 x 2-gun mounts on sides, forward deck aft
        2 raised mounts
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 1 500 per gun
      Anti-air guns in deck mounts, 1937 Model
      2 x 2-gun mounts on centreline ends, evenly spread
        2 raised mounts
      4 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 3 000 per gun
      Machine guns in deck mounts, 1937 Model
      2 x 2-gun mounts on sides, forward deck centre
        2 raised mounts
      Weight of broadside 336 lbs / 153 kg

Armour:
  - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    0,98" / 25 mm    0,59" / 15 mm        0,59" / 15 mm
    2nd:    0,24" / 6 mm          -                  -
    3rd:    0,24" / 6 mm          -                  -
    4th:    0,24" / 6 mm          -                  -

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 2 shafts, 28 211 shp / 21 046 Kw = 30,00 kts
    Range 6 000nm at 12,00 kts
    Bunker at max displacement = 280 tons

Complement:
    136 - 177

Cost:
    £1,028 million / $4,113 million

Distribution of weights at normal displacement:
    Armament: 100 tons, 5,7 %
      - Guns: 100 tons, 5,7 %
    Armour: 12 tons, 0,7 %
      - Armament: 12 tons, 0,7 %
    Machinery: 736 tons, 41,7 %
    Hull, fittings & equipment: 603 tons, 34,2 %
    Fuel, ammunition & stores: 265 tons, 15,0 %
    Miscellaneous weights: 49 tons, 2,8 %
      - On freeboard deck: 39 tons
      - Above deck: 10 tons

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      782 lbs / 355 Kg = 10,9 x 5,2 " / 133 mm shells or 0,4 torpedoes
    Stability (Unstable if below 1.00): 1,08
    Metacentric height 1,3 ft / 0,4 m
    Roll period: 13,5 seconds
    Steadiness    - As gun platform (Average = 50 %): 70 %
            - Recoil effect (Restricted arc if above 1.00): 0,55
    Seaboat quality  (Average = 1.00): 1,02

Hull form characteristics:
    Hull has a flush deck,
      a ram bow and a cruiser stern
    Block coefficient (normal/deep): 0,444 / 0,453
    Length to Beam Ratio: 9,27 : 1
    'Natural speed' for length: 18,29 kts
    Power going to wave formation at top speed: 65 %
    Trim (Max stability = 0, Max steadiness = 100): 69
    Bow angle (Positive = bow angles forward): 12,00 degrees
    Stern overhang: 0,00 ft / 0,00 m
    Freeboard (% = length of deck as a percentage of waterline length):
                Fore end,    Aft end
      - Forecastle:    22,00 %,  20,34 ft / 6,20 m,  16,73 ft / 5,10 m
      - Forward deck:    30,00 %,  16,73 ft / 5,10 m,  13,12 ft / 4,00 m
      - Aft deck:    28,00 %,  13,12 ft / 4,00 m,  12,80 ft / 3,90 m
      - Quarter deck:    20,00 %,  12,80 ft / 3,90 m,  12,80 ft / 3,90 m
      - Average freeboard:        14,66 ft / 4,47 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 154,8 %
        - Above water (accommodation/working, high = better): 140,6 %
    Waterplane Area: 7 666 Square feet or 712 Square metres
    Displacement factor (Displacement / loading): 91 %
    Structure weight / hull surface area: 47 lbs/sq ft or 230 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0,66
        - Longitudinal: 2,27
        - Overall: 0,75
    Cramped machinery, storage, compartmentation space
    Excellent accommodation and workspace room
    Ship has slow, easy roll, a good, steady gun platform

AD
0t for SR Marconi
10t for 1930 fire control
OD
9 tons for 3TTx533
5t for night fighting
10t for 1930 sonar
5t for 50 x 90kg DC
2t for 2xY  DC
8t reserve for paravanes, new material, armament.
HA
climatisation

Stronger than the last 4000t with 3T2x152 design.

AGB7000, Byzantine Empire Red Sea Armored Gun Boat laid down 1937

Displacement:
    7 000 t light; 7 422 t standard; 7 836 t normal; 8 168 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
    (541,65 ft / 538,06 ft) x 59,78 ft x (16,56 / 17,08 ft)
    (165,10 m / 164,00 m) x 18,22 m  x (5,05 / 5,21 m)

Armament:
      6 - 7,52" / 191 mm 45,0 cal guns - 240,00lbs / 108,86kg shells, 135 per gun
      Breech loading guns in turret on barbette mounts, 1937 Model
      2 x 3-gun mounts on centreline ends, evenly spread
      8 - 5,24" / 133 mm 45,0 cal guns - 80,01lbs / 36,29kg shells, 340 per gun
      Dual purpose guns in deck and hoist mounts, 1937 Model
      4 x 2-gun mounts on sides, evenly spread
      16 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
      Anti-air guns in deck mounts, 1937 Model
      4 x 4-gun mounts on side ends, evenly spread
        4 raised mounts
      8 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 4 000 per gun
      Machine guns in deck mounts, 1937 Model
      4 x 2-gun mounts on sides, forward evenly spread
        4 raised mounts
      Weight of broadside 2 113 lbs / 958 kg

Armour:
  - Belts:        Width (max)    Length (avg)        Height (avg)
    Main:    3,94" / 100 mm    349,74 ft / 106,60 m    9,28 ft / 2,83 m
    Ends:    0,98" / 25 mm    188,29 ft / 57,39 m    9,28 ft / 2,83 m
      Main Belt covers 100 % of normal length

  - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    5,91" / 150 mm    2,36" / 60 mm        3,94" / 100 mm
    2nd:    0,98" / 25 mm    0,79" / 20 mm        0,79" / 20 mm
    3rd:    0,24" / 6 mm          -                  -
    4th:    0,24" / 6 mm          -                  -

  - Armoured deck - single deck:
    For and Aft decks: 1,77" / 45 mm
    Forecastle: 0,98" / 25 mm  Quarter deck: 1,57" / 40 mm

  - Conning towers: Forward 3,94" / 100 mm, Aft 0,98" / 25 mm

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 4 shafts, 55 050 shp / 41 067 Kw = 30,00 kts
    Range 6 000nm at 12,00 kts
    Bunker at max displacement = 746 tons

Complement:
    416 - 541

Cost:
    £3,471 million / $13,882 million

Distribution of weights at normal displacement:
    Armament: 535 tons, 6,8 %
      - Guns: 535 tons, 6,8 %
    Armour: 1 572 tons, 20,1 %
      - Belts: 595 tons, 7,6 %
      - Armament: 234 tons, 3,0 %
      - Armour Deck: 702 tons, 9,0 %
      - Conning Towers: 42 tons, 0,5 %
    Machinery: 1 526 tons, 19,5 %
    Hull, fittings & equipment: 3 145 tons, 40,1 %
    Fuel, ammunition & stores: 837 tons, 10,7 %
    Miscellaneous weights: 222 tons, 2,8 %
      - Hull below water: 30 tons
      - On freeboard deck: 119 tons
      - Above deck: 73 tons

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      11 215 lbs / 5 087 Kg = 52,7 x 7,5 " / 191 mm shells or 1,7 torpedoes
    Stability (Unstable if below 1.00): 1,03
    Metacentric height 2,4 ft / 0,7 m
    Roll period: 16,1 seconds
    Steadiness    - As gun platform (Average = 50 %): 70 %
            - Recoil effect (Restricted arc if above 1.00): 0,63
    Seaboat quality  (Average = 1.00): 1,03

Hull form characteristics:
    Hull has a flush deck,
      a normal bow and small transom stern
    Block coefficient (normal/deep): 0,515 / 0,520
    Length to Beam Ratio: 9,00 : 1
    'Natural speed' for length: 24,98 kts
    Power going to wave formation at top speed: 56 %
    Trim (Max stability = 0, Max steadiness = 100): 68
    Bow angle (Positive = bow angles forward): 8,00 degrees
    Stern overhang: 0,00 ft / 0,00 m
    Freeboard (% = length of deck as a percentage of waterline length):
                Fore end,    Aft end
      - Forecastle:    17,50 %,  25,59 ft / 7,80 m,  21,00 ft / 6,40 m
      - Forward deck:    32,50 %,  21,00 ft / 6,40 m,  16,93 ft / 5,16 m
      - Aft deck:    32,50 %,  16,93 ft / 5,16 m,  16,60 ft / 5,06 m
      - Quarter deck:    17,50 %,  16,60 ft / 5,06 m,  16,60 ft / 5,06 m
      - Average freeboard:        18,51 ft / 5,64 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 86,7 %
        - Above water (accommodation/working, high = better): 182,0 %
    Waterplane Area: 22 251 Square feet or 2 067 Square metres
    Displacement factor (Displacement / loading): 120 %
    Structure weight / hull surface area: 105 lbs/sq ft or 513 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0,96
        - Longitudinal: 1,42
        - Overall: 1,00
    Adequate machinery, storage, compartmentation space
    Excellent accommodation and workspace room
    Ship has slow, easy roll, a good, steady gun platform

AD
Short Range Marconi
53t for top mast rangefinder - FC1930
20t for Hulesmeyer
OD
24t for 2 x 3 TT x 21" HW
25t for Seaplane + cata
10t for night fighting
15t for enhanced hydrophone
5t for DC
20t for flag Ship
20t reserved for new materials, armaments.
AW
Climatisation
BW
30t for additionnal pumps

For a 25kts TGB speed, the machines became lighter.
This allowed, in 1937, to have a more powerful armament.

TGB500C, Byzantine Empire TGB Coastal class laid down 1937

Displacement:
   500 t light; 548 t standard; 585 t normal; 614 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (245,18 ft / 242,78 ft) x 26,25 ft x (8,03 / 8,29 ft)
   (74,73 m / 74,00 m) x 8,00 m  x (2,45 / 2,53 m)

Armament:
      4 - 4,02" / 102 mm 45,0 cal guns - 33,00lbs / 14,97kg shells, 250 per gun
     Dual purpose guns in deck mounts, 1937 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
     Anti-air guns in deck mounts, 1937 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      2 raised mounts
      4 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
     Quick firing guns in deck mounts, 1937 Model
     2 x 2-gun mounts on sides, forward deck aft
      2 raised mounts
      4 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 4 000 per gun
     Machine guns in deck mounts, 1937 Model
     2 x 2-gun mounts on sides, forward deck forward
      2 raised mounts
      Weight of broadside 148 lbs / 67 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,39" / 10 mm         -               -
   2nd:   0,39" / 10 mm         -               -
   3rd:   0,39" / 10 mm         -               -
   4th:   0,24" / 6 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 7 640 shp / 5 699 Kw = 25,10 kts
   Range 4 000nm at 10,00 kts
   Bunker at max displacement = 65 tons

Complement:
   59 - 77

Cost:
   £0,297 million / $1,186 million

Distribution of weights at normal displacement:
   Armament: 29 tons, 4,9 %
      - Guns: 29 tons, 4,9 %
   Armour: 6 tons, 0,9 %
      - Armament: 6 tons, 0,9 %
   Machinery: 212 tons, 36,2 %
   Hull, fittings & equipment: 207 tons, 35,4 %
   Fuel, ammunition & stores: 85 tons, 14,5 %
   Miscellaneous weights: 47 tons, 8,0 %
      - On freeboard deck: 44 tons
      - Above deck: 3 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     395 lbs / 179 Kg = 12,2 x 4,0 " / 102 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,15
   Metacentric height 0,9 ft / 0,3 m
   Roll period: 11,8 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0,38
   Seaboat quality  (Average = 1.00): 1,31

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0,400 / 0,407
   Length to Beam Ratio: 9,25 : 1
   'Natural speed' for length: 15,58 kts
   Power going to wave formation at top speed: 62 %
   Trim (Max stability = 0, Max steadiness = 100): 54
   Bow angle (Positive = bow angles forward): 8,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   18,00 %,  17,06 ft / 5,20 m,  13,29 ft / 4,05 m
      - Forward deck:   33,00 %,  13,29 ft / 4,05 m,  10,01 ft / 3,05 m
      - Aft deck:   33,00 %,  10,01 ft / 3,05 m,  9,35 ft / 2,85 m
      - Quarter deck:   16,00 %,  9,35 ft / 2,85 m,  9,35 ft / 2,85 m
      - Average freeboard:      11,20 ft / 3,41 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 134,4 %
      - Above water (accommodation/working, high = better): 135,0 %
   Waterplane Area: 3 922 Square feet or 364 Square metres
   Displacement factor (Displacement / loading): 107 %
   Structure weight / hull surface area: 30 lbs/sq ft or 148 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,65
      - Longitudinal: 2,78
      - Overall: 0,75
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

AD
Short range Marconi
3t for top fire control
OD
9t for 1x3TTx533t
15t for enhanced Hydrophone
6t for 60 x91kg DC
4t for night fighting
2t for Y DC
8t reserved
AW
climatisation

2440nm@15kts
1200nm@20kts
640nm@25kts

D18, Byzantine Empire Fleet  Destroyer laid down 1937

Displacement:
   1 500 t light; 1 615 t standard; 1 881 t normal; 2 093 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (364,15 ft / 360,89 ft) x 35,04 ft x (12,70 / 13,65 ft)
   (110,99 m / 110,00 m) x 10,68 m  x (3,87 / 4,16 m)

Armament:
      4 - 4,49" / 114 mm 45,0 cal guns - 58,00lbs / 26,31kg shells, 320 per gun
     Dual purpose guns in deck mounts, 1937 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      8 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
     Anti-air guns in deck mounts, 1937 Model
     2 x 4-gun mounts on centreline ends, evenly spread
      2 raised mounts
      8 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
     Anti-air guns in deck mounts, 1937 Model
     2 x 4-gun mounts on sides, forward deck aft
      2 raised mounts
      4 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 4 000 per gun
     Machine guns in deck mounts, 1937 Model
     2 x 2-gun mounts on sides, forward deck forward
      2 raised mounts
      Weight of broadside 264 lbs / 120 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   0,39" / 10 mm         -               -
   2nd:   0,24" / 6 mm         -               -
   3rd:   0,24" / 6 mm         -               -
   4th:   0,24" / 6 mm         -               -

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 38 620 shp / 28 811 Kw = 32,62 kts
   Range 10 000nm at 12,00 kts
   Bunker at max displacement = 478 tons

Complement:
   142 - 185

Cost:
   £1,062 million / $4,247 million

Distribution of weights at normal displacement:
   Armament: 41 tons, 2,2 %
      - Guns: 41 tons, 2,2 %
   Armour: 4 tons, 0,2 %
      - Armament: 4 tons, 0,2 %
   Machinery: 940 tons, 50,0 %
   Hull, fittings & equipment: 444 tons, 23,6 %
   Fuel, ammunition & stores: 381 tons, 20,2 %
   Miscellaneous weights: 70 tons, 3,7 %
      - On freeboard deck: 66 tons
      - Above deck: 4 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     533 lbs / 242 Kg = 11,8 x 4,5 " / 114 mm shells or 0,3 torpedoes
   Stability (Unstable if below 1.00): 1,31
   Metacentric height 1,7 ft / 0,5 m
   Roll period: 11,3 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0,21
   Seaboat quality  (Average = 1.00): 1,03

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0,410 / 0,425
   Length to Beam Ratio: 10,30 : 1
   'Natural speed' for length: 19,00 kts
   Power going to wave formation at top speed: 65 %
   Trim (Max stability = 0, Max steadiness = 100): 69
   Bow angle (Positive = bow angles forward): 9,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   17,50 %,  20,59 ft / 6,28 m,  15,99 ft / 4,88 m
      - Forward deck:   33,50 %,  15,99 ft / 4,88 m,  12,71 ft / 3,88 m
      - Aft deck:   33,50 %,  12,71 ft / 3,88 m,  12,55 ft / 3,83 m
      - Quarter deck:   15,50 %,  12,55 ft / 3,83 m,  12,55 ft / 3,83 m
      - Average freeboard:      14,11 ft / 4,30 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 170,6 %
      - Above water (accommodation/working, high = better): 141,7 %
   Waterplane Area: 7 831 Square feet or 728 Square metres
   Displacement factor (Displacement / loading): 81 %
   Structure weight / hull surface area: 32 lbs/sq ft or 156 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,50
      - Longitudinal: 1,45
      - Overall: 0,55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

AD
4t for top fire control
Short Marconi
OD
24t for 2x3TTx533 HW
15t for enhanced hydrophone
5t for night fighting
6t for 30x195kg DC
2t for Y DC
2t for paravanes
12t reserved
AW
Climatisation

Trial speed: 33kts
Bonus: 0.39

6100nm-15kts
3000nm-20kts
1600nm-25kts
1000nm-30kts

I don't care for the minimal stability on the AGB7000. We do not really have a standard, but 1.03 means there is little counterflooding ability, and generally I like 1.10 as a baseline. Ironically I was working on a gunboat very similar to it, but wasn't even thinking of that level of speed.  The bow is also 2.64m higher than where the guns are, so over a full deck level.  Granted for any long range fire, they would elevate the guns, but I should mention it.

The D18 reminds me of my Robah 1932 class Fleet Destroyers, but slightly larger and understandably faster. Nice ASW outfit.

Like the Parthians, Byzantium must replace these old colonial battleships.
The basic choice fell on the BB25 class, "Kalin"
LD 1916 - 15300t - 24kts - 2T3x343 reworked for the colonies.

Byzantine Empire Colonial BB laid down 1937

Displacement:
   13 150 t light; 14 111 t standard; 14 704 t normal; 15 179 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (489,85 ft / 485,56 ft) x 80,91 ft x (22,02 / 22,60 ft)
   (149,30 m / 148,00 m) x 24,66 m  x (6,71 / 6,89 m)

Armament:
      6 - 13,50" / 343 mm 45,0 cal guns - 1 410,01lbs / 639,57kg shells, 100 per gun
     Breech loading guns in turret on barbette mounts, 1937 Model
     2 x 3-gun mounts on centreline ends, evenly spread
      4 - 4,49" / 114 mm 45,0 cal guns - 58,00lbs / 26,31kg shells, 320 per gun
     Dual purpose guns in deck mounts, 1937 Model
     2 x 2-gun mounts on centreline ends, evenly spread
      2 raised mounts
      8 - 4,49" / 114 mm 45,0 cal guns - 58,00lbs / 26,31kg shells, 320 per gun
     Dual purpose guns in deck mounts, 1937 Model
     4 x 2-gun mounts on sides, evenly spread
      32 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
     Quick firing guns in deck mounts, 1937 Model
     8 x 4-gun mounts on sides, evenly spread
      8 raised mounts
      16 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 4 000 per gun
     Machine guns in deck mounts, 1937 Model
     8 x 2-gun mounts on side ends, evenly spread
      8 raised mounts
      Weight of broadside 9 221 lbs / 4 183 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   9,06" / 230 mm   315,62 ft / 96,20 m   11,15 ft / 3,40 m
   Ends:   1,57" / 40 mm   169,91 ft / 51,79 m   9,84 ft / 3,00 m
   Upper:   1,57" / 40 mm   315,62 ft / 96,20 m   8,01 ft / 2,44 m
     Main Belt covers 100 % of normal length

   - Torpedo Bulkhead - Strengthened structural bulkheads:
      1,77" / 45 mm   315,62 ft / 96,20 m   20,73 ft / 6,32 m
   Beam between torpedo bulkheads 64,50 ft / 19,66 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   11,8" / 300 mm   3,94" / 100 mm      9,84" / 250 mm
   2nd:   0,39" / 10 mm         -               -
   3rd:   0,39" / 10 mm         -               -
   4th:   0,24" / 6 mm         -               -
   5th:   0,24" / 6 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 3,94" / 100 mm
   Forecastle: 1,57" / 40 mm  Quarter deck: 2,76" / 70 mm

   - Conning towers: Forward 11,81" / 300 mm, Aft 3,94" / 100 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 34 560 shp / 25 782 Kw = 23,00 kts
   Range 6 000nm at 12,00 kts
   Bunker at max displacement = 1 068 tons

Complement:
   666 - 867

Cost:
   £7,196 million / $28,782 million

Distribution of weights at normal displacement:
   Armament: 1 686 tons, 11,5 %
      - Guns: 1 686 tons, 11,5 %
   Armour: 5 115 tons, 34,8 %
      - Belts: 1 680 tons, 11,4 %
      - Torpedo bulkhead: 429 tons, 2,9 %
      - Armament: 871 tons, 5,9 %
      - Armour Deck: 1 932 tons, 13,1 %
      - Conning Towers: 204 tons, 1,4 %
   Machinery: 958 tons, 6,5 %
   Hull, fittings & equipment: 5 025 tons, 34,2 %
   Fuel, ammunition & stores: 1 555 tons, 10,6 %
   Miscellaneous weights: 365 tons, 2,5 %
      - Hull below water: 66 tons
      - On freeboard deck: 106 tons
      - Above deck: 193 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     22 132 lbs / 10 039 Kg = 18,0 x 13,5 " / 343 mm shells or 4,3 torpedoes
   Stability (Unstable if below 1.00): 1,17
   Metacentric height 4,9 ft / 1,5 m
   Roll period: 15,4 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0,71
   Seaboat quality  (Average = 1.00): 1,15

Hull form characteristics:
   Hull has a flush deck,
     a ram bow and a cruiser stern
   Block coefficient (normal/deep): 0,595 / 0,598
   Length to Beam Ratio: 6,00 : 1
   'Natural speed' for length: 22,04 kts
   Power going to wave formation at top speed: 53 %
   Trim (Max stability = 0, Max steadiness = 100): 62
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   18,00 %,  24,28 ft / 7,40 m,  19,52 ft / 5,95 m
      - Forward deck:   32,50 %,  19,52 ft / 5,95 m,  15,42 ft / 4,70 m
      - Aft deck:   32,50 %,  15,42 ft / 4,70 m,  15,09 ft / 4,60 m
      - Quarter deck:   17,00 %,  15,09 ft / 4,60 m,  15,09 ft / 4,60 m
      - Average freeboard:      17,06 ft / 5,20 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 85,5 %
      - Above water (accommodation/working, high = better): 133,8 %
   Waterplane Area: 28 598 Square feet or 2 657 Square metres
   Displacement factor (Displacement / loading): 103 %
   Structure weight / hull surface area: 162 lbs/sq ft or 792 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,92
      - Longitudinal: 1,94
      - Overall: 1,00
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

AD
168t fire control - 1930
25t Marconi
20t for Hulsmeyer
OD
24t for 2x3TTx533HW
15t for enhanced Hydrophone
20t for night fighting
25t for cata + seaplane
22t reserved
AW
climatisation
BW
66t for extra pump installation

...& a lighter class with 2T3x305

Byzantine Empire Light Colonial BB laid down 1937

Displacement:
   10 300 t light; 11 007 t standard; 11 508 t normal; 11 910 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (491,48 ft / 487,20 ft) x 75,46 ft x (21,38 / 21,95 ft)
   (149,80 m / 148,50 m) x 23,00 m  x (6,52 / 6,69 m)

Armament:
      6 - 12,01" / 305 mm 51,0 cal guns - 920,61lbs / 417,58kg shells, 100 per gun
     Breech loading guns in turret on barbette mounts, 1937 Model
     2 x 3-gun mounts on centreline ends, evenly spread
      12 - 4,49" / 114 mm 45,0 cal guns - 58,00lbs / 26,31kg shells, 340 per gun
     Dual purpose guns in deck mounts, 1937 Model
     6 x 2-gun mounts on sides, evenly spread
      16 - 1,57" / 40,0 mm 39,0 cal guns - 2,01lbs / 0,91kg shells, 2 000 per gun
     Anti-air guns in deck mounts, 1937 Model
     8 x 2-gun mounts on side ends, evenly spread
      8 raised mounts
      16 - 0,50" / 12,7 mm 62,0 cal guns - 0,07lbs / 0,03kg shells, 4 000 per gun
     Machine guns in deck mounts, 1937 Model
     8 x 2-gun mounts on side ends, evenly spread
      8 raised mounts
      Weight of broadside 6 253 lbs / 2 836 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   7,87" / 200 mm   331,30 ft / 100,98 m   10,66 ft / 3,25 m
   Ends:   1,18" / 30 mm   155,87 ft / 47,51 m   9,84 ft / 3,00 m
     Main Belt covers 105 % of normal length

   - Torpedo Bulkhead - Strengthened structural bulkheads:
      1,77" / 45 mm   331,30 ft / 100,98 m   19,06 ft / 5,81 m
   Beam between torpedo bulkheads 55,77 ft / 17,00 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   10,2" / 260 mm   2,36" / 60 mm      7,87" / 200 mm
   3rd:   0,39" / 10 mm         -               -
   4th:   0,24" / 6 mm         -               -
   5th:   0,24" / 6 mm         -               -

   - Protected deck - single deck:
   For and Aft decks: 2,56" / 65 mm
   Forecastle: 1,18" / 30 mm  Quarter deck: 1,97" / 50 mm

   - Conning towers: Forward 7,87" / 200 mm, Aft 3,94" / 100 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 33 512 shp / 25 000 Kw = 24,00 kts
   Range 6 000nm at 12,00 kts
   Bunker at max displacement = 903 tons

Complement:
   555 - 722

Cost:
   £6,017 million / $24,069 million

Distribution of weights at normal displacement:
   Armament: 1 479 tons, 12,8 %
      - Guns: 1 479 tons, 12,8 %
   Armour: 3 488 tons, 30,3 %
      - Belts: 1 258 tons, 10,9 %
      - Torpedo bulkhead: 414 tons, 3,6 %
      - Armament: 573 tons, 5,0 %
      - Armour Deck: 1 113 tons, 9,7 %
      - Conning Towers: 130 tons, 1,1 %
   Machinery: 929 tons, 8,1 %
   Hull, fittings & equipment: 3 953 tons, 34,3 %
   Fuel, ammunition & stores: 1 208 tons, 10,5 %
   Miscellaneous weights: 452 tons, 3,9 %
      - Hull below water: 55 tons
      - Hull above water: 75 tons
      - On freeboard deck: 129 tons
      - Above deck: 193 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     16 220 lbs / 7 357 Kg = 18,7 x 12,0 " / 305 mm shells or 3,2 torpedoes
   Stability (Unstable if below 1.00): 1,16
   Metacentric height 4,3 ft / 1,3 m
   Roll period: 15,3 seconds
   Steadiness   - As gun platform (Average = 50 %): 71 %
         - Recoil effect (Restricted arc if above 1.00): 0,65
   Seaboat quality  (Average = 1.00): 1,22

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0,513 / 0,517
   Length to Beam Ratio: 6,46 : 1
   'Natural speed' for length: 22,07 kts
   Power going to wave formation at top speed: 52 %
   Trim (Max stability = 0, Max steadiness = 100): 58
   Bow angle (Positive = bow angles forward): 10,00 degrees
   Stern overhang: 0,00 ft / 0,00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   16,50 %,  24,25 ft / 7,39 m,  19,82 ft / 6,04 m
      - Forward deck:   34,00 %,  19,82 ft / 6,04 m,  15,42 ft / 4,70 m
      - Aft deck:   34,00 %,  15,42 ft / 4,70 m,  15,42 ft / 4,70 m
      - Quarter deck:   15,50 %,  15,42 ft / 4,70 m,  15,42 ft / 4,70 m
      - Average freeboard:      17,19 ft / 5,24 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 103,7 %
      - Above water (accommodation/working, high = better): 140,5 %
   Waterplane Area: 24 777 Square feet or 2 302 Square metres
   Displacement factor (Displacement / loading): 99 %
   Structure weight / hull surface area: 147 lbs/sq ft or 717 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0,93
      - Longitudinal: 1,91
      - Overall: 1,00
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Good seaboat, rides out heavy weather easily

AD
25t for Long Range Marconi
148t for top mast rangefinder - 1930
20t for Hulsmeyer
OD
24t for 2x3TTx21"HW
20t for night fighting
15t for enhanced hydrophone
50t for 2 armed seaplanes + cata
20t reserved
AW
climatisation
BW
55t for additionnal pumps

Quote from: Jefgte on February 23, 2025, 11:42:37 AMLike the Parthians, Byzantium must replace these old colonial battleships.
The basic choice fell on the BB25 class, "Kalin"
LD 1916 - 15300t - 24kts - 2T3x343 reworked for the colonies.

Byzantine Empire Colonial BB laid down 1937

That seems substantially better than my Drubust for minimal 'cost'.
It may be worth my while to recreate it and see if I can learn something to improve my design.
The 6 vs 8 guns is an obvious difference...but.
The Frawar was even better, but cost even more.

QuoteThat seems substantially better than my Drubust for minimal 'cost'.
It may be worth my while to recreate it and see if I can learn something to improve my design.
The 6 vs 8 guns is an obvious difference.
The Frawar was even better, but cost even more....but.

Minimum cost is essential.
Fleets are in a supported program with 45000t BBs, 25-27000t CVs with the neccessary accompanying ships, very greedy in BPs.
They must represent a very powerful and dissuasive strike force against any aggression.
 
Colonial ships must be numerous and economical, not very greedy in BPs.

Panzerschiff style seems excellent to me for colonies.

Budget will decide the choice:
13150t - 2T3x343 or 10300t - 2T3x305