Aztec Ship Designs 1925-1928

[Kaiser Kirk]

Always satisfying when you take a design that is not quite there...and unlock making it what you want :)

[TacCovert4]

Yeah, I'll probably pull the hydrophones,  and justify down the flag facilities.   Taking a bit of inspiration from your own stuff.  Add 5t to the bridge for some seating and maybe an extra table, 15t for a plotting room by the cic,  and 10t for the rear admiral and 3 staff.

[TacCovert4]

A somewhat different idea......using a DD for bringing armed catapult aircraft to the fleet.

I-Class, Aztec Destroyer laid down 1925

Displacement:
   2,000 t light; 2,082 t standard; 2,329 t normal; 2,528 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (400.27 ft / 393.70 ft) x 36.09 ft x (10.43 / 11.13 ft)
   (122.00 m / 120.00 m) x 11.00 m  x (3.18 / 3.39 m)

Armament:
      4 - 5.12" / 130 mm 50.0 cal guns - 70.97lbs / 32.19kg shells, 200 per gun
     Quick firing guns in deck and hoist mounts, 1925 Model
     3 x Twin mounts on centreline, forward evenly spread
      1 raised mount
      8 - 1.18" / 30.0 mm 50.0 cal guns - 0.86lbs / 0.39kg shells, 1,000 per gun
     Quick firing guns in deck and hoist mounts, 1925 Model
     4 x Twin mounts on sides, evenly spread
      Weight of broadside 291 lbs / 132 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.18" / 30 mm   1.18" / 30 mm      1.18" / 30 mm
   2nd:         -            -         1.18" / 30 mm

   - Conning towers: Forward 1.18" / 30 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 43,429 shp / 32,398 Kw = 32.25 kts
   Range 5,000nm at 14.00 kts
   Bunker at max displacement = 446 tons

Complement:
   166 - 217

Cost:
   £0.872 million / $3.489 million

Distribution of weights at normal displacement:
   Armament: 71 tons, 3.0 %
      - Guns: 71 tons, 3.0 %
   Armour: 30 tons, 1.3 %
      - Armament: 26 tons, 1.1 %
      - Conning Tower: 4 tons, 0.2 %
   Machinery: 1,181 tons, 50.7 %
   Hull, fittings & equipment: 619 tons, 26.6 %
   Fuel, ammunition & stores: 330 tons, 14.2 %
   Miscellaneous weights: 98 tons, 4.2 %
      - Hull below water: 5 tons
      - On freeboard deck: 86 tons
      - Above deck: 7 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     673 lbs / 305 Kg = 10.0 x 5.1 " / 130 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 1.5 ft / 0.5 m
   Roll period: 12.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 60 %
         - Recoil effect (Restricted arc if above 1.00): 0.53
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has low quarterdeck ,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.550 / 0.559
   Length to Beam Ratio: 10.91 : 1
   'Natural speed' for length: 19.84 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 60
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  18.04 ft / 5.50 m,  16.73 ft / 5.10 m
      - Forward deck:   30.00 %,  16.73 ft / 5.10 m,  16.40 ft / 5.00 m
      - Aft deck:   35.00 %,  16.40 ft / 5.00 m,  16.40 ft / 5.00 m
      - Quarter deck:   15.00 %,  9.84 ft / 3.00 m,  9.84 ft / 3.00 m
      - Average freeboard:      15.64 ft / 4.77 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 176.7 %
      - Above water (accommodation/working, high = better): 187.5 %
   Waterplane Area: 9,916 Square feet or 921 Square metres
   Displacement factor (Displacement / loading): 72 %
   Structure weight / hull surface area: 36 lbs/sq ft or 175 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.33
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

7t - 1918 FC
16t - 2x2x21in HW TT Sides Amidships
60t - 2 x Catapults and Armed Floatplanes Aft
5t - Hydrophones
4t - DC Thrower x 4
6t - DCs for the Throwers

[TacCovert4]

And a somewhat different DD Concept, going back to the All-rounder type that the H-class was, taking the base F-class hull, and modernizing it.  Downside, the guns don't have independent hoists.  Upside, under 1600t for full-spectrum capabilities.  Ignore the beam between bulkheads warning, there's no armor there so it's irrelevant and I'll fix it in the final tweak.

DD-F, Aztec Destroyer laid down 1926

Displacement:
    1,546 t light; 1,628 t standard; 1,882 t normal; 2,085 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
    (365.73 ft / 360.89 ft) x 31.17 ft x (11.48 / 12.47 ft)
    (111.47 m / 110.00 m) x 9.50 m  x (3.50 / 3.80 m)

Armament:
      5 - 5.12" / 130 mm 50.0 cal guns - 70.97lbs / 32.19kg shells, 200 per gun
      Quick firing guns in deck mounts, 1926 Model
      5 x Single mounts on centreline ends, majority forward
        2 raised mounts - superfiring
      12 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.40kg shells, 1,000 per gun
      Anti-air guns in deck and hoist mounts, 1926 Model
      6 x Single mounts on centreline, aft deck forward
      Weight of broadside 365 lbs / 166 kg

Armour:
   - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    1.06" / 27 mm    1.06" / 27 mm              -
    2nd:          -              -            0.98" / 25 mm

   - Conning towers: Forward 1.06" / 27 mm, Aft 0.00" / 0 mm

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 2 shafts, 37,103 shp / 27,679 Kw = 32.00 kts
    Range 6,000nm at 14.00 kts
    Bunker at max displacement = 457 tons

Complement:
    142 - 185

Cost:
    £0.720 million / $2.880 million

Distribution of weights at normal displacement:
    Armament: 74 tons, 3.9 %
       - Guns: 74 tons, 3.9 %
    Armour: 40 tons, 2.1 %
       - Armament: 37 tons, 1.9 %
       - Conning Tower: 3 tons, 0.2 %
    Machinery: 955 tons, 50.8 %
    Hull, fittings & equipment: 419 tons, 22.3 %
    Fuel, ammunition & stores: 337 tons, 17.9 %
    Miscellaneous weights: 57 tons, 3.0 %
       - Hull below water: 15 tons
       - On freeboard deck: 34 tons
       - Above deck: 8 tons

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      475 lbs / 215 Kg = 7.1 x 5.1 " / 130 mm shells or 0.3 torpedoes
    Stability (Unstable if below 1.00): 1.21
    Metacentric height 1.2 ft / 0.4 m
    Roll period: 11.8 seconds
    Steadiness    - As gun platform (Average = 50 %): 70 %
            - Recoil effect (Restricted arc if above 1.00): 0.51
    Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
    Hull has rise forward of midbreak,
      a normal bow and a cruiser stern
    Block coefficient (normal/deep): 0.510 / 0.520
    Length to Beam Ratio: 11.58 : 1
    'Natural speed' for length: 19.00 kts
    Power going to wave formation at top speed: 66 %
    Trim (Max stability = 0, Max steadiness = 100): 69
    Bow angle (Positive = bow angles forward): 15.00 degrees
    Stern overhang: 0.00 ft / 0.00 m
    Freeboard (% = length of deck as a percentage of waterline length):
                Fore end,     Aft end
       - Forecastle:    20.00 %,  18.04 ft / 5.50 m,  18.04 ft / 5.50 m
       - Forward deck:    30.00 %,  18.04 ft / 5.50 m,  18.04 ft / 5.50 m
       - Aft deck:    35.00 %,  9.84 ft / 3.00 m,  9.84 ft / 3.00 m
       - Quarter deck:    15.00 %,  9.84 ft / 3.00 m,  9.84 ft / 3.00 m
       - Average freeboard:        13.94 ft / 4.25 m
    Ship tends to be wet forward

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 176.4 %
        - Above water (accommodation/working, high = better): 138.3 %
    Waterplane Area: 7,563 Square feet or 703 Square metres
    Displacement factor (Displacement / loading): 71 %
    Structure weight / hull surface area: 31 lbs/sq ft or 151 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0.50
        - Longitudinal: 1.44
        - Overall: 0.56
    Cramped machinery, storage, compartmentation space
    Excellent accommodation and workspace room
    Ship has slow, easy roll, a good, steady gun platform

Warning: Beam between bulkheads too wide

15t -Advanced  Hydrophones
14t - Depth Charges
4t - 4 x DC Thrower
16t - 1 x 4 x 21in HW TT Centerline
8t - 1918 FC

[TacCovert4]

Considering the needs for minesweeping/maintenance, as well as the need for more coastal/convoy patrol and ASW.  Plus, the MS-1 mine-warfare ships are 20 years old now, running on coal-fired reciprocating engines.  The new ships will have modern diesels, trans-oceanic range, and electric motors to make them even more maneuverable.

Flower Mk2, Aztec ASW-Minesweeper laid down 1926

Displacement:
   476 t light; 497 t standard; 581 t normal; 648 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (196.85 ft / 196.85 ft) x 26.25 ft x (6.56 / 7.18 ft)
   (60.00 m / 60.00 m) x 8.00 m  x (2.00 / 2.19 m)

Armament:
      2 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 150 per gun
     Quick firing guns in deck mounts, 1926 Model
     2 x Single mounts on centreline ends, evenly spread
      1 raised mount - superfiring
      8 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.40kg shells, 1,000 per gun
     Anti-air guns in deck mounts, 1926 Model
     8 x Single mounts on sides, evenly spread
      Weight of broadside 72 lbs / 32 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.18" / 30 mm         -               -
   2nd:   1.18" / 30 mm         -               -

   - Conning towers: Forward 1.18" / 30 mm, Aft 0.00" / 0 mm

Machinery:
   Diesel Internal combustion generators,
   Electric motors, 2 shafts, 3,834 shp / 2,860 Kw = 20.00 kts
   Range 3,500nm at 14.00 kts
   Bunker at max displacement = 151 tons

Complement:
   58 - 76

Cost:
   £0.131 million / $0.524 million

Distribution of weights at normal displacement:
   Armament: 15 tons, 2.6 %
      - Guns: 15 tons, 2.6 %
   Armour: 16 tons, 2.8 %
      - Armament: 14 tons, 2.5 %
      - Conning Tower: 2 tons, 0.3 %
   Machinery: 123 tons, 21.1 %
   Hull, fittings & equipment: 153 tons, 26.3 %
   Fuel, ammunition & stores: 105 tons, 18.1 %
   Miscellaneous weights: 169 tons, 29.1 %
      - Hull below water: 92 tons
      - On freeboard deck: 50 tons
      - Above deck: 27 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     743 lbs / 337 Kg = 24.4 x 3.9 " / 100 mm shells or 0.5 torpedoes
   Stability (Unstable if below 1.00): 1.28
   Metacentric height 1.1 ft / 0.3 m
   Roll period: 10.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 60 %
         - Recoil effect (Restricted arc if above 1.00): 0.15
   Seaboat quality  (Average = 1.00): 1.02

Hull form characteristics:
   Hull has rise forward of midbreak,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.600 / 0.611
   Length to Beam Ratio: 7.50 : 1
   'Natural speed' for length: 14.03 kts
   Power going to wave formation at top speed: 64 %
   Trim (Max stability = 0, Max steadiness = 100): 59
   Bow angle (Positive = bow angles forward): 0.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  13.12 ft / 4.00 m,  13.12 ft / 4.00 m
      - Forward deck:   30.00 %,  13.12 ft / 4.00 m,  13.12 ft / 4.00 m
      - Aft deck:   35.00 %,  6.56 ft / 2.00 m,  6.56 ft / 2.00 m
      - Quarter deck:   15.00 %,  6.56 ft / 2.00 m,  6.56 ft / 2.00 m
      - Average freeboard:      9.84 ft / 3.00 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 93.8 %
      - Above water (accommodation/working, high = better): 119.0 %
   Waterplane Area: 3,779 Square feet or 351 Square metres
   Displacement factor (Displacement / loading): 124 %
   Structure weight / hull surface area: 27 lbs/sq ft or 133 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.69
      - Longitudinal: 1.89
      - Overall: 0.76
   Caution: Hull subject to strain in open-sea
   Adequate machinery, storage, compartmentation space
   Adequate accommodation and workspace room

Warning: Beam between bulkheads too wide

-Aft Gun Mount on Pedestal Above Deck Level-

AD
2t - 1918 FC
25t - LR Radio

OD
2t - 2 x DC Thrower
8t - 40 x DC
20t - Space for20 Mines for local minefield maintenance, or 100 DC
20t - Minesweeping Equipment

BW-----
15t - Advanced Hydrophone Package
37t - Diesel Engines
40t - Electric Drives
*7044nm Range at Cruise*

[Kaiser Kirk]

  Downside, the guns don't have independent hoists.  Upside, under 1600t for full-spectrum capabilities.  Ignore the beam between bulkheads warning, there's no armor there so it's irrelevant and I'll fix it in the final tweak.

Destroyers in this period generally didn't have hoists.
Under Ship Design Snip specifically calls that out for WW1 DDs, but we are moving into Interwar.
Compared to a cruiser, they probably had less deck levels to haul the ammo up as well.

Not sure I understand "full spectrum under 1600t"....
I presume you have the 1918 DD tech, so can reach 2000t and are just pleased to craft a full function DD that does not cost that much?

The stupid beam warning we all get if we forget to change it to 0.

As for Minewarefare / ASW,  I started with Mil-spec minesweepers,
but have gone with multi-role aux-build sloops more recently.
I will likely make some 'fleet' mil-spec MS later.

As for the preceeding Catapult equipped DD, the Dutch actually fielded some Aircraft-hosting Destroyers.

[TacCovert4]

  Downside, the guns don't have independent hoists.  Upside, under 1600t for full-spectrum capabilities.  Ignore the beam between bulkheads warning, there's no armor there so it's irrelevant and I'll fix it in the final tweak.

Destroyers in this period generally didn't have hoists.
Under Ship Design Snip specifically calls that out for WW1 DDs, but we are moving into Interwar.
Compared to a cruiser, they probably had less deck levels to haul the ammo up as well.

Not sure I understand "full spectrum under 1600t"....
I presume you have the 1918 DD tech, so can reach 2000t and are just pleased to craft a full function DD that does not cost that much?

The stupid beam warning we all get if we forget to change it to 0.

As for Minewarefare / ASW,  I started with Mil-spec minesweepers,
but have gone with multi-role aux-build sloops more recently.
I will likely make some 'fleet' mil-spec MS later.

As for the preceeding Catapult equipped DD, the Dutch actually fielded some Aircraft-hosting Destroyers.

Yeah,  the Dutch were my inspiration there.  I'm not seeing the sultanate as able to field the carrier numbers.  So a sort of Japanese esque protocol of aircraft on everything is going to be a mode.

The idea of a full spectrum dd is to have all capabilities on one hull that is reasonably good at all of them.  I've proven able to build a monster fleet dd at 2000t.  But it's expensive and the 1600t option has the general capabilities I need on the budget I also need with so many requirements.

[The Rock Doctor]

Was not aware of the Dutch aircraft-carrying destroyers and must now seek them out.

[TacCovert4]

It came to my attention that in Terra Del Fuego there is only the 1 Penguin-class Ice-rated cruiser (and barely a cruiser at that).  Remembering the needs of that somewhat unique colony, I once again turn my attention to a ship completely different in many respects from the ones I design for the bulk of the fleet.  That being amazing seakeeping, weather performance, and a mix of traditional cruiser and life-saving equipment.

Sea Lion, Aztec Icebreaker Cruiser laid down 1926

Displacement:
   3,612 t light; 3,754 t standard; 4,103 t normal; 4,383 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (399.41 ft / 387.14 ft) x 45.96 ft x (13.45 / 14.20 ft)
   (121.74 m / 118.00 m) x 14.01 m  x (4.10 / 4.33 m)

Armament:
      6 - 5.12" / 130 mm 50.0 cal guns - 70.97lbs / 32.19kg shells, 200 per gun
     Quick firing guns in deck and hoist mounts, 1926 Model
     3 x Single mounts on centreline ends, majority forward
      1 raised mount - superfiring
      4 - 2.76" / 70.0 mm 50.0 cal guns - 11.08lbs / 5.03kg shells, 300 per gun
     Anti-air guns in deck mounts, 1926 Model
     4 x Twin mounts on sides, evenly spread
      8 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.40kg shells, 1,000 per gun
     Anti-air guns in deck and hoist mounts, 1926 Model
     4 x Twin mounts on side ends, evenly spread
      12 - 0.47" / 12.0 mm 70.0 cal guns - 0.06lbs / 0.03kg shells, 2,000 per gun
     Machine guns in deck mount, 1926 Model
     1 x Single mount on sides amidships
      Weight of broadside 478 lbs / 217 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   1.97" / 50 mm   251.64 ft / 76.70 m   9.84 ft / 3.00 m
   Ends:   1.57" / 40 mm   135.47 ft / 41.29 m   9.84 ft / 3.00 m
     Main Belt covers 100 % of normal length
     Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead - Additional damage containing bulkheads:
      1.18" / 30 mm   251.64 ft / 76.70 m   12.70 ft / 3.87 m
   Beam between torpedo bulkheads 32.81 ft / 10.00 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   2.36" / 60 mm   1.57" / 40 mm      2.36" / 60 mm
   2nd:   0.79" / 20 mm   0.79" / 20 mm            -
   3rd:   0.79" / 20 mm   0.79" / 20 mm      0.79" / 20 mm
   4th:   0.47" / 12 mm   0.47" / 12 mm            -

   - Armoured deck - single deck:
   For and Aft decks: 1.38" / 35 mm
   Forecastle: 0.98" / 25 mm  Quarter deck: 0.98" / 25 mm

   - Conning towers: Forward 2.36" / 60 mm, Aft 0.00" / 0 mm

Machinery:
   Diesel Internal combustion motors,
   Geared drive, 2 shafts, 23,058 shp / 17,201 Kw = 25.00 kts
   Range 5,000nm at 14.00 kts
   Bunker at max displacement = 629 tons

Complement:
   256 - 333

Cost:
   £0.963 million / $3.853 million

Distribution of weights at normal displacement:
   Armament: 139 tons, 3.4 %
      - Guns: 139 tons, 3.4 %
   Armour: 834 tons, 20.3 %
      - Belts: 283 tons, 6.9 %
      - Torpedo bulkhead: 140 tons, 3.4 %
      - Armament: 82 tons, 2.0 %
      - Armour Deck: 317 tons, 7.7 %
      - Conning Tower: 13 tons, 0.3 %
   Machinery: 738 tons, 18.0 %
   Hull, fittings & equipment: 1,480 tons, 36.1 %
   Fuel, ammunition & stores: 491 tons, 12.0 %
   Miscellaneous weights: 421 tons, 10.3 %
      - Hull below water: 227 tons
      - Hull above water: 60 tons
      - On freeboard deck: 70 tons
      - Above deck: 64 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     7,644 lbs / 3,467 Kg = 114.0 x 5.1 " / 130 mm shells or 1.7 torpedoes
   Stability (Unstable if below 1.00): 1.20
   Metacentric height 2.2 ft / 0.7 m
   Roll period: 13.0 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.33
   Seaboat quality  (Average = 1.00): 1.53

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.600 / 0.607
   Length to Beam Ratio: 8.42 : 1
   'Natural speed' for length: 19.68 kts
   Power going to wave formation at top speed: 58 %
   Trim (Max stability = 0, Max steadiness = 100): 46
   Bow angle (Positive = bow angles forward): 15.00 degrees
   Stern overhang: 6.56 ft / 2.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   20.00 %,  21.33 ft / 6.50 m,  19.69 ft / 6.00 m
      - Forward deck:   30.00 %,  19.69 ft / 6.00 m,  18.04 ft / 5.50 m
      - Aft deck:   35.00 %,  18.04 ft / 5.50 m,  18.04 ft / 5.50 m
      - Quarter deck:   15.00 %,  18.04 ft / 5.50 m,  18.04 ft / 5.50 m
      - Average freeboard:      18.75 ft / 5.72 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 109.6 %
      - Above water (accommodation/working, high = better): 178.4 %
   Waterplane Area: 13,015 Square feet or 1,209 Square metres
   Displacement factor (Displacement / loading): 128 %
   Structure weight / hull surface area: 70 lbs/sq ft or 339 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.90
      - Longitudinal: 2.53
      - Overall: 1.00
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

222t - Diesel Engines
(Range - 8750nm)
5t - Basic Hydrophones

14t - 1918 FC
25t - LR Radio
25t - NF Devices

16t - 2x2x21in HW TT on Sides
4t - Additional Searchlights
40t - 2 x 10t Motor-Launch
8t - 50 x DC
2t - 2 x DC Thrower

20t - Berthing for 10 Additional Men (rescues/Seal Warriors)
30t - Enhanced Ship's Surgical Suite
10t - Additional DC/Firefighting Equipment

(70mm, 30mm, and 12mm guns are protected by weatherproof (incidentally splinter-resistant) shelters with ready-ammunition stored inside same)

(Note that this ship is 10% more structurally sound than required, additional bracing for ice/storms)

[Kaiser Kirk]

I strongly considered buying the surplus Wilno icebreakers, thinking they would be a good place to learn about how to build such a ship.
But considering my territorial extent, I don't have anything that could use it.
I don't know if Rocky's scrapped them, but might be a 'cheap' way for the same result.

[TacCovert4]

I strongly considered buying the surplus Wilno icebreakers, thinking they would be a good place to learn about how to build such a ship.
But considering my territorial extent, I don't have anything that could use it.
I don't know if Rocky's scrapped them, but might be a 'cheap' way for the same result.

The Wilno Icebreakers would probably make for a good option.  Unfortunately, we purchased these islands from Wilno, so there is a bit of national pride in play with our only real national presence there showing to be home-grown.  It shows our commitment to our most remote colony, and its importance to the Sultanate, that it gets its own station ships, even if they really are boutique designs.

[TacCovert4]

Time to start looking at carriers, now that research is complete.  First off, a simple single-hangar carrier, modestly protected against destroyers, modest air group.  Takeoff is from the forward deck that allows for direct takeoff from the hangar, landing is on the upper deck with elevators bringing the aircraft down. 

Martinique, Aztec Aircraft Carrier laid down 1926

Displacement:
   13,482 t light; 13,875 t standard; 15,399 t normal; 16,618 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (593.24 ft / 587.27 ft) x 68.90 ft x (23.79 / 25.28 ft)
   (180.82 m / 179.00 m) x 21.00 m  x (7.25 / 7.71 m)

Armament:
      12 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 250 per gun
     Quick firing guns in deck mounts, 1926 Model
     6 x Twin mounts on sides, evenly spread
      8 - 2.76" / 70.0 mm 50.0 cal guns - 11.09lbs / 5.03kg shells, 400 per gun
     Anti-air guns in deck mounts, 1926 Model
     8 x Single mounts on sides, evenly spread
      16 - 1.18" / 30.0 mm 50.0 cal guns - 0.86lbs / 0.39kg shells, 1,500 per gun
     Anti-air guns in deck mounts, 1926 Model
     16 x Single mounts on sides, evenly spread
      16 raised mounts
      Weight of broadside 490 lbs / 222 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.15" / 80 mm   381.73 ft / 116.35 m   9.84 ft / 3.00 m
   Ends:   1.97" / 50 mm   205.51 ft / 62.64 m   9.84 ft / 3.00 m
     Main Belt covers 100 % of normal length
     Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead - Additional damage containing bulkheads:
      1.18" / 30 mm   381.73 ft / 116.35 m   25.92 ft / 7.90 m
   Beam between torpedo bulkheads 45.93 ft / 14.00 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.97" / 50 mm         -               -
   2nd:   0.79" / 20 mm         -               -
   3rd:   0.79" / 20 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 2.36" / 60 mm
   Forecastle: 1.57" / 40 mm  Quarter deck: 1.57" / 40 mm

   - Conning towers: Forward 1.97" / 50 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 78,013 shp / 58,197 Kw = 29.00 kts
   Range 10,300nm at 14.00 kts
   Bunker at max displacement = 2,743 tons

Complement:
   690 - 898

Cost:
   £2.931 million / $11.726 million

Distribution of weights at normal displacement:
   Armament: 89 tons, 0.6 %
      - Guns: 89 tons, 0.6 %
   Armour: 2,324 tons, 15.1 %
      - Belts: 642 tons, 4.2 %
      - Torpedo bulkhead: 432 tons, 2.8 %
      - Armament: 44 tons, 0.3 %
      - Armour Deck: 1,180 tons, 7.7 %
      - Conning Tower: 26 tons, 0.2 %
   Machinery: 2,497 tons, 16.2 %
   Hull, fittings & equipment: 5,102 tons, 33.1 %
   Fuel, ammunition & stores: 1,917 tons, 12.4 %
   Miscellaneous weights: 3,470 tons, 22.5 %
      - Hull below water: 1,700 tons
      - Hull above water: 1,700 tons
      - Above deck: 70 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     30,719 lbs / 13,934 Kg = 1,006.8 x 3.9 " / 100 mm shells or 3.8 torpedoes
   Stability (Unstable if below 1.00): 1.35
   Metacentric height 4.8 ft / 1.5 m
   Roll period: 13.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.05
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has low forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.560 / 0.569
   Length to Beam Ratio: 8.52 : 1
   'Natural speed' for length: 24.23 kts
   Power going to wave formation at top speed: 56 %
   Trim (Max stability = 0, Max steadiness = 100): 35
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   25.00 %,  16.40 ft / 5.00 m,  16.40 ft / 5.00 m
      - Forward deck:   30.00 %,  32.81 ft / 10.00 m,  32.81 ft / 10.00 m
      - Aft deck:   35.00 %,  32.81 ft / 10.00 m,  32.81 ft / 10.00 m
      - Quarter deck:   10.00 %,  32.81 ft / 10.00 m,  32.81 ft / 10.00 m
      - Average freeboard:      28.71 ft / 8.75 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 119.1 %
      - Above water (accommodation/working, high = better): 258.2 %
   Waterplane Area: 28,504 Square feet or 2,648 Square metres
   Displacement factor (Displacement / loading): 139 %
   Structure weight / hull surface area: 99 lbs/sq ft or 482 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.89
      - Longitudinal: 2.86
      - Overall: 1.00
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

3400t - 40 Aircraft
25t - LR Radio
10t - Additional SR Radio (for air group control)
10t - 1918 FC
25t - NF Devices

Fo'cstle deck is take-off deck leading into Hangar. 

[TacCovert4]

For a couple thousand tons more, the same carrier.  Only now with an armored hangar, well, armored against long range light caliber fire, near misses, and splinters for the most part. 

Martinique, Aztec Aircraft Carrier laid down 1926

Displacement:
   15,997 t light; 16,424 t standard; 18,049 t normal; 19,350 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (594.44 ft / 587.27 ft) x 68.90 ft x (27.88 / 29.48 ft)
   (181.18 m / 179.00 m) x 21.00 m  x (8.50 / 8.98 m)

Armament:
      12 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 200 per gun
     Quick firing guns in deck mounts, 1926 Model
     6 x Twin mounts on sides, evenly spread
      8 - 2.76" / 70.0 mm 50.0 cal guns - 11.09lbs / 5.03kg shells, 300 per gun
     Anti-air guns in deck mounts, 1926 Model
     8 x Single mounts on sides, evenly spread
      16 - 1.18" / 30.0 mm 50.0 cal guns - 0.86lbs / 0.39kg shells, 1,000 per gun
     Anti-air guns in deck mounts, 1926 Model
     16 x Single mounts on sides, evenly spread
      16 raised mounts
      Weight of broadside 490 lbs / 222 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.15" / 80 mm   381.73 ft / 116.35 m   9.84 ft / 3.00 m
   Ends:   1.97" / 50 mm   205.51 ft / 62.64 m   9.84 ft / 3.00 m
   Upper:   2.36" / 60 mm   381.73 ft / 116.35 m   18.04 ft / 5.50 m
     Main Belt covers 100 % of normal length
     Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead - Additional damage containing bulkheads:
      1.18" / 30 mm   381.73 ft / 116.35 m   25.92 ft / 7.90 m
   Beam between torpedo bulkheads 45.93 ft / 14.00 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.97" / 50 mm         -               -
   2nd:   0.79" / 20 mm         -               -
   3rd:   0.79" / 20 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 3.54" / 90 mm
   Forecastle: 1.57" / 40 mm  Quarter deck: 1.57" / 40 mm

   - Conning towers: Forward 1.97" / 50 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 85,908 shp / 64,087 Kw = 29.00 kts
   Range 10,000nm at 14.00 kts
   Bunker at max displacement = 2,926 tons

Complement:
   778 - 1,012

Cost:
   £3.358 million / $13.431 million

Distribution of weights at normal displacement:
   Armament: 89 tons, 0.5 %
      - Guns: 89 tons, 0.5 %
   Armour: 3,521 tons, 19.5 %
      - Belts: 1,322 tons, 7.3 %
      - Torpedo bulkhead: 432 tons, 2.4 %
      - Armament: 44 tons, 0.2 %
      - Armour Deck: 1,694 tons, 9.4 %
      - Conning Tower: 29 tons, 0.2 %
   Machinery: 2,750 tons, 15.2 %
   Hull, fittings & equipment: 6,168 tons, 34.2 %
   Fuel, ammunition & stores: 2,052 tons, 11.4 %
   Miscellaneous weights: 3,470 tons, 19.2 %
      - Hull below water: 1,700 tons
      - Hull above water: 1,700 tons
      - Above deck: 70 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     37,672 lbs / 17,088 Kg = 1,234.7 x 3.9 " / 100 mm shells or 4.5 torpedoes
   Stability (Unstable if below 1.00): 1.19
   Metacentric height 4.0 ft / 1.2 m
   Roll period: 14.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.07
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has low forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.560 / 0.568
   Length to Beam Ratio: 8.52 : 1
   'Natural speed' for length: 24.23 kts
   Power going to wave formation at top speed: 56 %
   Trim (Max stability = 0, Max steadiness = 100): 35
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   25.00 %,  19.69 ft / 6.00 m,  19.69 ft / 6.00 m
      - Forward deck:   30.00 %,  39.37 ft / 12.00 m,  39.37 ft / 12.00 m
      - Aft deck:   35.00 %,  39.37 ft / 12.00 m,  39.37 ft / 12.00 m
      - Quarter deck:   10.00 %,  39.37 ft / 12.00 m,  39.37 ft / 12.00 m
      - Average freeboard:      34.45 ft / 10.50 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 108.6 %
      - Above water (accommodation/working, high = better): 274.7 %
   Waterplane Area: 28,504 Square feet or 2,648 Square metres
   Displacement factor (Displacement / loading): 142 %
   Structure weight / hull surface area: 100 lbs/sq ft or 487 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.83
      - Longitudinal: 5.25
      - Overall: 1.00
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

3400t - 40 Aircraft
25t - LR Radio
10t - Additional SR Radio (for air group control)
10t - 1918 FC
25t - NF Devices

Armored Box Carrier:
Flight Deck:  50mm
Hangar Floor:  40mm

Fo'cstle deck is take-off deck leading into Hangar. 

[TacCovert4]

And finally, double hangar variant of the above.  8 more aircraft, and the aircraft would have a roomier bit of space for work with the two hangars. 

Martinique, Aztec Aircraft Carrier laid down 1926

Displacement:
   15,608 t light; 16,026 t standard; 17,629 t normal; 18,911 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (595.63 ft / 587.27 ft) x 68.90 ft x (27.23 / 28.81 ft)
   (181.55 m / 179.00 m) x 21.00 m  x (8.30 / 8.78 m)

Armament:
      12 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 200 per gun
     Quick firing guns in deck mounts, 1926 Model
     6 x Twin mounts on sides, evenly spread
      8 - 2.76" / 70.0 mm 50.0 cal guns - 11.09lbs / 5.03kg shells, 300 per gun
     Anti-air guns in deck mounts, 1926 Model
     8 x Single mounts on sides, evenly spread
      16 - 1.18" / 30.0 mm 50.0 cal guns - 0.86lbs / 0.39kg shells, 1,000 per gun
     Anti-air guns in deck mounts, 1926 Model
     16 x Single mounts on sides, evenly spread
      16 raised mounts
      Weight of broadside 490 lbs / 222 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.15" / 80 mm   381.73 ft / 116.35 m   11.48 ft / 3.50 m
   Ends:   1.97" / 50 mm   205.51 ft / 62.64 m   11.48 ft / 3.50 m
     Main Belt covers 100 % of normal length
     Main belt does not fully cover magazines and engineering spaces

   - Torpedo Bulkhead - Additional damage containing bulkheads:
      1.18" / 30 mm   381.73 ft / 116.35 m   25.92 ft / 7.90 m
   Beam between torpedo bulkheads 45.93 ft / 14.00 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.97" / 50 mm         -               -
   2nd:   0.79" / 20 mm         -               -
   3rd:   0.79" / 20 mm         -               -

   - Armoured deck - single deck:
   For and Aft decks: 2.36" / 60 mm
   Forecastle: 1.57" / 40 mm  Quarter deck: 1.57" / 40 mm

   - Conning towers: Forward 1.97" / 50 mm, Aft 1.97" / 50 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 84,672 shp / 63,165 Kw = 29.00 kts
   Range 10,000nm at 14.00 kts
   Bunker at max displacement = 2,885 tons

Complement:
   764 - 994

Cost:
   £3.292 million / $13.166 million

Distribution of weights at normal displacement:
   Armament: 89 tons, 0.5 %
      - Guns: 89 tons, 0.5 %
   Armour: 2,462 tons, 14.0 %
      - Belts: 749 tons, 4.2 %
      - Torpedo bulkhead: 432 tons, 2.5 %
      - Armament: 44 tons, 0.2 %
      - Armour Deck: 1,180 tons, 6.7 %
      - Conning Towers: 57 tons, 0.3 %
   Machinery: 2,710 tons, 15.4 %
   Hull, fittings & equipment: 6,197 tons, 35.1 %
   Fuel, ammunition & stores: 2,021 tons, 11.5 %
   Miscellaneous weights: 4,150 tons, 23.5 %
      - Hull below water: 2,040 tons
      - Hull above water: 2,040 tons
      - Above deck: 70 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     35,051 lbs / 15,899 Kg = 1,148.8 x 3.9 " / 100 mm shells or 4.0 torpedoes
   Stability (Unstable if below 1.00): 1.21
   Metacentric height 4.0 ft / 1.2 m
   Roll period: 14.4 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.07
   Seaboat quality  (Average = 1.00): 2.00

Hull form characteristics:
   Hull has low forecastle,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.560 / 0.568
   Length to Beam Ratio: 8.52 : 1
   'Natural speed' for length: 24.23 kts
   Power going to wave formation at top speed: 56 %
   Trim (Max stability = 0, Max steadiness = 100): 35
   Bow angle (Positive = bow angles forward): 20.00 degrees
   Stern overhang: 0.00 ft / 0.00 m
   Freeboard (% = length of deck as a percentage of waterline length):
            Fore end,    Aft end
      - Forecastle:   25.00 %,  22.97 ft / 7.00 m,  22.97 ft / 7.00 m
      - Forward deck:   30.00 %,  39.37 ft / 12.00 m,  39.37 ft / 12.00 m
      - Aft deck:   35.00 %,  39.37 ft / 12.00 m,  39.37 ft / 12.00 m
      - Quarter deck:   10.00 %,  39.37 ft / 12.00 m,  39.37 ft / 12.00 m
      - Average freeboard:      35.27 ft / 10.75 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 116.2 %
      - Above water (accommodation/working, high = better): 279.8 %
   Waterplane Area: 28,504 Square feet or 2,648 Square metres
   Displacement factor (Displacement / loading): 143 %
   Structure weight / hull surface area: 99 lbs/sq ft or 482 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.82
      - Longitudinal: 5.63
      - Overall: 1.00
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform
   Excellent seaboat, comfortable, can fire her guns in the heaviest weather

4080t - 48 Aircraft (2 Hangars)
25t - LR Radio
10t - Additional SR Radio (for air group control)
10t - 1918 FC
25t - NF Devices

Fo'cstle deck is take-off deck leading into Upper Hangar.

[The Rock Doctor]

All fairly capable.

The main belt length may need adjustment?

The 100mm battery might be a bit light to fend off surface attackers, though?