Aztec Ship Designs 1921-1924

TacCovert4 · June 09, 2022, 06:02:36 PM

While there's a class of colonial station ships being built to replace the oldest ships in the fleet, a review of the fleet shows large deficits in modern cruisers and modern destroyers, especially given the dearth of Aztec capital ships such as battlecruisers that would normally be able to fill these roles in absentia of cruisers. Thus a Corvette and Frigate program are needed.

Shark-class, Aztec Corvette laid down 1924

Shark-class, Aztec Corvette laid down 1924

Displacement:
   7,277 t light; 7,617 t standard; 8,692 t normal; 9,552 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (566.10 ft / 557.74 ft) x 55.77 ft x (18.11 / 19.51 ft)
   (172.55 m / 170.00 m) x 17.00 m x (5.52 / 5.95 m)

Armament:
6 - 7.09" / 180 mm 50.0 cal guns - 188.38lbs / 85.45kg shells, 200 per gun
     Quick firing guns in deck and hoist mounts, 1924 Model
     3 x Twin mounts on centreline ends, majority forward
      1 raised mount - superfiring
8 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 200 per gun
     Quick firing guns in deck mounts, 1924 Model
     4 x Twin mounts on sides, evenly spread
3 - 2.76" / 70.0 mm 50.0 cal guns - 11.08lbs / 5.03kg shells, 300 per gun
     Anti-air guns in deck mounts, 1924 Model
     3 x Single mounts on centreline, aft evenly spread
      3 raised mounts
12 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.39kg shells, 1,000 per gun
     Anti-air guns in deck and hoist mounts, 1924 Model
     6 x Single mounts on sides, evenly spread
Weight of broadside 1,432 lbs / 650 kg

Armour:
- Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.94" / 100 mm   362.53 ft / 110.50 m   13.12 ft / 4.00 m
   Ends:   1.97" / 50 mm   195.18 ft / 59.49 m   9.84 ft / 3.00 m
     Main Belt covers 100 % of normal length

- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   4.53" / 115 mm   2.36" / 60 mm      4.53" / 115 mm
   2nd:   2.36" / 60 mm   1.38" / 35 mm        -
   4th:     -        -         0.79" / 20 mm

- Armoured deck - single deck:
   For and Aft decks: 2.17" / 55 mm
   Forecastle: 1.18" / 30 mm Quarter deck: 1.18" / 30 mm

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

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 66,617 shp / 49,696 Kw = 30.50 kts
   Range 10,000nm at 14.00 kts
   Bunker at max displacement = 1,936 tons

Complement:
   449 - 585

Cost:
   £2.156 million / $8.625 million

Distribution of weights at normal displacement:
   Armament: 321 tons, 3.7 %
     - Guns: 321 tons, 3.7 %
   Armour: 1,862 tons, 21.4 %
     - Belts: 908 tons, 10.5 %
     - Armament: 115 tons, 1.3 %
     - Armour Deck: 795 tons, 9.1 %
     - Conning Towers: 43 tons, 0.5 %
   Machinery: 2,194 tons, 25.2 %
   Hull, fittings & equipment: 2,682 tons, 30.9 %
   Fuel, ammunition & stores: 1,415 tons, 16.3 %
   Miscellaneous weights: 219 tons, 2.5 %
     - Hull above water: 46 tons
     - On freeboard deck: 107 tons
     - Above deck: 66 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     9,280 lbs / 4,210 Kg = 52.2 x 7.1 " / 180 mm shells or 1.4 torpedoes
   Stability (Unstable if below 1.00): 1.10
   Metacentric height 2.5 ft / 0.8 m
   Roll period: 14.9 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.47
   Seaboat quality (Average = 1.00): 1.05

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.540 / 0.551
   Length to Beam Ratio: 10.00 : 1
   'Natural speed' for length: 23.62 kts
   Power going to wave formation at top speed: 56 %
   Trim (Max stability = 0, Max steadiness = 100): 67
   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 %, 22.97 ft / 7.00 m, 20.51 ft / 6.25 m
     - Forward deck:   30.00 %, 20.51 ft / 6.25 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 %, 16.40 ft / 5.00 m, 16.40 ft / 5.00 m
     - Average freeboard:      18.04 ft / 5.50 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 97.9 %
      - Above water (accommodation/working, high = better): 158.3 %
   Waterplane Area: 21,507 Square feet or 1,998 Square metres
   Displacement factor (Displacement / loading): 112 %
   Structure weight / hull surface area: 84 lbs/sq ft or 411 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.88
      - Longitudinal: 1.05
      - Overall: 0.90
   Caution: Hull subject to strain in open-sea
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

32t - 2 x 4 x 21in HW TT on sides aft
60t - Provision for 2 x Catapult and 2 x Armed floatplane
45t - Power Assist for 180mm Mounts

25t - LR Wireless
25t - NF Devices
32t - 1918 FC

TacCovert4 · June 09, 2022, 06:37:03 PM

And a larger 'Frigate', using the more rapid-firing 180mm gun as opposed to the 9in and 11in guns of the 'Razee' type super-cruisers. This takes the Baja-class type to a slightly smaller gun but a more intense fire by adding 50% more guns.

Lake-class, Aztec Frigate laid down 1924

Displacement:
   13,238 t light; 13,853 t standard; 15,388 t normal; 16,616 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (654.98 ft / 646.33 ft) x 70.54 ft x (21.10 / 22.43 ft)
   (199.64 m / 197.00 m) x 21.50 m x (6.43 / 6.84 m)

Armament:
12 - 7.09" / 180 mm 50.0 cal guns - 188.38lbs / 85.45kg shells, 200 per gun
     Quick firing guns in turret on barbette mounts, 1924 Model
     4 x Twin mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
12 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 200 per gun
     Quick firing guns in deck mounts, 1924 Model
     6 x Twin mounts on sides, evenly spread
4 - 2.76" / 70.0 mm 50.0 cal guns - 11.08lbs / 5.03kg shells, 300 per gun
     Anti-air guns in deck mounts, 1924 Model
     4 x Single mounts on sides, evenly spread
      4 raised mounts
12 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.39kg shells, 1,000 per gun
     Anti-air guns in deck and hoist mounts, 1924 Model
     6 x Single mounts on sides, evenly spread
Weight of broadside 2,703 lbs / 1,226 kg

Armour:
- Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   4.72" / 120 mm   439.50 ft / 133.96 m   16.40 ft / 5.00 m
   Ends:   2.36" / 60 mm   206.79 ft / 63.03 m   9.84 ft / 3.00 m
     Main Belt covers 105 % of normal length

- Torpedo Bulkhead - Additional damage containing bulkheads:
      1.57" / 40 mm   439.50 ft / 133.96 m   19.69 ft / 6.00 m
   Beam between torpedo bulkheads 55.77 ft / 17.00 m

- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   4.92" / 125 mm   3.15" / 80 mm      4.92" / 125 mm
   2nd:   2.36" / 60 mm   1.38" / 35 mm        -
   4th:     -        -         0.79" / 20 mm

- Armoured deck - single deck:
   For and Aft decks: 2.76" / 70 mm
   Forecastle: 1.06" / 27 mm Quarter deck: 1.57" / 40 mm

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

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 91,422 shp / 68,201 Kw = 30.50 kts
   Range 10,000nm at 14.00 kts
   Bunker at max displacement = 2,763 tons

Complement:
   690 - 898

Cost:
   £3.543 million / $14.172 million

Distribution of weights at normal displacement:
   Armament: 646 tons, 4.2 %
     - Guns: 646 tons, 4.2 %
   Armour: 4,259 tons, 27.7 %
     - Belts: 1,579 tons, 10.3 %
     - Torpedo bulkhead: 504 tons, 3.3 %
     - Armament: 601 tons, 3.9 %
     - Armour Deck: 1,511 tons, 9.8 %
     - Conning Towers: 63 tons, 0.4 %
   Machinery: 3,011 tons, 19.6 %
   Hull, fittings & equipment: 5,114 tons, 33.2 %
   Fuel, ammunition & stores: 2,150 tons, 14.0 %
   Miscellaneous weights: 207 tons, 1.3 %
     - Hull above water: 33 tons
     - On freeboard deck: 92 tons
     - Above deck: 82 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     21,289 lbs / 9,656 Kg = 119.6 x 7.1 " / 180 mm shells or 3.3 torpedoes
   Stability (Unstable if below 1.00): 1.12
   Metacentric height 3.6 ft / 1.1 m
   Roll period: 15.5 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.40
   Seaboat quality (Average = 1.00): 1.07

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.560 / 0.569
   Length to Beam Ratio: 9.16 : 1
   'Natural speed' for length: 25.42 kts
   Power going to wave formation at top speed: 54 %
   Trim (Max stability = 0, Max steadiness = 100): 66
   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:   18.00 %, 23.79 ft / 7.25 m, 21.33 ft / 6.50 m
     - Forward deck:   30.00 %, 21.33 ft / 6.50 m, 18.04 ft / 5.50 m
     - Aft deck:   38.00 %, 18.04 ft / 5.50 m, 18.04 ft / 5.50 m
     - Quarter deck:   14.00 %, 18.04 ft / 5.50 m, 18.04 ft / 5.50 m
     - Average freeboard:      19.30 ft / 5.88 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 102.1 %
      - Above water (accommodation/working, high = better): 166.4 %
   Waterplane Area: 32,117 Square feet or 2,984 Square metres
   Displacement factor (Displacement / loading): 119 %
   Structure weight / hull surface area: 115 lbs/sq ft or 563 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 1.00
      - Longitudinal: 1.00
      - Overall: 1.00
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

32t - 2 x 4 x 21in HW TT on sides aft
60t - Provision for 2 x Catapult and 2 x Armed floatplane

25t - LR Wireless
25t - NF Devices
65t - 1918 FC

TacCovert4 · June 09, 2022, 06:41:53 PM

And with an abandonment of the concept of a 130mm cruiser, comes the design studies for a 2000t DD operating as a gunboat destroyer and leader for a destroyer or GTB squadron as part of the fleet.

I-Class, Aztec Destroyer laid down 1924

Displacement:
   2,000 t light; 2,097 t standard; 2,348 t normal; 2,550 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (400.87 ft / 393.70 ft) x 36.09 ft x (10.52 / 11.23 ft)
   (122.18 m / 120.00 m) x 11.00 m x (3.21 / 3.42 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, 1924 Model
     3 x Twin mounts on centreline ends, majority forward
      1 raised mount - superfiring
6 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.39kg shells, 1,000 per gun
     Quick firing guns in deck and hoist mounts, 1924 Model
     2 x Twin mounts on sides, forward deck aft
     1 x Twin mount on centreline, aft deck centre
      1 raised mount
Weight of broadside 431 lbs / 196 kg

Armour:
- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.06" / 27 mm   1.06" / 27 mm      1.06" / 27 mm
   2nd:     -        -         0.79" / 20 mm

- Box over magazines:
   1.06" / 27 mm

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

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 43,642 shp / 32,557 Kw = 32.25 kts
   Range 5,000nm at 14.00 kts
   Bunker at max displacement = 453 tons

Complement:
   168 - 219

Cost:
   £0.871 million / $3.483 million

Distribution of weights at normal displacement:
   Armament: 104 tons, 4.4 %
     - Guns: 104 tons, 4.4 %
   Armour: 45 tons, 1.9 %
     - Armament: 24 tons, 1.0 %
     - Armour Deck: 17 tons, 0.7 %
     - Conning Tower: 4 tons, 0.2 %
   Machinery: 1,184 tons, 50.4 %
   Hull, fittings & equipment: 639 tons, 27.2 %
   Fuel, ammunition & stores: 349 tons, 14.8 %
   Miscellaneous weights: 27 tons, 1.1 %
     - Hull above water: 6 tons
     - On freeboard deck: 16 tons
     - Above deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     599 lbs / 272 Kg = 8.9 x 5.1 " / 130 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.12
   Metacentric height 1.3 ft / 0.4 m
   Roll period: 13.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.80
   Seaboat quality (Average = 1.00): 1.02

Hull form characteristics:
   Hull has a flush deck,
     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): 69
   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 %, 19.69 ft / 6.00 m, 18.04 ft / 5.50 m
     - Forward deck:   30.00 %, 18.04 ft / 5.50 m, 14.76 ft / 4.50 m
     - Aft deck:   35.00 %, 14.76 ft / 4.50 m, 14.76 ft / 4.50 m
     - Quarter deck:   15.00 %, 14.76 ft / 4.50 m, 14.76 ft / 4.50 m
     - Average freeboard:      16.04 ft / 4.89 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 181.5 %
      - Above water (accommodation/working, high = better): 174.5 %
   Waterplane Area: 9,916 Square feet or 921 Square metres
   Displacement factor (Displacement / loading): 69 %
   Structure weight / hull surface area: 37 lbs/sq ft or 181 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.42
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

11t - 1918 FC
16t - 1x4x21in HW TT Centerline

The Rock Doctor · June 09, 2022, 07:43:46 PM

Should that be four triples/3-gun mountings on the 13,000 t ship?

TacCovert4 · June 09, 2022, 09:47:07 PM

Quote from: The Rock Doctor on June 09, 2022, 07:43:46 PM
Should that be four triples/3-gun mountings on the 13,000 t ship?

It should be 4 x 3 gun mounts. It's always something that doesn't affect the balance of a ship that I miss. But yes, 4 x 3 gun turrets, basically a Town class scaled up to 7in guns.

TacCovert4 · June 13, 2022, 01:32:51 PM

Aside from the clerical error on the Frigate, any thoughts as to the three ships posted?

The Rock Doctor · June 13, 2022, 05:07:15 PM

The I-class is capable as a surface combatant but I'd rather have more misc. weight than protection over the magazines.

The two larger ships are certainly capable. I feel like I'd want more speed, and perhaps skip the torpedo protection on the larger unit, but they're well protected.

TacCovert4 · June 22, 2022, 09:17:13 AM

Quote from: The Rock Doctor on June 13, 2022, 05:07:15 PM
The I-class is capable as a surface combatant but I'd rather have more misc. weight than protection over the magazines.

The two larger ships are certainly capable. I feel like I'd want more speed, and perhaps skip the torpedo protection on the larger unit, but they're well protected.

That's something that I've been thinking about. And then Drachinifel's wednesday video noted that the Fletchers were built with splinter protection for vital areas because USN studies had shown that a number of DDs had been lost or crippled by near misses causing blast and splinter damage from as far as 50yds away.

27mm, per the rules, gives splinter protection against 162mm, and HE protection against 216mm. So that's probably too heavy. I could take that down to 24mm, which would give protection against the 140mm guns that seem to be the largest guns on comparable ships. Maybe even to 22mm, which would protect against the 130s the ships themselves are carrying, since 140mm armed DDs are relatively few and far between, 140mm being more of a small cruiser armament.

I'll play around with the design going down to 24 and 22mm of plating respectively, maybe even going to a belt and flat deck at 22mm. Protected deck wouldn't really work as the below water usage is so high you'd have at least half the boilers exposed above the deck.

TacCovert4 · July 03, 2022, 10:55:32 AM

Changes made to the I class DD. Notably the armor has been removed in favor of an additional Quad TT launcher and a minimal ASW capability.

I-Class, Aztec Destroyer laid down 1924

Displacement:
   2,000 t light; 2,097 t standard; 2,348 t normal; 2,550 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (400.87 ft / 393.70 ft) x 36.09 ft x (10.52 / 11.23 ft)
   (122.18 m / 120.00 m) x 11.00 m x (3.21 / 3.42 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, 1924 Model
     3 x Twin mounts on centreline ends, majority forward
      1 raised mount - superfiring
6 - 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, 1924 Model
     2 x Twin mounts on sides, forward deck aft
     1 x Twin mount on centreline, aft deck centre
      1 raised mount
Weight of broadside 431 lbs / 195 kg

Armour:
- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.06" / 27 mm   0.87" / 22 mm      0.87" / 22 mm
   2nd:     -        -         0.79" / 20 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 43,642 shp / 32,557 Kw = 32.25 kts
   Range 5,000nm at 14.00 kts
   Bunker at max displacement = 453 tons

Complement:
   168 - 219

Cost:
   £0.870 million / $3.480 million

Distribution of weights at normal displacement:
   Armament: 104 tons, 4.4 %
     - Guns: 104 tons, 4.4 %
   Armour: 20 tons, 0.8 %
     - Armament: 20 tons, 0.8 %
   Machinery: 1,183 tons, 50.4 %
   Hull, fittings & equipment: 633 tons, 27.0 %
   Fuel, ammunition & stores: 349 tons, 14.8 %
   Miscellaneous weights: 60 tons, 2.6 %
     - Hull below water: 5 tons
     - Hull above water: 6 tons
     - On freeboard deck: 44 tons
     - Above deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     594 lbs / 269 Kg = 8.9 x 5.1 " / 130 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.11
   Metacentric height 1.3 ft / 0.4 m
   Roll period: 13.2 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.81
   Seaboat quality (Average = 1.00): 1.02

Hull form characteristics:
   Hull has a flush deck,
     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): 69
   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 %, 19.69 ft / 6.00 m, 18.04 ft / 5.50 m
     - Forward deck:   30.00 %, 18.04 ft / 5.50 m, 14.76 ft / 4.50 m
     - Aft deck:   35.00 %, 14.76 ft / 4.50 m, 14.76 ft / 4.50 m
     - Quarter deck:   15.00 %, 14.76 ft / 4.50 m, 14.76 ft / 4.50 m
     - Average freeboard:      16.04 ft / 4.89 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 181.5 %
      - Above water (accommodation/working, high = better): 174.5 %
   Waterplane Area: 9,916 Square feet or 921 Square metres
   Displacement factor (Displacement / loading): 69 %
   Structure weight / hull surface area: 37 lbs/sq ft or 179 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.41
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

11t - 1918 FC
32t - 2x4x21in HW TT Centerline
5t - Basic Hydrophones
2t - 2 x DC Thrower
10t - 50 x 195kg DC

TacCovert4 · July 03, 2022, 11:06:22 AM

And a corresponding design for a 1924 Pacific DD. While the guns have been reduced to 100mm guns, two more have been added, the overall reduced topweight allowing for substantially more fuel to be placed aboard. Half of the torpedo armament has been sacrificed in favor of full-up ASW facilities, as this class would be expected to be more general purpose as opposed to the 'Leader' variant in the I class.

J-Class, Aztec Destroyer laid down 1924

Displacement:
   2,000 t light; 2,082 t standard; 2,491 t normal; 2,819 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (400.27 ft / 393.70 ft) x 38.06 ft x (10.78 / 11.88 ft)
   (122.00 m / 120.00 m) x 11.60 m x (3.29 / 3.62 m)

Armament:
8 - 3.94" / 100 mm 50.0 cal guns - 32.30lbs / 14.65kg shells, 200 per gun
     Quick firing guns in deck mounts, 1924 Model
     4 x Twin mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
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, 1924 Model
     4 x Twin mounts on sides, evenly spread
Weight of broadside 265 lbs / 120 kg

Armour:
- Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.06" / 27 mm   0.87" / 22 mm        -
   2nd:     -        -         0.79" / 20 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 44,019 shp / 32,838 Kw = 32.00 kts
   Range 8,000nm at 14.00 kts
   Bunker at max displacement = 737 tons

Complement:
   176 - 229

Cost:
   £0.823 million / $3.291 million

Distribution of weights at normal displacement:
   Armament: 46 tons, 1.8 %
     - Guns: 46 tons, 1.8 %
   Armour: 22 tons, 0.9 %
     - Armament: 22 tons, 0.9 %
   Machinery: 1,293 tons, 51.9 %
   Hull, fittings & equipment: 575 tons, 23.1 %
   Fuel, ammunition & stores: 492 tons, 19.7 %
   Miscellaneous weights: 64 tons, 2.6 %
     - Hull below water: 15 tons
     - Hull above water: 6 tons
     - On freeboard deck: 38 tons
     - Above deck: 5 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     752 lbs / 341 Kg = 24.7 x 3.9 " / 100 mm shells or 0.4 torpedoes
   Stability (Unstable if below 1.00): 1.43
   Metacentric height 2.2 ft / 0.7 m
   Roll period: 10.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.18
   Seaboat quality (Average = 1.00): 1.06

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.540 / 0.554
   Length to Beam Ratio: 10.34 : 1
   'Natural speed' for length: 19.84 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 66
   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, 18.04 ft / 5.50 m
     - Forward deck:   30.00 %, 18.04 ft / 5.50 m, 14.76 ft / 4.50 m
     - Aft deck:   35.00 %, 14.76 ft / 4.50 m, 14.76 ft / 4.50 m
     - Quarter deck:   15.00 %, 14.76 ft / 4.50 m, 14.76 ft / 4.50 m
     - Average freeboard:      15.91 ft / 4.85 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 175.0 %
      - Above water (accommodation/working, high = better): 174.0 %
   Waterplane Area: 10,359 Square feet or 962 Square metres
   Displacement factor (Displacement / loading): 80 %
   Structure weight / hull surface area: 33 lbs/sq ft or 159 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.24
      - Overall: 0.54
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

11t - 1918 FC
16t - 2x4x21in HW TT Centerline
15t - Enhanced Hydrophones 1915
2t - 2 x DC Thrower
20t - 100 x 195kg DC

The Rock Doctor · July 05, 2022, 06:59:41 AM

I like the balance of the second type a bit more than the first.

Does the I-class have sufficient legs to get over to Aztec Africa without refueling?

TacCovert4 · July 05, 2022, 02:12:42 PM

Not at 14kts. The I class could do it with fuel left over at 10kts, at 14kts they'd be running on fumes to do Martinique-Luanda. At the same 10kts, a J-class could do Veracruz-Luanda without any problems and with fuel to spare, it'd be close at 14kts.

The dichotomy with the Sultanate is that it has far-flung colonies, but then it has the 'twin lakes' of the Gulf and Caribbean that trend towards fast and nasty with range being a secondary concern.

TacCovert4 · July 05, 2022, 08:51:00 PM

The killer with the I-class, or really any of the big DDs, is trying to cram 6 130mm guns, with hoists, onto a proper DD in the time period.

TacCovert4 · July 05, 2022, 10:04:01 PM

Been fiddling with the 500t designs for a while, trying to make it work. I think I've finally hit the closest to the sweet spot I can do for 1924. I present, the V-class large torpedo boat. Sporting 6 heavyweight torpedoes, 2 100mm guns, 4 AA/small craft 30mm guns, and proper fire control and short-range Comms, it packs a serious wallop for its size. Top speed: 33.5kts

GTB-V, Aztec Torpedo Boat laid down 1924

Displacement:
   500 t light; 519 t standard; 584 t normal; 637 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (305.90 ft / 301.84 ft) x 25.82 ft x (6.56 / 6.94 ft)
   (93.24 m / 92.00 m) x 7.87 m x (2.00 / 2.12 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, 1924 Model
     2 x Single mounts on centreline, forward evenly spread
      1 raised mount
4 - 1.18" / 30.0 mm 50.0 cal guns - 0.87lbs / 0.40kg shells, 1,000 per gun
     Anti-air guns in deck mounts, 1924 Model
     4 x Single mounts on sides, evenly spread
Weight of broadside 68 lbs / 31 kg

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 15,963 shp / 11,908 Kw = 31.00 kts
   Range 3,000nm at 14.00 kts
   Bunker at max displacement = 118 tons

Complement:
   59 - 77

Cost:
   £0.195 million / $0.779 million

Distribution of weights at normal displacement:
   Armament: 14 tons, 2.4 %
     - Guns: 14 tons, 2.4 %
   Machinery: 298 tons, 51.0 %
   Hull, fittings & equipment: 162 tons, 27.7 %
   Fuel, ammunition & stores: 84 tons, 14.5 %
   Miscellaneous weights: 26 tons, 4.4 %
     - On freeboard deck: 24 tons
     - Above deck: 2 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     167 lbs / 76 Kg = 5.5 x 3.9 " / 100 mm shells or 0.2 torpedoes
   Stability (Unstable if below 1.00): 1.11
   Metacentric height 0.8 ft / 0.2 m
   Roll period: 12.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 60 %
         - Recoil effect (Restricted arc if above 1.00): 0.17
   Seaboat quality (Average = 1.00): 0.70

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.400 / 0.412
   Length to Beam Ratio: 11.69 : 1
   'Natural speed' for length: 17.37 kts
   Power going to wave formation at top speed: 63 %
   Trim (Max stability = 0, Max steadiness = 100): 86
   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 %, 11.15 ft / 3.40 m, 10.56 ft / 3.22 m
     - Forward deck:   30.00 %, 10.56 ft / 3.22 m, 8.69 ft / 2.65 m
     - Aft deck:   35.00 %, 8.69 ft / 2.65 m, 8.04 ft / 2.45 m
     - Quarter deck:   15.00 %, 8.04 ft / 2.45 m, 8.04 ft / 2.45 m
     - Average freeboard:      9.18 ft / 2.80 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 171.5 %
      - Above water (accommodation/working, high = better): 138.6 %
   Waterplane Area: 4,797 Square feet or 446 Square metres
   Displacement factor (Displacement / loading): 52 %
   Structure weight / hull surface area: 22 lbs/sq ft or 109 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 0.72
      - Overall: 0.51
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Poor seaboat, wet and uncomfortable, reduced performance in heavy weather

24 - 2 x 3 x 21in HW TT Centerline
2t - 1918 FC

The Rock Doctor · July 06, 2022, 07:19:10 AM

At first blush I was like, "Eek, that L:B ratio", but it's not as high as I thought.

Certainly a capable unit. I was playing along similar lines last night with a slower vessel with better seakeeping (and a trade of torps for basic ASW, since that's my thing).

But as a pure anti-surface threat in good waters, this is definitely a notable one.