Aztec Ship Designs 1921-1924

[Kaiser Kirk]

If you're looking to use existing weapons, then yes the 180 is more flexible.
The later naval gun techs allow heavier shells and longer barrels, which can
allow for 'better' smaller weapons.

The N7 rule I made up (enshrined in Gun Research) that is probably vaguely real is the Bore in CM = valid spotting range in KM,
the 18cm allows you to hit the horizon more accurately, so that's an advantage on the 15cm.
Again though, if ships are closing fast, that 4000m may not be a big deal.

[TacCovert4]

If you're looking to use existing weapons, then yes the 180 is more flexible.
The later naval gun techs allow heavier shells and longer barrels, which can
allow for 'better' smaller weapons.

The N7 rule I made up (enshrined in Gun Research) that is probably vaguely real is the Bore in CM = valid spotting range in KM,
the 18cm allows you to hit the horizon more accurately, so that's an advantage on the 15cm.
Again though, if ships are closing fast, that 4000m may not be a big deal.

The damage reports etc showed that the armor plus distance really helped.  My splendid cats are more heavily armored and have 180mm guns, they would have probably held up better than the eagles.   But I'm going to be aiming to maximize long range, that and 180mm is more likely to smash armor in, or do instantly fatal damage to destroyers and small cruisers.

One potential option on the 6000 tonner is to pull the 100mm secondary battery off, reduce the armor a bit, and see if I can fit an extra pair of 180mm guns to her.  Upside, more main gun firepower and more effective at range.  Downside, the 180s become the sole battery.

[Kaiser Kirk]

The damage reports etc showed that the armor plus distance really helped. 

That is correct. There was a considerable period that Mayan shells were not penetrating the heavier armor. Even the Eagles lighter armor marked them as clearly superior to the unarmored small cruisers on the other side. 
The Aztecs were doing a good job of keeping range open with the R's - Weapons- Eagles, and the DDs coming up on the outside.
There came a point at which the DDs were edging ahead, and  leading Eagles and DDs could see the prospect of clearing the Mayan wing- and almost scraping off the Mayan cruisers/DDs there to prep for a "L" torpedo attack that would be hard to dodge. 
Before matters quite got to that point the Mayan line of advance reacted and shifted, and the range fell down- and the Mayans shifted fire to the lighter units for the cruisers and left the heavier to the BBs. The Mayan BB setup also limited their arcs from further out- and so were ineffective early, but were now able to bear more guns.

[TacCovert4]

Yep.  Things I learned here were that my ships were designed too fast.  Too much focus on speed, necessary against Rome, meant that they didn't have the staying power.  I wasn't really satisfied with the performance of the Eagles.  The Weapons did ok.  And the Rs were also ok. 

The Uhlan class fix all the problems the Rs had, with more main guns and a good balance.  The original 12 gun Lake class would fix the Weapon class....except I have to get ships built in numbers and relatively soon.  So given the need to build ships small enough that I can produce them quickly to replace losses, I'm left with figuring out the balance of firepower and armor.

[Kaiser Kirk]

I will say that before the battle I was pleased with the final form of my Artesmia II class frigates.
They really are meant as anti-DD or commerce, but boy they would be unhappy against a cruiser.
So something like this, where the DD & cruisers are mixed, not a good situation for them.
So now...I'm reconsidering if I should shave speed for more armor and swap to 165mm like one
of the variants I looked at.

[TacCovert4]

And a true war emergency program:

Town-Class, Aztec Corvette laid down 1924

Displacement:
   6,000 t light; 6,279 t standard; 7,044 t normal; 7,656 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (488.66 ft / 482.28 ft) x 59.06 ft x (16.03 / 17.12 ft)
   (148.94 m / 147.00 m) x 18.00 m  x (4.89 / 5.22 m)

Armament:
      8 - 7.09" / 180 mm 50.0 cal guns - 188.39lbs / 85.45kg shells, 160 per gun
     Quick firing guns in deck and hoist 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
     Anti-air guns in deck and hoist mounts, 1924 Model
     4 x Twin mounts on sides, evenly spread
      Weight of broadside 1,514 lbs / 687 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   3.15" / 80 mm   327.95 ft / 99.96 m   11.48 ft / 3.50 m
   Ends:   1.57" / 40 mm   154.30 ft / 47.03 m   9.84 ft / 3.00 m
     Main Belt covers 105 % of normal length

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   3.15" / 80 mm   1.97" / 50 mm      2.36" / 60 mm
   3rd:         -            -         0.79" / 20 mm

   - Protected deck - single deck:
   For and Aft decks: 1.77" / 45 mm
   Forecastle: 1.06" / 27 mm  Quarter deck: 1.38" / 35 mm

   - Conning towers: Forward 3.15" / 80 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 52,521 shp / 39,181 Kw = 29.00 kts
   Range 8,000nm at 14.00 kts
   Bunker at max displacement = 1,378 tons

Complement:
   383 - 499

Cost:
   £1.888 million / $7.552 million

Distribution of weights at normal displacement:
   Armament: 356 tons, 5.1 %
      - Guns: 356 tons, 5.1 %
   Armour: 1,308 tons, 18.6 %
      - Belts: 583 tons, 8.3 %
      - Armament: 82 tons, 1.2 %
      - Armour Deck: 618 tons, 8.8 %
      - Conning Tower: 25 tons, 0.4 %
   Machinery: 1,730 tons, 24.6 %
   Hull, fittings & equipment: 2,469 tons, 35.0 %
   Fuel, ammunition & stores: 1,044 tons, 14.8 %
   Miscellaneous weights: 137 tons, 1.9 %
      - Hull above water: 58 tons
      - On freeboard deck: 36 tons
      - Above deck: 43 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     8,046 lbs / 3,649 Kg = 45.2 x 7.1 " / 180 mm shells or 1.4 torpedoes
   Stability (Unstable if below 1.00): 1.12
   Metacentric height 2.8 ft / 0.9 m
   Roll period: 14.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.55
   Seaboat quality  (Average = 1.00): 1.01

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.540 / 0.550
   Length to Beam Ratio: 8.17 : 1
   'Natural speed' for length: 21.96 kts
   Power going to wave formation at top speed: 59 %
   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:   18.00 %,  23.79 ft / 7.25 m,  20.51 ft / 6.25 m
      - Forward deck:   30.00 %,  20.51 ft / 6.25 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,  16.40 ft / 5.00 m
      - Average freeboard:      18.98 ft / 5.78 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 101.7 %
      - Above water (accommodation/working, high = better): 182.0 %
   Waterplane Area: 19,692 Square feet or 1,829 Square metres
   Displacement factor (Displacement / loading): 110 %
   Structure weight / hull surface area: 89 lbs/sq ft or 433 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.85
      - Longitudinal: 1.46
      - 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

25t - LR Radio
36t - 1918 FC
16t - 2 x 2 x 21in HW TT on sides aft
60t - Electric T&E for Main Battery

[TacCovert4]

Going back to the 1924 Fleet Destroyer, when you take an I-class and change its 130mm guns for 100s, you can significantly bump up the sheer numbers of guns.  As was noted in the battle off Veracruz, 6 guns is insufficient for accurately spotting fire at range.  And with 100mm twins, you get the ability to run a much heavier battery for a rapid-fire at closer ranges which DDs always seem to find themselves at anyway.  More range, speed, and stability/flotation than the previous I-class design.  And because there was so much strength left over, thicker splinter protection for the magazines, bridge, and all guns. 

I-Class, Aztec Destroyer laid down 1924

Displacement:
   2,000 t light; 2,087 t standard; 2,363 t normal; 2,585 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (399.97 ft / 393.70 ft) x 36.09 ft x (10.52 / 11.30 ft)
   (121.91 m / 120.00 m) x 11.00 m  x (3.21 / 3.44 m)

Armament:
      10 - 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
     1 x Twin mount on centreline, forward deck centre
      1 double 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, 1924 Model
     4 x Twin mounts on sides, evenly spread
      Weight of broadside 330 lbs / 150 kg

Armour:
   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   1.18" / 30 mm   1.18" / 30 mm            -
   2nd:   0.79" / 20 mm         -         0.79" / 20 mm

   - Box over magazines:
   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, 45,972 shp / 34,295 Kw = 32.60 kts
   Range 5,500nm at 14.00 kts
   Bunker at max displacement = 498 tons

Complement:
   169 - 220

Cost:
   £0.822 million / $3.287 million

Distribution of weights at normal displacement:
   Armament: 56 tons, 2.4 %
      - Guns: 56 tons, 2.4 %
   Armour: 66 tons, 2.8 %
      - Armament: 44 tons, 1.8 %
      - Armour Deck: 18 tons, 0.8 %
      - Conning Tower: 5 tons, 0.2 %
   Machinery: 1,266 tons, 53.6 %
   Hull, fittings & equipment: 564 tons, 23.9 %
   Fuel, ammunition & stores: 364 tons, 15.4 %
   Miscellaneous weights: 47 tons, 2.0 %
      - Hull above water: 3 tons
      - On freeboard deck: 16 tons
      - Above deck: 28 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     622 lbs / 282 Kg = 20.4 x 3.9 " / 100 mm shells or 0.3 torpedoes
   Stability (Unstable if below 1.00): 1.26
   Metacentric height 1.6 ft / 0.5 m
   Roll period: 11.8 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.34
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has a flush deck,
     a normal bow and a cruiser stern
   Block coefficient (normal/deep): 0.554 / 0.564
   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): 70
   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 %,  17.22 ft / 5.25 m,  16.73 ft / 5.10 m
      - Forward deck:   30.00 %,  16.73 ft / 5.10 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:      15.49 ft / 4.72 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 181.4 %
      - Above water (accommodation/working, high = better): 170.6 %
   Waterplane Area: 9,948 Square feet or 924 Square metres
   Displacement factor (Displacement / loading): 71 %
   Structure weight / hull surface area: 33 lbs/sq ft or 161 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.23
      - Overall: 0.55
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

6t - 1918 FC
16t - 1x4x21in HW TT Centerline
25t - LR Radio

[TacCovert4]

A potential Frigate/Razee design:

Lake-class, Aztec Frigate laid down 1924

Displacement:
   12,491 t light; 13,113 t standard; 14,531 t normal; 15,666 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (598.61 ft / 590.55 ft) x 73.82 ft x (20.83 / 22.13 ft)
   (182.46 m / 180.00 m) x 22.50 m  x (6.35 / 6.74 m)

Armament:
      6 - 9.45" / 240 mm 50.0 cal guns - 446.53lbs / 202.54kg shells, 150 per gun
     Breech loading guns in turret on barbette mounts, 1924 Model
     2 x 3-gun mounts on centreline, forward evenly spread
      1 raised mount
      12 - 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
     4 x Twin mounts on sides, aft evenly spread
     2 x Single mounts on centreline, aft deck aft
      1 raised mount - superfiring
      4 - 2.76" / 70.0 mm 50.0 cal guns - 11.09lbs / 5.03kg shells, 300 per gun
     Anti-air guns in deck mounts, 1924 Model
     4 x Single mounts on sides, aft evenly spread
      4 raised mounts
      12 - 1.18" / 30.0 mm 50.0 cal guns - 0.86lbs / 0.39kg shells, 1,000 per gun
     Anti-air guns in deck and hoist mounts, 1924 Model
     2 x Twin mounts on sides, aft deck centre
     4 x Twin mounts on sides, forward evenly spread
      Weight of broadside 3,585 lbs / 1,626 kg

Armour:
   - Belts:      Width (max)   Length (avg)      Height (avg)
   Main:   5.91" / 150 mm   401.57 ft / 122.40 m   11.48 ft / 3.50 m
   Ends:   2.36" / 60 mm   188.94 ft / 57.59 m   11.48 ft / 3.50 m
     Main Belt covers 105 % of normal length

   - Torpedo Bulkhead - Additional damage containing bulkheads:
      1.57" / 40 mm   401.57 ft / 122.40 m   19.29 ft / 5.88 m
   Beam between torpedo bulkheads 57.41 ft / 17.50 m

   - Gun armour:   Face (max)   Other gunhouse (avg)   Barbette/hoist (max)
   Main:   6.30" / 160 mm   4.33" / 110 mm      5.91" / 150 mm
   2nd:   2.76" / 70 mm   1.57" / 40 mm      2.76" / 70 mm
   4th:         -            -         0.79" / 20 mm

   - Protected deck - single deck:
   For and Aft decks: 2.36" / 60 mm
   Forecastle: 1.18" / 30 mm  Quarter deck: 1.57" / 40 mm

   - Conning towers: Forward 3.94" / 100 mm, Aft 3.94" / 100 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 4 shafts, 76,218 shp / 56,859 Kw = 29.00 kts
   Range 9,600nm at 14.00 kts
   Bunker at max displacement = 2,553 tons

Complement:
   661 - 860

Cost:
   £3.590 million / $14.361 million

Distribution of weights at normal displacement:
   Armament: 1,063 tons, 7.3 %
      - Guns: 1,063 tons, 7.3 %
   Armour: 3,692 tons, 25.4 %
      - Belts: 1,329 tons, 9.1 %
      - Torpedo bulkhead: 451 tons, 3.1 %
      - Armament: 548 tons, 3.8 %
      - Armour Deck: 1,262 tons, 8.7 %
      - Conning Towers: 101 tons, 0.7 %
   Machinery: 2,510 tons, 17.3 %
   Hull, fittings & equipment: 5,009 tons, 34.5 %
   Fuel, ammunition & stores: 2,040 tons, 14.0 %
   Miscellaneous weights: 217 tons, 1.5 %
      - Hull above water: 57 tons
      - On freeboard deck: 60 tons
      - Above deck: 100 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     19,746 lbs / 8,956 Kg = 46.8 x 9.4 " / 240 mm shells or 3.3 torpedoes
   Stability (Unstable if below 1.00): 1.08
   Metacentric height 3.7 ft / 1.1 m
   Roll period: 16.1 seconds
   Steadiness   - As gun platform (Average = 50 %): 70 %
         - Recoil effect (Restricted arc if above 1.00): 0.53
   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): 0.560 / 0.568
   Length to Beam Ratio: 8.00 : 1
   'Natural speed' for length: 24.30 kts
   Power going to wave formation at top speed: 56 %
   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:   18.00 %,  22.15 ft / 6.75 m,  20.51 ft / 6.25 m
      - Forward deck:   30.00 %,  20.51 ft / 6.25 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:      18.97 ft / 5.78 m
   Ship tends to be wet forward

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 104.0 %
      - Above water (accommodation/working, high = better): 164.5 %
   Waterplane Area: 30,710 Square feet or 2,853 Square metres
   Displacement factor (Displacement / loading): 116 %
   Structure weight / hull surface area: 128 lbs/sq ft or 625 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.97
      - Longitudinal: 1.28
      - Overall: 1.00
   Adequate machinery, storage, compartmentation space
   Excellent accommodation and workspace room
   Ship has slow, easy roll, a good, steady gun platform

25t - LR Wireless
25t - NF Devices
107t - 1918 FC

60t - Provision for 2 Armed Floatplane and Catapults on sides.