WesWorld

I'm unsure as to whether to go for the smaller 18,000 ton, 48 aircraft, 5 hull design; or the larger 22,000 ton 60 aircraft, 4 hull design.

Thoughts please?

Toledo, Iberia CV laid down 1928

Displacement:
18,146 t light; 18,667 t standard; 20,700 t normal; 22,327 t full load

Dimensions: Length overall / water x beam x draught
713.97 ft / 688.98 ft x 85.30 ft x 24.61 ft (normal load)
217.62 m / 210.00 m x 26.00 m x 7.50 m

Armament:
16 - 5.12" / 130 mm guns (8x2 guns), 67.03lbs / 30.41kg shells, 1928 Model
Breech loading guns in deck mounts with hoists
on side, all amidships, 2 raised mounts - superfiring
24 - 2.24" / 57.0 mm guns (12x2 guns), 5.65lbs / 2.56kg shells, 1928 Model
Breech loading guns in deck mounts
on side, evenly spread, 10 raised mounts
16 - 0.98" / 25.0 mm guns (8x2 guns), 0.48lbs / 0.22kg shells, 1928 Model
Breech loading guns in deck mounts
on side, all amidships, all raised mounts - superfiring
Weight of broadside 1,216 lbs / 551 kg
Shells per gun, main battery: 150

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 2.95" / 75 mm 364.17 ft / 111.00 m 11.09 ft / 3.38 m
Ends: Unarmoured
Upper: 0.98" / 25 mm 426.51 ft / 130.00 m 16.40 ft / 5.00 m
Main Belt covers 81 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 1.97" / 50 mm 0.98" / 25 mm -
2nd: 0.79" / 20 mm - -
3rd: 0.79" / 20 mm - -

- Armour deck: 3.94" / 100 mm, Conning tower: 1.97" / 50 mm

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 2 shafts, 99,252 shp / 74,042 Kw = 30.00 kts
Range 10,000nm at 15.00 kts
Bunker at max displacement = 3,661 tons

Complement:
862 - 1,121

Cost:
£4.564 million / $18.256 million

Distribution of weights at normal displacement:
Armament: 152 tons, 0.7 %
Armour: 3,803 tons, 18.4 %
- Belts: 822 tons, 4.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 94 tons, 0.5 %
- Armour Deck: 2,855 tons, 13.8 %
- Conning Tower: 32 tons, 0.2 %
Machinery: 3,090 tons, 14.9 %
Hull, fittings & equipment: 6,101 tons, 29.5 %
Fuel, ammunition & stores: 2,555 tons, 12.3 %
Miscellaneous weights: 5,000 tons, 24.2 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
25,116 lbs / 11,392 Kg = 374.7 x 5.1 " / 130 mm shells or 2.9 torpedoes
Stability (Unstable if below 1.00): 1.08
Metacentric height 4.6 ft / 1.4 m
Roll period: 16.7 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.08
Seaboat quality (Average = 1.00): 1.22

Hull form characteristics:
Hull has raised forecastle
Block coefficient: 0.501
Length to Beam Ratio: 8.08 : 1
'Natural speed' for length: 26.25 kts
Power going to wave formation at top speed: 52 %
Trim (Max stability = 0, Max steadiness = 100): 58
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 9.84 ft / 3.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 26.25 ft / 8.00 m
- Forecastle (30 %): 26.25 ft / 8.00 m (16.40 ft / 5.00 m aft of break)
- Mid (50 %): 16.40 ft / 5.00 m
- Quarterdeck (15 %): 16.40 ft / 5.00 m
- Stern: 16.40 ft / 5.00 m
- Average freeboard: 19.36 ft / 5.90 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 81.0 %
- Above water (accommodation/working, high = better): 142.1 %
Waterplane Area: 39,193 Square feet or 3,641 Square metres
Displacement factor (Displacement / loading): 128 %
Structure weight / hull surface area: 110 lbs/sq ft or 537 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.01
- Longitudinal: 1.00
- Overall: 1.00
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

48 aircraft carried, 24 attack & 24 fighters, type undecided.


Seville, Iberia CV laid down 1928

Displacement:
22,384 t light; 22,997 t standard; 25,300 t normal; 27,142 t full load

Dimensions: Length overall / water x beam x draught
751.96 ft / 721.78 ft x 91.86 ft x 26.25 ft (normal load)
229.20 m / 220.00 m x 28.00 m x 8.00 m

Armament:
16 - 5.12" / 130 mm guns (8x2 guns), 67.03lbs / 30.41kg shells, 1928 Model
Breech loading guns in deck mounts with hoists
on side, all amidships, all raised mounts - superfiring
24 - 2.24" / 57.0 mm guns (12x2 guns), 5.65lbs / 2.56kg shells, 1928 Model
Breech loading guns in deck mounts
on side, evenly spread, 10 raised mounts
16 - 0.98" / 25.0 mm guns (8x2 guns), 0.48lbs / 0.22kg shells, 1928 Model
Breech loading guns in deck mounts
on side, all amidships, all raised mounts - superfiring
Weight of broadside 1,216 lbs / 551 kg
Shells per gun, main battery: 150

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 3.94" / 100 mm 459.32 ft / 140.00 m 11.52 ft / 3.51 m
Ends: Unarmoured
Upper: 1.97" / 50 mm 459.32 ft / 140.00 m 16.40 ft / 5.00 m
Main Belt covers 98 % of normal length

- Torpedo Bulkhead:
0.98" / 25 mm 459.32 ft / 140.00 m 24.08 ft / 7.34 m

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 2.95" / 75 mm 1.18" / 30 mm -
2nd: 0.79" / 20 mm - -
3rd: 0.79" / 20 mm - -

- Armour deck: 3.94" / 100 mm, Conning tower: 1.97" / 50 mm

Machinery:
Oil fired boilers, steam turbines,
Electric motors, 2 shafts, 111,204 shp / 82,958 Kw = 30.00 kts
Range 10,000nm at 15.00 kts
Bunker at max displacement = 4,145 tons

Complement:
1,002 - 1,303

Cost:
£5.329 million / $21.318 million

Distribution of weights at normal displacement:
Armament: 152 tons, 0.6 %
Armour: 5,326 tons, 21.1 %
- Belts: 1,524 tons, 6.0 %
- Torpedo bulkhead: 403 tons, 1.6 %
- Armament: 119 tons, 0.5 %
- Armour Deck: 3,244 tons, 12.8 %
- Conning Tower: 37 tons, 0.1 %
Machinery: 3,462 tons, 13.7 %
Hull, fittings & equipment: 7,244 tons, 28.6 %
Fuel, ammunition & stores: 2,916 tons, 11.5 %
Miscellaneous weights: 6,200 tons, 24.5 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
31,498 lbs / 14,287 Kg = 469.9 x 5.1 " / 130 mm shells or 4.9 torpedoes
Stability (Unstable if below 1.00): 1.09
Metacentric height 5.2 ft / 1.6 m
Roll period: 16.9 seconds
Steadiness - As gun platform (Average = 50 %): 70 %
- Recoil effect (Restricted arc if above 1.00): 0.07
Seaboat quality (Average = 1.00): 1.25

Hull form characteristics:
Hull has raised forecastle
Block coefficient: 0.509
Length to Beam Ratio: 7.86 : 1
'Natural speed' for length: 26.87 kts
Power going to wave formation at top speed: 51 %
Trim (Max stability = 0, Max steadiness = 100): 56
Bow angle (Positive = bow angles forward): 30.00 degrees
Stern overhang: 13.12 ft / 4.00 m
Freeboard (% = measuring location as a percentage of overall length):
- Stem: 29.53 ft / 9.00 m
- Forecastle (30 %): 29.53 ft / 9.00 m (16.40 ft / 5.00 m aft of break)
- Mid (50 %): 16.40 ft / 5.00 m
- Quarterdeck (15 %): 16.40 ft / 5.00 m
- Stern: 16.40 ft / 5.00 m
- Average freeboard: 20.34 ft / 6.20 m
Ship tends to be wet forward

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 97.7 %
- Above water (accommodation/working, high = better): 138.9 %
Waterplane Area: 44,535 Square feet or 4,137 Square metres
Displacement factor (Displacement / loading): 129 %
Structure weight / hull surface area: 116 lbs/sq ft or 567 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.01
- Longitudinal: 0.99
- Overall: 1.00
Hull space for machinery, storage, compartmentation is adequate
Room for accommodation and workspaces is excellent
Ship has slow, easy roll, a good, steady gun platform
Good seaboat, rides out heavy weather easily

60 aircraft carried, 36 attack & 24 fighters, type undecided

Build the bigger one.

I'm reading your miscelleanous weights differently. The first design's 5,000 t should get you 70 A/C. The second design's 6,200 t should get you around 78 A/C.

Knock that first CV's misc. weight down to the 3600 t you need for 60 A/C and you can probably add substantially to the armor.

Iberia's got a pretty expansive area to cover - the Americas, SE Asia, the Med. I'd recommend the five hull option for a bit more flexibility.

I thought it was 25 tons per aircraft!

25 t per aircraft up to 25 aircraft. Anything higher and it's the square of the number of aircraft in question.

Ahhhh, light dawns, they suddenly look a whole lot better as well!

You can thank me by deploying them all well away from the Indian Ocean.

I have to get to Macao and San Hainando somehow!

Give up your imperialistic ways and you can concentrate your flattops elsewhere...

...anyway - what's your thought on hull numbers? Opinion is split out here in the audience.

There are other options open as well.

Build 2x27,000ton carriers and 2x17,000ton carriers.

Or build loads of trade protection carriers to maximise deck area.

Quoted

Build 2x27,000ton carriers and 2x17,000ton carriers.

That was something I was thinking about when reading this post. Seeing how CG is looking at 5 18,000 tons hulls, he looks to be using all his 90,000 tons of carrier tonnage, so in that case, you're probably looking at 2x27,000 ton and 2x18,000 ton ships.

Maybe it's just me, but reading the following......

II.

No aircraft-carrier exceeding 22,000 tons (22352 metric tons)
standard displacement shall be acquired by, or constructed by, for,
or within the jurisdiction of, any of the Contracting Powers.


III.

Notwithstanding Part 3, Chapter B, Article II above, any of the
Contracting Powers may, provided that its total tonnage allowance of
aircraft carriers is not thereby exceeded, build not more than two
aircraft carriers, each of a tonnage of not more than 27,000 tons
(27,432 metric tons) standard displacement, and in order to effect
economy any of the Contracting Powers may use for this purpose any
two of their ships, whether completed or in course of construction,
which would otherwise be scrapped under the provisions of Part 3,
Chapter A, Article V above. The armament of any aircraft carriers
exceeding 22,000 tons (22,354 metric tons) standard displacement
shall be in accordance with the requirements of Part 3, Chapter B,
Article VII below.

...... this would imply that the 27,000 option is only for vessels rebuilt from something else that would have had to be scrapped at the time of the inception of the treaty.
So the biggest new build CV would be 22,000 tons!

18,000 tons should get you a nice carrier. The U.S. Yorktowns were 19,900 ton ships.

You need to built mulitple units. With a single unit you could find yourself without a CV when needed. 2 ships insures at least 1 might be available.
You are going to have to maintain carrier training (maybe a dedicated training CV). You need to have a reserve of carrier capable pilots above the basic manning levels of the CV's. (There is a definite quality in quantity)

Consider building fast auxiliaries that can be converted to light/escort carriers. (Look at the Japanese conversions of some of their tenders). This would get the hulls in the water but not impact your carrier tonnage limits (If the situation developed where you needed to convert these ships - you probably wouldn't be worrying about treaty limitations)

Who knows...what carriers lurk...in the hulls of merchantmen?

The Shadow knows...


XD

Quoted

...... this would imply that the 27,000 option is only for vessels rebuilt from something else that would have had to be scrapped at the time of the inception of the treaty.
So the biggest new build CV would be 22,000 tons!

No, 27,000 tons.

Quoted

Notwithstanding Part 3, Chapter B, Article II above, any of the
Contracting Powers may, provided that its total tonnage allowance of
aircraft carriers is not thereby exceeded, build not more than two
aircraft carriers, each of a tonnage of not more than 27,000 tons
(27,432 metric tons) standard displacement, and in order to effect
economy any of the Contracting Powers may use for this purpose any
two of their ships, whether completed or in course of construction,
which would otherwise be scrapped under the provisions of Part 3,
Chapter A, Article V above. The armament of any aircraft carriers
exceeding 22,000 tons (22,354 metric tons) standard displacement
shall be in accordance with the requirements of Part 3, Chapter B,
Article VII below.

May not must so you can build two 27,000 ton carriers without having to rebuild other ships.

Walter is right - at least that´s how Peng and I wanted the CT to be read back then....

Only Atlantis was allowed to build something much bigger (33kts).

Yes, but with a price though. Atlantis may have the biggest carrier afloat and be one of the most experienced carrier welding nations but at the cost of ranking 5th in reguards to capital ship numbers.

We all have to make sacrifices now and then. Maybe you can pull it straight in the years to come.

Quoted

Walter is right - at least that´s how Peng and I wanted the CT to be read back then....

Good thing I read that correctly. :-)

Personally I like the 2x27,000 ton and 2x18,000 ton option. I would use faster less armed/armored/capable 18,000 tons carriers (like the HIJMS Soryu and USS Sackets Harbor, though the latter one is <10,000 tons) and slower more armed/armored/capable 27,000 ton carriers (like the USS Ranger and USS Constellation)
Using a Sackets Harbor design, you might consider building 4x9,000 ton carriers and 2x27,000 ton carriers.