WesWorld

And here's a design for a training carrier for Germany.

Otto Lillienthal, German Training Carrier laid down 1933

Displacement:
8,040 t light; 8,224 t standard; 9,190 t normal; 9,963 t full load

Dimensions: Length overall / water x beam x draught
566.33 ft / 541.34 ft x 65.62 ft (Bulges 75.46 ft) x 16.40 ft (normal load)
172.62 m / 165.00 m x 20.00 m (Bulges 23.00 m) x 5.00 m

Armour:

- Conning tower: 3.94" / 100 mm

Machinery:
Oil fired boilers, steam turbines plus diesel motors,
Electric motors, 2 shafts, 15,484 shp / 11,551 Kw = 20.50 kts
Range 8,000nm at 15.00 kts
Bunker at max displacement = 1,739 tons

Complement:
469 - 610

Cost:
£1.629 million / $6.515 million

Distribution of weights at normal displacement:
Armament: 0 tons, 0.0 %
Armour: 37 tons, 0.4 %
- Belts: 0 tons, 0.0 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 0 tons, 0.0 %
- Armour Deck: 0 tons, 0.0 %
- Conning Tower: 37 tons, 0.4 %
Machinery: 451 tons, 4.9 %
Hull, fittings & equipment: 7,452 tons, 81.1 %
Fuel, ammunition & stores: 1,150 tons, 12.5 %
Miscellaneous weights: 100 tons, 1.1 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
78,565 lbs / 35,636 Kg = 727.4 x 6 " / 152 mm shells or 13.9 torpedoes
Stability (Unstable if below 1.00): 1.25
Metacentric height 4.0 ft / 1.2 m
Roll period: 15.9 seconds
Steadiness - As gun platform (Average = 50 %): 50 %
- Recoil effect (Restricted arc if above 1.00): 0.00
Seaboat quality (Average = 1.00): 2.00

Hull form characteristics:
Hull has a flush deck
Block coefficient: 0.480
Length to Beam Ratio: 7.17 : 1
'Natural speed' for length: 23.27 kts
Power going to wave formation at top speed: 37 %
Trim (Max stability = 0, Max steadiness = 100): 25
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 (20 %): 26.25 ft / 8.00 m
- Mid (50 %): 26.25 ft / 8.00 m
- Quarterdeck (15 %): 26.25 ft / 8.00 m
- Stern: 26.25 ft / 8.00 m
- Average freeboard: 26.25 ft / 8.00 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 19.0 %
- Above water (accommodation/working, high = better): 247.8 %
Waterplane Area: 23,246 Square feet or 2,160 Square metres
Displacement factor (Displacement / loading): 884 %
Structure weight / hull surface area: 181 lbs/sq ft or 885 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 1.88
- Longitudinal: 5.40
- Overall: 2.09
Hull space for machinery, storage, compartmentation is excellent
Room for accommodation and workspaces is excellent
Excellent seaboat, comfortable, rides out heavy weather easily

100 tons reserved for hangar space, workshops, and stores.

Built to merchantile standards?

Not really, just designed to fit within the Treaty rules for training carriers. She carries a lot of ballast to simulate additional engines, has more ventilation trunks than she needs for her designed engines, etc, to more closely simulate a real, if small, warship to give the designers and builders a better handle on this type of ship in case there's a need to build larger ones.

Quoted

Originally posted by Hrolf Hakonson
Not really, just designed to fit within the Treaty rules for training carriers. She carries a lot of ballast to simulate additional engines, has more ventilation trunks than she needs for her designed engines, etc, to more closely simulate a real, if small, warship to give the designers and builders a better handle on this type of ship in case there's a need to build larger ones.

Or be converted to one?

Quoted

Or be converted to one?

It's certainly a possibility, especially if the Treaty collapses.

Of course, just how much use a 8,000 ton carrier is..... well, remains to be seen. The US Sacketts Harbor experience says not too much, but who knows?

It's a fine line Germany's trying to walk here: if she builds a merchant-carrier, there's too many ways to cut corners that wouldn't be usable on a warship, so the experience isn't the best for learning how to build aircraft carriers. If she builds an actual warship, she's using up potentially valuable CT tonnage on a ship that's really an experiment, a trial piece. So ..... <shrug> you do the best you can.

Building a 'warship' carrier is risky for a first effort.
What other nations can provide you with background data on early carrier development - to save some steps in the process.
Many of the early carriers were conversions of combatants or merchant ships. It gave an operturnity understand the requirements of carrier operations prior to investing in a purpose built design.
You need to take 'baby steps" Not only are you concerned with the ship itself but with the aviation assets it will embark. The carrier & its aircraft are a package deal.

Germany thought about doing a merchant-conversion for it's training carrier, but decided against it on the grounds that that wouldn't give sufficient knowledge to the designers and constructors. If the "experimental carrier" clause of the CT was still active, Germany could have gone down the merchant-conversion route and still been able to replace it at will, but that clause doesn't allow for an experimental carrier to be built now.

As far as the airgroup goes, at least with a training carrier that's pretty easy: you're only allowed 2 planes aboard and under the deck. But that does give room to see what works and what doesn't, and how much space these things actually need.

Germany's getting assistance where it can. Delegations have toured Nordish, Atlantean, US, and Indian carriers, and probably one or more of those nations have been contacted for assistance in avoiding mistakes they've committed for this design.

This is what the ship would look like in it's warship form.

Otto Lillienthal, German Training Carrier laid down 1933

Displacement:
8,051 t light; 8,283 t standard; 9,190 t normal; 9,915 t full load

Dimensions: Length overall / water x beam x draught
570.12 ft / 541.34 ft x 65.62 ft (Bulges 75.46 ft) x 16.40 ft (normal load)
173.77 m / 165.00 m x 20.00 m (Bulges 23.00 m) x 5.00 m

Armament:
12 - 3.46" / 88.0 mm guns (6x2 guns), 20.79lbs / 9.43kg shells, 1933 Model
Anti-aircraft guns in deck mounts
on side ends, evenly spread, all raised mounts - superfiring
16 - 1.46" / 37.0 mm guns (8x2 guns), 1.55lbs / 0.70kg shells, 1933 Model
Anti-aircraft guns in deck mounts
on side, all amidships, all raised mounts - superfiring
Weight of broadside 274 lbs / 124 kg
Shells per gun, main battery: 300

Armour:
- Belts: Width (max) Length (avg) Height (avg)
Main: 1.97" / 50 mm 330.22 ft / 100.65 m 9.71 ft / 2.96 m
Ends: Unarmoured
Main Belt covers 94 % of normal length

- Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
Main: 0.79" / 20 mm 0.39" / 10 mm -
2nd: 0.79" / 20 mm 0.39" / 10 mm -

- Armour deck: 1.57" / 40 mm, Conning tower: 3.94" / 100 mm

Machinery:
Oil fired boilers, steam turbines plus diesel motors,
Electric motors, 2 shafts, 72,862 shp / 54,355 Kw = 32.00 kts
Range 8,000nm at 15.00 kts
Bunker at max displacement = 1,632 tons

Complement:
469 - 610

Cost:
£2.873 million / $11.493 million

Distribution of weights at normal displacement:
Armament: 34 tons, 0.4 %
Armour: 1,031 tons, 11.2 %
- Belts: 270 tons, 2.9 %
- Torpedo bulkhead: 0 tons, 0.0 %
- Armament: 20 tons, 0.2 %
- Armour Deck: 704 tons, 7.7 %
- Conning Tower: 37 tons, 0.4 %
Machinery: 2,123 tons, 23.1 %
Hull, fittings & equipment: 3,628 tons, 39.5 %
Fuel, ammunition & stores: 1,139 tons, 12.4 %
Miscellaneous weights: 1,234 tons, 13.4 %

Overall survivability and seakeeping ability:
Survivability (Non-critical penetrating hits needed to sink ship):
14,869 lbs / 6,744 Kg = 715.1 x 3.5 " / 88 mm shells or 2.0 torpedoes
Stability (Unstable if below 1.00): 1.21
Metacentric height 3.7 ft / 1.1 m
Roll period: 16.4 seconds
Steadiness - As gun platform (Average = 50 %): 71 %
- Recoil effect (Restricted arc if above 1.00): 0.03
Seaboat quality (Average = 1.00): 1.22

Hull form characteristics:
Hull has rise forward of midbreak
and transom stern
Block coefficient: 0.480
Length to Beam Ratio: 7.17 : 1
'Natural speed' for length: 27.38 kts
Power going to wave formation at top speed: 61 %
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: 32.81 ft / 10.00 m
- Forecastle (22 %): 29.53 ft / 9.00 m
- Mid (50 %): 26.25 ft / 8.00 m (19.69 ft / 6.00 m aft of break)
- Quarterdeck (17 %): 19.69 ft / 6.00 m
- Stern: 19.69 ft / 6.00 m
- Average freeboard: 24.44 ft / 7.45 m

Ship space, strength and comments:
Space - Hull below water (magazines/engines, low = better): 93.2 %
- Above water (accommodation/working, high = better): 230.1 %
Waterplane Area: 24,163 Square feet or 2,245 Square metres
Displacement factor (Displacement / loading): 135 %
Structure weight / hull surface area: 92 lbs/sq ft or 449 Kg/sq metre
Hull strength (Relative):
- Cross-sectional: 0.91
- Longitudinal: 2.18
- 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

Space for 32 aircraft, along with 4 spares at 25 tons each.

110 tons reserved for command spaces and growth.