Random thoughts on future techs

[The Rock Doctor]

Naval Artillery:

-Fuzed AA stuff is covered elsewhere under the planes tech.
-We're pretty much at the historical limit of what capital ship artillery can do
-Maybe we need a slot for automatic guns in the 6-8" range

Naval Propulsion:

-Don't see any obvious gaps.  Too soon for nukes.

Capital Ship Architecture:

-Transom sterns become a thing at some point, and we should find a place to slot them in.  Maybe this is the place, maybe not.

CV Architecture

-Cruiser hull strength for small CV for 1932 or onward?
-The sim isn't going to get to angled decks

Cruiser

-If we don't do automatic cruiser guns as part of naval artillery, we could do it here.
-Don't see any other needs here.  Don't see a need to let larger cruisers have 0.9 HS

DD/TB/MTB

-Don't see anywhere else to go except incremental progression of the MTB chart.

Mines:

-Assume we want more reliable magnetic mines
-Not sure if captive torpedo mines are a thing in our timescale.

Nightfighting and remore sensing:

-Looks fully worked out.

Range Finding:

-No idea.  An additional range increment is theoretically possible I guess.

Torpedos:

-Is full up aleady.

Subs: 

-Is full up.
-We might want to decide if there's a need to pay for designing stuff like Hedgehog or Squid.  I'd prefer not to bother.

Land: 

-Is full to the end of the sim.

Planes:

-Is covered to the end of the sim.

Amphib:

-Well decks should show up at some point, unless they're implied to existing in 1928 by the reference to amphibious vehicles.
-Helicopter assault unlikely in our timeframe.

Logistics:

-Arcane enough I don't think we need to sweat anything.

Mechanization:

-Is fine till end of sim.

Signals/Intel

-Probably room for another increment or two if we feel it's needed.  I don't.

[Kaiser Kirk]

oh this is frustrating.
Last night late
I wrote up a reply to Rocky and sketched out my thoughts

....and again lost the post to the time out, have to double hit post. 
Edit : Seems like a quick post like this, it posts when I hit post. Longer more thought out and involved... it's more of a double process.

I will try again later but everyone is welcome to chime in.

[The Rock Doctor]

I often get time-out messages but I don't lose the message, I just have to tell it to post again.

[Kaiser Kirk]

I must be thinking the post took and logging off without noticing the timeout and need to repost.
On the bright side- only happens on long posts.
On the not-so-bright side- that conditions me to think hitting 'post' works, and I can leave....
AND that means the ones I spend time on are the ones lost..

[Kaiser Kirk]

Naval Artillery

Yep, when we updated some techs in 1912, I tried to carry some techs forward, so the AA fuses are there.

My concern is the ME caps - as written- are low.

The USN 16/50 with 2700lb shell, in our system winds up with a MV about 653 (as I recall) instead of 739mps.

Plus, there's the 1935 RN estimates, and then the 1942 USN Estimates.
Meanwhile the USN put out a series of good shell in the 1930s.

So I'm thinking there is a spot for a mid 1930s Naval Artillery which gives a ME boost over the chart, and better shells. '+25% shell weight, superior Armor piercing.


Naval Propulsion.
Agreed.

Only thing I have thought of is 'advanced engines' to mimic the USN's superheated steamplants,
by being a couple years more advanced than laydown.
But it's not *required*.

I do want to edit one existing one to allow <=2000shp Diesels.
Irrelevant now, but the issue Irked DesertFox as he correctly knew they existed and our ruleset didn't allow them.


Capital Ships
Both Transom and bulbous bow are probably on the list.
I have read ...somewhere...about Transoms and introduction. We may be past it.

CV Architecture
This was the part that I wish I didn't loose.
So pretend this makes a great deal more sense...

The first question is...what is the goal of a 0.9 hull on carriers ?
Just the recognition that they didn't need to take the shock or damage of a battleship?
Or are we trying to make certain designs viable that are not at 1.0 ?

My impression is the progression was generally the Conversions, the 1st keel-up, then first fleet and then light carriers.

Ships like Ryujo break that, but I distrust statistics about IJN vessels.
Many had to be brought back and modified and strengthened, they ran trials before completion, so speeds are higher than real, and they deliberately deceived about capabilities and tonnage.

So to me the case for a lighter carrier comes with Wasp, or the British Light Fleet Carriers or the US Saipan and the like.

Wasp was laid down in 1936, so 1934 would be the earliest Tech date. But Wasp was more a cut-down Yorktown. So perhaps a 1940 date to allow the 1942 Light Fleet Carriers?


Actually I think angled decks were considered in the 1940s. But not sure how we'd model that anyhow.

Lastly, I would like to revist the waterplane area needed by 1934 onward airgroups.

Cruiser
The autoloading gun can be worked into the Naval artillery.
I have US Naval Weapons and USN Cruisers by friedman, so should be able to find the correct date.

I view the 0.9 as being the lighter engines and scantlings.
The 0.75 is ...I think, meant to follow Arethusa which replaced hull plating with homogeneous armor plates formed in the same shapes. I believe there were technical issues with doing that on thicker plates, and definitely on facehardened. Anyhow, that would be hard to SIM, but is my guess as to why we have that 0.75 category.

I do think another cruiser tech level is needed.

The New Orleans and Brooklyns all sported full turrets (lightened), but had the lighter machinery, scantlings, etc of cruisers. I think a number of the British Cruisers did too.

So I think a tech level that increases the 0.9 and 0.75 up, and allows turrets is I think needed.


DD/TB/MTB
Agreed.

Kinda.

The chart lists a "K" type of MTB...but the tech doesn't have them listed.

I very much want an S-26 type E-Boat, but the K-class doesn't look like that.
And the British 'Steam Gun Boat' does not fit either.

I'd like to try simming some small combatants and find out if they work in SS or if we need to chart them.

I'd also like to have some reference material, but I lack it.

Mines

I suppose we could do magnetic mines.

The USN seems to have explored and then dropped them with the Mk1o, and then
actually deployed some magnetic Mk12 "right before the war" to Manilla.

Air dropped are covered under the air tech- the type dropped would be by the mine tech.
Torpedo-launching mines- I think you are correct it's after our time.

Night fighting
Agreed

Fire Control
Looking at the 16/50 in Navweaps, they have a chart for accuracy.
At 30,000 yards, an Iowa class with top spot (so SDN to SDN mast tops, no shell splash spot) expected a 2.7% hate rate vs broadside.

Which means for a full broadside there was a 24% chance of a hit.
of course for a Vazrya would have a 44% chance of a hit :)

That actually suggests 30,000 is slightly beyond the effective FC range,
but we have that in the game anyhow.

What about RPC and mount stabilization? 
Not sure how to account for them, but they seem like a FC or Naval Art tech.

Torpedoes

Agreed

Subs

I think for Hedgehog and Squid, the thing to do is find a comparable mounting
and require it be researched like a new gun type.

Hedgehog with 6 sets of ammo was 28,720lbs.
About 1946 a trainable, stabilized version, slightly lighter.

Land:

Agreed.
There's a modifier for having better Army tech,
helped the Mayans vs. the IJA as I recall.

Planes:

Agreed.

The tech tree works.
I remain unhappy that Air Units are generic mixed-type Legions.


Amphib:

I am open to Well Decks.
I am also open to suggestion on how/when to do them.

AutoGyros would be about, but incapable of aerial assault :)
 
I would actually like to go back adjust the amount of DPs usable, perhaps a cap.
With another level raising it.

Currently, based on the rough unit size I'm using for Land units, Parthia could if it stripped all it's deployment forces, theoretically launch an invasion of about 1.2million troops.
That is the size of Operation Olympic - the planned invasion of Japan.
I would need more deployment points to manage Operation Coronet - 1.7million.
But the concept that in 1930ish I can manage what the US could at the END of WW2..seems off.

Logistics:
Agreed.

I had worked up a land combat draft which used Logistics level to govern how deep the invasion could push from your supply points. It was meant to make a logical stopping spot for continental war.

Mechanization:

Agreed.

The pre-game choice to de-emphasis Land and Air combat effects this.
I give a bonus for higher mech levels, which helped the Mayans vs. the IJA.

I still like K-World's unit design, but the choice to go with "Land Units" means there will be
no separate Armored divisions running around. At best armored forces are attached in smaller units to Infantry formations.

Signals/Intel

All I can think is possibly a level for Jamming and RDF ?

The Ship Design thread needs updating as default radio ranges have increased greatly.
Ironically, that still depends on high masts for aerials, something the IJN subs
lacked and so had difficulty serving as pickets, though they still did some good.


....ok lets see if I can *not* loose this posting it...
[/b]

[TacCovert4]

My thoughts:

Automatic Guns up to 6in - 1935 Cruiser Tech
Automatic Guns up to 8in - 1940 Cruiser Tech

Small Transom Stern - Probably a DD Tech first, Historically there were Transom Sterns on interwar DDs, I think a 1930 DD Tech allowing small transoms makes sense and allows for more historically accurate DDs (IE the speed delta improvement).


CV Tech - Cruiser Hull Strength Rules makes sense and allows for more accurate CVEs and some CVLs.  Maybe one denoting 'Night Operations' as well for a 1940 Tech?

I'm also good with revisiting waterplane area, maybe have a note for advanced deck parking to get the sort of big air groups the USN was putting on carriers later on......with the caveat that large deck parks don't work well in certain environments and are a detriment to survivability.

Amphib - well decks ok

Land - Eh, maybe, we can revisit, same with Mech.

Signals - Probably one for advanced coding machines, Enigma, and such. 

For NF we could include RDF and such as that's more built into tactical locating of enemies.

[Kaiser Kirk]

I am slowly trying to track down reasonable tech dates for various things.

Bulbous Bow - No effect in our SS. Taylor's towing tests found ram bows reduced resistance and he developed that into the first bulbous bow, introduced on the 1907 USS Delaware.  The modern Ini bow was introduced 1962, which works for a wider range. 
Both work for a range of Speed:length relationships, and more effective on broad U shaped hulls than V shaped, so better for merchants and capital ships.

US Cruisers indicate it was reintroduced for the 1929 cruiser discussions.

Transom - There's a discussion on NavWeaps..but nothing in my various books.
There was exploration of the Transom by the British in the early 1920s.
They fitted it to HMS Adventure, laid 1921, for propulsion reasons, but did not understand that the stern would drag the mines it laid behind it.

The Konigsberg class of 1927 has a clipped stern.
This raises the question of if a transom is as simple as clipping the stern, or if it needs a certain mathematical shape to work properly.

Then we skip ahead to the French Gloire and USS Brooklyn mentioned.

The first of the La Galissonniere class was essentially a 1932 ship.
Gloire's stern looks a bit like Konigsberg's. Long, slender and clipped.
Was that an effective Transom?  Perhaps Jefgte has sources on that.
Apparently they were the first to tow a mat behind to retrieve the floatplane.


USS Brooklyn's is the boxy 'transom'... but part of that was creating a space to hold the aircraft in the stern. I quickly read through the long design discussion in US Cruisers and do not see a mention. Nor in US Destroyers.

The first of the Brooklyn's were first laid 31 May 1934.

The Brooklyns mark the latest, the first real large boxy stern, and the start of a period where the stern shows up more. The discussion in US Cruisers focuses on the desire to move aviation from the amidships, where it was hard to recover in weather, to the stern, preferably in a hanger. So even here it could be questioned if the transom was a design or a side effect or both.

I think in this case they should be the benchmark.

Effectively a 1934.5 vessel but in N7 we would consider it a 1934 or 1935.
With a max-speed 2 year research time,
That would be a 1932 or 1933 research date.

Given that HY1 1932 is 'due' in 2 weeks, I suggest
Tech - 1933 Transom Stern be added to some field.

High Pressure Steam Engines
The discussion on Brooklyn had this information - the Brooklyn boilers had 40% more PSI than earlier. The later Clevelands had the same PSI, so this seems to be the introduction of these lighter more powerful plants.

Brooklyn : 700degrees/565psi
Older ships : 648/400psi
Cleveland : 850/565psi

I need to see if I can find weight:SHP to see if I can
find a way to emulate that advance.

Cruiser Hulls :
Brooklyn hull stresses 9.5-10 tons/psi, vs 8.9 for Quincy - a 6.7-12% increase in accepted stress between the two.

1942 – a note that hull weights reduced 18% since 1908 – better & more rational framing, welding, etc.

We also see the introduction of a lightened, but definite turret on cruiser hulls in this time period.

I think an early 1930s cruiser tech to allow for turrets on cruisers fits New Orleans, Brooklynn and Algerie for example.

I don't know if the light tonnages need to go higher, some SS's of those vessels might answer that question. The US Cruisers book probably has enough specifics- belt heights etc- to get close.
Though the Belt armor tapered, they don't say how fast..argh.

[Kaiser Kirk]

Still slowly trying to look up information to inform techs.
Haven't had a ton of browsing time to make it through the various books.

Cruiser Construction
There seems to be room for Two Techs here.


A) Increase in tonnage caps and allowance for turrets.
probably tied to the 1934 Brooklynn Class
""the light construction necessary to keep the prototype Brooklyn class within the 10,000 ton treaty limit has led to a greater number of lost bows than we expected""
...not a ringing endorsement, but

This also seems like the proper time to add the Transom.

1934-3 would be a 1931 Cruiser Tech ? Push to 1933 since we're past 1931 ?

B) Introduction of automatic guns 210mm (?) and less. This would be tied to US General Board decisions when they moved from development to approval in 1943.
If building ships with the tech is to be possible in 1943-4, then a research date 3 years prior is needed.
So 1940 Tech?

Engine Propulsion :
Not yet finding enough to justify another Tech

Looking at the SHP and machinery weights for 1930s US cruisers,
I am not seeing a shift in SHP:Wt that the extra PSI should cause.
However, the stats listed are 'Design' and switch from SHP to IHP.
Oddly the Pensacola class was designed for 60SHP/T, while the decade later
Brooklynns were designed for 55.8SHP/T...less.
However, I believe the earlier vessels didn't hit their designed speed.

In terms of hull strength,
""the light construction necessary to keep the protoype Brooklyn class within the 10,000 ton treaty limit has led to a greater number of lost bows than we expected"

Signals
So, radio ranges have to move up.
Found these tidbits.
1941 -iff transponder
1939 - HFDF – direction finding

on another topic :
Pg 125 mentions two 5" guns can provide illumination out to 20,000 yards.
I presume Starshell. The SKV standard is 12,000(?)yards from 3" guns.

[Kaiser Kirk]

I tried to sim the USS Brooklyn as close as possible.
It was unexpectedly difficult to sim the belt.
The belt is frequently cited as 5", but if you use that, comp hull is 0.9
If one does as I do, and use a magazine box to reinforce the belt/deck, then comp hull is 1.0


Conclusions
A) The Sim is quite close. But the notes on the ship indicates there's armor in places we don't really model, like on bulkheads. So there is missing weight.

B) The doubts about the belt complicate things.
The current design kinda works, but there are armor elements omitted I think. a
So likely a couple hundred more tons are needed, which would 'break' this below 1.0
So considering how we normally sim things, I can see an argument for 10,000@0.9 comp hull and 5000@0.75 comp hull as new break points

C) A transom is necessary to make this work.  The 'small transom' works SHP:Speed best. 

D) SS likely scaled off USN engine weights, as this works reasonably well and we do not need a new propulsion category.


Transom : The Design works well using the "Small Transom"

Light Ship should be 9456, inc 164t ballast, or 9292t
Standard was 9799.7,
normal 113799

This sim is
9792  light
10263 standard
11700 normal

*SHP is the nominal 100,000, not the 101 gained on trials.
Design speed was 32.5knts
111,000SHP is needed to get the 33.7 the ship got on trials,
but that is undoubtably light ship, so riding higher in the water for less draft.

[uArmor design is a little harder to figure out. [/u]
There's indication that the belt thickness was different adjacent to the magazines vs. adjacent to the machinery.
Machinery is 2".

US Cruisers says it is 1" less at the magazines than the New Orleans class. The New Orleans were 5.75" at the magazines, so Brooklyn should be 4.75".

This is the opposite of what navygeneralboard says which is 2" over magazines and 5" on machinery.
Which just doesn't make sense based on the description of New Orleans in US Cruisers.

A 2" belt and deck with a magazine box adding 2.75" would
bring it up to 4.75".

Deck armor
83t  2.75 magazine box
64t    1.5" deck forward of magazines
777t  2" deck

There is no 'excess' miscellaneous weight, I did make our N7 allowances. In 'real life' they often added weight and let the ship  sink deeper, indeed, the large bulges on older USN battleships were both for torpedo depth, but also to get the belt armor above water again.

USS Brooklyn, United states Cruiser laid down 1934

Displacement:
    9,792 t light; 10,263 t standard; 11,700 t normal; 12,849 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
    (607.74 ft / 600.00 ft) x 61.60 ft x (21.47 / 23.04 ft)
    (185.24 m / 182.88 m) x 18.78 m  x (6.54 / 7.02 m)

Armament:
      15 - 6.00" / 152 mm 47.0 cal guns - 112.35lbs / 50.96kg shells, 200 per gun
      Quick firing guns in turret on barbette mounts, 1934 Model
      5 x Triple mounts on centreline ends, majority forward
        2 raised mounts - superfiring
      8 - 5.00" / 127 mm 25.0 cal guns - 53.99lbs / 24.49kg shells, 200 per gun
      Anti-air guns in deck mounts, 1934 Model
      4 x Single mounts on sides, forward deck aft
      8 - 0.50" / 12.7 mm 90.0 cal guns - 0.07lbs / 0.03kg shells, 5,000 per gun
      Breech loading guns in deck mounts, 1934 Model
      8 x Single mounts on sides, evenly spread
        8 raised mounts
      Weight of broadside 2,118 lbs / 961 kg

Armour:
  - Belts:        Width (max)    Length (avg)        Height (avg)
    Main:    2.00" / 51 mm    390.00 ft / 118.87 m    9.50 ft / 2.90 m
    Ends:    Unarmoured
      Main Belt covers 100 % of normal length

  - Gun armour:    Face (max)    Other gunhouse (avg)    Barbette/hoist (max)
    Main:    6.50" / 165 mm    2.00" / 51 mm        5.50" / 140 mm
    2nd:    0.13" / 3 mm    0.13" / 3 mm              -
    3rd:    0.13" / 3 mm          -                  -

  - Armoured deck - single deck:
    For and Aft decks: 2.34" / 59 mm
    Forecastle: 1.50" / 38 mm  Quarter deck: 0.00" / 0 mm

  - Conning towers: Forward 5.00" / 127 mm, Aft 0.00" / 0 mm

Machinery:
    Oil fired boilers, steam turbines,
    Geared drive, 4 shafts, 95,697 shp / 71,390 Kw = 32.82 kts
    Range 5,350nm at 20.00 kts
    Bunker at max displacement = 2,586 tons

Complement:
    562 - 731

Cost:
    £4.452 million / $17.806 million

Distribution of weights at normal displacement:
    Armament: 447 tons, 3.8 %
      - Guns: 447 tons, 3.8 %
    Armour: 1,926 tons, 16.5 %
      - Belts: 306 tons, 2.6 %
      - Armament: 591 tons, 5.1 %
      - Armour Deck: 974 tons, 8.3 %
      - Conning Tower: 56 tons, 0.5 %
    Machinery: 2,753 tons, 23.5 %
    Hull, fittings & equipment: 4,481 tons, 38.3 %
    Fuel, ammunition & stores: 1,908 tons, 16.3 %
    Miscellaneous weights: 185 tons, 1.6 %
      - On freeboard deck: 115 tons
      - Above deck: 70 tons

Overall survivability and seakeeping ability:
    Survivability (Non-critical penetrating hits needed to sink ship):
      16,241 lbs / 7,367 Kg = 150.4 x 6.0 " / 152 mm shells or 1.8 torpedoes
    Stability (Unstable if below 1.00): 1.13
    Metacentric height 3.0 ft / 0.9 m
    Roll period: 14.9 seconds
    Steadiness    - As gun platform (Average = 50 %): 51 %
            - Recoil effect (Restricted arc if above 1.00): 0.56
    Seaboat quality  (Average = 1.00): 1.20

Hull form characteristics:
    Hull has a flush deck,
      a straight bulbous bow and small transom stern
    Block coefficient (normal/deep): 0.516 / 0.528
    Length to Beam Ratio: 9.74 : 1
    'Natural speed' for length: 26.28 kts
    Power going to wave formation at top speed: 58 %
    Trim (Max stability = 0, Max steadiness = 100): 42
    Bow angle (Positive = bow angles forward): 16.00 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 %,  27.00 ft / 8.23 m,  24.50 ft / 7.47 m
      - Forward deck:    40.00 %,  24.50 ft / 7.47 m,  22.00 ft / 6.71 m
      - Aft deck:    25.00 %,  22.00 ft / 6.71 m,  20.53 ft / 6.26 m
      - Quarter deck:    15.00 %,  20.53 ft / 6.26 m,  20.53 ft / 6.26 m
      - Average freeboard:        22.80 ft / 6.95 m

Ship space, strength and comments:
    Space    - Hull below water (magazines/engines, low = better): 91.8 %
        - Above water (accommodation/working, high = better): 195.1 %
    Waterplane Area: 25,596 Square feet or 2,378 Square metres
    Displacement factor (Displacement / loading): 126 %
    Structure weight / hull surface area: 109 lbs/sq ft or 532 Kg/sq metre
    Hull strength (Relative):
        - Cross-sectional: 0.93
        - Longitudinal: 1.81
        - Overall: 1.00
    Adequate machinery, storage, compartmentation space
    Excellent accommodation and workspace room
    Good seaboat, rides out heavy weather easily


misc
45t FC
25t LR radio

5t paravanes
80t 4x floatplanes
10t - 2x Catapults
20t - hanger in stern

[Kaiser Kirk]

I did this one seeking a smaller cruiser.
It was a 1940 springstyle done per Roosevelt's request, and had the warning that any real design would likely grow in weight.

The text discussion, it seems like the idea was building a cruiser to destroyer standards.

Interestingly, the SIM works on that basis, absolutely failing cruiser rules but meeting destroyers.

I can't help but think - Foxy would love it.

But I do view it as validating our destroyer comp hull, the engine tech, and the small transom.

Design 507, pg249, United states cruiser-destroyer laid down 1940

Displacement:
   3,842 t light; 4,050 t standard; 4,546 t normal; 4,943 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
   (460.00 ft / 460.00 ft) x 47.50 ft x (16.00 / 16.97 ft)
   (140.21 m / 140.21 m) x 14.48 m  x (4.88 / 5.17 m)

Armament:
      8 - 6.00" / 152 mm 47.0 cal guns - 130.07lbs / 59.00kg shells, 200 per gun
     Dual purpose guns in deck and hoist mounts, 1940 Model
     4 x 2-gun mounts on centreline ends, evenly spread
      2 raised mounts - superfiring
      8 - 0.50" / 12.7 mm 70.0 cal guns - 0.07lbs / 0.03kg shells, 5,000 per gun
     Machine guns in deck mounts, 1940 Model
     8 x Single mounts on sides, evenly spread
      8 raised mounts
      Weight of broadside 1,041 lbs / 472 kg

Armour:
   - Box over machinery & magazines:
   0.75" / 19 mm
   Forecastle: 0.75" / 19 mm  Quarter deck: 0.75" / 19 mm

   - Conning towers: Forward 0.75" / 19 mm, Aft 0.00" / 0 mm

Machinery:
   Oil fired boilers, steam turbines,
   Geared drive, 2 shafts, 75,278 shp / 56,157 Kw = 35.00 kts
   Range 6,500nm at 15.00 kts
   Bunker at max displacement = 893 tons

Complement:
   276 - 359

Cost:
   £3.007 million / $12.026 million

Distribution of weights at normal displacement:
   Armament: 266 tons, 5.9 %
      - Guns: 266 tons, 5.9 %
   Armour: 426 tons, 9.4 %
      - Armour Deck: 422 tons, 9.3 %
      - Conning Tower: 4 tons, 0.1 %
   Machinery: 1,984 tons, 43.6 %
   Hull, fittings & equipment: 1,125 tons, 24.8 %
   Fuel, ammunition & stores: 704 tons, 15.5 %
   Miscellaneous weights: 40 tons, 0.9 %
      - On freeboard deck: 77 tons
      - Above deck: 43 tons

Overall survivability and seakeeping ability:
   Survivability (Non-critical penetrating hits needed to sink ship):
     1,504 lbs / 682 Kg = 13.9 x 6.0 " / 152 mm shells or 0.5 torpedoes
   Stability (Unstable if below 1.00): 1.26
   Metacentric height 2.5 ft / 0.8 m
   Roll period: 12.6 seconds
   Steadiness   - As gun platform (Average = 50 %): 50 %
         - Recoil effect (Restricted arc if above 1.00): 0.66
   Seaboat quality  (Average = 1.00): 1.00

Hull form characteristics:
   Hull has a flush deck,
     a straight bulbous bow and small transom stern
   Block coefficient (normal/deep): 0.455 / 0.467
   Length to Beam Ratio: 9.68 : 1
   'Natural speed' for length: 23.12 kts
   Power going to wave formation at top speed: 66 %
   Trim (Max stability = 0, Max steadiness = 100): 50
   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 %,  24.00 ft / 7.32 m,  21.00 ft / 6.40 m
      - Forward deck:   30.00 %,  21.00 ft / 6.40 m,  19.00 ft / 5.79 m
      - Aft deck:   35.00 %,  19.00 ft / 5.79 m,  16.00 ft / 4.88 m
      - Quarter deck:   15.00 %,  16.00 ft / 4.88 m,  16.00 ft / 4.88 m
      - Average freeboard:      18.97 ft / 5.78 m

Ship space, strength and comments:
   Space   - Hull below water (magazines/engines, low = better): 160.0 %
      - Above water (accommodation/working, high = better): 184.4 %
   Waterplane Area: 14,323 Square feet or 1,331 Square metres
   Displacement factor (Displacement / loading): 85 %
   Structure weight / hull surface area: 50 lbs/sq ft or 244 Kg/sq metre
   Hull strength (Relative):
      - Cross-sectional: 0.50
      - Longitudinal: 1.54
      - Overall: 0.56
   Caution: Hull subject to strain in open-sea
   Cramped machinery, storage, compartmentation space
   Excellent accommodation and workspace room

Warning: Beam between bulkheads too wide

Design 507 was sketched out at the request of President Roosevelt.
The Std. Displacement and range is the same.

SHP is 278 off with a small transom.

The 6/47 has the standard shells per gun per nav weaps

The armor- should be 30lb /ft2 ,  1" = 40lb.
Likely not as compact as USN  with the 565psi plant.
And they were planning lightweight 'destroyer' machinery.

Put a -80t deduction in misc weight to make it balance per our destroyer rules.
That is equal to 2% light tonnage or 4% engine tonnage

The two floatplanes had no catapult in the design, or hanger.

misc
18t FC
25t LR radio
5t paravanes
40t 2x floatplanes
32   2TT4 21" 4T

[Kaiser Kirk]

On any 'light carrier' tech, or comp hull mod.
there seems to be 3 levels that need addressing.

Currently I am not at home, so my various books on carriers
are not available, which makes SS versions of them more difficult.
Try to find the waterline length of HMS Colossus..it's not so easy.

There is also the Deckspace/plane issue for monoplanes that needs addressing
before anyone has 1934 plane tech.

This is all verbal musing of where my thoughts are.
Discussion and new points are welcome, especially before I go to far in the wrong direction.

1.Merchants as flight platforms.
CAM - Catapult armed merchants, 1 use fighters - that could fit in the current rules
MAC - Flight decks on grain ships and oilers - again, a handful of fighter aircraft, I think it could fit in the current rules.

Conversions of Liner/Oiler/Other ... Snip was adamant he'd use his Mod Emeritus veto on this as a regular practice.  Any such thing will only be an in-major war contingency. 

For that my plan is to look up merchants of the period, and those will be 'stock hulls' available for conversion. Which will rather limit top speed, and thus full utility.


2. "Light Carriers' & Escort Carriers
Disregarding the IJN vessels...I doubt highly detailed information is available to make an evaluation

Escort Carriers apparently got started with HMS Audacity, but the USN had the 1939 Long Island class.

The 1942 Light Fleet Carrier (HMS Colossus) and the 1944 USS Saipan classes are probably the model here. However, USS Saipan actually belongs in Category 3.

A mark of all these is mercantile construction. In the case of the 1942 LFC, with additional internal subdivisions.
A mark of all these- Except USS Saipan- is a low speed.
A mark of all of these - Except USS Saipan - is no armor or TDS - Saipan had a 4" belt and 2.5" deck.

3. US Light Carriers, aka Cruiser Hull based 
The USS Independence and USS Saipan were both based on Cruiser hulls, the difference being
Independence was a light cruiser conversion on the ways, while Saipan was built from keel up
knowing it would be a carrier.


Thoughts
A) I see no reason carriers falling within cruiser tonnage limits would not be able to use cruiser hull comp hull. The hulls simply don't carry the stress factors of a battlewagon.
We see with the USS Brooklyn more sophisticated building, more welding, and higher stresses, all of which would be appropriate for a carrier.

We could tie this to the 1932 or 1938 carrier techs....
Or phrase a new Cruiser tech as 'All vessels under X tons, and with guns under Ymm can be Z comp hull'.

B) We could add to the 1938 carrier tech a 'mercantile construction' aspect.
Examples for Discussion :
A ship built to mercantile construction would be limited to their "'Natural speed' for length"
Due to costs, propulsion may not be Turbine or Electric. (Edit : maybe even require compound ?)
A ship built to mercantile construction would be limited to a L:B of 7:1 or less, and a BC of 0.55 or greater. (examples)
A ship built to mercantile construction would be limited to splinter armor of 25mm or less.
A ship built to mercantile construction would be limited to Excellent accomodation and machinery spaces
Same <2% weapons, but only for ship-mounted, none in excess of 210mm. Ships without aircraft can be made.
The ship may deduct from build Cost in $ and BP and time, 1/2 the tonnage of structure

So the sim of the 1942 I'm working on...
    Armament: 37 tons, 0.2 %
      - Guns: 37 tons, 0.2 %
    Machinery: 2,173 tons, 14.8 %
    Hull, fittings & equipment: 6,265 tons, 42.6 %
    Fuel, ammunition & stores: 2,402 tons, 16.3 %
    Miscellaneous weights: 3,840 tons, 26.1 %
      - On freeboard deck: 3,840 tons

This would allow  12314 light tons - (6265/2) = 9,181 tons.

It's more book-keeping, so violates Snips's KISS.
But the point of the mercantile builds was cheaper and faster.
And this is a 3 month time savings, and 1/4 price savings, making a more limited carrier more
attractive, if you want to field them in numbers...but for a peacetime build of a warfleet not very attractive

C) The Aviation ship Design rules had the basic assumption that folks would not be budgeting misc weight ahead because there was no way to know the future plane needs. Something we see in 'real world' carriers in many navies. Particularly of note is HMS Ark Royal, built by the nation with the most carrier experience, having it's airgroup downsized between design and in-service, as clear evidence that the growth in aircraft needs was not foreseen.

All that means, we probably should inflate the deckspace needed in line with the Misc weight increase.
The 1934 vs earlier is a 18.75% increase.

1.  Determine Maximum Air Group by Area

Using the "Waterplane area" in "Square meters" of the Hull Tab.

=waterplane /120 (seaplane carrier)

=waterplane/65 (1 hanger),  /77 for 1934 aircraft and later
 
(edit /l note for my sim of HMS Colossus, I got 79.1 , so quite close.  For that vessel the deck park increased space 15% from 41 to 48)

=waterplane/55 (2 hanger),  /65 for 1934 aircraft and later

[The Rock Doctor]

I agree that a CAM ship should fit in the existing rules.

I'd have thought that we'd just use existing auxiliary rules to fit in MAC ships. 

I'm not really sure about the mercantile carrier thing, reckoning that'd just be either an auxiliary or a regular carrier depending on how much miscellaneous weight was "armament".

I'm totally cool with the maximum airgroup area/waterplane proposal.

[Kaiser Kirk]

as is my habit, I will wait a day or so for others to chime in or further thoughts from Rocky  before responding.

Particularly when I'm wearing the 'mod hat' I am wary of responding too fast and so limiting discussion.

[Jefgte]

...1.Merchants as flight platforms.
CAM - Catapult armed merchants, 1 use fighters - that could fit in the current rules
MAC - Flight decks on grain ships and oilers - again, a handful of fighter aircraft, I think it could fit in the current rules...

"I think it could fit in the current rules"
I agree

...Conversions of Liner/Oiler/Other ... Snip was adamant he'd use his Mod Emeritus veto on this as a regular practice.  Any such thing will only be an in-major war contingency.

For that my plan is to look up merchants of the period, and those will be 'stock hulls' available for conversion. Which will rather limit top speed, and thus full utility...

Conversion of seaplane or other vessel carrier
should be able to be done. USS Langley - Béarn - HMS Argus - HMS Furious...

[The Rock Doctor]

I think there's no issue converting a carrier from a warship that was paid for as a warship (Bearn or Furious)

We'd build the original hulls of a Langley or an Argus as mercantile hulls (1/4 cost) and get a warship out of it - that would be the problem.