Draft Carrier Rules

[Kaiser Kirk]

Sorry about the delay,
Weds are my night 'off' and I regularly do other stuff,
but I also slept badly and so by Thursday evening was exhausted
and just watched TV.

Now I'll work on the updated proposal.

[The Rock Doctor]

No worries. 

I've had two bad nights in a row due to "Restless Leg Syndrome," which is pretty annoying.

[Kaiser Kirk]

Ok, let's play "How badly has Kirk screwed this up"

This is the revamped version.

I used Rocky's revised presentation, as I presume that makes more sense than my usual dense Prose.

-Waterplane
I did a bunch of searching and put together a reasonable Sim of Enterprise.
In order to evaluate the American Carriers, I had to get a handle on how big the deck parks were.
From the commentary on Implacable, I'm thinking a deck park is roughly a ½ hanger.
Which would mean Enterprise could put 2/3rds of her airgroup in the single hanger.
...so I worked from there.

Anyhow, the /65 single hanger waterplane works decently for Enterprise's estimated hanger, and for Lexington. The Brits really seem to have been conservative with Ark Royal, while the Japanese built light with Shokaku, and the /55 is a comprimise of the two.

-Weight per plane:
So, working from sims mainly of Enterprise, Shokaku and Arc Royal, I came up with aircraft weights.

There seems to be about a 0.85 change in airgroup weight going from biplanes to monoplanes.

In the end, Both Shokaku and Enterprise have additional comp hull, at 1.18 and 1.12, but I'm guessing I'm missing  something... or planes should be 90t. 
It's probably ok- going back to Fox's 80% solution comment.

- Armor deck as flight deck : Since the time I did try it I found it a PITA.
I know Foxy doesn't like the + Freeboard, but I still don't get why.
I think Rocky's minimum freeboard works pretty well.


0.  What kind of ship is it?

"Carriers" include seaplane carriers, seaplane/flight deck "cruisers", and flight deck carriers.
Carrier : Has a flight deck. Deck at least extends from Stern to Foredeck -forward.

Seaplane Carrier : No flight deck, 7+ armed/unarmed aircraft on board, length irrelevant. Airgroup launched by catapult or from water, recovery on water.

Flight Deck/ Seaplane "Cruiser" : Partial length Hanger/Flight Deck.

-If it has 6 or less armed aircraft on board:  It's a warship or possibly aux (2% rule) but not a carrier.
-If it has 6 or less unarmed aircraft on board: It may be a warship or aux, but is not a carrier.
-If it qualifies as auxiliary, and has 6400t for for flying boat/seaplane tendering: Seaplane tender.

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)

=waterplane/55 (2 hanger)

For a Seaplane/Flight Deck Cruiser, use ½ the Maximum air group determined.

Note: When tech level allows "Deck park", iterations of deck parking will gradually increase maximum air group by up to 1/2 for single hanger, and 1/3 for double hanger.

2.  Miscellaneous Weight for Air Group:

- For planes prior to 1933 Airplane Tech : 80 tons/wheeled plane up to Air group maximum.
- For planes after 1933 Airplane Tech : 95 tons/wheeled plane up to Air group maximum.

- For single engine Seaplanes: 90 tons/plane up to Air group maximum.
- For multi-engine Seaplanes/flying boats : 110 tons/plane up to Air group maximum.

-Nations can allocate more miscellaneous weight if you want to allow for eventual deck parking/heavier aircraft/whatever.

- Example : A carrier built in 1927 with 90 biplane aircraft (7200 tons) will, after 1933 tech, field (7200/95) = 76 monoplane aircraft.

The 1946 aircraft tech will include the introduction of carrier jets.

Conversions
Conversions are inherently inefficient. Multiply required weights by 1.5.

3.  Determine minimum freeboard

Use the default "Length % of Lwl" setting.
The minimum freeboard depends on the type of vessel.

"Carriers"
This represents the Flight Deck and applies from "Quarter deck Freeboard-aft" to "Fore deck Freeboard-forward".   

This may be extended to cover the forecastle OR the forecastle may be left 5m (15ft) lower and serve as a "flying off deck", increasing take off rate.

As planes grow, they need more deck length to take off and land.

-Single, unarmored hangar :  9.0 m (30ft)

-Double, unarmored hangar OR single armored box hangar:  12.0 m (40ft)

-Double armored box hangar:  15.0 m (50ft)

Seaplane Carriers

-Seaplane Carrier : minimum of 9m (30ft) on just "Aft Deck and Foredeck"


  Flight Deck/Seaplane 'Cruisers'
These vessels are not restricted to the 'cruiser' architecture.

Flight deck/Seaplane cruiser (flight deck section only):
Conceptually, one end of the vessel has "Gun Battery Section" the other aviation facilities.
These vessels use "Aft Deck" or "Fore deck" area to represent the hanger.
The flight deck must be elevated to allow planes to clear the weapons

Designate the "Aft deck+Quarterdeck" or "Foredeck+Forecastle" as the "Hanger + Flight deck" area. Gun batteries may be placed on section not used as hanger.

A) Set Freeboard as desired.
B) For the chosen  "Hanger + Flight deck"
Add freeboard relative to the Gun battery section.

Example : IF Gun batteries on foredeck, freeboard 6m, then add the following heights for aft deck+quarter deck : 

-----minimum of +5.5m (18ft) As Single unarmored carrier (no superfiring main battery)
-----minimum of 11m (36ft)As Double unarmored carrier (superfiring main battery allowed)


4. Plane Operability and Sorties.
Historically, during WW2, torpedo bombers could not operate effectively on shorter flight decks, and escort carriers often had to catapult launch heavier aircraft, but were otherwise effective platforms.

Be advised the tonnage dedicated to aircraft fuel and munitions on interwar carriers, and such the wieght model here,  will be judged suffifient for 8 fully armed sorties. Fleet Train ships, or onboard "Extra" Misc. weight specified for Av-Gas or munitions can expand this.


5.  Armament:

Carrier / Seaplane carriers may not have centerline guns. The exception is a deck mount (or m&h) may be sited on centerline "fore deck forward" and/or "aft deck-aft".

-Hull casemates:  "Below deck"

-Sponson/side/casemate:  "On deck on sides"

-Guns on deck (e.g. Essex A/Y 5"):  "Superfiring on sides"

-Superfiring guns on deck (e.g. Essex B/X 5"):  "Double superfiring on sides"

-Flight deck/Seaplane cruisers: "Gun battery section" :  Up to three main battery turrets on centreline, no double-superfiring. Note that superfiring mounts affect flight deck freeboard, above.

6.  Armored Box Carrier:

-Use (actual thickness * 1.5) for ABC carrier decks

-Use upper belts (65% of hull length, 5.5m height per hangar deck) for hangar sides

-Make notes accordingly.

Make a note directly under the SS report's "Armour deck" line that the ship is an armored box carrier, and note the actual average thickness of the flight deck and hangar floor.
Note also the number of hangars.

7a. Non-Aircraft Carriers
For vessels embarking Six or fewer reconnaissance  Floatplane Aircraft. :
Set aside 20 tons per reconnaissance  Floatplane "On Deck".  Add 5 tons per catapult if desired. As lightweight reconnaissance  assets, These are effectively unarmed. 

If  armed float planes / single use catapult fighters : 25 tons per aircraft. Add 5 tons per catapult desired. These are considered "armanent".

7b. For Seaplane Tenders  :
Seaplane tenders are not assumed to have dedicated aircraft carried on board.  Rather they serve in a sheltered anchorage as a maritime basing and support for a "Air Point" and "deployment point" representing Flying Boats and or Maritime reconnaissance bombers, along with associated Floatplane fighters.

Assign as miscellaneous weight 6400t.  This covers crew quarters, spare parts, spare engines, weapons and fuel.

[snip]

The only thing that sticks out is a reversion to hard weight cutoffs for airgroups with the 1933 air tech. That's a sudden increase that does not pop up anywhere else. Why the abandonment of the sliding scale coupled with a fixed Tons-per-Plane?

[The Rock Doctor]

I'm fine with this proposal.

[Jefgte]

It also sounds good to me.

I am waiting to see all this condensed and formalized in "Rules".

[Kaiser Kirk]

Commentary : Had two thought this morning,
I don't think we settled on how to allocate the Misc Weight
1 location - upper hull
2 locations - hull under water + Upper hull
3 locations - hull under water + Upper hull, adn then "On deck" for deck parks.

I of course favor the most complex conceivable way... :)
From Foxys comments, he'd prefer the 1 location.
So...how about the rest of the gang?


Double Check Weight :
Opened the SS for Enterprise and did it for the single hanger + deckpark, suddenly comp hull was 1.01.
Then took another look at Shokaku, the issue there really seems to be the Japanese armor arrangement was more variable than SS allows.
They were 6.5" over magazines in a wierd box, and 4.1" over avgas. If you just average that as a single 4.1" deck, and manually shorten the belt to mag & mach, suddenly that's 1.01.
So, Wt =80 for biplanes works for those as well.  Looks like the Brits sacrificed some air ability for more protection weight wise.

The only thing that sticks out is a reversion to hard weight cutoffs for airgroups with the 1933 air tech. That's a sudden increase that does not pop up anywhere else. Why the abandonment of the sliding scale coupled with a fixed Tons-per-Plane?

Elegance.
All you have to do is divide the Air group wt by the wt/plane in one of two periods.
With the sliding scale you then needed another step tied to the exact tech tier.
I could see potential for adding an "Early Biplane" (65t) and we should add "Jet Age" (?) weight points

[The Rock Doctor]

Either above water or above water and under water.  The underwater component for munitions and avgas should be relatively small but having it down below might be helpful in offsetting topweight a bit.

The weight of actual deck-parked aircraft is relatively modest in comparison.

[Desertfox]

=waterplane/65 (1 hanger)

=waterplane/55 (2 hanger)

Does differentiating between one and two hangers really buy us much? I'd rather just combine the two and call it waterplane/60.

3.  Determine minimum freeboard

Use the default "Length % of Lwl" setting.
The minimum freeboard depends on the type of vessel.

With increased aircraft weights, I don't think we need this. But I can live with minimum freeboard heights compared to the original proposal. I do feel they are on the high side, may I suggest starting at 7m/23ft for single hangers? Give a bit more flexibility, after all we are not trying to exactly match OTL.

I prefer more than 6 aircraft for non-carriers, but I can live with it.

The only thing that sticks out is a reversion to hard weight cutoffs for airgroups with the 1933 air tech. That's a sudden increase that does not pop up anywhere else. Why the abandonment of the sliding scale coupled with a fixed Tons-per-Plane?

The jump in OTL was also very sharp and drastic. Also one jump is simpler than a sliding scale.

[snip]

The only thing that sticks out is a reversion to hard weight cutoffs for airgroups with the 1933 air tech. That's a sudden increase that does not pop up anywhere else. Why the abandonment of the sliding scale coupled with a fixed Tons-per-Plane?

The jump in OTL was also very sharp and drastic. Also one jump is simpler than a sliding scale.

I'd wager that the number of carriers that build to Pre-33 weight allocations are going to be few to none given there is only a limited window in which ships like that exist. Its not such a huge jump in weight so as to make it a cost not worth paying on every carrier.

[Kaiser Kirk]

On single vs. double hangers, the space a single hanger ship has without a deck park seems substantially lower.
While a giant like Lexington still has lots of AC, I think for smaller carriers, the option to instead have 2 hangers might be attractive for maximizing one's air group.

As for the weight jump, it really did seem tied to a drastic change in aircraft types.
That seems to be why air groups shrank.

There was another at the end of WWII, which I'll need to research
but falls in with MAC and other such things which are far enough away to defer.

Though this point made me think up a new wrinkle.
There need to be a "can not exceed" for airgroups, so they actually go down.
But Still allow bonus stores if folks want.
Sounds like a one line fix, I'll have to figure out how to simply explain and address it.

[Desertfox]

Though this point made me think up a new wrinkle.
There need to be a "can not exceed" for airgroups, so they actually go down.
But Still allow bonus stores if folks want.
Sounds like a one line fix, I'll have to figure out how to simply explain and address it.

Isn't that what the volume calculations are for?

[Kaiser Kirk]

Hmm, I think I was chasing my own tail.