1920 Rules Changes (Final Draft)

[Guinness]

The following is the advanced almost ready for inclusion in the ruleset draft of the forthcoming 1920 rules revisions. Please post questions and comments here.

Summary of Changes:

1. Submarine rules clarified so that it is clearly understood that a submarine of the 1920 tech level or newer may carry any mix of mines and torpedoes at a 1-2 ratio. So a sub might for instance carry a total of 20 torpedoes and no mines, or a total of 40 mines and no torpedoes, or a total of 10 torpedoes and 20 mines, etc.

2. Current regime of buying individual aircraft and building aircraft tech specific bases is supplanted with a new system whereby aircraft are purchased in units similar to army units, and airfields/airbases persist similar to naval infrastructure. Full text of that is below.

The following would replace the aircraft rules found here: http://www.navalism.org/index.php?topic=278.msg28842#msg28842

Aircraft

Aircraft may be purchased in units as small as a squadron. The approximate manpower of each unit size can be found in the table below. In general terms, "small" is a single engine aircraft, "medium" is a twin engine aircraft, and "large" has 4 or more engines. The Moderators will be empowered to rule where a specific design fits in these classifications. Note that the manpower of air units is counted against per-nation military manpower caps (see army rules for details of these):

Num of Aircraft Manpower Unit Small Medium Large (Approx) Squadron 24 16 8 400 Wing 120 80 40 2000 Group 600 400 200 10,000

Aircraft unit acquisition costs in $ and BP are dependent upon the tech level of that unit, as are their maintenance costs. Aircraft units may not be upgraded from one tech level to the next. Rather, they may be scrapped, and if desired, their scrap value used for the acquisitions of new units of a newer tech level. The scrap value of an aircraft unit is:  0.15 * unit's original dollar/BP cost. The player earns back this value in the half-year following completion of scrapping.

Cost to construct air units:

Tech Level Squadron Wing Group $ BP $ BP $ BP 1906 0.10 0.02 0.50 0.10 2.50 0.50 1910 0.20 0.04 1.00 0.20 5.00 1.00 1913 0.30 0.06 1.50 0.30 7.50 1.50 1917 0.40 0.08 2.00 0.40 10.00 2.00 1921 0.50 0.10 2.50 0.50 12.50 2.50 1925 0.60 0.12 3.00 0.60 15.00 3.00 1929 0.70 0.14 3.50 0.70 17.50 3.50 1933 0.80 0.16 4.00 0.80 20.00 4.00 1937 0.90 0.18 4.50 0.90 22.50 4.50

Upkeep of air units:

Because aircraft are fragile and temperamental machines, it is not possible to maintain them at anything but wartime footing.

Tech Level Squadron Wing Group $ $ $ 1906 0.01 0.05 0.25 1910 0.02 0.10 0.50 1913 0.03 0.15 0.75 1917 0.04 0.20 1.00 1921 0.05 0.25 1.25 1925 0.06 0.30 1.50 1929 0.07 0.35 1.75 1933 0.08 0.40 2.00 1937 0.09 0.45 2.25

The fighting value of air units may be considered using the army unit artillery rating value according to this table:

Fighting strength of air units (in units equivalent to army artillery ratings):

Tech Level Squadron Wing Group 1906 0.02 0.1 0.5 1910 0.04 0.2 1 1913 0.06 0.3 1.5 1917 0.08 0.4 2 1921 0.10 0.5 2.5 1925 0.12 0.6 3 1929 0.16 0.8 4 1933 0.20 1 5 1937 0.24 1.2 6

Airfields
The Most basic airfield is simply an improvised strip, which may be constructed by the aircraft unit planning to use it. This has no cost, but these improvised fields have no permanent support capability. Units operating from these fields must have support from a permanent airfield for doing things like engine and airframe overhauls. Or in other words, while an improvised field can be constructed anywhere, to support a unit of aircraft more than one half-year, a permanent field must be available.

Airfields: Constr. Cost Type $ BP Permanent Support Capacity 0 1 0 Squadron 1 2 0.25 Wing 2 3 0.5 2 Wings 3 4 1 Group

Aircraft Unit/Airship Equivalency
Airships and aircraft may be based alongside one another. Airships still require additional fixed infrastructure (in the form of airship hangars). Existing airship bases are also convertible to type 0 airfields.

Airships are equivalent to aircraft unit size for the purpose of determining how many airships and aircraft may be supported by a given airfield according to this table:

Airship Type Equivalent Aircraft Unit 0 1/12 Squadron 1 1/6 Squadron 2 1/3 Squadron 3 1/2 Squadron 4 1 Squadron 5 2 Squadrons

Naval Aviation
Aircraft to be carried by or supported by ships are bought in units just as all other aircraft, and must be purchased separately from the ships they are planned to be operated from. Aircraft carried afloat do not require a shore base.

Transition from old Aircraft rules to new

Players for which it is convenient to reorganize their current aircraft into aircraft units according to these rules are encouraged to do so. Any new aircraft acquired in 1920 or after must be purchased according to these rules. Any aircraft purchased before 1920 are not required to be reorganized into units according to the new rules, nor are any existing facilities which support them.

For purposes of converting existing airfields to the new rules, players may total up the amount of BP used in construction of airfields up to 1920. This amount of BP may then be reallocated into post-rule change airfields.

For instance, if a player spent 1.5 BP total on 3 1913 tech airfields (ie 0.5BP x 3), and then 3 BP total on 3 1917 tech airfields (ie 1BP x 3), they will have spent a total of 4.5BP on airfields up to 1920. They may then reallocate that into 4.5BP of new airfields at their convenience. This might be 4 type 3 airfields and 1 type 2, or it might be 9 type 2's, etc. Most players will find this quite generous, and only a few will still need to build more than a few more airfields to accommodate their existing air forces.

Existing fields that only support Airships (ie locations that have airship hangars but no pre-1920 fixed wing aircraft facilities) automatically become type 0 airfields. This is to reflect the post-1920 requirement that airships be based at airfields. Airships continue to also require specialized hanger installations that must be purchases in addition to an airfield or airfields.

Also, when converting the old to the new unit system, players will be allowed to round up on a squadron basis. So if you have 20 twin engine aircraft, congratulations, you now have 2 squadrons, not 1.25 squadrons. This is strictly to make the conversion easier and to prevent players having to account for half squadrons. To build wings and groups past that, add up the number of squadrons that result.

[Nobody]

Transition from old Aircraft rules to new
...
For purposes of converting existing airfields to the new rules, players may total up the amount of BP used in construction of airfields up to 1920. This amount of BP may then be reallocated into post-rule change airfields.

For instance, if a player spent 1.5 BP total on 3 1913 tech airfields (ie 0.5BP x 3), and then 3 BP total on 3 1917 tech airfields (ie 1BP x 3), they will have spent a total of 4.5BP on airfields up to 1920. They may then reallocate that into 4.5BP of new airfields at their convenience. This might be 4 type 3 airfields and 1 type 2, or it might be 9 type 2's, etc. I think most players will find this quite generous, and that only a few will still need to build more than a few more airfields to accommodate their existing air forces.
...

Question: What happend to

Existing airfields are all convertible to type 0 airfields under the new rules. Existing airship bases are also convertible to type 0 airfields.

?
Especially the airship bit.


P.S.:
And something interesting: while converting from aircraft numbers to squadrons, I was surprised to find that while I got fractions of squadrons, their value, upkeep, manpower and artillery rating were integers (or very simple fractions). Now, after rounding up, I need floting points for them as well.

[Guinness]

Doh! Forgot the airship bit, so I put that back in. The rest is the result of convertibility discussion.

P.S.:
And something interesting: while converting from aircraft numbers to squadrons, I was surprised to find that while I got fractions of squadrons, their value, upkeep, manpower and artillery rating were integers (or very simple fractions). Now, after rounding up, I need floting points for them as well.

I'm a little curious about that as the result of rounding up should be a round number of squadrons. Maybe I misunderstand?

[Nobody]

Doh! Forgot the airship bit, so I put that back in. The rest is the result of convertibility discussion.

So Airfields are converted on BP cost, and hangars are converted just on the numbers (they are basically worth $1)?

And something interesting: while converting from aircraft numbers to squadrons, I was surprised to find that while I got fractions of squadrons, their value, upkeep, manpower and artillery rating were integers (or very simple fractions). Now, after rounding up, I need floting points for them as well.

I'm a little curious about that as the result of rounding up should be a round number of squadrons. Maybe I misunderstand?

Ah, no you see what I was trying to say was, that  e.g. Orange had 800 Fighters, which make up 33.333... squadrons which are worth exactly 10$ and 2 BP have an upkeep of 1$ and an artillery Rating of 2.
And after rounding up I now have 34 squadrons, worth 10.2$ and 2.04 BP with an upkeep of 1.02$ and an artillery rating of 2.04.

[Guinness]

So Airfields are converted on BP cost, and hangars are converted just on the numbers (they are basically worth $1)?

I've tried to clarify this above, but let me also expand on this issue:

One of the ideas with the new rules is that all flying thingies must be based at or at the very least supported by a dedicated base infrastructure. While aircraft can operate temporarily from forward bases, they cannot get the required amount of support there. Once we have flying thingy bases, we wanted to "normalize" all flying thingy basing requirements, hence the requirement that Airships have to be based at an airfield. The fairest way to handle that seems to be just to grant fields where only airships are operated Type 0 status.

Do note that the hangars for airships do not lose value this way, as hangars will still be required; they just need to be located at a type 0 airfield (at a minimum).

I suppose a player might feel like he's entitled to x number of type 0 airfields where x is the number of airship hangars he has. I can see that argument, but this is not the case here. Type 0 airfields are allocated by *location* where a hangar or hangars are located. If any player feels this unfairly penalizes them, please alert the mods via pm and we'll work it out.

[Desertfox]

I suppose a player might feel like he's entitled to x number of type 0 airfields where x is the number of airship hangars he has. I can see that argument, but this is not the case here. Type 0 airfields are allocated by *location* where a hangar or hangars are located. If any player feels this unfairly penalizes them, please alert the mods via pm and we'll work it out.

Maybe is say I have 3 hangars at a specific location that nets me not a Type 0 but say a Type 1? The argument could be made that more hangars mean better facilities hence higher level airfields.

It might just be me, but I would really prefer if aircraft units where on a base 5 or base 10 system. Makes tracking everything so much easier. So a squadron would have say 10 Heavy, 20 Medium, 40 Light (or 10-25-50). A wing being 3-4 squadron, a group 3-4 wings. Would also help with transition since all aircraft units have been either 25-50-100.

I brought this up a while back don't know if it was discussed. But I would like the option of spending a fixed amount on aircraft research whereupon I would automaticlly have the option to build aircraft of said year. Instead of the stepped method currently in place.

[Nobody]

I'm a bit surprised that there seems no difference in fighting power between a group of fighters and a group of bombers.

[Guinness]

Maybe is say I have 3 hangars at a specific location that nets me not a Type 0 but say a Type 1? The argument could be made that more hangars mean better facilities hence higher level airfields.

That argument could be made, but it is not one with which the mods agree. :)

It might just be me, but I would really prefer if aircraft units where on a base 5 or base 10 system. Makes tracking everything so much easier. So a squadron would have say 10 Heavy, 20 Medium, 40 Light (or 10-25-50). A wing being 3-4 squadron, a group 3-4 wings. Would also help with transition since all aircraft units have been either 25-50-100.

I did consider this before, but kept it the way it is. The major problem was manpower numbers, etc. At any rate, in my mind the actual number of planes in each unit matters very little if at all, as in the post 1920 aircraft rules it will not be individual aircraft combat being simmed, but unit combat. In that regard, it matters not whether you have 5 planes in a squadron or 50, what matters is the relative fighting strength.

I brought this up a while back don't know if it was discussed. But I would like the option of spending a fixed amount on aircraft research whereupon I would automaticlly have the option to build aircraft of said year. Instead of the stepped method currently in place.

This is not an idea we're prepared to implement at this time, mostly because it's inconsistent with all of our other tech.

I'm a bit surprised that there seems no difference in fighting power between a group of fighters and a group of bombers.

We aren't differentiating between units by specialty at this point. Partially, this is accounted for by the number of aircraft in each unit: there are many more single engine planes than 4 engine planes in a squadron. So the total payload of that squadron, at least in weight lifted, may even out. What probably won't is the range with that payload.

This is a place where we have to balance "realism" with complexity. And even if I had a table by specialty, how do I deal with mixed formations? One thing we're trying to avoid with huge and growing air forces is having to account for combat on a plane by plane, or even squadron by squadron basis.

All that written, there's nothing to prevent the wargamer in a given situation calculating in that a pure bomber formation has longer legs and better bomb loads than a pure fighter formation, or that a fighter formation if it encounters the bombers would eat the bombers for lunch. So really, that table of relative fighting strength should be understood for what it is: a point of comparison between aircraft of different tech levels, and between aircraft in a formation optimized for ground attack and the army units they might be attacking.

[Desertfox]

That argument could be made, but it is not one with which the mods agree.

Checked some numbers, I am the only affected because I'm the only one with Type 3s, but... I have 5 Type 3 hangars at Lake Constance. That is 10 Type 3 airships. A Type 0 airfield can only support 2 Type 3 airships... I'm going to have to ask for at least a Type 2 airfield at Lake Constance considering its a major facility, and a Type 1 at Sydney. Otherwise I won't even be able to support the airships I have there already.

I did consider this before, but kept it the way it is. The major problem was manpower numbers, etc. At any rate, in my mind the actual number of planes in each unit matters very little if at all, as in the post 1920 aircraft rules it will not be individual aircraft combat being simmed, but unit combat. In that regard, it matters not whether you have 5 planes in a squadron or 50, what matters is the relative fighting strength.

True, I just figured it would make it easier for us to change over to the new rules, since the old ones where on a base 5 system.

This is not an idea we're prepared to implement at this time, mostly because it's inconsistent with all of our other tech.

I did suggest it for ship engines too, untill that tech was removed. The aircraft tech is the only one currently based on escalating dates. I checked the numbers and it would not give anyone an unfair advantage. I just dislike the jerky aircraft progression, jumping 4 years every time doesn't allow for nice storylines.

[Sachmle]

As to the fighter/bombers having the same 'fighting power', perhaps a simple Attack vs format, such as Attack vs Planes and Attack vs Ground. Or maybe an offensive/defensive set? Sorta like what we have for Army units w/ the firepower/artillery ratings.

Fighters could be:
1906 0.5/0                         
1910 1/0
1913 1.5/0
1917 2/0.5
1921 2.5/1
1925 3/1.5
1929 4/1.5
1933 5/2
1937 6/2.5

Bombers could be:
1906 0/0.5
1910 0/1
1913 0/1.5
1917 0.5/2
1921 1/2.5
1925 1.5/3
1929 1.5/4
1933 2/5
1937 2.5/6

[Laertes]

I can't think of what a "defense" stat would represent. Agility? Meaningful in a turn-by-turn sim, but not in a more abstracted one. On a bomber, f'rinstance, if you dodge a fighter's attack it just means it has to come around for another attack run, giving you more time to shoot it down. It doesn't lead to a result of "he attacked, but you defended, so then he just went home in disgust." That can be abstracted into "attack vs fighters".

What about having "attack vs X" and "survivability" ratings? Some planes - the Lancaster heavy bomber, for instance - were renowned for being able to lose a fight and still make it back in recoverable condition. Others, especially high-performance fighters, weren't. It makes pushing the engineering envelope something other than a no-brainer - many excellent planes were built with almost-obsolete technologies in order to make them easy to keep going.

[Sachmle]

A 'defense' stat would represent the bombers ability to return fire/take damage.

[Nobody]

If I had to choose two names to differentiate plane abilities I would probably name them something like "air-power" and "bombardment". When for example ordering a bomber sortie their loss-rate would be determined by the by the air-power balance, meaning "own air-power" divided by "foreign air-power" in that area. And one would have to choose whether their own fighter are supposed ones own sky or their enemy's in order to either defend themselves against being bomb or bomb their enemy.

[ctwaterman]

Well I was going to write a few stories about a certain Italian General one I had in Charge of operation in New Zion.  He is famous because in OTL he wrote the first books on Strategic Airpower and going after strategic targets.

Unfortunately for the world We have not had a World War I and we have not had cities and railroad yards and Zepplin hangers bombed from the Air... I tried to Bomb New Zions Zepplin sheds because denying them naval reconisannce would have been a good thing.... ::)

But anyway we will not have to worry to much about Bombardment of cities and factories from the air anytime soon... well maybe 20 Half years.....

[Laertes]

A 'defense' stat would represent the bombers ability to return fire/take damage.

It doesn't sound functionally different from "attack vs planes". The ability to take damage would allow you to stick in a fight a little longer, but unless that little longer is used to kill the other guy, all you're doing is delaying the inevitable. Bomber formations cannot meaningfully 'disengage' from fighters; unless the fighter pilots feel an attack against a bomber flight is suicide, they'll just keep attacking. (Could be represented pretty easily with a roll of pilot morale + plane attack on each side, representing the courage of the fighters versus the discipline of the bombers.)

If I had to choose two names to differentiate plane abilities I would probably name them something like "air-power" and "bombardment". When for example ordering a bomber sortie their loss-rate would be determined by the by the air-power balance, meaning "own air-power" divided by "foreign air-power" in that area. And one would have to choose whether their own fighter are supposed ones own sky or their enemy's in order to either defend themselves against being bomb or bomb their enemy.

That's actually a very nice system. Very abstract, very nice.