Cruisers - Combined Arms

@Baron:

Maybe this A2 D2 unit combat values similarities could give an orientation for CWO Marc comments on historical Cruisers and Destroyers?
That would be fun if somehow history could provides some back up on this 2 hits Cruiser.  :-)

Regarding a unit’s hit rating, which in my mind reflects (in the case of a ship) resistance to battle damage offered by armour protection, torpedo bulkheads (if any), watertight compartmentalization, damage control abilities and so forth, a useful rule of thumb is that, in  very general terms, a balanced battleship or cruiser design was considered to be a design in which a ship’s armour protection was proportional to its own main armament.  In other words: a 16-inch-gun battleship ought to have adequate armour protection to allow it to stand up in a fight against another 16-inch-gun battleship.  “Stand up in a fight” does not mean immunity from damage; it means being well enough protected to fight the enemy on reasonably equal terms.  Likewise, an 8-inch cruiser ought to be adequately protected by its armour against 8-inch shellfire, and a 6-inch cruiser ought to be adequately protected by its armour against 6-inch shellfire.

This rule of thumb only applies to battleships and cruisers (and arguably only to battleships and cruisers of fairly orthodox design).  It doesn’t apply to carriers, most of which had little or no armour, and which in any case didn’t have heavy guns as their main armament.  It doesn’t apply to destroyers, which had no armour at all (hence heir “tin can” nickname).  And it doesn’t apply to battlecruisers, most of which had big guns but traded weak armour protection for increased speed (“eggshells armed with hammers”).  Some oddball battlecruisers even reversed the equation: the Scharnhorst class has 11-inch guns but were intended to be up-gunned to 15-inchers; their armour was under-strength relative to their never-fitted 15-inch guns, but over-strength relative to their 11-inch guns.

I think your old post should be added here for more historical details on Cruiser:
@CWO:

WWII cruisers can more accurately be divided into the following types:

• Battlecruisers.  These were basically cruisers that were the size of battleships, which carried heavy guns of the same caliber as battleships (though typically in smaller numbers), which were more lightly armoured than battleships, but which generally had higher speeds.  Hood (for which A&A 1941 provides a sculpt) is a clear-cut example of a battlecruiser; her 15-inch guns were actually larger than those of the more modern KGV class battleships, which carried 14-inchers.  Kongo (for which A&A 1941 provides a sculpt) was also a battlecruiser, though she was rebuilt and (arguably) reclassified as a battleship prior to WWII.  The Scharnhorst class ships were also battlecruisers, but with the interesting twist that they were over-armoured relative to their 11-inch guns (rather than under-armoured, which is usually the case with battlecruisers).

• Heavy cruisers.  As I mentioned, heavy cruisers were defined by the Washington Naval Treaty as any cruiser with guns larger than 6-inch caliber.  In practice, however, cruisers “with guns larger than 6-inch caliber” fell into two types (or three, if you count the above-mentioned battlecruiser type).  One type was the 8-inch gun cruiser, which was the most predominant type (to the point where “heavy cruiser” and “8-inch gun cruiser” were roughly synonymous).  The other – and much rarer – type involved cruisers which had guns larger than 8 inches but which were too small to be considered fully-fledged battlecruisers.  (I sometimes refer to such vessels as “ultra-heavy cruisers”, but this term wasn’t actually used during WWII.)   The Deutschland class Panzerschiffe fell into this category.  The Deutschlands were essentially ships which were the size of a heavy cruiser, which had the armour of a light cruiser, and which had the 11-inch guns of a low-end battleship.

• Light cruisers.  These were defined by the Washington Naval Treaty as any cruiser with guns of 6-inch caliber or less.  The term “light cruiser” was roughly synonymous with “6-inch cruiser”, which was the most common type.  A significant number of cruisers, however, were what I call “ultra-light cruisers” (a term which, like ultra-heavy cruisers, wasn’t actually used during WWII).  In many cases they were designed as 5-inch gun anti-aircraft platforms, like the British Dido class and the American Atlanta class.

From what you said, in this specific point:

It doesn’t apply to destroyers, which had no armour at all (hence heir “tin can” nickname).

It is clear that Cruiser can be able to endure much more damage than Destroyer.

For now, IMO the 2-hits Cruiser A2 D2 ShB2 C12 vs Destroyer A2 D2 C8 is acceptable from the historical perspective.
Not because of the same A/D value, but base on the Shore Bombardment capacity and heavier armour figured by the 2 hits.
Submarines get only 1 hit and are probably in the same category as the Destroyer when taking damage, because a hole in the hull make it useless for submersible operation.

In addition, the 2-Hits Cruiser gets the better hand in a face-to-face on the same IPCs basis against Destroyers.
2 2-hits Cruisers against 3 Destroyers:
Overall %*:   A. survives: 58.7%    D. survives: 37.2%    No one survives: 4.2%

About Subs, the game is still the same because Subs have First Strike against Cruiser. And, on offense, Subs are still better against them.
24 IPCs,
4 Subs against 2 2-hits Cruisers
Overall %*: A. survives: 79.2% D. survives: 20.8% No one survives: 0%

http://calc.axisandallies.org/?mustland=0&abortratio=0&saveunits=0&strafeunits=0&aInf=&aArt=&aArm=&aFig=&aBom=&aTra=&aSub=4&aDes=&aCru=&aCar=&aBat=&adBat=&dInf=&dArt=&dArm=&dFig=&dBom=&dTra=2&dSub=&dDes=&dCru=&dCar=2&dBat=&ddBat=&ool_att=Bat-Inf-Art-AArt-Arm-Sub-SSub-Des-Fig-JFig-Cru-Bom-HBom-Car-dBat-Tra&ool_def=Bat-Inf-Art-AArt-Arm-Bom-HBom-Sub-SSub-Tra-Des-Car-Cru-Fig-JFig-dBat&battle=Run&rounds=&reps=10000&luck=pure&ruleset=AA1942&territory=&round=1&pbem=

But, when Cruiser on offense against Subs, they will probably be as good as Destroyers.

@Young:

Based on everything I have read, I would take away the 2 hit advantage on Aircraft Carriers, but allow them to carry 3 air units to justify their 16 IPC cost, or if that’s to strong… give them a defense @1.

That will unbalance things.
If you want a more balance Carrier, just input 14 IPCs 1942.2 Carrier A1 D2 M2, 1 hit, 2 planes.
But Naval Base won’t be as useful for repair, since Carrier will be highest rate of IPCs/hit.
People will rather loose a Cruiser than Carrier.

Keep it OOB, it is fine.
The real issue with 2-hits Cruiser is the 4 times weaker Battleship in Naval Combat.
No one will pay such as 20 IPCs if you can get much combat value with a lesser investment.

Shore bombardment is not a decisive ability.

It is still less the case if you play OOB that: any Naval blocker forfeit the Shore bombardment in an Amphibious assault.

@Baron:

How Cruiser such Baltimore Class can be a match against Battleship?
Do you think a bunch of Heavy cruisers can outmatched a lesser number of Battleships?

As is true with a lot of things, the answer is “it depends”, so generalizations have to be treated with caution.  One-on-one, a (let’s say 16-inch) battleship would in principle be able to outfight a (let’s say) 8-inch cruiser, if the cruiser didn’t use its (often but not always superior) speed to simply run away.  16-inch guns have longer range than 8-inch guns, so if a battleship’s speed was equal or superior to that of a cruiser (which generally wasn’t the case), the battleship in principle would simply stay outside 8-in shellfire range but inside 16-inch shellfiure range and keep firing until the cruiser is sunk, while sustaining no damage to itself.  A cruiser, however, would usually have the speed advantage, so it would be up to the cruiser captain to decide whether he’d run or whether he’d fight.  If he chose to fight, he’d have to quickly close the distance to 8-inch shellfire range, but not get so close that he’d be within range of the battleship’s 5-inch dual-purpose guns, which would only make his situation worse.  His situation would already be bad enough: the cruiser’s 8-inch guns would heavily damage but would not sink a battleship armoured to resist 16-inch shellfire, but the battleship’s 16-inch guns would (in principle) make short work of a cruiser armoured to resist 8-inch shellfire.  Short of ramming the battleship outright (and I can actually picture some British captains being Nelsonian enough to do that if the mission was important enough), a single cruiser fighting a single battleship wouln’t have much chance of sending the battleship to the bottom.

The catch, of course, is that a one-on-one duel between a battleship and a cruiser is almost unimaginable.  Battleships usually don’t travel unescorted, for various reasons, not least of which is the fact that admirals don’t like the idea of a flotilla of enemy destroyers getting within torpedo range of a battleship.  One way to keep those fast and dangerous destroyers well away from your dreadnoughts is to intercept them with your own destroyers.  Destroyers started life precisely in that role, as “torpedo boat destroyers” (hence their name) because when the Whitehead torpedo was introduced in the late 19th century, surface-ship officers were horrified at the idea that a little torpedo boat could punch a hole – from a distance! – in the waterline of a cruiser or battleship.  (One Royal Navy officer of the time called these newfangled infernal machines “damned un-English” as an expression of his contempt.)  Also, as WWII progressed, battleships operated more and more as part of task groups or task forces, with ships of many types, so the prospect of a one-on-one duel with a cruiser was pretty close to zero.

@Baron:

But, when Cruiser on offense against Subs, they will probably be as good as Destroyers.

In real life, cruisers do not carry out offensives against subs.  They’re not equiped for it.  Subs, on the other hand, have no problem with sinking cruisers, as the crew of the General Belgrano found out during the Falklands War.

@CWO:

@Baron:

How Cruiser such Baltimore Class can be a match against Battleship?
Do you think a bunch of Heavy cruisers can outmatched a lesser number of Battleships?

As is true with a lot of things, the answer is “it depends”, so generalizations have to be treated with caution.  One-on-one, a (let’s say 16-inch) battleship would in principle be able to outfight a (let’s say) 8-inch cruiser, if the cruiser didn’t use its (often but not always superior) speed to simply run away.  16-inch guns have longer range than 8-inch guns, so if a battleship’s speed was equal or superior to that of a cruiser (which generally wasn’t the case), the battleship in principle would simply stay outside 8-in shellfire range but inside 16-inch shellfiure range and keep firing until the cruiser is sunk, while sustaining no damage to itself.  A cruiser, however, would usually have the speed advantage, so it would be up to the cruiser captain to decide whether he’d run or whether he’d fight.  If he chose to fight, he’d have to quickly close the distance to 8-inch shellfire range, but not get so close that he’d be within range of the battleship’s 5-inch dual-purpose guns, which would only make his situation worse.  His situation would already be bad enough: the cruiser’s 8-inch guns would heavily damage but would not sink a battleship armoured to resist 16-inch shellfire, but the battleship’s 16-inch guns would (in principle) make short work of a cruiser armoured to resist 8-inch shellfire.  Short of ramming the battleship outright (and I can actually picture some British captains being Nelsonian enough to do that if the mission was important enough), a single cruiser fighting a single battleship wouln’t have much chance of sending the battleship to the bottom.

The catch, of course, is that a one-on-one duel between a battleship and a cruiser is almost unimaginable.  Battleships usually don’t travel unescorted, for various reasons, not least of which is the fact that admirals don’t like the idea of a flotilla of enemy destroyers getting within torpedo range of a battleship.  One way to keep those fast and dangerous destroyers well away from your dreadnoughts is to intercept them with your own destroyers.  Destroyers started life precisely in that role, as “torpedo boat destroyers” (hence their name) because when the Whitehead torpedo was introduced in the late 19th century, surface-ship officers were horrified at the idea that a little torpedo boat could punch a hole – from a distance! – in the waterline of a cruiser or battleship.  (One Royal Navy officer of the time called these newfangled infernal machines “damned un-English” as an expression of his contempt.)  Also, as WWII progressed, battleships operated more and more as part of task groups or task forces, with ships of many types, so the prospect of a one-on-one duel with a cruiser was pretty close to zero.

Thanks for this detailed answer.

Since the Battleship have the bigger guns with the greater range and a consequent armour, this would satisfy a first-shot plunging fire extra-attack to help counter-weight the  Battlecalc real advantage of the 2-hits Cruiser.
So, all Battleship can make a First Shot Att/Def @4, immediately after Subs Surprise Strike phase, and before regular combat.
Any single hit unit casualty is immediately removed.

Just to tie up a loose end from earlier today before I go home, I did some checking and I don’t think the “destroyer leader” idea is really applicable to the concept of cruisers and destroyers working together as a combined-arms team.  Destroyer leaders (aka flotilla leaders) were simply large destroyers or small cruisers with some facilities aboard to house the officer who commanded a flotilla of destroyers – in other words, basically a ship with some extra office space.  This didn’t confer any combined arms advantage, any more than the presence of similar flagship facilities aboard larger ships conferred any combined arms advantages to admirals commanding task forces; what these offices really represent is the command-and-control system that exists in any naval formation consisting of more than one ship, so it’s nothing that would apply specifically (and only) to a cruiser+destroyer pairing.

simply no….

@Young:

Going back to the drawing board, if we reset attack and defense values back to oob rules… would increased shore bombardment capabilities alone be enough to boost Cruisers and Battleships as favorable purchases?

Shore Bombardments

Cruisers @3
Battleships @4

• Sea combat no longer negates bombardments during amphibious assaults
• All sea units that can bombard may do so regardless of how many units are landing
• Bombardments repeat every combat round during an amphibious assault

This one has some loopholes:
All sea units that can bombard may do so regardless of how many units are landing.

You cannot get rid of pairing with ground unit, otherwise their will be some Europe Dieppe straffing assault in which:
1 or 2 Infantries are scrapped while allowing many cruisers to drop the German’s stacks without any big retaliation.
German’s rolls can do overkill but there is only 1-2 Infantry lost.

Maximum, 1 Shore bombardment / unit making the debarkment.
This one must stay in your OOB rule, for sure.

I agree about returning on the drawing board.
Unfortunately 2-hits Cruiser A2 D2 C12, is still too much OP against costlier units such as Fg, TcB, StB, Carrier and Battleship.
Even a 10 IPCs 1-hit Cruiser A3 D3 M2, is much weaker.

About infinite Shore bombardment, I have no idea.
A 12 IPCs Cruiser will get the attack factor of a Fg at 10 IPCs.

In itself, not a problem.
It is more an issue from an historical depiction POV.

I think we have just demonstrated in the last few pages, how its basically impossible to fix the naval roster with just one unit in isolation, or by just using the combined arms or “special boost” type model.
:-D

@Young:

Based on everything I have read, I would take away the 2 hit advantage on Aircraft Carriers, but allow them to carry 3 air units to justify their 16 IPC cost, or if that’s to strong… give them a defense @1.

I see these as a workable solution, not least because of how frequently people in my playgroup gripe about the way damaged carriers are handled OOB. With fighters either getting trapped on deck, or unable to land on a stranded/damaged carrier. In a lot of cases the carriers end up being sunk or sacrificed anyway, and usually this just gets pushed out 1 round. I know we’ve discussed the 3 aircraft carrier in the past, and Baron offered a lot of ideas on why it might be preferable.

In general I adopt the view that YG had, looking more at how these units function as abstract game pieces, rather than historical analogs, but I still would like to strike a balance that serves the game from both perspectives.

On this last point, I think the attitude comes from a sense the the names of these pieces are sometimes arbitrary.

For example in the older games like Classic, destroyers and cruisers did not exist as a game piece. Though of course they existed in WW2! So if you’re a player like me, what you do is just imagine that the abilities of ships encompass the existence of other invisible units, representing them in the abstract. I think thats why I dont have an issue with things like warships transporting infantry, because I just imagine that the warship is escorting some invisible transport vessel not physically represented itself, but embodied by the warship that you can buy.

I could also imagine that say, we need yet another intermediate ship in A&A. And then people just adding in a new unit like “frigate”, or “light” or “heavy” or “battle” cruiser some random name,  just because it’s needed to fit the desired unit abilities. Some intermediate unit at the Attack/Def values, with a reasonable name to fit, since that’s basically what happened when cruisers and destroyers were introduced.

@Young:

Going back to the drawing board, if we reset attack and defense values back to oob rules… would increased shore bombardment capabilities alone be enough to boost Cruisers and Battleships as favorable purchases?

Shore Bombardments

Cruisers @3
Battleships @4

• Sea combat no longer negates bombardments during amphibious assaults
• All sea units that can bombard may do so regardless of how many units are landing
• Bombardments repeat every combat round during an amphibious assault

Bombardments repeat every round makes a lot of sense to me. Sea combat not negating bombardment is also interesting. But I know from previous experience designing tripleA games, that bombardment can be heavily abused if there is no restriction based on how many units offload. The prime example of this, was a common tactic where players purchased a big stack of bombardment capable warships and then used a single infantry unit on amphibious to bombard the hell out of coastal capitals at a relatively cheap cost. In a very extreme example, say you had a dozen cruisers that could all be activated by a lone amphibious inf unit, destroying on average 6 enemy infantry for a cost of just 1 attacking infantry lost. In Classic and Revised it wasn’t as bad, because only Battleships could bombard, they were very expensive, and the overall money in play wasn’t very high. But in a game like G40, where you can afford a lot more ships, the bombardment restriction based on how many ground are unloading is important. If going this route, I would keep the first line, and the last, but ditch the one in the middle.

As I was typing this out, I see Baron beat me to the punch on that last point.

Also, given what CWO has said about possible historical unit pairings, it doesn’t seem like there are many great options for a combined arms enhancement with cruisers. Just focusing on bombardment alone might be easier.

Many players in my group have also expressed a certain distaste for the the whole idea that units which are destroyed on bombardment get to return fire. I have to agree that this doesn’t make a whole lot of sense. If the desire is to just find a way to kill off attacking ground during an amphibious assault, perhaps this should be handled via a special roll? Based not on the defending units normal defense value, but rather just make it a simple roll, similar to aa guns, which determine how many attacking dudes get killed before they ever get off the beach?

Another idea I once had back in AA50 was to just detach bombardment from the amphibious assault. But in that case only allowing these ships to bombard at a reduced value. Hits at 1 for cruisers, 2 for battleships.  This was done because it seemed kind of silly how players would just throw away infantry on doomed amphibious invasions purely to do bombardments with their battleships or cruisers.

The idea here was that ships could bombard the coast at all times at the reduced values, but if bombarding in coordination an amphibious assault they hit at the OOB values.

This was open to abuse and exploitation, and that was the main problem, since you didn’t have to risk ground to make a hit. Even still, it felt somehow more fitting with the character of bombardment. Maybe if they had to roll 2d6 or 3d6 and added up the dice to meet some higher value to score a successful hit?Say cruisers bombard at 9 2d6 cumulative , battleships bombard at 12 3d6 cumulative. Something along those lines? Just typing it out it already sounds too onerous. How about instead of firing back against amphibious ground, the defender gets to fire back against the ship itself? Sort of like anti-air fire but with ships. Though bombardment capable ships are expensive so this roll would have to be restricted somehow, harder than aa gun fire to hit for the defender. But maybe, if the risk was to the ship rather than the ground, this would provide the requisite element of risk to the bombarding attacker, to prevent it being just a freebie, which is the only way I can see to make it work if you don’t pair the ship with a ground unit for bombardment, but instead want to separate the bombardment off into its own separate action.

I agree enhanced bombardment, whatever form it takes, is better than an Anti Air role for Cruisers and BB, since, if those ships got to make anti air shots in the opening round, it would totally screw the key battles in sz110 and sz 111 etc.

@Black_Elk:

I agree enhanced bombardment, whatever form it takes, is better than an Anti Air role for Cruisers and BB, since, if those ships got to make anti air shots in the opening round, it would totally screw the key battles in sz110 and sz 111 etc.

Not if it is only considered as a Combined Arms bonus abilities, as I introduced earlier, when all 3 units are together: Cruiser+Battleship+Carrier.
I insist on this to underlined that is the most historically accurate defensive formation.
SZ6 and SZ10 are out of reach in any initial assault.
And you get the same result if you prefer to give a pairing 1:1 Cruiser+Carrier or Battleship+Carrier.

So it is not for this reason that you can reject this idea, as such.

You can give more individual abilities to Cruiser and Battleship.
But I keep thinking that, from an historical perspective, AA Flak should be a Combined Arms, not a specific ability given to a single type unit.

@Baron:

As for the many special attributes that can be given to Cruisers that will enviably result in players purchasing more… there are a lot of variables that could automatically push them into the realm of overpowering. The largest variable to consider is the problem of giving Cruisers something that will completely alter how players view opening strategies. Although we all want Cruisers to be purchased more often, and have them be a vital part of our ultimate war effort, the truth is that there are many already on the board. Therefore, all idea’s of giving Cruisers AA capabilities will never fly with purists because their entire G1 strategy will be forever altered. The question is… how do we give newly purchased Cruisers a special attribute while neutralizing the ones in the setup?
**Cruisers attack @4 when paired with a Battleship.  **

The idea of not altering the opening strategies is a sound principles and should be taken into account for balance purpose.
I have this question, are you sure your combined arms bonus for Cruiser doesn’t fall into this trap?
Because, at first glance, there is much more opportunities than with AA flak combined with carriers:

Italy:
SZ 97: 1 transport, 1 cruiser, 1 battleship

Germany:
SZ 113: 1 battleship
SZ 114: 1 transport, 1 cruiser

UK:
SZ 98: 1 transport, 1 destroyer, 1 cruiser, 1 aircraft carrier (carrying 1 tactical bomber)
SZ 110: 1 cruiser, 1 battleship
SZ 111: 1 destroyer, 1 cruiser, 1 battleship

SZ 37: 1 Battleship
SZ 39: 1 transport, 1 destroyer, 1 cruiser

USA:
SZ 10: 1 transport, 1 destroyer, 1 cruiser, 1 aircraft carrier (carrying 1 fighter and 1 tactical bomber), 1 battleship
SZ 26: 1 transport, 1 submarine, 1 destroyer, 1 cruiser

JAPAN:
SZ 6: 1 transport, 1 submarine, 2 destroyers, 1 cruiser, 2 aircraft carriers (each carrying 1 fighter and 1 tactical bomber), 1 battleship
SZ 19: 1 transport, 1 submarine, 1 destroyer, 1 battleship
SZ 20: 1 transport, 1 cruiser
SZ 33: 1 destroyer, 1 aircraft carrier (carrying 1 fighter and 1 tactical bomber)

Another question, besides the game incentive toward cruiser unit, do you see some kind of historical rationalization behind this combined arms bonus?

Ok that would work, if you want anti air, then you could do the cruiser, carrier, battleship combo.

It wouldn’t make cruisers better alone, just necessary for the core defense of the battle group against all out air attacks. Might make them worth buying at 12.

For Japan and USA certainly a clean incentive.
For UK, it will be probably difficult to resist not getting at least one AAA umbrella against Luftwaffe.

But, on the other way, you don’t get the independant operation you can get with Marines-Unit with BB or Cruiser.
Which can increase action faster.

@Black_Elk:

How about instead of firing back against amphibious ground, the defender gets to fire back against the ship itself? Sort of like anti-air fire but with ships. Though bombardment capable ships are expensive so this roll would have to be restricted somehow, harder than aa gun fire to hit for the defender. But maybe, if the risk was to the ship rather than the ground, this would provide the requisite element of risk to the bombarding attacker, to prevent it being just a freebie, which is the only way I can see to make it work if you don’t pair the ship with a ground unit for bombardment, but instead want to separate the bombardment off into its own separate action.

Not exactly against warships, but should be said.
It was discuss elsewhere, here is a slightly different HR:
All Shore Bombardment are fired but allows
All defending INF+ART combo, able to make a preemptive strike 2@2 against incoming invaders. And single Artillery unit also, as in 1914.
Then casualties are removed.
Proceed to regular combat with additional ShoreBombardment treated as a regular roll.
Never more Shore bombardment than the number of ground units unload from Transport.

Well the anti air for battlegroup concept seems cool. I think the hope was that we could find a combined arms that just had units pairing 1:1. That one requires a pairing of 3 different units 1:1:1, but seems like it could encourage Cruiser purchases. I think in that case, people would be much less inclined to ever separate their cruisers, BB and CV once purchased or consolidated together.

Not sure if that’s everything we’re after, but at least its workable. Doesn’t bust the opening round, and gives a reason to buy the cruiser unit.

In this case, what would be the optimal way to handle the anti air fire? Hits at a 1 against all attacking air? Or restricted to some set number, like up to 3 fighters (similar to regular aaaguns) or 3 fighters per set of cruiser/bb/cv? That might be too under powered to make a difference. Probably easier to just make it like factory anti air fire, against all air that come at you.

@Black_Elk:

In this case, what would be the optimal way to handle the anti air fire? Hits at a 1 against all attacking air? Or restricted to some set number, like up to 3 fighters (similar to regular aaaguns) or 3 fighters per set of cruiser/bb/cv? That might be too under powered to make a difference. Probably easier to just make it like factory anti air fire, against all air that come at you.

I’m inclined to treat it exactly as an AAA unit: up to three planes.
After all, it is a known concept in ground combat adapted to Naval Battle and it requires 3 warships type, the number 3 is obviously on the board.

IC’s AAA seems too powerful and unrealistic: a defense @1 against infinite number of planes.
Defending Carriers are already much better than offensive ones.
Anti-Air is providing an additional defense.

@Black_Elk:

Well the anti air for battlegroup concept seems cool. I think the hope was that we could find a combined arms that just had units pairing 1:1. That one requires a pairing of 3 different units 1:1:1, but seems like it could encourage Cruiser purchases.

Not only Cruiser but also Battleship buying incentive.
Another reason to not give IC’s AAA capacity: you want to defend against more than 3 planes, buy another Cruiser and BB to join another Carrier.
I’m pretty sure it can change some buying from Destroyers and Subs to Cruiser and Battleship.

It still cost 12+16+20= at least 48 IPCs (68 with 2 Fgs) to get this additional defensive abilities.

Maybe this concept can be simply extended to each combo of BB+Cruiser gives 1 AAA capacity as long as there is a Carrier to protect.

So 2 BBs + 2 Cruisers + 1 Carrrier will provides an AAA against up to 6 planes.