@Schulz A warning, those attachments give the bonus to the air unit for its regular attacks so long as one or more enemy relevant ships are present, meaning that the added power may be used to hit other air units too if hits from fighters can be assigned to air as well as sea units. For example, 4 fighters attacking 1 carrier with 2 fighters will all have the +1 attack bonus, thus increasing their ability to hit not only the carrier but also the fighters.

Practically, these are not bonus for attacking ships but bonus for attacking whatever force with at least 1 relevant ship.

If you want, you can change option name="number" value="1000" to option name="number" value="1" if you want to restrict the bonus to the number of enemy relevant ships. For example, if it is 1, then 4 fighters attacking 1 carrier and 2 fighters will have only 1 attacking fighter having the bonus so long as the carrier is not removed from the battle.

@Schulz said:

I'm not sure about giving this bonus to defending fighters on carriers as well.

If you change defence to offence:defence in those attachments, both fighters on carriers and fighters scrambled to sea will have the +1 defence bonus.

@Cernel

It works! Thank you so much.

I'm not sure about giving this bonus to defending fighters on carriers as well. Fighters already have more defense than attack in the current game. But I'll think about it again if this would enhance the game.

Yeah, bombers should probably be excluded from this feature.

Here are the current unit stats that I'm still working on to find the most correct prices. The goal is making air units cheaper and more effective against ships while also not making ships useless. Subs look useless to me right now; they probably need a cost reduction.

Fighters also scramble into all nearby sea zones. They also have 1 air attack and 2 air defense on escort/intercept missions, while bombers have just 1 air attack.

@Schulz said:

I'm working on a big update for this map, improving balance, game graphics, correcting the historical setup for May 1942, and placing more emphasis on air unit cost efficiencies against ships, as was historically true in World War II.

I would like to give a +1 attack bonus to fighters and bombers against ships (excluding subs and transports). How could I do that?

You can do it two ways.

The first way is by having a territory effect in every sea zone giving the bonus to the air units. I strongly suggest against doing it this way because then you may have to add the territory effect in the battle-calculator.

The second way is to have as many of these supports as the number of combat (non-v3-transport) ships types which can be hit by the air units:

AAA = a name of your choice, different amongst the attachments (You can just use the name of the ship.)
BBB = the name of the ship
CCC = the list of the air units each separated by :
DDD = a name of your choice, the same for all attachments
EEE = the list of all players in the game (comprising "Neutral" if relevant) each separated by :

Are you sure that defending fighters on carriers or scrambled aircraft should not have the bonus against ships? If they should too, use offence:defence instead of defence. I would use the former also for air units which can never actually defend against ships if that makes the most sense.

option name="number" value="1000" is just meant to be infinite if there is not a way to set infinite here (I don't know.). You may try to test if option name="number" value="-1" is accepted as infinite (I guess not.).

I have not tested this. I could have written or assumed something wrong: you need to test it.

Realistically, if by bombers you mean level bombers dropping bombs on ships from high or medium altitude (for example, B-17 bombing ships), these bombers proved very scarcely effective against underway ships (almost never hitting anything) (but fairly effective against ships in port or anyway not-moving ships).