The number of aircraft units that can fly a naval air interception mission is limited by the # of aircraft (on your side) already in the sea area + 1.
Example:
The CW flies two long range fighters into the Italian coast sea area. They follow this up with a carrier fleet and a small invasion force. The Italians only have a single submarine in the sea area. Nevertheless, they decide to initiate a combat by flipping the submarine. Since the Italians have no airplanes in the area, they are only allowed to naval air intercept 0+1 aircraft so they intercept out a fighter. The CW have 2 aircraft in the sea area (their carriers don't count) so they are allowed to send in 3 aircraft. After fighting a round of combat, the Italians retreat to the sea box and are now allowed to fly in two more aircraft. This could be shaping up to be a big battle…
Rationale
One of the common complaints about the abstracted WIF naval system is the efficacy of land-based air (LBA). LBA can be effective for two reasons:
- their fighters are more powerful because they provide a full +1 in air-to-air combat instead of the fractions provided by carrier planes (note: there is an errata to an optional rule in the 2008 annual to fix this).
- you can potentially intercept an unlimited # of planes to a sea box using naval air interception.
This can put an invader at a profound disadvantage. Because they have to protect an invasion fleet that is usually in the 3 or 4 box, they must spend precious air missions to protect their fleet with LBA. The defender, on the other hand, can naval air intercept an unlimited # of aircraft to a lower box in hopes of getting the "pounce". The Germans & Italians especially can get absurd amounts of aircraft into the 1 box. With a naval plane and the fact that the other guy has to search as well, this can lead to ~30% chance of the invasion fleet getting pummeled. And all because of some lucky search dice.
It's a bit absurd when you consider that these planes are very short range (usually 3 or 4 hexes), may be scattered all over the coast, and yet they are all able to fly out to sea and converge on a fleet that could be 15-20 hexes away from the vast majority of them?!?
By limiting the # of aircraft that can intercept to the # of planes already at sea, this forces the defender to have to spend air missions to defend a sea area as well. If a battle drags on multiple rounds, I can at least justify the notion of more and more aircraft being sucked into the battle. But certainly, the initial battle shouldn't happen the way it does in standard WIF.
