The number of fighters you "need" per bomber really depends on what kind and what level of opposition you expect to face en route to, over, and returning from the target.ORIGINAL: Shark7
]Which makes sense. When you send out the bombers to attack the enemy, they'll need to be escorted but you also have to keep some fighters at home to protect the carrier. Honestly you need 2 fighters for every 1 bomber.
The ratio of fighters to bombers required to give a raid adequate protection is additionally dependent upon the size of the raid; a thousand-bomber raid can be given a relatively-lighter escort than a hundred-bomber raid and still have at least as effective an escort.
