ORIGINAL: castor troy
If attack is not overwhelming, I would expect 4-7 bomb hits in best case - too few to disable CV, and damages would go mainly to SYS, so will be easily repaired in every port (250kg bombs even seems to be too weak to disable guns in most cases). I doubt Allied player will retire CV if it is still operational, and have almost no FLT damage.
I would generally exchange ONE hit with torpedo, over 10 hits with 250kg bombs. It have great chance to make over 50 combined damage (plus FLT). Two torpedo hits almost surely close any CV.
However, against CVEs, and non-armored ships 250kg bombs are sufficient, they should damage them seriously.
2 bombs in theory have twice chance to hit, than 1 bomb, but difference in penetration is far too high for this exchange (and sum of effects is also the same than 500kg, or even less, than 800kg) to be worth it.
While I of course also preferre torp hits over bomb hits, it depends on the exchange ratio. Trying to sink a USN CV with two torp hits is like a chance of 1:5, usually I am able to save a CV from such a damage. Now if the carrier would be hit by 20 250kg bombs, I'd say the ship is sunk 100% of the time as that would mean several ammo and fuel storage explosions too, when the bombs alone would be enough to sink the carrier. I'd give it a 70/30 chance to have the flight deck closed after two torp hits but still, 20 bombs would sink it so I'd know what I preferre.
Don't know guys. To be honest things also depend on which mod we're playing. I do play DBB, where the effect of the GP bombs have been reduced... now a 250kg Japanese bomb can still penetrate the deck of an American CV, but it's almost impossible to cause enough damage to really hurt her (I've been involved in not less than 3 CV encounters with allied CVs in DBB, and the 250kg bombs rarely caused enough damage to him)...while a 500kg bomb is able to really screw the day of a CV, cause it always penetrate it's deck and it has enough explosive power to easily create an ammo/fuel explosion.
My choice? I take 1 500kg (not to talk about the 800kg) over 2x250kg everyday, even if I have more chances to hit her. What I hit, I wanna hit as hard as possible.