I have a question about SAs such as Torpedo Protection or Evade Torpedoes. Does the roll apply to the entire attack roll, or must you roll for each torpedo?
For example, I attack a BB with Torpedo Protection and roll 6,6,1. Two hits. Does it: a) roll once and the Torpedo Protection applies to both hits (succeed or fail) b) roll for each of the two torpedo hits separately?
It varies by Special Ability depending on the wording.
Evade Torpedoes says a roll of 3 or higher causes the "attack" to fail. That means the die roll negates all torpedo hits from that attack roll.
Torpedo Protection says whenever a torpedo "hit" is rolled against the unit, a roll of 4 or higher causes that "hit" to deal one less point of hull damage. That means you have to roll for each individual torpedo hit as RAEVSKI said.