Salvage Bonus

In Ship PvP combat, when a pirate sinks an enemy vessel, they are given a bonus depending upon the level and bounty of the ship sunk. This bonus is rewarded in Salvage points, which are applied to their own ship's battle damage.

So, it is feasible for a ship to be in combat and not need repairs; if it was victorious and the salvage completely restored its hull and sails.