Battleship with three players
Short answer: classic Battleship is a duel, the rules are written for two. Three people can still play, and here is how it is usually done.
Questions and answers
Is there a three-player mode?
No, a game is always one on one. Three players use a tournament: the winner stays, the loser hands over the seat.
How long is the wait?
A usual game takes a few minutes, so waiting your turn in a round of three is short.