PTs and GVs spawn on CV deck. PTs slide off aft of ship and "tumble" into water. GVs must be backed off deck and "tumble" into water. Once in the water (and the tumbling stops) they seem intact. PTs colliding with friendly ships aren't destroyed but their engines are rendered inoperative and they once again "tumble." Occasionally this tumbling will not cease and the game must be rebooted.