Talk:Tutorial: FAQ/@comment-116.88.153.81-20150124092302/@comment-24356282-20150124092937

Straight from FAQ

To avoid sinking your ship, make sure they are not heavily damaged (大破) before a battle. A ship will never sink if she enters battle in good condition (no damage / minor damage [小破] / moderate damage [中破]).

When ships in good condition receive excessive damage they will be left with 1 HP, which can be repaired to full health. If you choose to advance (進撃) with your ship heavily damaged, she will be at risk of being sunk.

Sunken ships are lost forever and not retrievable. If you need to risk your damaged ships to proceed to the next battle, make sure to equip some form of damage control equipment on them. It allows your ships to be revived if they are sunk by the enemy.

Both night and day battle are considered the same battle, so ships which are brought to "heavy damage" during the same battle can enter night battle without fear of sinking.

Video about ships which were heavily damaged during the day before proceeding to night battle: - http://www.nicovideo.jp/watch/sm22148662 | https://www.youtube.com/watch?v=3CayD735o04