Port Royale 3

An emergency repair takes place on the nautical map when one of the ships in your convoy reaches less than 3% health. Ships slowly degrade as they sail the seas and can also sustain damage during a naval battle. As soon as a ship requires an emergency repair, the achievement will unlock.

TIP: If you are having trouble unlocking this, try and sustain massive damage with a single ship. Then manually sail the ship around the map until it degrades to 3% health.