The term 'CHANGED COURSE AT SEA' can be solved by the crossword solution 'TACKED', which is a sailing maneuver. Tacking is when a sailboat turns into the wind and then back again in order to change direction. This is done by shifting the sails from one side of the boat to the other, allowing the wind to push the boat in the desired direction. Tacking is an important skill for sailors to master in order to navigate the seas safely.