High-energy turn

A high-energy turn (HET) is a maneuver that allows one to turn a starship very rapidly. The odds of success varies greatly upon the mass of the starship in question. By using additional energy, the ship can be made to turn at a much higher rate than usual. This allows a ship to make up to a 180° turn nearly instantaneously. As one might expect, this is not good on the ship. The hull, systems, and crew take a tremendous strain. Eventually this strain will result in a breakdown. Some ships are better at making HETs without having a breakdown and ships with superior flight controllers can make more HETs without suffering a breakdown. It is also called a "warp turn" because performing an HET requires the generation of a warp field. (Star Fleet Battles)