Explanation should include the following:
- Aircraft use two types of turn indicators—turn-and-slip indicators and turn coordinators.
- Because of the way the gyro is mounted, the turn-and-slip indicator shows only the rate of turn in degrees per second.
- The turn coordinator is mounted at an angle, or canted, so it can initially show roll rate. When the roll stabilizes, it indicates rate of turn.
- Both instruments indicate turn direction and quality (coordination), and also serve as a backup source of bank information in the event an attitude indicator fails.
- Coordination is achieved by referring to the inclinometer, which consists of a liquid-filled curved tube with a ball inside.
- The turn-and-slip indicator uses a pointer, called the turn needle, to show the direction and rate of turn.
PLT187