What does the Turn Coordinator instrument indicate?

The Turn Coordinator instrument is specifically designed to indicate the rate of turn and the coordination of the aircraft during those turns. It provides valuable information to the pilot regarding how quickly the aircraft is turning and whether the turn is performed in a coordinated manner, which is essential for maintaining control and preventing adverse yaw or skids during the maneuver.

When an aircraft is in a properly coordinated turn, the airplane will not experience any lateral forces that could destabilize it; the Turn Coordinator helps pilots ensure that their turns are executed correctly and safely. Understanding the turn rate is crucial for both maintaining a smooth flight and for various flying operations, especially in situations where accurate heading changes are necessary, such as in instrument flight rules (IFR) operations or during training scenarios.

In contrast, the other options listed do not pertain to the specific function of the Turn Coordinator. For example, altitude changes are indicated by an altimeter, airspeed is measured by aairspeed indicator, and climb rate is shown on a vertical speed indicator. Each of these instruments has its own specialized function that is distinct from the Turn Coordinator's purpose.