What does a turn coordinator indicate regarding an aircraft's movement?

The turn coordinator is an important instrument used in aviation to provide pilots with critical information about an aircraft's movement, specifically in relation to its yaw and roll axes. It indicates the rate of turn and helps pilots maintain coordination during turns. The value provided by this instrument is particularly useful for ensuring that the aircraft is not skidding or slipping during a turn, which can compromise safety and performance.

When the turn coordinator shows that the aircraft is in a coordinated turn, it also reflects how the aircraft is banking, or rolling, in relation to its yaw axis, thus confirming the relationship between these movements. This makes it essential for maintaining effective control of the aircraft as it maneuvers through turns and changes in direction.

In contrast, the other choices do not accurately describe the primary function of a turn coordinator. The angle of bank is important in turning but is not the sole indicator provided by the turn coordinator; it helps in maintaining coordination, which can include banking beyond just 30°. While the aircraft's attitude is relevant, the turn coordinator specifically relates to its rate of turn rather than overall attitude with reference to the longitudinal axis. Lastly, the instrument does not measure airspeed; instead, it focuses on the rate at which the aircraft is turning. This makes the