Which instrument became the de facto standard to indicate roll and yaw in modern aircraft?

• A. Turn coordinator
• B. Attitude indicator
• C. Turn-and-slip indicator
• D. Vertical speed indicator

Answer: (A)

The instrument that shows both roll and yaw in modern aircraft is the turn coordinator. It uses a tilted gyroscope so it responds to rotation about both the vertical axis (yaw) and the aircraft’s longitudinal axis (roll). Because of this cant, the miniature airplane on the instrument banks as you roll, giving you immediate feedback on roll rate, and the pointer indicates the rate of turn. This combination is incredibly helpful for keeping the wings coordinated during turns, especially when the horizon is hard to see.

By contrast, the attitude indicator only shows the aircraft’s attitude relative to the horizon (bank and pitch) and doesn’t provide roll rate information. The older turn-and-slip indicator primarily shows rate of turn and the slip/skid tendency, but not roll rate. Vertical speed indicates climb or descent, not turning or roll. The turn coordinator’s ability to convey both roll and yaw information quickly is why it became the standard for this purpose.