Which indicator represents a standard-rate turn to the left?

To determine which indicator signifies a standard-rate turn to the left, it's important to understand the function of the turn coordinator or the attitude indicator in an aircraft. Typically, the turn coordinator includes a rotating airplane symbol with an inclinometer and a gimbal, which shows the rate of turn in degrees per second.

A standard-rate turn is defined as a turn in which the aircraft makes a complete 360-degree turn in two minutes, translating to a rate of three degrees per second. When indicating a left turn, the aircraft symbol will deflect to the left of the centerline on the indicator.

In this scenario, when identifying the correct indicator for a standard-rate turn to the left, it's essential to recognize the specific design and orientation of the indicator. The chosen answer accurately represents the left turn as the airplane symbol should tilt left while the rate of turn aligns within the standard limits. This visual cue is critical for pilots to maintain proper control and orientation while maneuvering the aircraft.

Such understanding of the indicators used during flight becomes second nature over time through training and practice, ensuring safety and efficiency during turns.