Which instrument is considered a supporting instrument for maintaining pitch during a standard rate turn?

The correct instrument that serves as a supporting tool for maintaining pitch during a standard rate turn is the attitude indicator. This instrument provides essential information about the aircraft's orientation relative to the horizon. In a standard rate turn, maintaining the correct pitch is crucial to ensure the aircraft does not nose up or down excessively, which could lead to altitude loss or gain.

The attitude indicator displays the aircraft's attitude in relation to the horizon, allowing the pilot to visualize whether the aircraft is climbing, descending, or maintaining level flight during a turn. By referencing this instrument, a pilot can make small adjustments to the elevator control to maintain the desired pitch angle. This is especially important in instrument flying, as pilots might not have visual references outside the cockpit to determine the aircraft's orientation in relation to the horizon.

While the airspeed indicator provides information about the aircraft's speed and can indirectly influence pitch control, it does not directly aid in maintaining pitch during a turn. The manifold pressure gauge is primarily associated with power settings of the engine, and the vertical speed indicator measures the rate of ascent or descent. However, these instruments do not provide the specific information needed to monitor and maintain the aircraft's pitch attitude effectively during a standard rate turn. Thus, the attitude indicator is the most