Which instrument uses a directional gyro to display the heading with respect to magnetic north?

• A. Magnetic compass shows heading.
• B. DirectionaL gyro displays the aircraft's heading with respect to magnetic north.
• C. Attitude indicator shows pitch and roll.
• D. Airspeed indicator shows speed.

Answer: (B)

Heading is the aircraft’s orientation relative to magnetic north, and a directional gyro provides a stable reference for that heading. The gyro uses a fast-spinning rotor whose axis stays fixed in space; when the aircraft yaws, the gyroscopic action causes the readout to shift, showing the current heading. The instrument is set and read against magnetic north, and periodic realignment with the magnetic compass keeps it accurate. Other instruments don’t display heading using a directional gyro: the attitude indicator shows pitch and roll, the airspeed indicator shows speed, and the magnetic compass (while it shows heading) isn’t gyro-driven. So the instrument that uses a directional gyro to display heading with respect to magnetic north is the one that presents the headingReadout based on that gyro.