What is the essential difference between Magnetic Heading and Relative Heading?

What is the essential difference between Magnetic Heading and Relative Heading?

• A. Magnetic Heading uses Earth's magnetic field as reference; Relative Heading uses the object's current facing direction as the 0/360 azimuth.
• B. Magnetic Heading uses true north; Relative uses magnetic north.
• C. Magnetic Heading is used for navigation only in ships; Relative Heading only for aircraft.
• D. Magnetic Heading is derived from GPS; Relative Heading from INS.

Answer: (A)

The essential idea is the reference frame used to define the direction. Magnetic heading is measured relative to magnetic north—the direction the Earth’s magnetic field points—so the angle is from magnetic north clockwise to the aircraft’s nose. Relative heading, on the other hand, is the direction the aircraft is facing relative to its own forward axis, effectively using the nose as 0/360 regardless of any external north reference. In practice, magnetic heading can shift with location and time due to magnetic variation, while relative heading stays tied only to the aircraft’s orientation itself. The other statements mix external references (like true north or GPS/INS) or apply unrelatedly to different platforms, so they don’t describe these two concepts accurately.

The essential idea is the reference frame used to define the direction. Magnetic heading is measured relative to magnetic north—the direction the Earth’s magnetic field points—so the angle is from magnetic north clockwise to the aircraft’s nose. Relative heading, on the other hand, is the direction the aircraft is facing relative to its own forward axis, effectively using the nose as 0/360 regardless of any external north reference. In practice, magnetic heading can shift with location and time due to magnetic variation, while relative heading stays tied only to the aircraft’s orientation itself. The other statements mix external references (like true north or GPS/INS) or apply unrelatedly to different platforms, so they don’t describe these two concepts accurately.