Definition
Any cockpit instrument whose primary function is to display the aircraft's heading or direction of flight relative to a reference such as magnetic north or true north. In instrument flying, this category includes the magnetic compass, the heading indicator (directional gyro), and the horizontal situation indicator (HSI).
Plain English
An instrument that tells the pilot which way the airplane is pointing.
Context Anchor
Seen in instrument flying when using the magnetic compass, heading indicator, or similar cockpit display to control turns and maintain a heading.
Why Pilots Care
Reliable heading information prevents over- or under-turning when the directional gyro is unreliable or during timed compass turns.
Intuition Check
Do not read this as any instrument that gives general navigation guidance. Here it means an instrument that indicates the aircraft’s heading: the direction the nose is pointed.
Example Sentence 1
During the compass turn discussion, the pilot cross-checks the magnetic compass against the heading indicator, since both are direction-indicating instruments and should agree in steady, level flight.
Example Sentence 2
During partial panel practice, the magnetic compass became the sole direction-indicating instrument available.