Definition
The component of a remote indicating compass system that displays the aircraft's magnetic heading to the pilot on the instrument panel. It receives heading information electrically from a remotely mounted flux valve (magnetic sensor) and presents it on a rotating compass card, typically as part of a horizontal situation indicator or similar instrument.
Plain English
The dial on the panel that shows which way the airplane is pointing. It gets its information from a magnetic sensor mounted somewhere else in the aircraft, away from electrical interference.
Context Anchor
Seen in instrument flying discussions of remote indicating compass systems and during cockpit instrument checks.
Why Pilots Care
It provides stable heading information unaffected by the turning and acceleration errors that affect a wet compass.
Intuition Check
Do not read “heading” as the airplane’s path over the ground. Here, heading means the direction the nose is pointed, measured against magnetic direction.
Example Sentence 1
After takeoff, the pilot cross-checked the heading indicator unit against the standby magnetic compass and found both agreed within two degrees.
Example Sentence 2
During the ILS approach the heading indicator unit showed a steady 180 degrees.