Definition
A solid-state electronic system that uses sensors such as accelerometers, rate gyros, and magnetometers to continuously measure an aircraft's pitch, roll, and heading, then sends that data to electronic flight displays and autopilots. It replaces the spinning mechanical gyros found in older attitude indicators and directional gyros.
Plain English
A small electronic box that figures out which way the aircraft is pointing and how it is tilted, then feeds that information to the cockpit displays.
Context Anchor
Seen in aircraft with electronic flight instruments, especially when discussing attitude displays, heading displays, and instrument system failures.
Derivation
Attitude here means the aircraft's orientation in space (nose up or down, wings level or banked), not a mood. Heading is the direction the nose is pointing. Reference System means it provides a steady source of truth for those values that other instruments and systems rely on.
Why Pilots Care
Supplies reliable attitude and heading data for instrument flight with higher reliability than older vacuum-driven gyro instruments.
Intuition Check
Attitude does not mean the pilot’s mood here; it means the aircraft’s position relative to the horizon. Heading does not always mean the route you intend to fly; it means the direction the aircraft’s nose is pointing.
Example Sentence 1
After the AHRS finished aligning during startup, the attitude indicator on the primary flight display came alive and showed wings level.
Example Sentence 2
In instrument conditions the attitude and heading reference system supplied steady pitch and heading data to the primary flight display.