[Ref Pilot’s Handbook of Aeronautical Knowledge, FAA-H-8083-25B Page 8-20]
Attitude and Heading Reference System (AHRS) processes and sends attitude information to the PFD in order to generate the pitch and bank information of attitude indicator
AHRS receives heading information from a magnetometer that senses the earth’s lines of magnetic flux. This information is then processed and send out to the PFD.
Benefits of development in AHRS and EFD
The development of the (AHRS) and Electronic flight displays (EFD) have replaced free-spinning gyros with solid-state laser systems that are capable of flight at any attitude without tumbling.