CHAPTER 4
REFERENCE GUIDE
EFD1000 E5 Pilot’s Guide
Page 4-5
091-00086-001 ( )
In summary, loss or degradation of the EFI attitude solution is unlikely if the pilot assures
the proper operation of the pitot-static system. If the pitot or static system becomes
blocked, an ADAHRS internal sensor fails, or a CROSS CHECK ATTITUDE followed by an
ATTITUDE DEGRADED indication is frequent or persists, the attitude indication on the
EFI should be considered to be compromised. In this case, the pilot must crosscheck
other instruments for attitude reference until the cause of the problem has been
identified and resolved and normal system operation has been restored.
4.1.3. Heading
The ADAHRS also includes a slaved compass system that provides accurate magnetic
heading indications throughout most operating conditions and phases of flight. Its
electronic gyros compensate for turning and acceleration errors, and its remote fluxgate
compensates for gyroscopic precession errors, so there is no need for the pilot to adjust
heading throughout the flight. Nonetheless, all compass systems are subject to some
error, and the pilot should be aware of when and how the heading indication can
be affected.
The earth’s magnetic field is measured directly by a 3-axis fluxgate magnetometer built
into the Remote Sensor Module (RSM), and magnetic heading is derived from the flux
on a plane perpendicular to gravity, providing immunity from pitching and rolling
effects. Electronic gyros and accelerometers in the system are then used to stabilize
that raw heading data to eliminate the short-term turning and acceleration errors seen
in traditional magnetic compasses.
Together, these systems provide accurate heading indications even during aggressive
maneuvering. The gyros stabilize magnetic errors while maneuvering and are slaved
to the fluxgate, which continuously updates heading to compensate for gyroscopic
precession. The end result is a compass system that requires no pilot action to show
accurate magnetic heading throughout the flight.