CHAPTER 6
EXP
ANDED EMERGENC
Y AND ABNORMAL PROCEDURES
EFD1000/500 MFD Pilot’s Guide
Page 6-12
091-00006-001 REV B
EFD1000/500 MFD Pilot’s Guide
Page 6-13
091-00006-001 REV B
6.12.
Loss of GPS information
Position and flight plan data for the PFD and MFD is provided from aircraft GPS
equipment. The EFD displays may be configured to receive data from one or two
external GPS systems. In addition, when an RSM connected to the EFD includes an
emergency GPS, this information may be used if the aircraft GPS system(s) fail.
The Nav Map function in either the PFD or MFD follows an automatic position reversion
scheme to determine which GPS is the position source for the map. The primary GPS is
always the one selected by the pilot, either by the associated CDI nav source (PFD), or
via the menus (MFD). If the selected GPS fails, the EFD automatically switches to another
GPS (when installed), and will annunciate “GPS# Reversion”, where # represents the GPS
source providing position data.
If all external GPS systems fail, and an RSM GPS is connected to that display, the EFD will
use position data from the RSM and annunciate RSM GPS REVERSION EMER USE ONLY.”
In this case, the map data is approved for emergency use only.
Whenever the map has reverted to an alternate position source, all map features and
capabilities are retained, including the display of the flight plan from the selected GPS.
However, when the GPS position source is different from the source that generated
the flight plan, the flight plan is presented without showing an active (magenta) leg.
The flight plan and map data from each external GPS is retained independently. If two
external GPS were connected prior to, and if each had a different flight plan at the time
of failure, both of these flight plans are retained and can be viewed by the pilot.
In the unlikely event that there is a complete loss of all GPS data to an MFD, including
loss of the RSM GPS (if installed), the NAV Map is retained, the flight plan is removed,
and the map is no longer updated with aircraft position information. An annunciation
of “GPS POS FAILED” is presented in the center of the map, the airplane symbol is
removed,the map changes to a North-up orientation, and the map will no longer move
with the aircraft. Manual panning is still possible and all map features that are not GPS
position dependent continue to remain available, including relative terrain overlays.
CAUTION
In the event of complete GPS failure, the Nav Map
stops moving and orients North Up, the airplane
symbol is removed and reverts to a stationary
map with an accompanying “GPS POS FAILED” is
annunciated. In this case, the Nav Map may be
manually panned to correlate to the estimated
aircraft position determined by other means
.