A-18 Appendix A –PFD
an active flight plan, a message displays on the
keyboard informing the unavailability of vectors
mode until an active flight plan has been added.
The autopilot navigation source can be either NAV or HDG,
therefore the autopilot and CDI sources can be different. If they
are not using the same navigation source, a cyan “AP not in
GPSS is displayed when in Vectors mode. Selecting NAV or
GPSS on the autopilot assures that this autopilot flies the Primary
Nav source, not the Heading Bug. Therefore, the autopilot will
capture and hold the nav source as indicated on the HSI and CDI.
Synthetic Vision Tab
See the description in the later part of Section 5.