Glidepath Mode (Gp) - Garmin GFC 600 Pilot's Manual

GLIDEPATH MODE (GP)

Glidepath Mode is available in aircraft with an SBAS GPS-enabled
NOTE:
navigator. The GMC 605 may annunciate GP as an armed vertical mode
when the APR Key is selected even when interfaced to a GPS navigator that
is not capable of calculating a glidepath. In that case GP will never become
the active vertical mode.
Glidepath mode is used to track a glidepath generated by a GPS navigator with
WAAS or other Satellite Based Augmentation System (SBAS) capability.
Selecting Glidepath Mode:
1) EXTERNAL NAVIGATOR: Ensure a GPS approach with vertical guidance
(LPV, LNAV/VNAV, LNAV+V, LP+V) is loaded into the active flight plan. The
active waypoint must be part of the flight plan (cannot be a direct-to a
waypoint not in the flight plan).
2) Ensure that GPS is the selected navigation source.
3) GMC 605: Press the APR key. The AFCS maintains the current mode but
arms Glidepath mode.
4) Upon reaching the glidepath, the AFCS vertical mode transitions to
Glidepath Mode and begins to capture and track the glidepath.
Some RNAV (GPS) approaches provide a vertical descent angle
NOTE:
as an aid in flying a stabilized approach. These approaches are NOT
considered Approaches with Vertical Guidance (APV). Approaches that are
annunciated on the HSI as LNAV or LNAV+V are considered Nonprecision
Approaches (NPA) and are flown to an MDA even though vertical glidepath
(GP) information may be provided.
190-01488-00 Rev. B
GI 285 Annunciating Indicated Airspeed Mode
Garmin GFC 600 Pilot's Guide
AFCS
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