Glidepath Mode
Some RNAV (GPS) approaches provide advisory vertical guidance 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+V’ or ‘LP+V’ should be flown in compliance with any stepdown altitude constraints and to an MDA, until visual reference with the landing environment is established, even though vertical glidepath (GP) information may be provided.
When flying an autopilot-coupled ‘LNAV+V’ or ‘LP+V’ approach with GP Mode active, the aircraft will not level off at the MDA even if the MDA is set in the altitude preselect. A different vertical mode (e.g., VS or FLC) must be selected prior to MDA (as altitude preselect) to arm ALTS Mode
Glidepath Mode is used to track the glidepath when executing an RNAV (GPS) Approach. When GPS Approach Mode is armed, Glidepath Mode is also automatically armed.
Upon reaching the glidepath, the flight director transitions to Glidepath Mode and begins to capture and track the glidepath, provided the following conditions have been met:
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An RNAV approach providing vertical guidance is loaded into the active flight plan.
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The active waypoint is the final approach fix (FAF) or a subsequent waypoint.
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Vertical deviation is valid.
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The CDI is at less than full-scale deviation.
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Automatic sequencing of waypoints has not been suspended (no ‘SUSP’ annunciation on the HSI).