Garmin G1000 Pilot’s Guide for Cessna Nav III
190-00498-07 Rev. A
442
AUTOMATIC FLIGHT CONTROL SYSTEM
SYSTEM
OVERVIEW
FLIGHT
INSTRUMENTS
EIS
AUDIO PANEL
& CNS
FLIGHT
MANAGEMENT
HAZARD
AVOIDANCE
AFCS
ADDITIONAL
FEATURES
APPENDICESINDEX
VERTICAL NAVIGATION MODES (VPTH, ALTV)
NOTE: VNV is disabled when parallel track or dead reckoning mode is active.
NOTE: The Selected Altitude takes precedence over any other vertical constraints.
VerticalNavigation(VNV)ightcontrolisavailable forenroute/terminalcruiseanddescent operationsany
timethatVNVight planningisavailable.Refer totheFlightManagement Sectionformoreinformationon
VNVightplans.Conditionsforavailabilityinclude,butarenotlimitedto:
•TheselectednavigationsourceisGPS.
•AVNVightplan(withatleastonealtitude-constrainedwaypoint)orverticaldirect-toisactive.
•VNVisenabled(VNV ENBLSoftkeypressedontheMFD).
•Crosstrackerrorisvalidandwithincertainlimits.
•Desired/actualtrackarevalidortrackangleerroriswithincertainlimits.
•TheVNVTargetAltitudeoftheactivewaypointisnomorethan250ftabovethecurrentaircraftaltitude.
Theightdirectormaybe armedforVNVatanytime, butnotargetaltitudesarecapturedduring aclimb.
TheCommandBarsprovideverticalproleguidancebasedonspeciedaltitudes(enteredmanuallyorloaded
fromthedatabase)atwaypointsintheactiveightplanorverticaldirect-to.TheappropriateVNVightcontrol
modesaresequencedby theightdirectortofollow thepathdenedbythe verticalprole.Uponreaching
thelastwaypointintheVNVightplan,theightdirectortransitionstoAltitudeHold Modeandcancelsany
armed VNV modes.
VERTICAL PATH TRACKING MODE (VPTH)
NOTE: If another pitch mode key is pressed while Vertical Path Tracking Mode is selected, Vertical Path
Tracking Mode reverts to armed.
NOTE: Pressing the CWS Button while Vertical Path Tracking Mode is active does not cancel the mode. The
autopilot guides the aircraft back to the descent path upon release of the CWS Button.
Whena verticalprole(VNV ightplan) isactive andtheVNV Keyis pressed,VerticalPath Tracking
Modeisarmedinpreparationfordescentpathcapture.‘VPTH’(or‘/V’whenGlidepathorGlideslopeMode
is concurrently armed) is annunciated in white in addition to previously armed modes. If applicable, the
appropriate altitudecapturemodeisarmedforcaptureofthenextVNV Target Altitude (ALTV) or the Selected
Altitude (ALTS), whichever is greater.
Figure 7-10 Vertical Path Tracking Armed Annunciations