Garmin GPS 400W,GNC 420W Pilot's Manual & Reference

Also see for 400W Series: Supplemental Flight manual Pilot's guide addendum Manual supplement Pilot's guide addendum Quick reference guide

Contents

Garmin GPS 400W,GNC 420W Pilot's Manual & Reference Manual pdf 93 page image

5 - PROCEDURES83Basic Approach OperationsBasic Approach OperationsThe 400W-series provides precision and non-preci-sion approach guidance using its built-in GPS receiver.The moving map pages can also be used as a supple-mental aid to situational awareness for ILS, VOR, andNDB approaches (and non-precision localizer-basedapproaches), but the localizer and glideslope receiversMUST be used for primary approach course guidance.The 400W-series also provides GPS precision capa-bility, known as LPV and LNAV/VNAV approaches.LNAV+V approaches provide vertical guidance but arenot precision approaches.Approaches designed specifically for GPS are oftenvery simple and don’t require overflying a VOR orNDB. Currently, many non-precision approaches have“GPS overlays” to let you fly an existing procedure(VOR, VOR/DME, NDB, RNAV, etc.) more accuratelyusing GPS. To date, there are over 2,400 GPS-onlyapproaches and over 2,900 GPS overlay approachesworldwide.Many overlay approaches are more complex (incomparison to GPS-only approaches). The 400W-series unit displays and guides you through each legof the approach — automatically sequencing througheach of these legs, up to the missed approach point(MAP). Approaches may be flown “as published” withthe full transition — using any published feeder routeor initial approach fix (IAF) — or may be flown with avectors-to-final transition.Flight mode annunciations are provided in thelower left corner of the display indicating the currentmode of flight.Annunciation DescriptionLPV Follow lateral and vertical guidance to LPVminimums. A yellow background indicatesthe current VPL and/or HPL values are notadequate for the approach and is an earlyindication that downgrading will occur ifconditions do not improve.L/VNAV GPS approach identified in the database asLNAV/VNAV. Fly to LNAV/VNAV minimums.LNAV+V Non-precision GPS approach with advancedvertical guidance. Note that some LNAV/VNAV approaches are not yet marked inthe database as such and will show up asLNAV+V. If the chart shows the approach asLNAV/VNAV, it can be flown to LNAV/VNAVminimums.LNAV Non-precision GPS approach or non-GPSapproach, such as ILS or Localizer.MAPR Missed Approach, indicates the system isproviding missed approach integrity andCDI full-scale deflection ±0.3NM. This alsoshows that the pilot has initiated a MissedApproach by pressing the OBS key aftercrossing the MAP.ENR En route, CDI full-scale deflection is 2.0 NMor current CDI scale selection, whichever issmaller.TERM Terminal, CDI full-scale deflection is 1.0 NMor current CDI scale selection, whichever issmaller.DPRT Departure, indicates the system is usingnon-precision approach integrity. HAL = 0.3and CDI full-scale deflection is 0.3 NM.OCN Oceanic, CDI full-scale deflection is 2.0 NM.LOW ALT(lower window)In LNAV+V, LNAV/VNAV, or LPV approaches,the LOW ALT annunciation indicates theaircraft’s estimated height is lower than theFinal Approach waypoint height by morethan the current VPL plus 50 meters.