Pilot's Guide

190-00663-02 Rev. B
Garmin G1000 Pilot’s Guide for the Hawker Beechcraft C90A/GT/GTi
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HAZARD AVOIDANCE
•NEXRADbasereectivitydoesnotprovidesufcientinformationtodeterminecloudlayersorprecipitation
characteristics(wethailvs.rain).Forexample,itisnotpossibletodistinguishbetweenwetsnow,wet
hail, and rain.
•NEXRADbasereectivityissampledattheminimumantennaelevationangle.AnindividualNEXRAD
sitecannotdepicthighaltitudestormsatcloseranges.Ithasnoinformationaboutstormsdirectlyover
the site.
•Whenzoomedintoarangeof30nm,eachsquareblockonthedisplayrepresentsanareaoffoursquare
kilometers.Theintensitylevelreectedbyeachsquarerepresentsthe highest levelofNEXRADdata
sampledwithinthearea(Figure6-12).
•TheNEXRADweatherproductdoesnotcontainreal-timeinformation.Theradardatausedtoformthe
compositeimagemaybesignicantlyolderthanthedisplayedageoftheNEXRADweatherproduct.
Figure 6-12 NEXRAD Data - Zoomed
Block represents
4 km
2
ThefollowingmaycauseabnormalitiesindisplayedNEXRADradarimages:
•Groundclutter
•Strobesandspuriousradardata
•Sunstrobes(whentheradarantennapointsdirectlyatthesun)
•Interferencefrombuildingsormountains,whichmaycauseshadows
•Metallicdustfrommilitaryaircraft,whichcancausealterationsinradarscans