Cockpit Reference Guide

Garmin G1000 Pilot’s Guide for the Piper PA-46 Meridian
190-00763-02 Rev. A338
HAZARD AVOIDANCE
SYSTEM
OVERVIEW
FLIGHT
INSTRUMENTS
EICAS
AUDIO PANEL
& CNS
FLIGHT
MANAGEMENT
HAZARD
AVOIDANCE
AFCS
ADDITIONAL
FEATURES
APPENDICESINDEX
SYSTEM
OVERVIEW
FLIGHT
INSTRUMENTS
EICAS
AUDIO PANEL
& CNS
FLIGHT
MANAGEMENT
HAZARD
AVOIDANCE
AFCS
ADDITIONAL
FEATURES
APPENDICESINDEX
Inareas ofmultipleheavy cells,use theVerticalScanfeaturealongwith antennatilt management to
examinetheareas.Remembertoavoidshadowedareasbehindtargets.
Figure 6-52 The Blind Alley
The Blind Alley at Close Range The Large Storm Behind
Tornadoes
Therearenoconclusiveradartargetreturncharacteristicswhichidentifyatornado.However,tornadoes
maybepresentifthefollowingcharacteristicsareobserved:
•Anarrow,nger-likeportionextendsandinashorttimecurlsintoahookandclosesonitself.
•Ahook,whichmaybeinthegeneralshapeofthenumeral6(numeral9inthesouthernhemisphere),
especially if bright and projecting from the southwest quadrant (northeast quadrant in the southern
hemisphere) of a major thunderstorm.
•V-shapednotches.
•Doughnutshapes.
These shapes do not always indicate tornadoes, and tornado returns are not limited to these characteristics.
Conrmedradarobservationsoftornadoesmostoftenhavenotshownshapesdifferentfromthoseofa
normal thunderstorm display.
Hail
Hail results from updrafts carrying water high enough to freeze.  Therefore, the higher the top of a
thunderstorm,thegreatertheprobabilitythatitcontainshail.Verticallyscanningthetargetreturncan
givetheradartopofathunderstormthatcontainshail.Radartopisthetopofastormcellasdetectedby
radar.Itisnottheactualtop,ortruetopofthestorm.Theactualtopofastormcellisseenwiththeeyes
inclearairandmaybemuchhigherthantheradartop.Theactualtopdoesnotindicatethetopofthe
hazardous area.
Hailcanfallbelowtheminimumreectivitythresholdforradardetection.Itcanhavealmofwateron
itssurface,makingitsreectivecharacteristicssimilartoaverylargewaterdroplet.Becauseofthislmof
water,andbecausehailstonesusuallyarelargerthanwaterdroplets,thunderstormswithlargeamounts
ofwethailreturnstrongersignalsthanthosewithrain.Somehailshaftsareextremelynarrow(100yards