Garmin G1000 Mooney M20TN - Manual (Page 291)

Garmin G1000 Pilot’s Guide for the Mooney M20M/M20R/M20TN 190-00647-01 Rev. B 280
HAZARD AVOIDANCE
SY
STEM
O
VER
VIEW
FLIGHT
INSTRUMENTS
EIS
AUDIO P
ANEL
& CNS
FLIGHT
MANA
GEMENT
HAZARD
AV
OID
ANCE
AFCS
ADDITIONAL FEA
TURES
APPENDICES
INDEX
NEXRAD L
IMITATIONS
NEXRAD radar images may have certain limitations:
• NEXRAD base reflectivity does not provide sufficient 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 reflectivity 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 reflected by each square represents the highest level of NEXRAD data
sampled within the area (Figure 6-12).
Figure 6-12 NEXRAD Data - Zoomed
Block Area is 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