GDL-49 and Levels of Radar Returns

"O. Sami Saydjari" wrote in message
...
In googling around a bit, I found the following:

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At: http://www.weatherzone.com.au/misc/g...y.jsp?letter=V

"Video Integrator and Processor, which contours radar reflectivity (in
dBZ) into six VIP levels:
• VIP 1 (Level 1, 18-30 dBZ) - Light precipitation
• VIP 2 (Level 2, 30-38 dBZ) - Light to moderate rain.
• VIP 3 (Level 3, 38-44 dBZ) - Moderate to heavy rain.
• VIP 4 (Level 4, 44-50 dBZ) - Heavy rain
• VIP 5 (Level 5, 50-57 dBZ) - Very heavy rain; hail possible.
• VIP 6 (Level 6, 57 dBZ) - Very heavy rain and hail; large hail
possible."

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At:
http://www.garmin.com/manuals/773_Ga...deAddendum.pdf

Ok, now, from the Nextrad intensity table on page 13 of the Garmin
"400/500 Series garmin Options Displays", I learned:

GREEN means 5-30 dBZ
YELLOW means 30-55 dBZ
RED means 55-75 dBZ

So...
Green is VIP Level 1
Yellow is VIP Levels 2,3,4
Red is VIP levels 5 and 6


Don't draw this conclusion unless you know exactly what the standards Garmin
is using and what the radar system is using and whether they are compatible
with the VIP levels that you are using. Nexrad seems to use different
scales depending of what mode it is in and additionally, there are at least
2 VIP scales (maybe more), one that has six levels and one that has 15
levels. It also seem to produce different dbz readings than an airborn
radar. There was a major airline accident in the SE (Georgia I think) where
an airliner flew into a 50+ dbz echo (on an airborn radar) and the airliner
was virtually destroyed by hail (the engines where broken up internally. I
doubt that this is what Garmin is displaying as a borderline yellow/red
echo. There is a good chance that you will not survive flying into a VIP 4
storm.

Mike
MU-2