A28-1146-102-00
Radar Facts
5-46
Mode annunciation for the turbulence detection mode is the /T legend
that is added to the WX annunciation. The resultant annunciation is
WX/T for weather and turbulence. The color bar legend on the
dedicated radar indicator includes a T within a soft white square
whenever turbulence detection is turned on. EFIS/MFD does not have
a color bar legend.
The PRIMUS
â
880 Digital Weather Radar measures the motion of
raindrops to determine areas of turbulence. The radar must detect
precipitation before it can detect turbulence. It cannot detect clear air
turbulence.
WARNING
THE PRIMUS
â
880 DIGITAL WEATHER RADAR CAN ONLY DETECT
TURBULENCEWITHINAREASOFPRECIPITATION.ITCANNOTDE-
TECT CLEAR AIR TURBULENCE.
Theturbulencedetectionthresholdismoderateturbulence.Thatis,any
area of raindrop motion that is detected as moderate, severe, or
extreme turbulence is displayed in white. Areas shownas turbulentare
at least moderate turbulence and can be severe, extreme, or
combinations of the three levels of turbulence. All three must be
avoided.
Turbulence is most accurately measured within ?30_ of straight
ahead. Turbulence measurements outside this area experience
reducedaccuracy.Thereducedaccuracyresultsfromtheeffectsofthe
antenna scan angle and aircraft motion. Levels of turbulence are
described in the Airman’s Information Manual and are shown in figure
5-34.
To Next Page
Loading...
