Fast Developing Thunderstorm; Low Altitude Tilt Management - Honeywell PRIMUS 660 Pilot's Manual

D
Under the right conditions, a dangerous thunder bumper can
develop in 10 minutes, and can in fact spawn and mature under the
radar beam as the aircraft approaches it, as shown in figure 5–14.
If flying at 400 kt groundspeed (GSPD), a fast developing thunderstorm
that spawns 67 NM in front of the aircraft can be large enough to
damage the aircraft by the time it arrives at the storm.
D
At low altitude, the tilt should be set as low as possible to get ground
returns at the periphery only, as shown in figure 5–15.
CORRECT
Excess up–tilt should be avoided as it can illuminate weather above
the freezing level.
NOTE: The pilot should have freeze level information as a part of
the flight planning process.
A28–1146–111
REV 2
PRIMUS

Fast Developing Thunderstorm

Figure 5–14
WRONG

Low Altitude Tilt Management

Figure 5–15
R
660 Digital Weather Radar System
THUNDERSTORM MATURES
AS IT APPROACHES
FREEZING
LEVEL
AD–35699@
FREEZING
LEVEL
AD–35700@
Radar Facts
5-13