Fast Developing Thunderstorm; Low Altitude Tilt Management - Honeywell Primus 880 Pilot's Manual

PRIMUSr 880 Digital Weather Radar System
Under the right conditions, a dangerous thunder bumper can
D
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, 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.
At low altitude, the tilt should be set as low as possible to get ground
D
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.
Radar Facts
5-14

Fast Developing Thunderstorm

Figure 5- 14
WRONG

Low Altitude Tilt Management

Figure 5- 15
THUNDERSTORM MATURES
AS IT APPROACHES
FREEZING
LEVEL
AD- 35700@
A28- 1146- 102- 00
FREEZING
LEVEL
AD- 35699@