1. True Airspeed Indicator
2. Static/True Air Temperature Indicator
3. Front Panel Dimming Control
4. True Air Temperature Push Button
Figure 3C-21. True Airspeed/Static/True Air Temperature/True Air Temperature Indicator
(3) DIM Knob Front panel-dimming control.
(4) TAT Button Momentary push button
when pressed changes SAT to TAT.
Section IV. RADAR AND TRANSPONDER
3C-34. RADAR SYSTEM.
a. Description. The Honeywell Primus 300SL
color radar system is a lightweight, X-band digital
radar with alphanumerics designed for weather
detection and analysis and ground mapping.
The primary purpose of the system is to detect
storms along the flight path and give the pilot a visual
indication in color of the rainfall intensity. After proper
evaluation, the pilot can chart a course to avoid these
The system performs only the function of
weather detection or ground mapping. It
should not be used, nor relied upon, for
Do not operate radar system, even in
STANDBY Mode, without 115-Vac, 400-Hz
power applied to the system.
Without ac power, the receiver-transmitter-
cooling blower will not operate, which
could result in circuit damage and/or
In weather detection mode, storm intensity levels
are displayed in three bright colors contrasted against
a deep black background. Areas of heaviest rainfall
will appear in red, less severe rainfall in yellow,
moderate rainfall in green, and little or no rainfall in
displayed in cyan, are provided to facilitate evaluation
of storm cells. The cyclic function further emphasizes
the heavy rainfall areas (red) of the weather display by
flashing them approximately once per second.