Learjet 35A - Page 128

111.111 _ .... al
ANTI-ICE SYSTEMS (CONT)
• Aircraft 35-107, 35-113 & Subsequent incorporating
AMK
91-2. Aircraft 36-032 & Subsequent incorporating
AMK91-2.
The WSHLD HT switch has three positions labeled ON, HOLD, OFF. In
the OFF position, no windshield airflow is available. In the ON position, the
control valve is fully open allowing maximum airflow to the windshield. The
HOLD position is used to stop the control valve in any position between ful-
ly closed and fully open. If a change in airflow is desired, set switch to OFF
or ON until desired airflow is obtained then set switch to HOLD. Illumina-
tion of
the red WSHLD OV HT light indicates a windshield heat system
failure.
TO AcnvATE THE SYSTEM:
1. WSHLD HT Switch - ON. The green WSHLD HT light will illumi-
nate.
E~
The overheat shutoff valve may cycle to prevent over-
heating of
the windshield. When the overheat shutoff
valve cycles closed, the green WSHLD
I-IT light will ex-
tinguish.
The system will automatically reset (green
WSHLD
HT light will illuminate) after the system cools.
2. To reduce
flow in the event of excessive noise or system cycling:
WSHLD
HT Switch - OFF until flow is acceptable, then HOLD.
IF WSHLD OV HT UGI-IT ILLUMINATES:
1. WSHLD HT Switch - OFF until red WSHLD OV HT light extin-
guishes,
then HOLD.
TO DEAcnvATE THE SYSTEM:
1. WSHLD HT Switch - OFF.
IF AIRFLOW SHOULD FAIL
The pilot's windshield may be anti-iced by the following:
1. WSHLDIRADOME-RAD Switch - WSHLDIRADOME. This will
anti-ice the radome and pilot's windshield and give alcohol fbw for
apprOximately
45 minutes. The amber ALe AI light will illuminate
when alcohol
level is low.
2.
WSHLDIRADOME-RAD Switch - OFF when alcohol is depleted
or clear of icing conditions.
FAA APPROVED 4-30-76
REISSUED 2-25-81, CHANGE 10
2-71