INTRODUCTION
Anti-icing equipment on Learjet SNs 23-003 through 24-180, and 25-002 through -024
not certified for flight in known icing conditions is provided and approved for engine
protection only. The wing anti-ice system should be operated in concurrence with
nacelle heat. Protection is provided on the following:
• Engine nacelle lip and engine front frame
• Windshield
• Wing leading edge (not certified for flight into known icing conditions)
The anti-icing equipment utilizes either electri-
cally heated units or engine bleed air. Windshield
alcohol is used for deicing. Rain removal is ac-
complished with bleed air by a service kit.
Engine bleed air is used to heat the windshields,
the wing leading edge, and the engine front
frame. The engine front frame includes the guide
vanes, variable guide vanes, and the nose cone.
Icing conditions exist if visible moisture is
present and the ram-air temperature (RAT) is
10ºC or lower. During daylight operation, ice
accumulation can be detected on the windshield
and on the wing leading edge, particularly where
the wing and tip tank join and on the tip tanks.
Figure 10A-1 illustrates the ice and rain pro-
tected areas.
CHAPTER 10A
ICE AND RAIN PROTECTION
10A-1
FOR TRAINING PURPOSES ONLY
LEARJET 20 SERIES PILOT TRAINING MANUAL
FlightSafety
international
GENERAL