King Air C90GTi, Pilot Training Manual

Page: 236 / 557

WING ICE LIGHTS
Wi n g i c e l i g h t s a r e p r ov i d e d t o l i g h t t h e
w i n g l e a d i n g e d g e s t o d e t e r m i n e i c e
buildup in icing conditions. The wing lights
a r e l o c a t e d o n t h e o u t b o a r d s i d e o f e a c h
nacelle. The circuit-breaker switch is lo-
c a t e d o n t h e p i l o t ’s ri g h t s u b p a n e l i n t h e
L I G H T S g r o u p a b ove t h e I C E p r o t e c t i o n
g roup (Figure 10-19).
The wing ice lights should be used as re-
quired in night flight to check for wing ice
accumulation. The wing ice lights operate
at a high temperature and therefore should
not be used for prolonged periods while the
air plane is on the g round. All ice lights in-
stalled must be operational for flights into
known or forecast icing conditions at night.
PRECAUTIONS DURING ICING
CONDITIONS
There are some precautions which prevail
during winter or icing conditions. An air-
plane needs special care and inspection be-
f o r e o p e r a t i o n i n c o l d o r p o t e n t i a l i c i n g
weather. In addition to the normal exterior
inspection, special attention should be paid
to areas where frost and ice may accumulate.
Pilots should be familiar with the potential
har m a har mless-looking, thin layer of frost
can cause. It is not the thickness of the frost
that matters; it is the texture. A slightly ir-
regular surface can substantially decrease
proper airflow over the wings and stabiliz-
ers. Never underestimate the damaging ef-
fects of frost. All frost should be removed
from the leading edges of the wings, sta-
bilons, stabilizers, and propellers before the
air plane is moved.
Control surf aces, hinges, the windshield,
pitot masts, fuel tank caps, and vents should
also be free of frost. Deicing fluid should
be used when needed.
Fuel drains should be tested for free flow.
Water in the fuel system has a tendency to
c o n d e n s e m o r e r e a d i l y d u r i n g w i n t e r
months, and if left unchecked, large amounts
of moisture may accumulate in the fuel tanks.
Moisture does not always settle at the bot-
tom of the tank. Occasionally a thin layer of
fuel gets trapped under a large mass of water,
which may deceive the tester. Make sure a
good-sized sample of fuel is taken.
It is also impor tant to add only the cor rect
amount of anti-icing additive to the fuel. A
higher concentration of anti-icer does not
ensure lower fuel freezing temperatures and
m ay h i n d e r t h e a i r p l a n e ’s p e r f o r m a n c e .
Consult the “Nor mal Procedures” section
of the
Pilot’s Operating Handbook to de-
ter mine the cor rect blend.
KING AIR C90GTi/C90GTx PILOT TRAINING MANUAL
10-17
FOR TRAINING PURPOSES ONLY
10
ICE
AND
RAIN
PRO
TECTION
Figure 10-19. Wing Anti-Ice Lights