Cessna 172 - Wing Flap System; Cabin Heating, Ventilating and Defrosting System

WING FLAP SYSTEM.
The wing flaps are electrically operated by a flap motor located in
the right wing. Flap position is controlled by a switch, labeled WING
FLAPS on the lower center portion of the instrument panel. · Flap posi-
tion is shown by an indicator on the lower right portion of the instrument
panel below the
right control wheel position.
ro extend the wing flaps, the flap switch must be depressed and held
in the DOWN position until the desired degree of · extension is reached: -·
Releasing the switch
allows it to return to the center off position. Normal
full flap extension in flight will require approximately 9. seconds. After
the flaps reach maximum extension or retraction, limit switches will
automatically shut off the flap motor .
. To
retract th_e flaps, place the flap switch in the UP position. The
switch will remafo in the UP position without manual 3:Ssistance. due to . an
ove· r-center design of the switch . . Full flap. retraction in flight requires
approximately 7- seconds.
More , gradual flap retraction - can be accom-
plished
by intermittent operation . of the flap· switch to the UP position.
After full
retraction, the switch is normally returned to the ceriter of( :,.,
pos~tion. . · · ·
CABIN HEATING, VENTILATING AND
DEFROSTING SYSTEM.
For cabin ventilation, pull the CABIN AIR knob out. To raise the air
temperature, pull the CABIN HT knob out approximately 1/4" to 1/2" for
a small amount of cabin heat. Additional heat is available by pulling the ·
.~ knob out' farther; maximum heat is available with the CABIN HT knob ..
j pulled out and the CABIN AIR knob pu· shed full in. When no heat is desired
~ in the cabin, the CABIN HT knob is pushed .full in.
j
Front cabin heat and ventilating air is supplied by outlet holes spaced
across a cabin manifold just forward of the pilot's and copilot's feet.
Rear cabin heat and.air is supplied by two ducts from the manifold, one
extending down each side of the cabin to an outlet at the front door post at
floor level. Windshield defrost air is also supplied by a duct leading from
the cabin manifold. Two knobs control sliding valves in the defroster out-
let and permit regulation of defroster airflow.
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