Cessna 177 SERIES Service Manual

14-7. DEFROSTER SYSTEM. lators mounted in the overhead console, two adjust-
able ventilators
mounted in the
aft wing root areas
14-8. DESCRIPTION.
The defrosting system is com-
and flexible ducting connecting the system.
prised of a duct across the aft side of the firewall, a
defroster
outlet, mounted
on the left side of the cowl
14-14. OPERATION.
Ram air received
from scoops
deck immediately aft
of the windshield, a control
mounted
in the inboard leading
edges of the wings is
knob
on the instrument panel
and flexible ducting
con- ducted to small
plenum chambers,
located at each
necting the system.
wing root
rib. From the plenum
chambers the air is
routed to the pilot and
copilot overhead console
out-
14-9. OPERATION. Air from the duct across the lets and to the rear seat outlets. On some aircraft
aft side of the firewall flows through a flexible
duct the quantity of air flowing through
the outlets is con-
to the
defroster outlet. The defroster control oper-
trolled by means of a geared-type control,
actuated by
ates a damper in the firewall
duct outlet to regulate rotating a knob
at each outlet position. (Refer to fig-
the amount of air deflected across the inside surface ure 14-2, sheet 1.) On other aircraft the quantity of
of the windshield. The temperature and volume
of air is controlled by means of
a 360 degree manually-
this air is controlled by the settings of the cabin operated swiveling valve which can be turned to in-
heating system control. crease, decrease and direct the flow of air wherever
desired.
(Refer to figure
14-2, sheets 2 and
3.)
14-10. TROUBLE SHOOTING. Since the defrosting
system depends on proper operation of the
heating 14-15. TROUBLE SHOOTING.
Most of the oper-
systems.
refer to paragraph 14-5 for trouble shoot-
ational troubles in the ventilating system
are caused
ing the heating and defrosting systems.
by sticking or binding air valves
and their controls
or damaged
air
ducting. In
most cases,
air valves
14-11. REMOVAL, REPAIR AND INSTALLATION. or controls can be freed by proper lubrication. Dam-
Figure 14-1 illustrates the defrosting
system and aged or broken parts
should be repaired or replaced.
may be used as a guide for removal, installation
and When checking rigging of controls,
ensure valves
repair of defroster system components.
Burned, respond freely to control
movement, that they move
frayed or crushed hose
should be replaced with new in the correct
direction and that they move through
hose, cut to length
and installed in the
original rout-
their full range of travel
and seal properly.
ing. Trim hose winding shorter than the hose to I
allow clamps to be fitted.
A defective defroster
out- 14-16. REMOVAL,
REPAIR AND
INSTALLATION. |
let must be repaired or replaced.
Figure 14-2 illustrates
the ventilating system and
may be used as
a guide for removal,
installation
14-12. VENTILATING SYSTEM. and repair of the ventilating system components.
Frayed or crushed hose should be replaced with new
i4-13.
DESCRIPTION. The ventilating system is
hose, cut to length and installed in the
original rout-
comprised of
an airscoop mounted in the inboard
ing. Trim hose winding shorter than the hose
to
leading
edge of each wing, a small plenum chamber
allow clamps to be fitted. Defective air
valves must
mounted at each wing
root rib, two adjustable
venti- be repaired
or replaced. Check
for proper operation
of valves and controls after repair or replacement.
SHOP
NOTES:
14-6 Change 7

Cessna 177 SERIES Specifications

General

Manufacturer	Cessna
Engine Type	Piston
Wingspan	35 ft 6 in (10.82 m)
Seating Capacity	4
Number Built	4, 295
Engine	Lycoming O-360
Horsepower	180 hp
Maximum Takeoff Weight	2, 500 lb (1, 134 kg)