SECTION 7
CESSNA
AIRPLANE & SYSTEMS DESCRIPTIONS
MODEL 172RG
the rudder incorporates a leading edge extension which contains a balance
weight. The horizontal stabilizer is constructed of a forward and aft spar,
ribs and stiffeners, center upper and lower skin panels, left and right upper
and lower skins panels, and formed leading edge skins. The horizontal
stabilizer also contains the elevator trim tab actuator. Construction of the
elevator consists of formed leading edge skins, a forward spar, ribs, torque
tube and bellcrank, left upper and lower "V" type corrugated skins, and
right upper and lower "V" type corrugated skins incorporating a trailing
edge cut-out for the trim tab. The elevator trim tab consists of a spar, rib
and upper and lower "V" type corrugated skins. Both elevator tip leading
edge extensions incorporate balance weights.
FLIGHT CONTROLS
The airplane's flight control system (see figure 7-1) consists of
conventional aileron, rudder, and elevator control surfaces. The control
surfaces are manually operated through mechanical linkage using a
control wheel for the ailerons and elevator, and rudder/brake pedals for
the rudder.
Extensions are available for the rudder/ brake pedals. They consist of a
rudder pedal face, two spacers and two spring clips. To install an exten-
sion, place the clip on the bottom of the extension under the bottom of the
rudder pedal and snap the top clip over the top of the rudder pedal. Check
that the extension is firmly in place. To remove the extensions, reverse the
above procedures.
TRIM SYSTEMS
Manually-operated rudder and elevator trim is provided (see figure 7-
1). Rudder trimming is accomplished through a bungee connected to the
rudder control system and a trim control wheel mounted on the control
pedestal. Rudder trimming is accomplished by rotating the horizontally
mounted trim control wheel either left or right to the desired trim position.
Rotating the trim wheel to the right will trim nose-right; conversely,
rotating it to the left will trim nose-left. Elevator trimming is accomp-
lished through the elevator trim tab by utilizing the vertically mounted
trim control wheel. Forward rotation of the trim wheel will trim nose-
down; conversely, aft rotation will trim nose-up.
INSTRUMENT PANEL
The instrument panel (see figure 7-2) is designed around the basic "T"
7
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1 July 1979
CESSNA
SECTION 7
MODEL 172RG
AIRPLANE & SYSTEMS DESCRIPTIONS
configuration. The gyros are located immediately in front of the pilot, and
arranged vertically. The airspeed indicator and altimeter are located to the
left and right of the gyros, respectively. The remaining flight instruments
are located around the basic "T". The fuel pressure gage, clock, fuel
quantity indicators, ammeter, oil pressure gage , oil temperature gage,
cylinder head temperature gage and low-voltage warning light are located
to the left of the flight instruments. Avionics equipment is stacked
approximately on the centerline of the panel, with the right side of the
panel containing the suction gage, economy mixture indicator (EGT),
flight hour recorder, and space for additional instruments and avionics
equipment. A switch and control panel, at the lower edge of the instrument
panel, contains most of the controls, switches, and circuit breakers
necessary to operate the airplane. The left side of the panel contains the
auxiliary fuel pump switch, engine primer, master switch, ignition switch,
general circuit breakers, electrical switches, landing gear indicator lights
and landing gear lever. The center area contains the static pressure
alternate source valve, and the carburetor heat, light intensity, throttle,
propeller, and mixture controls. The right side of the switch and control
panel contains the wing flap switch and position indicator, cabin heat and
cabin air controls, cigar lighter, and map compartment. A pedestal
extending from the switch and control panel to the floorboard, contains the
elevator and rudder trim control wheels, cowl flap control lever, and
microphone bracket. The fuel selector valve handle is located at the base of
the pedestal. A parking brake handle is mounted below the switch and
control panel in front of the pilot. The avionics power switch and avionics
circuit breakers are mounted on a small circuit breaker panel located
adjacent to the pilot on the left cabin sidewall.
For details concerning the instruments, switches, circuit breakers, and
controls on this panel, refer in this section to the description of the systems
to which these items are related.
GROUND CONTROL
Effective ground control while taxiing is accomplished through nose
wheel steering by using the rudder pedals; left rudder pedal to steer left and
right rudder pedal to steer right. When a rudder pedal is depressed, a
spring-loaded steering bungee (which is connected to the nose gear and to
the rudder bars) will turn the nose wheel through an arc of approximately
15° each side of center. By applying either left or right brake, the degree of
turn may be increased up to 30° each side of center.
Moving the airplane by hand is most easily accomplished by attaching
a tow bar to the nose gear strut. If a tow bar is not available, or pushing is
required, use the wing struts as push points. Do not use the vertical or
1 July 1979
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