SECTION 3
CESSNA
EMERGENCY PROCEDURES
MODEL 172RG
control by monitoring the turn coordinator. Occasionally check the
compass heading and make minor corrections to hold an approximate
course. Before descending into the clouds, set up a stabilized let-down
condition as follows:
1.
Extend landing gear.
2.
Apply full rich mixture.
3.
Apply full carburetor heat.
4.
Reduce power to set up a 500 to 800 ft/min rate of descent.
5.
Adjust the elevator and rudder trim control wheels for a stabilized
descent at 80 KIAS.
6.
Keep hands off control wheel.
7.
Monitor turn coordinator and make corrections by rudder alone.
8.
Adjust rudder trim to relieve unbalanced rudder force, if present.
9.
Check trend of compass card movement and make cautious
corrections with rudder to stop turn.
10.
Upon breaking out of clouds, resume normal cruising flight.
RECOVERY FROM A SPIRAL DIVE
If a spiral is encountered, proceed as follows:
1.
Close the throttle.
2.
Stop the turn by using coordinated aileron and rudder control to
align the symbolic airplane in the turn coordinator with the
horizon reference line.
3.
Cautiously apply elevator back pressure to slowly reduce the
indicated airspeed to 80 KIAS.
4.
Adjust the elevator trim control to maintain an 80 KIAS glide.
5.
Keep hands off the control wheel, using rudder control to hold a
straight heading. Use rudder trim to relieve unbalanced rudder
force, if present.
6.
Apply carburetor heat.
7.
Clear engine occasionally, but avoid using enough power to
disturb the trimmed glide.
8.
Upon breaking out of clouds, resume normal cruising flight.
I NADVERTENT FLIGHT INTO ICING CONDITIONS
Flight into icing conditions is prohibited. An inadvertent encounter
with these conditions can best be handled using the checklist procedures.
The best procedure, of course, is to turn back or change altitude to escape
icing conditions.
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1 July 1979
CESSNA
SECTION 3
MODEL 172RG
EMERGENCY PROCEDURES
STATIC SOURCE BLOCKED
If erroneous readings of the static source instruments (airspeed,
altimeter and vertical speed) are suspected, the alternate static source
valve should be pulled on, thereby supplying static pressure to these
instruments from the cabin. Cabin pressures will vary with open ventila-
tors or windows and with airspeed. To avoid the possibility of large errors,
the windows should not be open when using the alternate static source.
NOTE
In an emergency on airplanes not equipped with an
alternate static source, cabin pressure can be supplied to
the static pressure instruments by breaking the glass in
the face of the vertical speed indicator.
A calibration table is provided in Section 5 to illustrate the effect of the
alternate static source on indicated airspeeds. With the windows closed
and the heater and defroster full on, the airspeed indicator may typically
read as much as 3 knots slower and the altimeter 35 feet lower in cruise. If
the alternate static source must be used for landing, the normal indicated
approach speed may be used since the indicated airspeed variations in this
configuration are 2 knots or less.
SPINS
Intentional spins are prohibited in this airplane. Should an inadvert-
ent spin occur, the following recovery procedure should be used:
1.
RETARD THROTTLE TO IDLE POSITION.
2.
PLACE AILERONS IN NEUTRAL POSITION.
3.
APPLY AND HOLD FULL RUDDER OPPOSITE TO THE DIREC-
TION OF ROTATION.
4.
JUST AFTER THE RUDDER REACHES THE STOP, MOVE THE
WHEEL BRISKLY FORWARD FAR ENOUGH TO BREAK THE
STALL. Full down elevator may be required at aft center of gravity
loadings to assure optimum recoveries.
5.
HOLD THESE CONTROL INPUTS UNTIL ROTATION STOPS
Premature relaxation of the control inputs may extend the recov-
ery.
6.
AS ROTATION STOPS, NEUTRALIZE RUDDER, AND MAKE A
SMOOTH RECOVERY FROM THE RESULTING DIVE.
NOTE
If disorientation precludes a visual determination of the
1 July 1979
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