Recovery From Spiral Dive In The Clouds (Ahrs Failed); Inadvertent Flight Into Icing Conditions - Cessna SkyHawk SP 172S Operating Handbook

CESSNA
MODEL 172S NAV Ill
GFC 700 AFCS
SECTION 3
EMERGENCY PROCEDURES
EMERGENCY OPERATION IN CLOUDS
(Continued)
RECOVERY FROM SPIRAL DIVE IN THE CLOUDS (AHRS
FAILED)
AHRS FAILURE
If a spiral is entered while in the clouds, continue as follows:
1. Retard throttle to idle position.
2. Remove feet from rudder pedals.
3. Stop turn by carefully leveling the wings using aileron control to
align the roll index and roll pointer of the standby attitude
indicator.
4. Cautiously apply elevator back pressure to slowly reduce the
airspeed to 80 KIAS.
5. Adjust the elevator trim control to maintain an 80 KIAS glide.
6. Use aileron control to maintain wings level (keep roll pointer and
index aligned) and constant heading.
7. Resume Emergency Descent Through The Clouds procedure.
8. Upon breaking out of clouds, resume normal cruising flight.
INADVERTENT FLIGHT INTO ICING CONDITIONS
Flight into icing conditions is prohibited and extremely dangerous. An
inadvertent encounter with these conditions can be resolved using the
checklist procedures. The best action is to turn back or change altitude
to escape icing conditions. Set the PITOT HEAT switch to the ON
position until safely out of icing conditions.
During these encounters, an unexplained loss of engine power could
be caused by ice blocking the air intake filter or in extremely rare
instances ice completely blocking the fuel injection air reference tubes.
In either case, the throttle should be positioned to obtain maximum
RPM (in some instances, the throttle may need to be retarded for
maximum power). The mixture should then be adjusted, as required, to
obtain maximum RPM.
172SPHBUS-OO
U.S.
3-31