Textron Aviation Cessna 172S NAV III Skyhawk SP, Information Manual

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SECTION 3 CESSNA
EMERGENCY PROCEDURES MODEL 172S NAV III
KAP 140 AUTOPILOT
U.S.
ICING
INADVERTENT ICING ENCOUNTER DURING FLIGHT
1. PITOT HEAT Switch - ON
2. Turn back or change altitude (to obtain an outside air
temperature that is less conducive to icing)
3. CABIN HT Control Knob - ON (pull full out)
4. Defroster Control Outlets - OPEN (to obtain maximum
windshield defroster airflow)
5. CABIN AIR Control Knob - ADJUST (to obtain maximum
defroster heat and airflow)
6. Watch for signs of induction air filter icing. A loss of engine RPM
could be caused by ice blocking the air intake filter. Adjust the
throttle as necessary to hold engine RPM. Adjust mixture as
necessary for any change in power settings.
7. Plan a landing at the nearest airport. With an extremely rapid ice
build-up, select a suitable off airport landing site.
8. With an ice accumulation of 0.25 inch or more on the wing
leading edges, be prepared for significantly higher power
requirements, higher approach and stall speeds, and a longer
landing roll.
9. Leave wing flaps retracted. With a severe ice build-up on the
horizontal tail, the change in wing wake airflow direction caused
by wing flap extension could result in a loss of elevator
effectiveness.
10. Open left window and, if practical, scrape ice from a portion of
the windshield for visibility in the landing approach.
11. Perform a landing approach using a forward slip, if necessary,
for improved visibility.
12. Approach at 65 to 75 KIAS depending upon the amount of ice
accumulation.
13. Perform landing in level attitude.
14. Missed approaches should be avoided whenever possible
because of severely reduced climb capability.
172SPHAUS-05
3-14
For
Training
Purposes
Only