BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.

GUIDELINE TOPICS  SUMMARY OF GUIDELINES 
-- SNOW, ICE OR FROST REMOVAL/PROTECTION METHOD UNHEATED WATER  34°F OR ABOVE TEMP STABLE OR RISING -ACCEPTABLE METHOD FOR REMOVING SNOW FROM SURFACES IN HANGAR OR OUTSIDE. ANTI-ICING FLUID APPLICATION OPTIONAL  27°F TO 34°F TEMP STABLE OR RISING- NOT PERMITTED   BELOW 27°F - NOT PERMITTED 

- HOT WATER DEICING  - ACCEPTABLE AS ICE, SNOW  -  RECOMMENDED  -  NOT PERMITTED 
(180-200°F AT TANK)  OR FROST REMOVAL METHOD  METHOD FOR ICE, SNOW 
FOLLOWED BY ANTI-ICING  IN HANGAR OR OUTSIDE.  OR FROST REMOVAL IN 
APPLICATION  ANTI-ICING FLUID OPTIONAL  HANGAR OR OUTSIDE 

- DEICING (180-200°F AT TANK)  - NOT RECOMMENDED (USE OF COSTLY FLUID ABOVE FREEZING NOT JUSTIFIED)  -  ACCEPTABLE METHOD FOR ICE, SNOW OR FROST REMOVAL OUTSIDE  -  RECOMMENDED METHOD FOR ICE, SNOW OR FROST REMOVAL OUTSIDE 
- ANTI-ICING FLUID  - NOT REQUIRED  - APPLY IF HOT WATER METHOD USED  - APPLY AS PROTECTION IF ICE, SNOW OR FROST CONDITION ANTICIPATED 
- APPLY AS PROTECTION  -  REAPPLY AS 
TO MINIMIZE ICE, SNOW OR FROST  NECESSARY AFTER DEICING 
ACCUMULATION 
- REAPPLY AS 
NECESSARY AFTER 
DEICING 

APU - MAY OPERATE WHEN DEICING BUT OBSERVE PRECAUTIONS.
WARNING:  BECAUSE OF EXTREME DANGER TO PERSONNEL NEAR APU INLET AND EXHAUST WHEN APU IS OPERATING, DANGER ZONE DEFINED IN CHAPTER 10 MUST BE OBSERVED.
ENGINES - DO NOT OPERATE WHILE DEICING IF POSSIBLE.
- IF THE ENGINE MUST OPERATE WHILE DEICING, OBSERVE PRECAUTIONS.
WARNING: BECAUSE OF EXTREME DANGER TO PERSONNEL NEAR ENGINE INLET AND EXHAUST WHEN ENGINE IS OPERATING, DANGER ZONE DEFINED IN CHAPTER 10 MUST BE OBSERVED.
PRECAUTIONS - DO NOT RELEASE AIRPLANE FOR TAKEOFF WITH ICE, SNOW OR FROST ON CONTROL, WING OR HORIZONTAL TAIL SURFACES EXCEPT FOR A MAXIMUM OF 1/8-INCH FROST ON LOWER WING SURFACE BETWEEN SPARS.
-
FUSELAGE AND VERTICAL TAIL SURFACES SHOULD BE FREE FROM ICE AND SNOW. THIN HOAR FROST IS PERMISSIBLE ON THE UPPER FUSELAGE.

-
 DO NOT SPRAY ANTI-ICING/DEICING FLUID DIRECTLY INTO ENGINE OR APU INLETS, EXHAUSTS, ENGINE THRUST REVERSERS, PROBE INLETS, SCOOPS, VENTS, DRAINS, ETC.

-
 DO NOT SPRAY HOT FLUID DIRECTLY ON COLD WINDOWS.

-
 DO NOT FORCE ICE OR SNOW INTO OPENINGS AROUND FLIGHT CONTROL SURFACES DURING REMOVAL PROCEDURE.

-
DO NOT CLOSE ANY DOOR UNTIL ALL ICE OR SNOW HAS BEEN REMOVED WITH DEICING FLUID.

- CLOSE CABIN AIR CONDITIONING PACK VALVES AND BLEED VALVES IF ENGINES OR APU IS RUNNING. OPERATING - CHECK ALL CONTROL SURFACE OPERATION BY CYCLING. GROUND OBSERVER SHOULD VERIFY
INSPECTION  FULL TRAVEL. IF THERE IS REASON TO SUSPECT FROZEN SEALS OR OBSTRUCTIONS, OPERATE SURFACES MANUALLY BEFORE APPLYING POWER.
-
CHECK THAT PITOT AND STATIC OPENINGS ARE FREE OF OBSTRUCTION WITHIN 4 FEET.

-
CHECK THAT LANDING GEAR AND WHEEL WELL AREA ARE FREE FROM ICE, SNOW, AND SLUSH.

-
CHECK THAT ALL INLETS AND EXHAUSTS ARE UNOBSTRUCTED.

-
CHECK THAT ALL DRAINS ARE FREE FROM OBSTRUCTIONS.

-
CHECK THAT ANGLE OF AIRFLOW SENSORS ARE FREE OF ICE AND/OR SNOW AND THAT SENSORS MOVE FREELY.

500  Guidelines Summary: Ice, Snow or Frost Conditions 
Feb 01/95  Figure 202  12-50-0 
Page 219 
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details. 

Horizontal Stabilizer Position  500 
12-50-0Page 220   Figure 203 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  Feb 20/93 

500  Balance Panel and Probe Location 
Feb 20/93  Figure 204 BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.  12-50-0 Page 221