6/17/21 

AIM 

l.  Glaciers. 

Be conscious of your altitude when 

flying over glaciers. The glaciers may be rising faster 
than you are climbing. 

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6

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14.  Operations in Ground Icing 

Conditions 

a. 

The presence of aircraft airframe icing during 

takeoff, typically caused by improper or no deicing of 
the aircraft being accomplished prior to flight has 
contributed to many recent accidents in turbine 
aircraft. The General Aviation Joint Steering 
Committee (GAJSC) is the primary vehicle for 
government

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industry cooperation, communication, 

and coordination on GA accident mitigation. The 
Turbine Aircraft Operations Subgroup (TAOS) 
works to mitigate accidents in turbine accident 
aviation. While there is sufficient information and 
guidance currently available regarding the effects of 
icing on aircraft and methods for deicing, the TAOS 
has developed a list of recommended actions to 
further assist pilots and operators in this area. 

While the efforts of the TAOS specifically focus on 
turbine aircraft, it is recognized that their recommen-
dations are applicable to and can be adapted for the 
pilot of a small, piston powered aircraft too. 

b. 

The following recommendations are offered: 

1. 

Ensure that your aircraft’s lift

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generating 

surfaces are COMPLETELY free of contamination 
before flight through a tactile (hands on) check of the 
critical surfaces when feasible. Even when otherwise 
permitted, operators should avoid smooth or polished 
frost on lift

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generating surfaces as an acceptable 

preflight condition. 

2. 

Review and refresh your cold weather 

standard operating procedures. 

3. 

Review and be familiar with the Airplane 

Flight Manual (AFM) limitations and procedures 
necessary to deal with icing conditions prior to flight, 
as well as in flight. 

4. 

Protect your aircraft while on the ground, if 

possible, from sleet and freezing rain by taking 
advantage of aircraft hangars. 

5. 

Take full advantage of the opportunities 

available at airports for deicing. Do not refuse deicing 
services simply because of cost. 

6. 

Always consider canceling or delaying a 

flight if weather conditions do not support a safe 
operation. 

c. 

If you haven’t already developed a set of 

Standard Operating Procedures for cold weather 
operations, they should include: 

1. 

Procedures based on information that is 

applicable to the aircraft operated, such as AFM 
limitations and procedures; 

2. 

Concise and easy to understand guidance that 

outlines best operational practices; 

3. 

A systematic procedure for recognizing, 

evaluating and addressing the associated icing risk, 
and offer clear guidance to mitigate this risk; 

4. 

An aid (such as a checklist or reference cards) 

that is readily available during normal day

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to

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day 

aircraft operations. 

d. 

There are several sources for guidance relating 

to airframe icing, including: 

1. 

http://aircrafticing.grc.nasa.gov/index.html 

2. 

http://www.ibac.org/is

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bao/isbao.htm 

3. 

http://www.natasafety1st.org/bus_deice.htm 

4. 

Advisory Circular (AC) 91

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74, Pilot Guide, 

Flight in Icing Conditions. 

5. 

AC 135

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17, Pilot Guide Small Aircraft 

Ground Deicing. 

6. 

AC 135

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9, FAR Part 135 Icing Limitations. 

7. 

AC 120

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60, Ground Deicing and Anti

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icing 

Program. 

8. 

AC 135

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16, Ground Deicing and Anti

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icing 

Training and Checking. 

The FAA Approved Deicing Program Updates is 
published annually as a Flight Standards Information 
Bulletin for Air Transportation and contains detailed 
information on deicing and anti

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icing procedures and 

holdover times. It may be accessed at the following 
website by selecting the current year’s information 
bulletins: 

http://www.faa.gov/library/manuals/examiners_inspe 
ctors/8400/fsat 

Potential Flight Hazards 

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