AIM
11/3/22
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15. 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.
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_insp
ectors/8400/fsat
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16. Avoid Flight in the Vicinity of
Exhaust Plumes (Smoke Stacks and
Cooling Towers)
a. Flight Hazards Exist Around Exhaust
Plumes.
Exhaust plumes are defined as visible or
invisible emissions from power plants, industrial
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Potential Flight Hazards