SAMPLE/PRELIMINARY.
CREWMEMBER TRAINING
ANTI-ICE/DEICE PROCEDURES
May 2007
SAMPLE/PRELIMINARY.
DEICING TRAINING
May 2007
Page i
TABLE OF CONTENTS
Cover Sheet
Table of Contents ..........................................
DEICE/ANTI-ICE TRAINING PROGRAM
I.
FARS's relating to operations in ground icing conditions ...
II.
Preflight procedures during ground icing conditions ........
III.
Pre-takeoff contamination check ............................
IV.
Types of aircraft surface contamination ....................
V.
Effects of frost, ice and snow on aircraft control .........
VI.
Methods of deicing .........................................
VII.
Types and characteristics of deice fluids ..................
VIII.
Safety precautions when using deice fluids .................
IX.
Holdover times - Definition.................................
X.
Communication ..............................................
XI.
Holdover fluids, Limitations/Loss of Effectiveness..........
XII.
Removal of contaminations - With/without fluids.............
XIII.
Company Policy .............................................
XIV.
Type fluid approved for each aircraft ......................
XV.
DE/ANTI-ICE WORKSHEET .....................................
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SAMPLE/PRELIMINARY.
I.
DEICING TRAINING
May 2007
Page 1
FAR'S RELATING TO OPERATIONS IN GROUND ICING CONDITIONS
FAR 135.227:
a) No pilot may take off an aircraft that has frost, snow, or ice
adhering to any rotor blade, propeller, windshield, wing,
stabilizing or control surface, to a powerplant installation, or to
an airspeed, altimeter, rate of climb, or flight attitude
instrument system, except under the following conditions:
(1) Takeoffs may be made with frost adhering to the wings, or
stabilizing or control surfaces, if the frost has been polished to
make it smooth.
(2) Takeoffs may be made with frost under the wing in the area of the
fuel tanks if authorized by the administrator.
b) No certificate holder may authorize an airplane to takeoff and no pilot
may take off an airplane any time conditions are such that frost, ice, or
snow may reasonably be expected to adhere to the airplane unless the pilot
has completed all applicable training requirements of 135.341 and unless
one of the following requirements is met:
(1)
A pre-takeoff contamination check, that has been established by the
certificate holder and approved by the administrator for the
specific airplane type, has been completed within five minutes prior
to takeoff. A pretakeoff contamination check is a check to make
sure the wings and control surfaces are free of frost, ice, or snow.
(2) The certificate holder has an approved alternate procedure and under
that procedure the airplane is determined to be free of frost, ice
or snow.
(3) The certificate holder has an approved deicing/anti-icing program
that complies with 121.629(c)of this chapter and the takeoff
complies with that program.
(Sample does not have a procedure to comply with (2)above, or a program to
comply with (3). Therefore, the pre-takeoff contamination check on page 4 must
be followed by all pilots when operating in ground icing conditions. Holdover
Tables to be used when a Deice/Anti-ice facility is performing the contamination
removal under Sample Company’s program must be included in Sample’s Company
Manual and located in each aircraft.)
Some aircraft manufacturers have published specific deice procedures. Any company
deice program will need to use any manufacturer specific deice Procedures when
deicing that make or make/model airplane. If a manufacturer has not published
specific deice procedures, the generic aircraft deice procedures located in the
current copy of AC 135-16 must be used to deice an aircraft.
SAMPLE/PRELIMINARY.
II.
DEICING TRAINING
May 2007
Page 2
PREFLIGHT PROCEDURES DURING GROUND ICING CONDITIONS
It is natural that as the temperature drops so does the amount of time that
is spent on a thorough preflight inspection.
However, these are the
conditions when even more time should be spent on the preflight, paying
particular attention to any signs of ice, snow, or frost adhering to:
(1)
(2)
(3)
(4)
(5)
(6)
(7)
(8)
(9)
(10)
(11)
(12)
(13)
(14)
The wing leading edges, upper and lower surfaces.
The vertical and horizontal stabilizing devices upper and lower
surfaces, leading edges and side panels.
NOTE: It is not possible to see the top to the horizontal
stabilizer on all aircraft during preflight. In
those cases, use the condition of the upper surface
of the wing as an indicator of the condition of the
horizontal stab.
Flaps.
Spoilers or speed brakes, if installed.
All control surfaces.
Propellers, if installed.
Engine inlets.
Windshields and windows necessary for visibility.
Antennas.
Fuselage.
Exposed instrumentation devices - pitot tubes and static ports.
Fuel cap and fuel tank vents.
Cooling air intakes.
Landing gear.
If the aircraft has been exposed to blowing snow, special attention should
be given to openings in the aircraft where snow can enter, freeze and
obstruct normal operation such as:
(1) Pitot tubes and static systems sensing ports.
(2) Wheel wells.
(3) Heater inlets.
(4) Engine inlets.
(5) Elevators and rudder controls.
(6) Fuel vents.
III.
PRE-TAKEOFF CONTAMINATION CHECK
During operations in ground icing conditions it is the PIC's responsibility
to assure that the aircraft is free of ice contamination prior to takeoff.
The pre-takeoff contamination check must be completed prior to takeoff.
This shall be accomplished by the PIC (or the SIC at the PIC's direction).
He shall conduct a walk around of the aircraft to visually check the
aircraft wings and control surfaces for contamination. If takeoff is not
accomplished within five minutes of completion of the check, or icing
conditions began after engine start, succeeding checks for contamination may
be accomplished from the cockpit by looking at that portion of the wing which is
visible from the cockpit and not affected by abnormal influence such as engine
exhaust on a turboprop aircraft. At night, a flashlight or wing inspection light
must be used to illuminate the wing area.
SAMPLE/PRELIMINARY.
IV.
DEICING TRAINING
May 2007
Page 3
TYPES OF AIRCRAFT SURFACE CONTAMINATION
Aircraft surface contamination may appear in any of the following forms:
(1) FREEZING PRECIPITATION - snow, sleet, or freezing rain that adheres
to the aircraft surfaces.
FREEZING RAIN - Rain condensed from atmospheric vapor falling to
earth in supercooled drops, forming ice on objects.
(2) HIGH RELATIVE HUMIDITY - Conditions that may produce frost formations
on aircraft surfaces having a temperature at or below the dew or frost
point. Frost accumulations are common during overnight ground storage and
after landing where aircraft surface temperatures remain cold following
descent from higher altitudes. This is a common occurrence on lower wing
surfaces in the vicinity of the fuel cells.
Frost and other ice
formations can also occur or upper wing surfaces in contact with cold
fuel.
On some aircraft clear ice formations can occur that are difficult
to detect.
(3) FROST - a crystallized deposit formed by water vapor on surfaces which
are at or below 0˚C/32˚F and Hoarfrost - which is white frozen dew.
UNDER WING FROST - frost caused by cold soaked fuel in the area of the
fuel tanks. Underwing frost formations do not generally influence
aircraft performance and flight characteristics as severely as leading
edge and upper wing frost.
POLISHED FROST - it is permissible to takeoff with frost formations
on the wing surfaces if the frost is polished smooth.
ACTIVE FROST - is a frost condition that is actively growing crystals
and gaining in mass and thickness and is considered a precipitation
condition. It typically forms at night under clear skies and calm
winds when the OAT is below 0˚C/32˚F and the dew point temperature
spread is less than 3˚C. The temperature of the aircraft surface must
be at or below 0˚C/32˚F and at or below dew point.
As an example, if
an aircraft is parked outdoors on a cold clear night, heat can radiate
from its surface at a rate greater than is absorbed from its
surroundings. The net effect is that the aircraft surface temperature
drops below the OAT. If this temperature is below the frost point
temperature of the air, moisture will deposit in the form of hoarfrost.
As a guide, if there is frost on any object in the deicing area
including the aircraft, and the OAT and dew point are 3˚C apart and
narrowing, there is likely to be active frost.
If the OAT and dew
point are 3˚ apart and expanding, it not clear is there is active
frost. Therefore, if there is doubt, the condition should be treated
as active frost.
Weather forecasts and METARS usually do not provide
information on frost conditions.
HOARFROST - thin hoarfrost is acceptable on the upper surface of the
aircraft fuselage provided all vents and ports are clear. This
hoarfrost is usually a uniform white deposit of fine crystalline
texture as indicated above, and it thin enough to allow one to visually
distinguish aircraft paint surface features underneath it, such as
paint lines, markings and lettering.
SAMPLE/PRELIMINARY.
DEICING TRAINING
May 2007
Page 4
(4) FREEZING FOG - Clouds of supercooled water deposits that form a deposit
of ice on objects in cold water. The freezing fog condition is best
confirmed by observation. If there is accumulation in the deicing area,
then the condition is active and there is a tendency for freezing fog
accumulation to increase with increasing wind speed. The least
accumulation occurs with zero wind. Higher accumulations are possible with
higher winds. Fluid performance can be affected by wind, but this factor is
not accommodated for when generating fluid holdover times. Freezing fog
can accumulate on aircraft surfaces during taxi, since taxi speed has a
similar effect as wind speed.
(5) SNOW - Precipitation in the form of small ice crystals or flakes which
may accumulate or adhere to the aircraft surfaces.
BLOWING SNOW - snow blown by ambient winds, other aircraft or ground
support equipment from snow drifts, other aircraft, buildings, or other
ground structures.
RECIRCULATED SNOW - snow made airborne by engine or propeller wash, or by
reverse operation of thrust reversers or reverse pitch propellers.
SNOW GRAINS - are partially rimed and usually comprise the general
makeup of snow. Typically less than 1mm in diameter with a density of
less than 0.5 gm/cc and do not bounce when impacting a hard surface.
SNOW/ICE PELLETS - bounce upon impacting a hard surface.
(6) CLEAR ICE PHENOMENA - Some aircraft have experienced formations of clear
ice on the upper surfaces of wings in the vicinity of integral fuel tanks.
Such ice is difficult to see and in many instances cannot be detected other
than by touch with the bare hand or by means of a special purpose ice
detector.
These phenomena typically occur on aircraft that have flown at
a high altitude for a sufficient time to cold soak fuel in integral tanks,
and the fuel remaining in these tanks, after landing, is sufficient to
contact upper wing skins causing clear ice to form when rain drizzle,
wet snow or high humidity is present - at, above, or below freezing
ambient temperature.
(7) RESIDUAL ICE FROM A PREVIOUS FLIGHT - Some contaminants may exist on
leading edges of wings, empennage, trailing edge flaps, elevator cavities
and other surfaces.
OPERATION ON RAMPS, TAXIWAYS AND RUNWAYS CONTAINING MOISTURE,SLUSH, OR
SNOW - Residual ice or slush accumulated on airframe components during
landing and taxi operations on contaminated runways, taxiways and ramps
can remain in place if low temperatures and other weather conditions
exist unless identified and removed. Contaminants of this type are commonly
found in wheel wells, on landing gear components, trailing edge flaps,
under surfaces of wings and horizontal stabilizers, and other components.
SAMPLE/PRELIMINARY.
V.
DEICING TRAINING
May 2007
Page 5
EFFECTS OF FROST, ICE AND SNOW ON AIRCRAFT CONTROL
Tests have proven that frost or ice having even the roughness of medium or course
sand paper on the upper surface of the wing can reduce wing lift as much as 30%
and increase drag as much as 40%.
Changes in lift and drag significantly increase stall speed, reduce
cntrollability, and alter aircraft flight characteristics.
Thicker or rougher
frozen contaminants can have increasing adverse effects on lift, drag, stall
speed, stability and control and aircraft performance with the primary influence
being surface roughness located on critical portions of an aerodynamic surface.
These adverse effects on the aerodynamic properties of the airfoil may result in
sudden departure from the commanded flight path and may not be preceded by any
indications or aerodynamic warning to the pilot. Therefore, it is imperative that
takeoff not be attempted unless the PIC has made certain that the critical
surfaces and components of the aircraft are free of adhering ice, snow, or frost
formations.
Snow, frost, slush and other ice formations on other components of the aircraft
can cause undesirable local airflow disturbances, or restrictions of air and fluid
vents. They can cause mechanical interference and restricted movement of flight
controls, flap, speed brake, landing gear retraction, and other mechanisms
necessary for safe flight.
Ice formations on turbine engines and carburetor air intakes can cause a power
loss, and if dislodged and ingested into the engine, can cause engine damage
and/or failure.
Ice formations on external instrumentation sensors, such as pitot/static ports,
and angle of attack sensors can cause improper indications or improper operation
of certain systems and components that may be critical to safe flight.
In addition to lost of lift and increased drag - ice, snow, or frost adhering to
the airplane can also cause:
 Increased weight.
 Increased drag.
 Increased stall speed and power required to achieve or sustain flight.
 Decreased Performance.
 Decreased effectiveness of the flight controls.
 Decreased stall angle of attack.
 Power available may be decreased.
 Stall can occur before activation of the stall warning system.
 A rapid pitch tendency during rotation or wing roll off.
 Trim effectiveness may deteriorate.
 Engine loss due to ice FOD.
 Asymmetric shuddering due to props shedding ice.
 Control surfaces may freeze in place.
 Wing flaps can be damaged in the effort to retract or extend them in
icing conditions
 Landing gear mechanism may freeze in place or be damaged by movement.
 Completely blocked cockpit visibility.
 Loss of or degraded communications and navigation equipment.
 Icing will exacerbate any emergency situation.
SAMPLE/PRELIMINARY.
VI.
DEICING TRAINING
May 2007
Page 6
METHODS OF DEICING
Manual methods of deicing provide a capability, in clear weather, to clean
an aircraft adequately to allow a safe takeoff and flight. In inclement, cold
weather conditions, however, the only alternative is sometimes limited to placing
the aircraft in a protected area such as a hangar to perform the cleaning process.
Most airports have one or more FBOs who have the equipment, capability, and
experience to clean the aircraft and provide brief protection to allow a safe
takeoff to be performed. If snow, frost, or ice was found adhering to the
aircraft, it must be removed prior to takeoff.
This may be accomplished by any
of the following methods:
WARM HANGERS
Placing the aircraft in a heated hanger to either avoid exposure or to warm
until the snow or ice melts.
This method requires that all moisture that could
freeze is either removed or the aircraft is also treated with FPD fluid to
preclude freezing upon moving of the aircraft into below freezing ambient
conditions. In most cases, severe icing can be anticipated and arrangements
made to have the aircraft hangared.
MECHANICAL METHODS
Various devices such as brooms, brushes, ropes, squeegees, fire hoses, or other
devices have been used to remove dry snow accumulations, the bulk of large wet
snow deposits, or to polish frost to a smooth surface.
HEATED WATER
Use of heated water alone for deicing is generally limited to temperatures above
27˚F (-3˚C) and where the water is heated to about 140˚F followed by a very
close inspection to assure that refreezing does not occur.
DEICE/ANTI-ICE FLUID
There is a one step procedure and a two step procedure:
THE ONE STEP PROCEDURE
The one step method is accomplished using a heated or in some cases an
unheated deice fluid.
In this process residual fluid film provides a
very limited anti-icing protection.
THE TWO STEP PROCEDURE
The two step method involves both deicing and anti-icing.
Deicing is
accomplished by hot water or a hot mixture of deice fluid and water. The
second step of the procedure involves the application of type II/IV fluid to
the critical surfaces of the aircraft.
If heated water alone was used in
the deice process, the second step must be performed before freezing occurs,
generally within three minutes.
VII.
TYPES AND CHARACTERISTICS OF DEICE FLUIDS
There is one deicing fluid and three types of deice/anti-ice fluids.
(1) SAE Type I fluid.
This fluid in the concentrated form contains a minimum of 80% glycols.
Type I HOTs are heavily dependent on the heating of aircraft surfaces. Unlike
Types II, III and IV fluids which contain thickeners to keep fluids on surfaces,
Type I fluids are not thickened and flow off relatively soon after application;
therefore, the heating of aircraft surfaces during Type I fluid deicing and antiicing process contributes to the HOT by elevating the surface temperature above
the freezing point of the residual fluid.
These fluids are used primarily for deicing but provide some limited
anti-icing protection.
SAMPLE/PRELIMINARY.
DEICING TRAINING
May 2007
Page 7
The fluid may be applied hot or cold, but is much more effective in deicing when
applied hot. This ethylene glycol based fluid is generally mixed with water then
heated before application.
The mixture ratio should be determined before application to assure it is the
proper ratio given the current ambient conditions.
The water to fluid mixture
should be at a ratio which lowers the freeze point of the fluid to temperature of
at least 10˚C below the outside air temperature or the aircraft skin temperature.
This temperature difference is referred to as the temperature buffer.
CAUTION: Do not apply undiluted type I fluid in non-precipitation conditions.
The freezing point of pure ethylene glycol is much higher than that diluted with
water. Slight temperature decreases can be induced by factors such as cold
soaked fuel in the wing tanks, reduction of solar radiation by the clouds
obscuring the sun, ambient temperature cooling and wind effects.
(2) SAE Type III fluids
Type III fluid is designed primarily for aircraft with low rotation/
takeoff speeds, although it works equally well on aircraft with higher
rotation/takeoff speeds and offers substantial improvements in anti-icing
performance when compared to Type I fluid.
Type III fluid exhibits times typically less than those of Type II/IV
fluids but significantly longer than those of Type I.
Anti-icing applications of Type III fluids may be heated or unheated.
Type III fluid may be applied diluted or undiluted.
(3) SAE Type II, III and IV fluid.
These fluids contain a minimum of 50% glycols and are considered thickened.
Because of the added thickening agents the fluid can be applied in a thicker film
and remains on the aircraft surfaces until the time of takeoff.
These fluids are used for deicing and anti-icing and provide greater
protection than do type I fluids against ice, frost, or snow formations in
conditions conducive to icing on the ground.
Type II/IV fluid is designed to remain on the aircraft during Ground
operation, thereby providing some anti-icing protection, but to readily flow off
the wings during takeoff.
When these fluids are subjected to shear stress such
as that experienced during takeoff, the viscosity of the fluid decreases
drastically, allowing the fluid to flow off the wings and cause little adverse
effect on the aircraft aerodynamic performance.
NOTE: TYPE II/IV FLUIDS ARE DESIGNATED FOR USE ON AIRCRAFT WITH A
ROTATION SPEED OF 100 KNOTS OR GREATER.
NOTE: TYPE II/IV FLUIDS SHOULD NOT BE USED ON ANY AIRCRAFT UNLESS THE
MANUFACTURER HAS APPROVED THE USE.
Type II/IV fluid is usually applied cold and for that reason is not as
effective as heated Type I fluid as a deicer. Type II/IV fluid can be heated
before application; however, when it is heated it loses much of its
thickness
and therefore is not as effective in anti-icing.
Type IV fluids are more environmentally friendly and have greater holdover
times than do Type II fluids.
SAMPLE/PRELIMINARY.
DEICING TRAINING
May 2007
Page 8
RESTRICTIONS TO TYPE II/IV FLUIDS
NOTE:
Under no circumstances should Type II/IV fluid in the concentrated form
be applied to the following areas of the aircraft:
- Pitot heads and angle of attack sensors
- Control surface cavities
- Cockpit windows and nose of the fuselage
- Lower side of the radome underneath the nose
- Static ports
- Air inlets
- Engines
Some of these areas can be deiced and anti-iced using a diluted Type I fluid,
however, care should always be exercised to assure that neither FPD fluid nor
water enter pitot or static ports.
VIII.
SAFETY PRECAUTIONS WHEN USING DEICE FLUIDS
CAUTION - FLUID DRY-OUT
There have been reported incidents of restricted movement of flight control
surfaces while in flight attributed to fluid dry-out. Diluted Type II and IV fluids
can produce more gel than neat (undiluted) fluids. This is due to the practice in
some geographic locations of using diluted, heated Type II and IV fluids for deicing
and anti-icing. Changing from Type IV to Type II will not necessarily result in an
improvement.
Such events may occur with repeated use of Type II and Type IV fluids without
prior application of hot water or Type I fluid mixtures. This can result in fluid
collecting in aerodynamically quiet areas or crevices, which do not flow off the wing
during the takeoff ground roll. This may lead to an accumulation of fluids in these
aerodynamically quiet areas that can dry to a gel-like or powdery substance. Such
residues have been known to rehydrate and expand under certain atmospheric conditions,
such as high humidity or rain, and then subsequently freeze, typically during flight
at higher altitudes. Rehydrated fluid gels have been found in and around gaps between
stabilizers, elevator tabs and hinge areas. This can be especially critical for
nonpowered control surfaces such as trim tabs. Some pilots reportedly have reduced
altitude until the frozen fluid melts, thus restoring flight control movement.
Such
occurrences have not been reported when a two step deicing/anti-icing procedure is
used in which the first step is a hot Type I fluid mixture or hot water.
It has been suggested that high pressure washing with a hot Type I fluid
water
mix in areas where fluids could accumulate may alleviate the problem.
Aircraft
which are deiced with hot water or a Type I fluid/water mixture and
anti-iced with
a Type II or Type IV fluid have not reported fluid dry-out.
Crews must check aircraft surfaces, quiet areas and crevices for abnormal
fluid thickening, appearances or failure, prior to flight dispatch, ESPECIALLY if Type
II or IV fluid is used exclusively. If you suspect residual as a result of fluid dryout, spray with water from a spray bottle and wait 10 minutes. Residue will rehydrate
in a few minutes and be easier to identify. The residue may require removal before
takeoff.
FLUID APPLICATION
Surveillance of deicing/anti-icing operations conducted in
prior years revealed numerous problems in the actual fluid application process.
These findings included:
a. Instances when the application of fluid was applied in the reverse order of
company approved procedures, ex: approved procedure being from wing tip to
wing root.
b. Insufficient fluid temperature buffer. Type I fluids ONLY.
Deice and Anti-ice fluids are actually FPD fluids - Freezing Point. The FPD
fluids are designed to ensure the residual fluid film remaining on the
aircraft has a freeze point of 10øC/18øF below the OAT for Type I fluid. The
difference between the freezing point of the fluid (10˚C/18˚F) and the OAT is
the temperature buffer.
SAMPLE/PRELIMINARY.
DEICING TRAINING
May 2007
Page 9
c. Incomplete removal of contamination.
Frozen Contaminate on Wing Surfaces at Altitude have been reported. To
minimize such occurrences, during the Deicing Step apply the hot fluid with
the nozzle as close top the surface as possible. Increasing the distance from
the nozzle to the aircraft surface results in progressively greater loss of
fluid heat and deicing capability. Additionally, cover the entire aircraft
surface by the deicing operation rather than relying on fluid flow-back over
contaminated areas. This will provide greater assurance that no frozen
precipitation remains under the deicing fluid. As a final precautionary step,
apply sufficient fluid to ensure that any remaining diluted fluid on the
deiced surfaces is displaced by a fluid with a freezing point of at least
10ºC/18ºbelow the OAT for a Type I fluid.
The effectiveness of any Type II, III or IV fluid is highly dependent on the
training and skill of the individual applying the fluid. When these fluids are used,
they should be even applied so that all critical surfaces, especially the leading edge
of the wings are covered with fluid. In addition, an insufficient amount of antiicing fluid especially in the second step of a two step procedure may cause reduced
holdover times due to the uneven application of the second step fluid.
In conditions where frozen contaminants, such as dry snow, are not adhering to any
part of the wings or other critical surfaces, removing these contaminates with deicing
fluid is inadvisable. A limited amount of dry snow, providing it can be established
that none of the snow is adhering to critical surfaces, may be allowed to “blow off”
during takeoff. However, when the amount of dry snow is significant, it is advisable
to remove it before takeoff with some mechanical means that does not contribute to
melting.
CAUTION - BLEED AIR
Bleed air should always be turned OFF prior to any deicing/anti-icing application.
IX.
HOLDOVER TIME - DEFINITION
The holdover time is the estimated time the application of deicing or anti-icing
fluid will prevent the formation and/or accumulation of ice conditions (frost, snow,
freezing drizzle, freezing fog, etc) on the treated surfaces of the aircraft.
Holdover time begins when the final application of deice/anti-ice fluid
commences and expires when the deice/anti-ice fluid loses its effectiveness.
Holdover time (HOT) guidelines are intended to provide an indication of the
approximate length of time that a freezing point (FPD) fluid will protect aircraft
surfaces during icing conditions while on the ground. It does not imply icing
protection while airborne.
In order to use the HOT tables, the PIC must know: The mixture ratio of the
deice fluid; The type of fluid to be used; The manufacturer, if applicable; The
outside air temperature; The time the application began.
SAMPLE/PRELIMINARY.
X.
DEICING TRAINING
May 2007
Page 10
COMMUNICATION, COMMUNICATION, COMMUNICATION
All responsibility for communication to ensure that a "clean aircraft" free of frozen
contamination adhering to any critical surface of the aircraft prior to flight lies
with the Pilot in Command.
He must communicate clearly and concisely with ground
personnel to determine:
1. The Type fluid used - Type II, III or IV, and the name of the manufacturer,
if a specific fluid.
2. The percentages within the fluid/water mixture for Types II, III & IV.
3. The local time when the final deicing/anti-icing began.
4. The results of the post-deicing/anti-icing check.
5. The pilot should try to coordinate communication with ATC to ensure a valid
time off/departure if contamination conditions still persist.
XI.
HOLDOVER FLUIDS - LIMITATIONS AND LOSS OF EFFECTIVENESS
LIMITATIONS OF FPD DEICE/ANTI-ICE FLUIDS
Deicing/anti-icing fluids do not provide any protection from contamination once
the aircraft is airborne.
Keep in mind that these charts are only to be used as guidelines and should only be
used in conjunction with the pre-takeoff contamination check. The length of the
holdover time can be affected by many factors such as...
 Aircraft component angle, contour and surface roughness
 Ambient temperature
 Aircraft skin temperature
 Fluid application procedure
 Fluid strength
 Fluid film thickness
 Fluid temperature
 Fluid type
 Operation close to other aircraft
 Operation on snow, slush, or wet ramps, taxiways and runways
 Precipitation type and rate
 Radial cooling
 Residual moisture on the aircraft
 Relative humidity
 Solar radiation
 Wind velocity
FUILD FAILURE/LOSS OF EFFECTIVENESS
The pilot should be aware of signs that indicate that the anti-ice/deice
fluid is losing its effectiveness. Those signs may include...
- Progressive surface freezing or snow accumulation
- Random snow accumulation
- Dulling of the surface reflectively (loss of gloss) caused by
gradual deterioration of the deice/anti-ice fluid to slush
Pilots should check a representative surface of the aircraft, defined as
a portion of the wing leading edge, visible by the pilot from within the
aircraft, for fluid failure.
REPRESENTATIVE SURFACES/WHERE FLUID TEND TO FAIL FIRST
Preliminary aircraft testing indicates that the first fluid failures on
test aircraft appear to occur on the leading or training edges of the wing's
surface rather than the mid-chord section of the wing.
Tests also indicate
that fluid failures may be difficult to identify.
SAMPLE/PRELIMINARY.
XII.
DEICING TRAINING
May 2007
Page 11
REMOVAL OF CONTAMINATION FROM AIRCRAFT - DEICING WITH/WITHOUT FLUID
DEICING WITHOUT FLUIDS
Ice, snow, frost and slush should be removed before takeoff. Any frozen
contamination may be removed by placing the aircraft in a heated hangar or
by other normal deicing procedures.
Frost, including underwing frost in the vicinity of the integral fuel
tanks should be removed before takeoff. Underwing frost may be allowed on
some aircraft if the aircraft manufacturer and the FAA certification office
accept such conditions.
Dry, powdery snow can be removed by sweeping with an appropriate brush
or broom or by blowing COLD air or nitrogen gas or other inert gasses across
the aircraft surface. Heavy, wet snow can be removed by mechanical means
such as squeegees and brooms, by using heated water, solutions of heated
water and deicing/anti-icing fluids, or a combination of these techniques.
Any frozen contamination may be removed by placing the aircraft in a
heated hangar or by other normal deicing procedures.
DEICING AND ANTI-ICING AIRCRAFT WITH FLUIDS
An aircraft must be systematically deiced and anti-iced in weather
conditions conducive to icing.
the specific deicing method and procedure
used depends upon the aircraft type,
available equipment,
and the
deicing/anti-icing fluids available.
Some fluids are not permitted to be
used on smaller aircraft.
Each aircraft surface required a specific
technique to achieve a clean aircraft.
XIII.
COMPANY POLICY
Before deicing begins, the PIC must obtain the following information from the
contractor:
a. The fluid type - and if generic or Manufacturer;
b. The fluid/water mix ratio;
c. The pilot shall also request that the contractor report the time of the
beginning of the final application in order to start the holdover time.
At the completion of the deice procedure, the pilot must make a visual inspection of
the aircraft to assure that all ice, snow, and frost has been removed from the
aircraft.
After completion of the deice/anti-ice procedure, the pilot must constantly monitor
the weather conditions for change.
If a Holdover Time is required, the pilot will operate within the time buffer.
OPERATIONS DURING LIGHT FREEZING RAIN/FREEZING DRIZZLE
When operating in actual conditions of light freezing rain or freezing
drizzle, you MUST USE Type II, III or Type IV anti-icing fluid.
If actual conditions have ceased, you must still perform a pre-takeoff
contamination check prior to takeoff.
XIV.
TYPE FLUID APPROVED BY THE FAA AND THE MANUFACTURER FOR EACH AIRCRAFT
1.
---Sample-----
(Deicing Only)
(Deicing Only)
2.
---Sample------
(Anti-Icing)
Type I
in a 50/50 mixture with water
for light icing removal
Type II in a 20% water/80% glycol
for heavy icing removal
Type I, II, and IV