OPERATIONS MANUAL PART A

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1 PAGE: 1 Table of Content A.GENERAL /CHAPTER Cold Weather Operations /General Outdoor Activity and Exposed Skin Protection in Freezing Temperatures Definitions Types of Icing Methods for Removing Ice from the Aircraft Types of De-Icing Fluids Effects on Aircraft Performance Initial Preflight Exterior Safety Inspection Blowing Snow Preflight Exterior Safety Inspection Pilot-in-Command Responsibilities Precautions During Usage during the Application of De-Icing and Anti-Icing Fluids Temperature limits Application Limits Health Precautions Anti-Icing and De-Icing Procedures Taxi-through De-icing Ramp and Taxi Precautions Technical Log After Anti-Icing /De-Icing Inspections Hold-Over Times Taxiing /Before Take-Off /Take-Off Ice and Other Contaminants /Flight Procedures After Take-off and Climb in Cold Weather Use of Anti-icing... 20

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3 PAGE: 3 A. GENERAL / CHAPTER CONTROL OF GROUND DE-ICING AND ANTI- 16. Instructions for the Conduct and Control of Ground De-icing and Anti-Icing Operations 16.1 Cold Weather Operations / General The slightest build-up of ice, frost or snow will result in as much as a 30% loss or lift (with corresponding increase in stalling speed) and up to 40% increase in drag causing degradation in performance which could be critical, especially in the engine failure on take-off situation. Also, controllability will be affected because at the variation in lift degradation on each wing, resulting in altered rolls characteristics. Undetected contamination on the wing can result in forward movement of the contra of lift and cause a rapid pitch-up during rotation. This is further aggravated by the need to select a higher than normal attitude to achieve the lift required for take-off and could result in a stall. A contaminated wing will stall at a lower-than-normal angle, which may not be sufficient to activate the stall warning system. It is imperative, therefore, that any deposits adhering to a parked aircraft are completely removed by de-icing and, if conditions exist for the formation of ice before take-off, the aircraft horizontal surfaces and controls are coated with an ice-preventive agent (anti-icing) which will retain its effectiveness for the period between application and take-off (holdover time). Note: The guidelines given in this section are general and do not specify the De-Icing and Anti - Icing specific procedures for the aircraft. Refer to the approved AFM for additional information Outdoor Activity and Exposed Skin Protection in Freezing Temperatures Protective clothing such as hats, gloves and other appropriate clothing should be worn when working in freezing temperatures. Any pre, post flight activity or runway inspection during freezing temperatures requires that the Flight Crew take precautions. Flight Crew and ground crew should take care when touching any metal part of the aeroplane, tools or torches without using gloves. Unprotected skin can stick to metal. Flight and ground crews should seek shelter out of the elements to discuss a problem that has been found during the pre, post-flight inspection or ground operations that require personnel to be outside in freezing temperatures Definitions Active Frost Active frost is a condition when frost is forming. Active frost occurs when aircraft surface temperature is:

4 PAGE: 4 At or below 0 C (32 F) and At or below dew point Anti-Icing Anti-Icing is a precautionary procedure that provides protection against the formation of frost or ice and accumulations of snow or slush on treated surfaces of the aircraft for a limited period of time (holdover time). Cold-soak Effect Cold-soak Effect is when the wings of an aircraft are said to be "cold-soaked" when they contain very cold fuel as a result of having just landed after a flight at high altitude or from having been re-fuelled with very cold fuel. Whenever precipitation falls on a cold-soaked aircraft when on the ground, clear icing may occur. Even in ambient temperatures between -2 C and +15 C, ice or frost can form in the presence of visible moisture or high humidity if the aircraft structure remains at 0 C or below. The following factors contribute to cold-soaking: Temperature and quantity of fuel in fuel cells; Type and location of fuel cells; Length of time at high altitude flights; Temperature of re-fuelled fuel; and Time since re-fueling. Contamination Contamination is understood as all forms of frozen or semi-frozen moisture, such as snow, slush or ice. Contamination Check A Contamination Check is a check of aircraft surfaces for contamination, to determine the need for de/antiicing. De-Icing Procedure A De-Icing procedure is a procedure which frost, ice, snow or slush is removed from an aircraft in order to provide uncontaminated surfaces. De-Icing/Anti-Icing De-Icing/Anti-Icing is the combination of the procedures described under "Anti-Icing" and 'De-Icing' above may be performed in one or two steps, depending on prevailing conditions.

5 PAGE: 5 Freezing Conditions Freezing Conditions are conditions in which the outside air temperature is below +3 C (37.4 F) and visible moisture in any form (such as fog with visibility below 1.5 km, rain, snow, sleet or Ice crystals) or standing water, slush, ice or snow is present on the runway. Freezing Drizzle Freezing Drizzle is fairly uniform precipitation composed exclusively of tine drops (diameter less than 0.5 mm [0.02 in]) very close together which freezes upon Impact with the ground or other exposed objects. Freezing Fog Freezing Fog is a suspension of numerous very small water droplets which freezes upon impact with ground or other exposed objects, generally reducing the horizontal visibility at the earth's surface to less than 1 km (5/8 mile). Freezing Precipitation Freezing precipitation corresponds to freezing rain or freezing drizzle. Freezing Rain Freezing rain occurs when precipitation from warmer air aloft falls through a temperature inversion into below freezing air underneath. The larger droplets may impact and freeze behind the area protected by surface deicers. Freezing rain and drizzle can cover large surface areas in a very short time and distort the shape of the airfoil shape, making flight extremely dangerous or impossible in a matter of a few minutes. Freezing drizzle is commonly formed when droplets collide and coalesce with other droplets. As the droplets grow in size, they begin to fall as drizzle. Both freezing rain and drizzle can fall below a cloud deck to the ground and cause ice to form on aeroplane surfaces during ground operations, take-off, and landing if the surface temperature is below freezing. Along a cold front, the cold air flows under the warm air, lifting the warm air rapidly resulting in the formation of cumulus or cumulonimbus clouds. Along a warm front, the warmer air tends to slide over the colder air, forming stratus clouds conducive to icing. As you approach the front, the clouds build quickly and the clear air between layers rapidly disappears. Frost / Hoar Frost/hoar is frost and or ice crystals that form from ice saturated air at temperatures below 0oC (32 F) by direct sublimation on the ground or other exposed objects. Hail Precipitation Hail precipitations are small balls or places of ice with a diameter ranging from 5 to >50 mm (0.2 to >2.0 in.) falling either separately or agglomerated.

6 PAGE: 6 Holdover Time Holdover Time is an ESTIMATED time for which an anti-icing fluid will prevent the formation of frost or Ice and tile accumulation of snow on the protected surfaces of an aircraft under weather conditions. The protection time is dependent upon weather conditions and fluid mixture selected and cannot be precisely predetermined for each application. Icing Conditions Icing Conditions exist at OAT 10 C or below and visible moisture in any form is encountered (such as fog with visibility of 1500 meters (one mile) or less, rain, and snow, sleet and ice crystals). Ice Pellets Ice pellets are precipitation of transparent (grains of ice), or translucent (small hall) pellets of ice, which are spherical or irregular and which have a diameter of 5 mm (0.2 in.) or less. The pellets of ice usually bounce when hitting hard ground. Light Freezing Rain Light Freezing Rain is precipitation of liquid water particles which freezes upon impact with exposed objects, either in the form of drops of more than 0.5 mm (0.02 in) or smaller drops which In contrast to drizzle, are widely separated. Measured intensity of liquid water particles are up to 2.5 mm (0.10 In) / hour or 25 grams/dm2/hour with a maximum of 0.25 mm (0.01 in) in 6 minutes. Lowest Operational Use Temperature (LOUT) Lowest Operational Use Temperature (LOUT) is the lowest temperature at which a fluid has been tested and certified as acceptable in accordance with the appropriate aerodynamic acceptance test while still maintaining the 7 C - freezing paint temperature buffer. Moderate and Heavy Freezing Rain Moderate and Heavy Freezing Rain is precipitation of liquid water particles which freezes upon impact with the ground or other exposed objects, either in the form of drops of more than 0.5 mm (0.02 inch) or smaller drops which, in contrast to drizzle, are widely separated. Measured intensity of liquid water particles is more than 2.5 mm/hour (0.10 Inch/hour) or 25 grams/dm2/hour. Pre-Take off Check Pre-Take off Check is a check to assess whether the applied holdover time is still appropriate. This check is normally performed from inside the flight-deck.

7 PAGE: 7 Pre-Take off Contamination Check Pre-Take off Contamination Check is a check of the critical surfaces for contamination. This check will be performed when the condition of the critical surfaces of the aircraft cannot be effectively assessed by a pretakeoff check or when the applied holdover time has been exceeded or if there is any doubt regarding the effectiveness of anti-icing. This check is normally accomplished from outside the aircraft just before commencing inks off roll. Rain On Cold Soaked Wing Rain On Cold Soaked Wing is water forming ice on the wing surface when the temperature of the aircrafts wing surface is at or below 0 C (32 F). Rain and Snow (Sleet Rain and Snow (Sleet) is precipitation in the form of mixture of rain and snow. Note: For operation in light rain and snow (sleet) treat as light freezing rain. Slush Snow or Ice Is precipitation in the form of Slush Snow or Ice that has been reduced to a soft watery mix by rain, warm temperatures, and/or chemical treatment. Snow Precipitation Snow precipitation of ice crystals, most of which are branched, star-shaped or mixed with un-branched crystals. At temperatures higher than -5 'C (23 F), the crystals are generally agglomerated into snowflakes. Snow Grains Precipitation Snow grains precipitation is very small white and opaque particles of ice that is fairly flat or elongated with a diameter of less than 1 mm (0.04. in.). When snow grains hit hard ground, they do not bounce or shatter. Note: For holdover time purposes treat snow grains as snow. Snow Pellets Precipitation Snow pellets precipitation is a white, opaque particles of ice. The particles are round or sometimes conical; their diameter range from about 2-5 mm ( in.). Snow pellets are brittle, easily crushed; they do bounce and may break a hard ground Types of Icing Blowing Snow An aircraft can be exposed to blowing snow when parked outside. Snow can enter openings, freeze, and obstruct normal operations.

8 PAGE: 8 Dry Snow Dry Snow is a fine powder like snow which does not stick and may be blown or brushed away. Clear Ice Clear Ice is a coating of ice, generally clear and smooth, but with some air pockets. it is formed on exposed objects at temperatures at, below or slightly above the freezing temperature by freezing of super-cooled drizzle, droplets or raindrops. Since only a little air is trapped the result is a clear or glazed appearance. Crews must be aware of the difficulty of detecting clear Ice and, in some situations; its presence may only be detected by touch. it can also form on aircraft surfaces below a layer of snow and time ice. Significant deposits can form on upper wing surfaces in the vicinity of fuel tanks after refueling with lowtemperature fuel or when sufficient super-cooled fuel remains in tanks after a long flight at altitude. This has occurred at ambient temperatures as high as 14 C. Conversely, refueling with relatively warm fuel can cause dry falling snow to melt with the danger of rehearing on the upper surface of the wing. Freezing Rain Freezing rain occurs when precipitation from warmer air aloft falls through a temperature inversion into belowfreezing air underneath. The larger droplets may impact and freeze behind the area protected by surface deicers. Freezing rain and drizzle can cover large surface areas in a very short time and distort the shape of the airfoil shape, making flight extremely dangerous or impossible in a matter of a few minutes. Freezing drizzle is commonly formed when droplets collide and coalesce with other droplets. As the droplets grow in size, they begin to fall as drizzle. Both freezing rain and drizzle can fall below a cloud deck to the ground and cause ice to form on aeroplane surfaces during ground operations, take-off, and landing if the surface temperature is below freezing. Along a cold front, the cold air flows under the warm air, lifting the warm air rapidly resulting in the formation of cumulus or cumulonimbus clouds. Along a warm front, the warmer air tends to slide over the colder air, forming stratus clouds conducive to icing. As you approach the front, the clouds build quickly and the clear air between layers rapidly disappears. Frost Ice Crystals Frost Ice Crystals are deposits formed on cold, clear nights by sublimation on surfaces which have a temperature lower than the surrounding air. Such deposits on leading edges and upper surfaces, even when they are very thin (hoar frost) can seriously affect an aircraft's performance. Frost 3mm or less on the lower surface of a wing has no effect and may be discounted. The approved AFM specifies limits of frost deposits for take-off.

9 PAGE: 9 Rime Ice Rime Ice is an opaque white or milky deposit formed by the rapid freezing of super cooled water droplets, trapping air between them, as they impinge upon an exposed aircraft. In fog, mist or drizzle conditions with temperature at or below freezing point rime ice can form on any part of the aircraft and may become very thick on the windward side. Wet Snow Wet Snow has a much higher liquid content and tends to stick on airframe/engine components and may freeze Methods for Removing Ice from the Aircraft Anti-Icing Anti-icing is a precautionary measure to prevent ice deposits from forming or accumulating on the surfaces of a clean aircraft. It is regarded as step two after de-icing and consists of spraying specific fluids on the aircraft. De-icing De-icing is the removal of any deposit of snow, slush or ice from the wing, stabilizer and control surfaces. This is usually regarded as one-step procedure and can be a combination of facility, handheld equipment and fluids. Hangars Warm hangars provide a place for warming the aircraft and melting ice, frost, and snow formations prior to departure. Mechanical Methods Mechanical methods are considered to be various devices such as brooms, brushes, or other devices can be used to remove dry snow accumulations, to remove the bulk of large wet snow deposit, or to polish frost to a smooth surface. These manual methods require that caution be exercised to preclude damage to aircraft skins and other critical components. Anti-Icing and De-icing Fluids Type I fluid mixed with heated water. Type II, Type III or Type IV fluid mixed with water. The above are normally applied heated to assure maximum efficiency and are used for quickly removing frost and to prevent or retard ice formation during overnight storage. In addition, they are used to assist in melting

10 PAGE: 10 and removal of snow or other ice formations such as develop as a result of freezing rain or drizzle, and for assisting in the removal of ice or frost formations accumulated during a previous flight Types of De-Icing Fluids Type I Fluid Type I Fluid is a heated water/glycol solution that is used for deicing of the aircraft. Type I fluid offers limited protection against re-freezing or ice or snow buildup during precipitation or frost-forming conditions. Type II Fluid Type II Fluid provides anti-icing protection and is applied after aircraft has been de-iced. Type II fluid can be applied neat (100% glycol) or mixed with water to a minimum concentration of 50/50. The fluid s relatively high viscosity (thickening agent) is effective in improving the anti-icing holdover time. During takeoff, the slipstream imparts a shear stress to the fluid layer causing it to flow off the surface to which it was applied. Type III Type III fluids are designed for aircraft that have a shorter time to rotation and this should make it acceptable for some aircraft that have a Vr of less than 100 knots unless otherwise specified by the aircraft manufacturer. Type IV Fluid Type IV Fluid provides superior anti-icing protection and is applied after the aircraft has been de-iced. This fluid is normally applied neat (100%), and cold. Type IV fluid uses thickening agents to increase the viscosity of the fluid and consequently Type IV fluid provides significant longer holdover time. During takeoff, the slipstream imparts a shear stress to the fluid layer causing it to flow off the surface to which it was applied Effects on Aircraft Performance The application of any de-icing or anti-icing fluids that adhere to the surface of the aircraft will cause an minimum effect on performance. The Pilot-in-Command shall consult the approved AFM and be familiar with the take-off, climb and flight characteristics of the aircraft before taxiing for take-off after de-icing or anti-icing fluids have been applied to the aircraft Initial Preflight Exterior Safety Inspection A thorough pre-flight inspection is more important in extreme temperatures because those temperature extremes may affect the aircraft or its performance. At extremely low temperature, the urge to hurry the preflight of the aircraft is natural, particularly when the aircraft is outside and adverse weather conditions exists, which make the pre-flight physically uncomfortable for the pilots.

11 PAGE: 11 This is the very time to perform the most thorough pre-flight inspection. Areas that require special attention during a pre-flight during cold weather operations depend on the aircraft design and are identified in the approved AFM. pre-flight should include the following items: Wing and Wing leading edges, upper and lower surfaces. Conduct a hands-on inspection to verify that all surface are clean. Vertical and horizontal stabilizing devices, leading edges, upper surfaces, lower surfaces, and side nacelles; Lift/drag devices such as trailing edge flaps. Flaps, Spoilers and speed brakes. All flight control surfaces and control balance bays. Engine nacelle/pylon Fan blades, PT2 probe Windshields and other windows necessary for visibility. Antennas Fuselage Exposed instrumentation devices such as angle of attack vanes, pitot-static pressure probes, and static ports. Fuel tank and fuel cap vents. Cooling and auxiliary power unit (APU) air intakes and exhaust Blowing Snow Preflight Exterior Safety Inspection If an aircraft is exposed to blowing snow, additional inspections and special attention should be given to openings in the aircraft where snow can enter, freeze, and obstruct normal operations. The following openings should be free of snow and ice before flight: Pitot tubes and static system sensing ports; Landing gear and landing gear doors; Heater intakes; Landing gear and landing gear doors Engine nacelle/pylon; Fan blades; All flight control surfaces;

12 PAGE: 12 Fuel vents Pilot-in-Command Responsibilities The Pilot-in-Command is responsible to ensure that de/anti-icing performed conforms to the present requirements and those which are specific to the aircraft type (Refer to the approved AFM). Therefore, the Pilot-in-Command's instructions concerning the treatment and the fluid mixtures to be used take precedence over local de/anti-icing procedures. The Anti-Icing code, as well as the concentration of the applied fluid/water mixture and the time of the beginning of the final de-icing/anti-icing step, is then transmitted to the Flight Crew. However, they shall not be transmitted before the post de-icing/anti-icing check is completed. After satisfactory de- /anti-icing it is for the Pilot-in-Command to decide whether the holdover time is adequate for taxiing and takeoff. The AEA code defines the treatment (de- icing or anti-icing) applied to the aircraft. It includes the AEA fluid classification, concentration, time of starting the treatment and date. Protection period is measured from the time of treatment start. Notes: All fluids which are not approved as AEA type 2 shall be classed as AEA Type 1 for protection time and the code used. The mix ratio is by volume with the de-icing fluid quoted first. A 25/75 mix contains 25% de-icing fluid and 75% water. When the mix used differs from those tabulated, use the next lower concentration code. Example: An 80/20 mix shall be coded 75/25. The Flight Crew is responsible to perform the normal walk around pre-flight inspection in order to note any aircraft surface contamination and direct any required de-icing/anti-icing operations. The ground handling agent releasing the aircraft after de/anti-icing is responsible for the performance and the verification of the results of the treatment and to report it to the Pilot-in-Command. The Pilot-in-Command has the ultimate responsibility to determine if the aircraft is clean and that the aircraft is in a condition for safe flight Precautions During Usage during the Application of De-Icing and Anti-Icing Fluids The application process should be continuous and as short as possible. Anti-icing should be carried out as near to the departure time as operationally possible in order to utilize maximum holdover time. The ant icing fluid shall be distributed uniformly over all surfaces to which it is applied. In order to control the uniformity, all horizontal aircraft surfaces shall be visually checked during application of the fluid. The correct amount is indicated by fluid just beginning to drop off the leading and trailing edges.

13 PAGE: 13 The most effective results are obtained by commencing on the highest part of the wing section and covering from there towards the leading and trailing edges. On vertical surfaces, start at the top and work down: Wing upper surface and leading edges must be treated with fluid. Horizontal stabilizer upper surfaces including leading edges and elevator upper surfaces. Vertical stabilizer and rudder must be treated with fluid. De-icing the top of the fuselage is especially important on aircraft with aft- mounted centerline and aft-side fuselage mounted engines. The ingestion of ice or snow into a turbine engine may result in compressor stalls or damage to the engine. During anti-icing and de-icing, the moveable surfaces shall be in a position as specified by the aircraft manufacturer. Engines are normally shut down but may remain running at idle during de-icing/anti-icing operations. Air conditioning and/or APU air shall be selected OFF, or as recommended by the airframe and engine manufacturer. De-icing/anti-icing fluids shall not be sprayed directly onto brakes, wheels, exhausts or thrust reversers. De-icing/anti-icing fluid shall not be directed into the orifices of pitot heads, static ports or directly onto airstream direction detectors probes/angle of attack airflow sensors. All reasonable precautions shall be taken to minimize fluid entry into engines, other intakes/outlets and control surface cavities. Fluids shall not be directed onto flight deck or cabin windows as this can cause crazing of acrylics or penetration of the window seals. Prior to the application of de-icing/anti-icing fluids all doors and windows should be closed to prevent: Galley floor areas being contaminated with slippery de-icing fluids. Upholstery becoming soiled. Also, special precautions are necessary to ensure that residual fluids do not enter sensitive instrumentation or flow over the cockpit windows during taxi or take-off. Caution: Anti-icing fluids may not flow evenly over wing leading edges, horizontal and vertical stabilizers. These surfaces should be checked to ensure that they are properly coated with fluid Temperature limits When performing two-step de-icing/anti-icing, the freezing point of the fluid used for the first step shall not be more than 3 C (5 F) above ambient temperature. (See also tables 1 and 2.) The freezing point of the type I fluid mixture used for either one- step de-icing/anti-icing or as a second step in the two-step operation shall be at least 10 C (18 F) below the ambient temperature. In no case shall this temperature be lower than the lowest operational use temperature (LOUT) Caution: Type I fluids supplied as concentrates for dilution with water prior to use shall not be used undiluted. For exceptions refer to fluid manufacturer s documentation. Type II / Type III / Type IV fluids used as de-icing/anti-icing agents have a lower temperature application limit of -25 C (-13 F). The application limit may be lower, provided a 7 C (12,6 F) buffer is maintained between

14 PAGE: 14 the freezing point of the neat fluid and outside air temperature. In no case shall this temperature be lower than the lowest operational use temperature (LOUT) as defined by the aerodynamic acceptance test Application Limits Under no circumstances shall an aircraft that has been anti-iced receive a further coating of anti-icing fluid directly on top of the contaminated film. If an additional treatment is required before a flight, a complete de-icing/anti-icing shall be performed (see application Tables 1 and 2). Ensure that any residues from previous treatment are flushed off. Anti-icing only is not permitted. Caution: The repeated application of type II, III or IV fluid may cause residues to collect in aerodynamically quiet areas, cavities, and gaps. The Application of hot water or heated type I fluid in the first step of the de-icing/anti-icing process may minimize the formation of residues. Residues may re-hydrate and freeze under a certain temperature, high humidity and/or rain conditions and may block or impede critical flight control systems. These residues may require removal. Note: Consult the aircraft manufacturer requirements and aircraft washing recommendations Health Precautions Ethylene and ethylene glycol are moderately toxic for humans. Exposure to vapors or aerosol of any fluid may cause transitory irritation of the eyes. Swallowing small amounts of ethylene or ethylene glycol may cause abdominal discomfort and pain, dizziness Anti-Icing and De-Icing Procedures Anti-Icing and De-Icing can be performed in one step or in two steps: One-step de-icing/anti-icing is performed with a heated anti-icing fluid to clean the aircraft without subsequent application of anti-ice fluid. The fluid used to de-ice the aircraft remains on aircraft surfaces to provide limited anti-ice capability. The correct fluid concentration shall be chosen with regard to desired holdover time and is dictated by outside air temperature and weather conditions (see tables 1 and 2). Caution: Wing skin temperatures may be lower than OAT. A stronger mix (more glycol) can be used under these conditions. Two-step de-icing/anti-icing is a de-icing of the aircraft (cleaning) immediately followed by the application of anti-ice fluid. The correct fluid shall be chosen with regard to ambient temperature. After de-icing, a separate over-spray of anti-icing fluid shall be applied to protect the relevant surfaces thus providing maximum possible anti-ice capability. The second step is performed with anti-icing fluid. The correct fluid concentration shall be chosen with regard to desired holdover time and is dictated by outside air temperature and weather

15 PAGE: 15 conditions (see tables 1 and 2). The second step shall be performed before first step fluid freezes (typically within 3 min), if necessary area by area. When applying the second step fluid, use a spraying technique which replaces the first step fluid and provides a sufficient amount of second step fluid to completely cover the surfaces with an adequate film thickness. Where re-freezing occurs following the initial treatment, both first and second step must be repeated. Caution: Wing skin temperatures may be lower than OAT. A stronger mix (more glycol) can be used under these conditions. With regard to holdover time provided by the applied fluid, the objective is that it is equal to or greater than the estimated time from start of anti-icing to start of takeoff based on existing weather conditions. Aircraft shall be treated symmetrically, that is, left-hand and right-hand side shall receive the same treatment. Note: Aerodynamic problems could result if this requirement is not met. The one-step procedure is a de-icing procedure. A functional flight control check may be required after de-icing/anti-icing depending upon aircraft type (see the approved AFM). This is particularly important in the case of an aircraft that has been subjected to an extreme ice or snow covering Taxi-through De-icing A pre-briefing must be performed with ground handling. VHF contact must be maintained during the operation and ground handling must confirm the results of the treatment. Caution should be used for the use of the aircraft APU, if equipped and the extension of flaps. Consult the approved AFM for specific instructions. Prior commencing de-icing actions on the de-icing area, the crew is requested to close air bleed system in order to prevent ingestion of de-icing fluid into ducts and air conditioning. After accomplished de-icing and prior departing the de-icing area, the crew is advised as a safety measure to confirm with the de-icing team chief that all de-icing vehicles are clear of the aircraft. Deicing with engines running may be performed in taxi-through facilities at particular aerodromes. The AFM prescribes procedures and checklists for this procedure. Pre-briefing must be conducted between the Flight Crew and the ground agent personnel conducting the de-icing to ensure that the ground personnel is aware of any specific requirements called for by the Flight Crew or dictated by the approved AFM. VHF contact must be maintained with the de-icing supervisor throughout the operation. The de-icing supervisor is responsible for confirming that the aircraft is completely free of ice or snow prior to releasing it. As soon as the aircraft is clear of the facility, the air-conditioning may be switched ON again. Verify that the taxi and take-off checklists are duly completed. When lining up for take-off and prior to releasing the brakes accelerate the engines to verify proper operation.

16 PAGE: Ramp and Taxi Precautions Abnormal engine indications may occur during engine start, with oil pressure exceeding normal limits until oil temperature rises. This is acceptable provided the engine is operated at no more than idle thrust until indications are normal. Be alert to the possibility of engine inlet ice buildup during taxi and ground holding operations. Ice can form in engine inlets at temperatures above 10 C with high humidity present during extensive ground holds with the engines at idle. If visible moisture is present with a temperature below that specified in the approved AFM/AFM, nacelle anti-ice systems must be selected ON after each engine is started. Taxi with great care since rutted areas because steering problems. Neither aircraft nor ground vehicles are capable of stopping quickly. When guide lamp installations are available, make use of them to align the aircraft in the gate area. Snow may cover the normal taxi markings. Be alert to the possibility of foreign object damage due to high snow in ramp areas or along narrow taxiways. Test braking and steering capabilities frequently. Maintain a greater distance than normal from other traffic to avoid jet blast, which could adversely affect antiice treatment and/or blow contaminants onto the aircraft. Engine thrust may need to be higher than normal to overcome the drag caused by slush or snow. Changes should be made slowly and carefully to avoid blowing equipment and/or contaminants into other aircraft. At intervals during prolonged taxi and immediately before take-off, engines must be run up to higher settings as specified in the approved AFM/AFM. Flaps should be kept UP when taxiing through slush or standing water, with pre-take-off checks delayed until they are able to be lowered and anti-skid selected ON. Hold well clear of an active runway as a landing aircraft is more likely to deviate from the centerline if braking conditions are marginal. Slush thrown up by landing aircraft can be ingested by engines, because airframe damage and degrade anti-ice treatment Technical Log Whenever de-icing has taken place the Pilot-in-Command (or the person designated by the Pilot-in-Command) must make an appropriate entry in the technical log showing the times of start and completion of the de-icing process After Anti-Icing / De-Icing Inspections A Flight Crew Member or a qualified Cabin Crew Member will look out forward, side and aft, both right and left side windows to ensure that no snow or frost is still adhering to any visible surfaces prior to the aero plane taxiing for take-off.

17 PAGE: 17 The appointed person will confirm that the visible aero plane surfaces and clear of snow and ice. Clear ice, is difficult to detect from inside the aero plane after a deicing / anti-icing has been performed. Clear ice may still be present below the layer of snow and slush has been removed after deicing / anti-icing. If there is any doubt with regards to clear ice still being present on any surface, the Pilot-in-Command shall designate a Flight Crew Member to visually check to ensure removal of all ice after deicing / anti-icing procedures. Some cases this may require an inspection by touch. If any contaminant is still present, the Pilot-in-Command will return to the de-icing / anti-icing ground service area and advise the ground crew to apply more de-icing / anti-icing fluid to the contaminated areas until they are free of all contaminants. Should it be necessary for an aero plane to be sprayed again prior to flight, the external surfaces shall be deiced first with a hot fluid before a further application of de-ice fluid is made. Under NO circumstances will the aero plane that has just been de-iced, receive another application of cold, undiluted fluid applied directly on top of the existing film Hold-Over Times Holdover time is the estimated time for which an anti-icing fluid will prevent the formation of frost or ice and the accumulation of snow on the protected surfaces of an aircraft. With a one-step de-icing/anti-icing operation the holdover time begins at the start of the operation and with a two-step operation at the start of the final (anti-icing) step. Holdover time will have effectively run out when frozen deposits start to form/accumulate on treated aircraft surfaces. In case the calculated holdover time after anti-icing has expired prior to take- off, complete de / ant icing must be performed, it must be assured that previous treatment is completely washed off or de-iced before a new coating of anti-icing is applied. Caution: Heavy precipitation rates or high moisture content, high wind velocity or jet blast may reduce holdover time below the lowest time stated in the range. Holdover time may also be reduced when aircraft skin temperature is lower than OAT. Therefore, the indicated times should be used only in conjunction with a pre-takeoff check. The holdover time depends on the type of fluid used: Type I (unthicken) has a high ethylene or propylene glycol content and a low viscosity. Due to their properties, Type I fluids form a thin liquid wetting film, which provides limited holdover time, especially in conditions of freezing precipitation. With this type of fluid no additional holdover time would be provided by increasing the concentration of the fluid in the fluid/water mix.

18 PAGE: 18 Type II, III and IV have a minimum glycol content of about 50% in the form of high molecular polymers, with a thickening agent, enabling the fluid to remain on the aircraft surfaces for longer periods at rest or when taxiing, and to flow-off the aerodynamic surfaces as soon as speed increases. With this type of fluid additional holdover time will be provided by increasing the concentration of the fluid in the fluid/water mix, with maximum holdover time available from undiluted fluid. The following tables give an indication as to the time frame of protection that could reasonably be expected under conditions of precipitation. However, due to the many variables that can influence holdover time, these times should not be considered as minimums or maximums and only as a general guidance as the actual time of protection may be extended or reduced, depending upon the particular conditions existing at the time. The lower limit of the published time sign is used to indicate the estimated time of protection during moderate precipitation and the upper limit indicates the estimated time of protection during light precipitation. Note: See the Anti-Icing and De-Icing Guidelines and Holdover Times Guidance Tables 1 through 10 in the following two sections for more information Taxiing / Before Take-Off / Take-Off Before a take-off is attempted, consult the approved AFM limitations cold weather operations section and appropriate aeroplane performance manual to determine any loss of take-off performance for operations in cold weather. Flat spots may form on tires when the aeroplane is parked in cold weather overnight. A longer taxi will allow the tires to warm up and return the tires to a normal round state. If taxi time is short, moderate airframe vibration may be experienced during the take-off roll until or on the take-off roll. This may cause nose wheel vibration on take-off and a great deal of noise in the passenger cabin. Nose gear steering should be exercised in both directions during taxi to circulate hydraulic fluid through steering cylinders and minimize steering lag caused by low temperatures. The Flight Crew will avoid using large control inputs for side-slip correction in strong crosswind conditions when taxiing on slick or icy taxiways. All turns should be made at a reduced taxi speed when taxing in strong crosswinds on icy taxiways or icy runways. Excessive taxi speeds may cause the aero plane to slide or skid. Maintain a greater distance than normal between aero planes when taxiing in standing water, ice or snow. Engine exhaust from an aero plane that is taxiing ahead may melt snow or slush and blow it onto the aero plane behind. This blown snow of ice may freeze again forming ice. Taxi with the wing flaps and leading edge devices in the up position, if taxiing through slush or standing water in low temperatures, taxiing with wing flaps up will protect the wing flap drives from snow and slush accumulation splashing up from the main gear wheels. The ENTIRE before take-off check list will be completed to ensure that the wing flaps and leading edge devices are set correctly for take-off.

19 PAGE: 19 Use minimum thrust while taxiing and to the initial alignment with the runway centerline. Apply thrust smoothly and evenly for a symmetrical spool-up of the engines. Set take-off thrust and correct for deviations away from the runway centerline with immediate steering and or rudder action. During take-off on icy runways, the lag in nose wheel steering and the possibility of nose wheel skidding can be a hazard which must be anticipated and corrected for immediately. Note: It is possible to sustain damage on the lower fuselage and wing area from the slush thrown up from the wheels during the take-off run. The acceleration rate during the low speed portion of the take-off roll is usually normal but may deteriorate during the high-speed portion. Slush and or water can accumulate in the leading edge flaps and then freeze during climb. Conditions permitting, the anti-ice should be placed ON after flap retraction is complete to melt any accumulation of slush. If the decision is made to reject the take-off and the runway is slick, confirm maximum braking, manually deploy the spoilers if below V1 (if considered necessary) and use maximum symmetrical reverse thrust. If a skid develops, reduce reverse thrust to idle reverse. Use rudder pedal steering if possible for directional control. The rudder and differential braking may also be used as necessary for directional control Ice and Other Contaminants / Flight Procedures The Pilot-in-Command shall not commence a flight nor intentionally fly into expected or actual icing conditions unless the aero plane is certificated and equipped to cope with such conditions. Note: The approved AFM procedures for the aero plane shall always be followed if the flight encounters unexpected or actual icing conditions. If the aero plane is not certified for flight into forecast or actual icing conditions, the Pilot-in-Command will advise ATS and request a 180 turn to avoid and exit the icing conditions After Take-off and Climb in Cold Weather When all obstacles have been cleared, retract the flaps and select anti-ice ON to melt any accumulation of slush that might have collected internally in the flaps or slats during the take-off run. Any ice formations that may have develop on the empennage during take-off will be removed when the aero plane accelerates after take-off due to the increasing aero planes speed which will result in a higher skin temperature. When icing conditions are anticipated, place engine anti-ice switches ON before penetrating icing conditions to prevent ice buildup.

20 PAGE: 20 Whenever icing conditions are encountered in-flight, an increase in engine vibration level may develop. The engine will normally shed ice and vibration levels should return to normal. If the sustained high vibration is indicated in icing conditions and operational circumstances permit, quickly retarding 1 thrust lever at a time to idle for 5 seconds then restoring thrust may assist in shedding ice. The recommended use of the anti-ice system is to remove ice after an appreciable amount has formed. A slight performance loss will result when the anti-ice system is ON Use of Anti-icing Wing anti-icing should be used as a deicing/anti-icing system after a specific amount of ice, listed in the approved AFM, has formed. It should not normally be used as an anti-ice system that is continuously switched on in icing conditions, due to performance penalties and runback ice formations. Operation of the anti-ice system with flaps extended is not recommended. Ice accumulation on the Flight Crew compartment windshield frames, windshield Centre post, windshield wiper post, or side windows can be used as an indication that airframe-icing conditions exist.