On the use of Liquid Water Equivalent (LWE) for estimating snowfall intensity and freezing drizzle intensity versus the use of visibility Roy Rasmussen.

On the use of Liquid Water Equivalent (LWE) for estimating snowfall intensity and freezing drizzle intensity versus the use of visibility Roy Rasmussen National Center for Atmospheric Research Presentation to OFCM meeting Feb. 14, 2008

Background Rough ice accumulation on a wing, the thickness of a thumbnail, leads to a loss of lift and increase in drag of 25%, requiring that aircraft be deiced with Type I (deicing), and/or Type II or IV anti-icing fluids (both either ethylene or propylene glycol based) to remove ice and protect against re-icing before takeoff. Holdover time is the period that deicing/anti-icing fluids protect against re-icing.

Background  Outdoor and indoor testing of deicing fluids for endurance time has shown that the liquid equivalent snowfall rate is the main cause for fluid failure: –Dilutes the fluid, leading to runoff –Causes the freeze temperature of the fluid to increase  Holdover times are also sensitive to fluid temperature

Deicing fluid endurance time as a function of liquid equivalent rate Regression analysis that provides a power law relationship is used for each fluid and each dilution for each weather condition

25 g/d2/hr = 17 minutes endurance time at -5 C 12 g/d2/hr = 100 minutes endurance time at 0 C 12 g/d2/hr = 55 min endurance Time at -5 C

2.5 – 4 g/d 2 /hr Very Light 4 – 10 g/d 2 /hr Light 10-25 g/d 2 /hr Moderate > 25 g/d 2 /hr Heavy

Very Light Light Moderate Heavy

Moderate Light

Upper range of snow cell at -5 C Lower range of snow cell at -5 C Type IV

Snowfall Intensity by Visibility NWS Category Light Moderate Heavy Visibility Liquid Equivalent Snowfall Rate > 5/8 mi < 1.0 mm/hr 5/8-5/16 mi 1.0 to 2.5 mm/hr 1/4 mi or less > 2.5 mm/hr - SN SN + SN

Background An analysis of five aircraft ground deicing accidents showed that the snowfall rate as determined by a weighing snowgauge was nearly identical for each accident (near 2.5 mm/hr), but that the snowfall intensity reported to the pilot from the METAR using visibility ranged from light to heavy. “Common Snowfall Conditions Associated with Aircraft Takeoff Accidents”, 2000: R. Rasmussen, J. Cole, R.K. Moore, and M. Kuperman. J. Aircraft, Vol. 37, 110 – 116.

Liquid-equivalent Precipitation Rate (in/hr) Light S- Mod S Heavy S+ Snow Intensity Based on Visibility Alone.004 in/hr.04 in/hr.08 in/hr.10 in/hr.4 in/hr J x * + l Accidents Plotted Against Visibility And Liquid-Equivalent Precipitation Rate

Background Since the current method to estimate snow intensity is based on visibility, I decided to do a follow up study to examine this relationship in more detail. Study based on observations from well shielded weighing snowgauges and calibrated automatic visibility sensors. Visibility sensor calibrated during snow conditions by a manual observer. Theoretical study also performed and compared to the observations. “The Estimation of Snowfall Rate Using Visibility”, 1999: R. Rasmussen, J. Vivekanandan, J. Cole, B. Myers, and C. Masters. Journal of Applied Meteorology, Vol. 38, 1542 – 1563.

Observations of Visibility and Liquid Equivalent Snowfall Rate from the NCAR Marshall Field Site

Observations of Visibility and Liquid Equivalent Snowfall Rate from the NCAR Marshall Field Site Light ModHeavy

Theoretical Relationship between Visibility and Liquid Equivalent Snowfall Rate for Dry and Wet snow

Theoretical Relationship between Visibility and Liquid Equivalent Snowfall Rate for various crystal types and degree of riming.

Theory, Observations, and Accident Data Combined

Courtesy of APS Aviation Seven years of data from Montreal

Courtesy of APS Aviation Seven years of data from Montreal Light Moderate Heavy

Day vs Night Visibility Visibility at night is twice as good as the visibility during the day for the same snowfall rate Means that going from day to night decreases the snowfall rate from heavy to moderate, or from moderate to light. The LaGuardia accident (3/22/92) occurred at night –Occurred under wet snow conditions –Snow intensity of light –Occurred at night

Summary Both observations and theory show that a given visibility is not uniquely related to only one snowfall rate due to: –a variety of crystal types –varying degrees of riming –varying degrees of aggregation –wet snow –difference in visibility between day and night for a given extinction coefficient Above suggests that the variation in visibility during the previous deicing accidents is real and potentially misleading.

16 DECEMBER 2005 1137Z Reported Temperature, Precipitation: -8.0°C, Snow Snow intensity based on reported METAR visibility (1/2): Moderate APS Calculated rate of precipitation: 74.3 g/dm 2 /h Snow intensity based on rate: Heavy HOLDOVER TIME TABLES (MODERATE) Type IV: 25 to 55 Type I: 4 to 6 ACTUAL HOLDOVER TIME BASED ON RATE Type IV: +/- 10 Type I: +/- 2 ACTUAL REPORTED EVENT - YUL

FREQUENCY OF DE/ANTI-ICING OPERATIONS (ALL AIRPORTS) – SURVEY 2000-03

Visibility Criteria for Snow Intensity FAA TYPE I HOLDOVER TIME GUIDELINE Table 1. FAA Guideline for Holdover Times Anticipated for SAE Type I Fluid Mixture as a Function of Weather Conditions and OAT. CAUTION: THIS TABLE IS FOR DEPARTURE PLANING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. Outside Air Temperature ( OAT) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) CC FF Active Frost Freezing Fog Very Light Snow  Light Snow  Moderate Snow  **Freezing Drizzle Light Freezing Rain Rain on Cold Soaked Wing Other ‡ -3 and above 27 and above 0:45 0:11 - 0:17 0:18-0:220:11 - 0:180:06 - 0:110:09 - 0:13 0:02 - 0:05 0:02 - 0:05* CAUTIO N: No holdover time guideline s exist below -3 to –6 below 27 to 21 0:45 0:08 - 0:13 0:14-0:170:08 - 0:140:05 - 0:080:05 - 0:09 0:02 - 0:05 CAUTION: Clear ice may require touch for confirmation below -6 to –10 below 21 to 14 0:45 0:06 - 0:10 0:11-0:130:06 - 0:110:04 - 0:060:04 - 0:07 0:02 - 0:05 below -10 below 14 0:45 0:05 - 0:09 0:07-0:080:04 - 0:070:02 - 0:04 Effective: October 1, 2003 TABLE 1B. SNOWFALL INTENSITIES AS A FUNCTION OF PREVAILING VISIBILITY. FOR TYPE I HOLDOVER TIME GUIDELINES Time of Day Temp.Visibility (Statute Mile) (  C)(  F)  2 1/2 21 1/213/41/2  1/4 Day colder/equal colder/equal 30 Very Light Very Light Light Moderate Heav y Sno wfall Inten sity warmer than warmer than 30 Very Light Moderate Heavy Night colder/equal colder/equal 30 Very Light Moderate Heavy warmer than warmer than 30 Very Light ModerateHeavy NOTE: Based upon technical report, “The Estimation of Snowfall Rate Using Visibility,” Rasmussen, et al., Journal of Applied Meteorology, October 1999 and additional in situ data. HEAVY = Caution - no holdover time guidelines exist °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAE TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2A - FAA Guideline for Holdover Times Anticipated for KILFROST ABC-II PLUS Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 3,600cP, 20 o C, 0.3 RPM, Spindle LV2, 250ml beaker, 150ml fluid, 10 min. grd. leg. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:10-2:250:35-1:200:35-1:100:30-0:400:05-1:00CAUTION: No holdover time guidelines exist 75/25 6:001:10-2:250:35-1:100:30-1:000:20-0:400:05-0:50 50/50 4:000:15-0:450:20-0:400:05-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:10-2:250:25-0:550:35-1:100:30-0:40 75/25 5:001:10-2:250:25-0:500:30-1:000:20-0:40 50/50 3:000:15-0:450:15-0:350:05-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 8:000:30-1:050:15-0:35**0:15-0:45**0:10-0:30 75/25 5:000:20-0:550:15-0:35**0:15-0:30**0:10-0:20 below -14 to -25 below 7 to -13100/0 8:000:15-0:200:15-0:30 below -25below -13 100/0 Kilfrost ABC-II PLUS Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when Kilfrost ABC-II PLUS Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. KILFROST ABC-II PLUS TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2B - FAA Guideline for Holdover Times Anticipated for KILFROST ABC-2000 Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 2,350 cP, 20 o C, 0.3 RPM, Spindle LV2, 250ml beaker, 150ml fluid, 10 min. grd. leg. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:30-3:050:40-1:150:55-1:350:40-0:500:15-1:10CAUTION: No holdover time guidelines exist 75/25 6:001:40-3:300:40-1:150:45-1:150:40-0:500:15-1:40 50/50 4:001:00-2:100:15-0:300:15-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:30-3:050:30-1:000:55-1:350:40-0:50 75/25 5:001:40-3:300:30-1:050:45-1:150:40-0:50 50/50 3:001:00-2:100:15-0:300:15-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 8:000:35-1:250:25-0:45**0:25-0:50**0:10-0:30 75/25 5:000:35-1:150:25-0:50**0:25-0:55**0:15-0:30 below -14 to -25 below 7 to -13100/0 8:000:20-0:450:15-0:30 below -25below -13 100/0 Kilfrost ABC-2000 Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when Kilfrost ABC-2000 Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. KILFROST ABC-2000 TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2C - FAA Guideline for Holdover Times Anticipated for Octagon E-MAX II Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 13,520 cP, 20 o C, 0.3 RPM, Spindle LV1, 600 ml beaker, 500 ml fluid, 33 min 20 sec, grd. leg CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:002:05-3:450:45-1:300:45-1:350:30-0:400:15-1:30CAUTION: No holdover time guidelines exist 75/25 6:001:25-2:500:30-1:000:40-1:100:20-0:300:10-1:05 50/50 4:000:30-0:550:15-0:30 0:10-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:002:05-3:450:40-1:200:45-1:350:30-0:40 75/25 5:001:25-2:500:25-0:550:40-1:100:20-0:30 50/50 3:000:30-0:550:10-0:250:15-0:300:10-0:15 below -3 to -14 below 27 to 7100/0 8:000:50-1:450:35-1:10**0:35-1:00**0:20-0:30 75/25 5:000:30-1:200:25-0:50**0:35-1:05**0:15-0:30 below -14 to -25 below 7 to -13100/0 8:000:20-0:350:15-0:30 below -25below -13 100/0 Octagon E-MAX II Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when Octagon E-MAX II Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. OCTAGON E-MAX II TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2D – FAA Guideline for Holdover Times Anticipated for SPCA ECOWING 26 Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% fluid Tested 4,900cp, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 30 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:25-2:350:40-1:050:50-1:350:40-0:500:20-1:25CAUTION: No holdover time guidelines exist 75/25 6:001:05-1:550:30-0:500:45-1:050:25-0:350:10-1:00 50/50 4:000:30-0:450:10-0:200:15-0:250:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:25-2:350:40-1:000:50-1:350:40-0:50 75/25 5:001:05-1:550:25-0:450:45-1:050:25-0:35 50/50 3:000:30-0:450:10-0:200:15-0:250:05-0:10 below -3 to -14 below 27 to 7100/0 8:000:45-2:150:35-0:55**0:30-1:10**0:15-0:35 75/25 5:000:35-1:150:25-0:40**0:20-0:50**0:15-0:25 below -14 to -25 below 7 to -13100/0 8:000:25-0:450:30-0:50 below -25below -13 100/0 SPCA ECOWING 26 Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SPCA ECOWING 26 Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA ECOWING 26 TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2E – FAA Guideline for Holdover Times Anticipated for SAFEWING MP II 2025 Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% fluid Tested 5,500mPa.s, 20 o C, 0.3 rpm, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:30-2:050:45-1:200:40-1:000:25-0:350:10-1:15CAUTION: No holdover time guidelines exist 75/25 6:000:55-1:450:25-0:45 0:20-0:250:05-0:50 50/50 4:000:20-0:350:10-0:200:10-0:150:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:30-2:050:40-1:100:40-1:000:25-0:35 75/25 5:000:55-1:450:25-0:45 0:20-0:25 50/50 3:000:20-0:350:05-0:150:10-0:150:05-0:10 below -3 to -14 below 27 to 7100/0 8:000:45-1:500:35-1:00**0:35-1:05**0:20-0:35 75/25 5:000:40-1:200:25-0:45**0:30-0:40**0:15-0:25 below -14 to -25 below 7 to -13100/0 8:000:25-0:450:15-0:30 below -25below -13 100/0 SAFEWING MPII 2025 ECO Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING MPII 2025 Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA ECOWING 26 TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 FAA TYPE IV HOLDOVER TIME GUIDELINE TABLE 4 - FAA Guideline for Holdover Times Anticipated for SAE Type IV Fluid Mixtures as a Function of Weather Conditions and OAT. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/018:001:05-2:150:35-1:050:40-1:100:25-0:400:10-0:50CAUTION: No holdover time guidelines exist 75/256:001:05-1:450:30-1:050:35-0:500:15-0:300:05-0:35 50/504:000:15-0:350:05-0:200:10-0:200:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27100/012:001:05-2:150:30-0:550:40-1:100:25-0:40 75/255:001:05-1:450:25-0:500:35-0:500:15-0:30 50/503:000:15-0:350:05-0:150:10-0:200:05-0:10 below -3 to -14 below 27 to 7 100/012:000:20-1:200:20-0:40**0:20- 0:45 **0:10-0:25 75/255:000:25-0:500:20-0:35**0:15- 0:30 **0:10-0:20 below -14 to - 25 below 7 to -13 100/012:000:15-0:400:15-0:30 below - 25 below - 13 100/0SAE Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C(13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAE Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAE TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4A - FAA Guideline for Holdover Times Anticipated for UCAR ULTRA+ Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 36,000cP, 0 o C, 0.3 RPM, Spindle SC4-31/13R, 10ml fluid, 10 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:35-3:350:40-1:250:45-1:350:25-0:400:10-1:20CAUTION: No holdover time guidelines exist 75/25 50/50 CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:35-3:350:35-1:150:45-1:350:25-0:40 75/25 50/50 below -3 to -14 below 27 to 7100/0 12:001:25-3:000:25-0:55**0:45-1:25**0:30-0:45 75/25 below -14 to -24 below 7 to -12100/0 12:000:40-2:100:20-0:45 below -24below -12 100/0 UCAR ULTRA+ Type IV fluid may be used below –24 °C (-12 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when UCAR ULTRA+ Type IV fluid cannot be used. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:002:35-4:001:10-2:001:20-1:501:00-1:250:20-1:15CAUTION: No holdover time guidelines exist 75/25 6:001:05-1:450:30-1:050:45-1:100:35-0:500:10-0:50 50/50 4:000:20-0:350:05-0:200:15-0:200:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:002:35-4:001:00-1:401:20-1:501:00-1:25 75/25 5:001:05-1:450:30-0:550:45-1:100:35-0:50 50/50 3:000:20-0:350:05-0:150:15-0:200:05-0:10 below -3 to -14 below 27 to 7100/0 12:000:45-2:050:45-1:20**0:20-1:00**0:10-0:30 75/25 5:000:25-1:000:25-0:50**0:20-1:10**0:10-0:35 below -14 to -25 below 7 to -13100/0 12:000:20-0:400:40-1:10 below -25below -13 100/0 KILFROST ABC-S Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when KILFROST ABC-S Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. KILFROST ABC-S TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4D - FAA Guideline for Holdover Times Anticipated for SAFEWING MP IV 1957 Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 16,200cP, 20o, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:05-2:150:35-1:050:40-1:100:30-0:450:15-1:10CAUTION: No holdover time guidelines exist 75/25 6:001:10-2:100:35-1:05 0:25-0:400:10-1:00 50/50 4:000:25-0:500:15-0:300:15-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:05-2:150:30-0:550:40-1:100:30-0:45 75/25 5:001:10-2:100:30-0:500:35-1:050:25-0:40 50/50 3:000:25-0:500:10-0:200:15-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 12:000:45-1:300:30-0:50**0:35-0:55**0:20-0:35 75/25 5:000:25-1:100:20-0:40**0:25-0:55**0:15-0:30 below -14 to -25 below 7 to -13100/0 12:000:25-0:400:25-0:45 below -25below -13 100/0 SAFEWING  MP IV 1957 Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING MP IV 1957 Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAFEWING MP IV 1957 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4E – FAA Guideline for Holdover Times Anticipated for SAFEWING MP IV 2001 Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 18,000cP, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:20-3:201:55-2:000:55-1:550:40-1:000:15-2:00CAUTION: No holdover time guidelines exist 75/25 6:001:20-2:000:50-1:250:35-1:100:25-0:350:10-1:25 50/50 4:000:15-0:400:10-0:20 0:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:20-3:201:00-1:550:55-1:550:40-1:00 75/25 5:001:20-2:000:35-1:000:35-1:100:25-0:35 50/50 3:000:15-0:400:10-0:20 0:05-0:15 below -3 to -14 below 27 to 7100/0 12:000:45-1:350:30-0:50**0:55-1:35**0:30-0:45 75/25 5:000:30-1:000:20-0:35**0:40-1:10**0:20-0:30 below -14 to -25 below 7 to -13100/0 12:000:20-0:450:20-0:35 below -25below -13 100/0 SAFEWING  MP IV 2001 Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING  MP IV 2001 Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAFEWING MP IV 2001 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4F – FAA Guideline for Holdover Times Anticipated for CLARIANT SAFEWING MPIV 2012 PROTECT Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% fluid Tested 7,800cp, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:15-2:301:10-2:000:40-1:100:25-0:450:10-1:05CAUTION: No holdover time guidelines exist 75/25 6:001:10-2:050:35-1:100:35-0:500:15-0:300:05-0:40 50/50 4:000:25-0:450:15-0:250:15-0:200:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:15-2:300:40-1:150:40-1:100:25-0:45 75/25 5:001:10-2:050:25-0:550:35-0:500:15-0:30 50/50 3:000:25-0:450:15-0:250:15-0:200:05-0:10 below -3 to -14 below 27 to 7100/0 12:000:45-1:450:20-0:40**0:25-0:45**0:15-0:25 75/25 5:000:25-1:050:20-0:40**0:15-0:30**0:10-0:20 below -14 to -25 below 7 to -13100/0 12:000:20-0:450:15-0:30 below -25below -13 100/0 CLARIANT SAFEWING MP IV 2012 PROTECT TYPE IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when CLARIANT SAFEWING MP IV 2012 PROTECT TYPE IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. CLARIANT SAFEWING MP IV 2012 PROTECT TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4G - FAA Guideline for Holdover Times Anticipated for CLARIANT SAFEWING FOUR Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 6,400cP, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:50-2:450:45-1:451:05-1:450:50-1:050:10-1:20CAUTION: No holdover time guidelines exist 75/25 6:001:45-2:250:40-1:250:50-1:300:30-0:450:15-1:25 50/50 4:000:30-0:450:15-0:25 0:10-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:50-2:450:35-1:201:05-1:450:50-1:05 75/25 5:001:45-2:250:30-1:050:50-1:300:30-0:45 50/50 3:000:30-0:450:10-0:200:15-0:250:10-0:15 below -3 to -14 below 27 to 7100/0 12:000:30-1:300:25-0:55**0:25-1:05**0:15-0:30 75/25 5:000:30-1:050:20-0:45**0:20-0:50**0:15-0:25 below -14 to -25 below 7 to -13100/0 12:000:20-0:45 below -25below -13 100/0 CLARIANT SAFEWING FOUR Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when CLARIANT SAFEWING FOUR Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, hail  Snow includes snow grains CAUTIONS:  THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT.  SAFEWING  FOUR TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4H - FAA Guideline for Holdover Times Anticipated for CLARIANT SAFEWING MPIV 2030 ECO Type IV as a function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 10,500 mPa.s, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:55-3:200:50-1:350:55-2:000:40-0:500:15-1:40CAUTION: No holdover time guidelines exist 75/25 6:001:15-2:050:35-1:050:40-1:050:25-0:350:10-1:10 50/50 4:000:30-0:450:15-0:25 0:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:55-3:200:50-1:300:55-2:000:40-0:50 75/25 5:001:15-2:050:35-1:050:40-1:050:25-0:35 50/50 3:000:30-0:450:15-0:25 0:05-0:10 below -3 to -14 below 27 to 7100/0 12:000:50-2:000:45-1:25**0:30-1:10**0:20-0:35 75/25 5:000:40-1:300:35-1:05**0:35-1:20**0:15-0:30 below -14 to -25 below 7 to -13100/0 12:000:25-0:450:15-0:30 below -25below -13 100/0 CLARIANT SAFEWING MPIV 2030 ECO Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING MPIV 2030 ECO Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA AD-480 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4I - FAA Guideline for Holdover Times Anticipated for SPCA AD-480 Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 15,200cP, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 30 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:002:00-3:300:55-1:500:50-1:300:35-0:550:15-1:35CAUTION: No holdover time guidelines exist 75/25 6:001:30-2:450:40-1:200:50-1:150:30-0:450:10-1:15 50/50 4:000:30-0:450:15-0:300:15-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:002:00-3:300:40-1:200:50-1:300:35-0:55 75/25 5:001:30-2:450:30-1:050:50-1:150:30-0:45 50/50 3:000:30-0:450:10-0:200:15-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 12:000:20-1:200:30-0:55**0:25-1:20**0:15-0:30 75/25 5:000:25-0:500:20-0:45**0:25-1:05**0:15-0:30 below -14 to -25 below 7 to -13100/0 12:000:15-0:400:25-0:40 below -25below -13 100/0 SPCA AD-480 Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SPCA AD-480 Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA AD-480 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 5 - FAA Guidelines for the Application of SAE Type II and Type IV Fluid Mixtures. Minimum Concentrations as a Function of Outside Air Temperature (OAT). Concentrations in % V/V OATOne-step Procedure Deicing/Anti-icing Two-step Procedure First step: DeicingSecond step: Anti-icing 1 -3  C (27  F) and above 50/50 Heated 2 Type II/IV Water heated or a heated mix of Type I, II or IV with water 50/50 Type II/IV Below –3  C (27  F) to –14  C (7  F) 75/25 Heated 2 Type II/IV Heated suitable mix of Type I, Type II/IV, and water with FP not more than 3  C (5  F) above actual OAT 75/25 Type II/IV Below –14  C (7  F) to –25  C (-13  F) 100/0 Heated 2 Type II/IV Heated suitable mix of Type I, Type II/IV, and water with FP not more than 3  C (5  F) above actual OAT 100/0 Type II/IV Below –25  C (-13  F)SAE Type II/IV fluid may be used below –25  C (-13  F) provided that the freezing point of the fluid is at least a 7  C (13  F) below OAT and that aerodynamic acceptance criteria are met. Consider the use of SAE Type I when Type II/IV fluid cannot be used (see Table 1). 1) To be applied before first step fluid freezes, typically within 3 minutes. 2) Clean aircraft may be anti-iced with unheated fluid. NOTE: For heated fluids, a fluid temperature not less than 60  C (140  F) at the nozzle is desirable. Upper temperature limit shall not exceed fluid and aircraft manufacturers recommendations. CAUTIONS: Wing skin temperatures may differ and, in some cases, be lower than OAT. A stronger mix can be used under the latter conditions. As fluid freezing may occur, 50/50 Type II or IV fluid shall not be used for the anti-icing step of a cold-soaked wing as indicated by frost or ice on the lower surface of the wing in the area of the fuel tank. An insufficient amount of anti-icing fluid, especially in the second step of a two-step procedure, may cause a substantial loss of holdover time, particularly when using a Type I fluid mixture for the first step (deicing). Effective: October 1, 2003 Table 6. List of Qualified (1) Deicing/Anti-Icing Fluids – Winter 2003-2004 Qualified Type I Deicing/Anti-Icing Fluids Company NameFluid Name Aviation Xi’an High-TechKHF-1 Beijing Wangye Aviation Chem. Prod. Co. KLA-1 Battelle Memorial InstituteD 3 -1036 Deicing Fluid ClariantSafewing MPI 1938 ECO ClariantSafewing MPI 1938 PRE MIX ClariantSafewing MP I 1938 TF ClariantSafewing EG I 1996 Cryotech Deicing TechnologyDF Plus Cryotech Deicing TechnologyDF Plus (88) Delta PetroleumIce Away Dow Chemical CompanyUCAR  ADF Concentrate Dow Chemical CompanyUCAR  ADF 50/50 Dow Chemical CompanyUCAR  ADF XL-54 Dow Chemical CompanyUCAR  PG ADF Concentrate Dow Chemical CompanyUCAR  PG ADF 60/40 Home Oil Inc.SAFETEMP I PG 100 Home Oil Inc.SAFETEMP I ES InlandDuragly – P InlandDuragly – E Jarchem IndustriesJarKleer 1000 TF KilfrostKilfrost  DF KilfrostKilfrost  DF PLUS KilfrostKilfrost  DF PLUS (80) Lyondell Chemical Worldwide, IncARCOPlus Concentrate Lyondell Chemical Worldwide, IncARCOPlus Dilute Lyondell Chemical Worldwide, IncARCOPlus Canadian Dilute Metss CorporationADF-2 Newwave Aerochemical Co. Ltd.FCY-1A Octagon Process, IncOCTAFLO EG Octagon Process, IncOCTAFLO EF Sanshin Kagaku Kogyo Co.San-Ai ADF Type 1-A SPCASPCA DE-950 Table 6. List of Qualified (1) Deicing/Anti-Icing Fluids – Winter 2003-2004 (Continued) Qualified Type II Deicing/Anti-Icing Fluids Company NameFluid Name ClariantSafewing MP II 1951 ClariantSafewing MP II 2025 ECO KilfrostKilfrost  ABC-II PLUS KilfrostKilfrost  ABC-3 KilfrostKilfrost  ABC-2000 Octagon Process, IncOctagon E-Max SPCASPCA Ecowing 26 Qualified Type IV Deicing/Anti-Icing Fluids Company NameFluid Name ClariantSafewing MP IV 2030 ECO ClariantSafewing MP IV 1957 ClariantSafewing FOUR ClariantSafewing MP IV 2001 ClariantSafewing MP IV 2012 PROTECT Cryotech Deicing TechnologyKilfrost  ABC-S Kilfrost LimitedKilfrost  ABC-S Octagon Oct Ely-Chemical - Octagon Process, Inc. Max Flight SPCASPCA AD-480 Union Carb Dow Chemical CompanyUCAR  ADF/AAF ULTRA+ (1) NOTE: Qualified implies that the fluid has met the requirements of the applicable SAE AMS performance specifications, as conducted by the Anti-Icing Materials International Laboratory at the University of Quebec at Chicoutimi, Canada, in effect at the time of certification. Web site: http://www.uqac.uquebec.ca/amil/ It also implies that the fluid has completed HOT testing. Fluids that successfully qualify after the issuance of this list will appear in a later update. Time of Day Temp. Visibility (Statute Mile) (  C)(  F)  2 1/2 21 1/213/41/2  1/4 Day colder/equal colder/equal 30 Very Light Very Light Light Moderate Heavy Snow fall Inten sity warmer than warmer than 30 Very Light Moderate Heavy Night colder/equal colder/equal 30 Very Light Moderate Heavy warmer than warmer than 30 Very Light ModerateHeavy NOTE: Based upon technical report, “The Estimation of Snowfall Rate Using Visibility,” Rasmussen, et al., Journal of Applied Meteorology, October 1999 and additional in situ data. HEAVY = Caution - no holdover time guidelines exist

Modified Visibility Criteria for Snow Intensity Based on Temperature and Day or Night FAA TYPE I HOLDOVER TIME GUIDELINE Table 1. FAA Guideline for Holdover Times Anticipated for SAE Type I Fluid Mixture as a Function of Weather Conditions and OAT. CAUTION: THIS TABLE IS FOR DEPARTURE PLANING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. Outside Air Temperature ( OAT) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) CC FF Active Frost Freezing Fog Very Light Snow  Light Snow  Moderate Snow  **Freezing Drizzle Light Freezing Rain Rain on Cold Soaked Wing Other ‡ -3 and above 27 and above 0:45 0:11 - 0:17 0:18-0:220:11 - 0:180:06 - 0:110:09 - 0:13 0:02 - 0:05 0:02 - 0:05* CAUTIO N: No holdover time guideline s exist below -3 to –6 below 27 to 21 0:45 0:08 - 0:13 0:14-0:170:08 - 0:140:05 - 0:080:05 - 0:09 0:02 - 0:05 CAUTION: Clear ice may require touch for confirmation below -6 to –10 below 21 to 14 0:45 0:06 - 0:10 0:11-0:130:06 - 0:110:04 - 0:060:04 - 0:07 0:02 - 0:05 below -10 below 14 0:45 0:05 - 0:09 0:07-0:080:04 - 0:070:02 - 0:04 Effective: October 1, 2003 TABLE 1B. SNOWFALL INTENSITIES AS A FUNCTION OF PREVAILING VISIBILITY. FOR TYPE I HOLDOVER TIME GUIDELINES Time of Day Temp.Visibility (Statute Mile) (  C)(  F)  2 1/2 21 1/213/41/2  1/4 Day colder/equal colder/equal 30 Very Light Very Light Light Moderate Heav y Sno wfall Inten sity warmer than warmer than 30 Very Light Moderate Heavy Night colder/equal colder/equal 30 Very Light Moderate Heavy warmer than warmer than 30 Very Light ModerateHeavy NOTE: Based upon technical report, “The Estimation of Snowfall Rate Using Visibility,” Rasmussen, et al., Journal of Applied Meteorology, October 1999 and additional in situ data. HEAVY = Caution - no holdover time guidelines exist °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAE TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2A - FAA Guideline for Holdover Times Anticipated for KILFROST ABC-II PLUS Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 3,600cP, 20 o C, 0.3 RPM, Spindle LV2, 250ml beaker, 150ml fluid, 10 min. grd. leg. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:10-2:250:35-1:200:35-1:100:30-0:400:05-1:00CAUTION: No holdover time guidelines exist 75/25 6:001:10-2:250:35-1:100:30-1:000:20-0:400:05-0:50 50/50 4:000:15-0:450:20-0:400:05-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:10-2:250:25-0:550:35-1:100:30-0:40 75/25 5:001:10-2:250:25-0:500:30-1:000:20-0:40 50/50 3:000:15-0:450:15-0:350:05-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 8:000:30-1:050:15-0:35**0:15-0:45**0:10-0:30 75/25 5:000:20-0:550:15-0:35**0:15-0:30**0:10-0:20 below -14 to -25 below 7 to -13100/0 8:000:15-0:200:15-0:30 below -25below -13 100/0 Kilfrost ABC-II PLUS Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when Kilfrost ABC-II PLUS Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. KILFROST ABC-II PLUS TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2B - FAA Guideline for Holdover Times Anticipated for KILFROST ABC-2000 Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 2,350 cP, 20 o C, 0.3 RPM, Spindle LV2, 250ml beaker, 150ml fluid, 10 min. grd. leg. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:30-3:050:40-1:150:55-1:350:40-0:500:15-1:10CAUTION: No holdover time guidelines exist 75/25 6:001:40-3:300:40-1:150:45-1:150:40-0:500:15-1:40 50/50 4:001:00-2:100:15-0:300:15-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:30-3:050:30-1:000:55-1:350:40-0:50 75/25 5:001:40-3:300:30-1:050:45-1:150:40-0:50 50/50 3:001:00-2:100:15-0:300:15-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 8:000:35-1:250:25-0:45**0:25-0:50**0:10-0:30 75/25 5:000:35-1:150:25-0:50**0:25-0:55**0:15-0:30 below -14 to -25 below 7 to -13100/0 8:000:20-0:450:15-0:30 below -25below -13 100/0 Kilfrost ABC-2000 Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when Kilfrost ABC-2000 Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. KILFROST ABC-2000 TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2C - FAA Guideline for Holdover Times Anticipated for Octagon E-MAX II Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 13,520 cP, 20 o C, 0.3 RPM, Spindle LV1, 600 ml beaker, 500 ml fluid, 33 min 20 sec, grd. leg CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:002:05-3:450:45-1:300:45-1:350:30-0:400:15-1:30CAUTION: No holdover time guidelines exist 75/25 6:001:25-2:500:30-1:000:40-1:100:20-0:300:10-1:05 50/50 4:000:30-0:550:15-0:30 0:10-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:002:05-3:450:40-1:200:45-1:350:30-0:40 75/25 5:001:25-2:500:25-0:550:40-1:100:20-0:30 50/50 3:000:30-0:550:10-0:250:15-0:300:10-0:15 below -3 to -14 below 27 to 7100/0 8:000:50-1:450:35-1:10**0:35-1:00**0:20-0:30 75/25 5:000:30-1:200:25-0:50**0:35-1:05**0:15-0:30 below -14 to -25 below 7 to -13100/0 8:000:20-0:350:15-0:30 below -25below -13 100/0 Octagon E-MAX II Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when Octagon E-MAX II Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. OCTAGON E-MAX II TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2D – FAA Guideline for Holdover Times Anticipated for SPCA ECOWING 26 Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% fluid Tested 4,900cp, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 30 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:25-2:350:40-1:050:50-1:350:40-0:500:20-1:25CAUTION: No holdover time guidelines exist 75/25 6:001:05-1:550:30-0:500:45-1:050:25-0:350:10-1:00 50/50 4:000:30-0:450:10-0:200:15-0:250:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:25-2:350:40-1:000:50-1:350:40-0:50 75/25 5:001:05-1:550:25-0:450:45-1:050:25-0:35 50/50 3:000:30-0:450:10-0:200:15-0:250:05-0:10 below -3 to -14 below 27 to 7100/0 8:000:45-2:150:35-0:55**0:30-1:10**0:15-0:35 75/25 5:000:35-1:150:25-0:40**0:20-0:50**0:15-0:25 below -14 to -25 below 7 to -13100/0 8:000:25-0:450:30-0:50 below -25below -13 100/0 SPCA ECOWING 26 Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SPCA ECOWING 26 Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA ECOWING 26 TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 2E – FAA Guideline for Holdover Times Anticipated for SAFEWING MP II 2025 Type II Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% fluid Tested 5,500mPa.s, 20 o C, 0.3 rpm, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type II Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 12:001:30-2:050:45-1:200:40-1:000:25-0:350:10-1:15CAUTION: No holdover time guidelines exist 75/25 6:000:55-1:450:25-0:45 0:20-0:250:05-0:50 50/50 4:000:20-0:350:10-0:200:10-0:150:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 8:001:30-2:050:40-1:100:40-1:000:25-0:35 75/25 5:000:55-1:450:25-0:45 0:20-0:25 50/50 3:000:20-0:350:05-0:150:10-0:150:05-0:10 below -3 to -14 below 27 to 7100/0 8:000:45-1:500:35-1:00**0:35-1:05**0:20-0:35 75/25 5:000:40-1:200:25-0:45**0:30-0:40**0:15-0:25 below -14 to -25 below 7 to -13100/0 8:000:25-0:450:15-0:30 below -25below -13 100/0 SAFEWING MPII 2025 ECO Type II fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING MPII 2025 Type II fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA ECOWING 26 TYPE II FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 FAA TYPE IV HOLDOVER TIME GUIDELINE TABLE 4 - FAA Guideline for Holdover Times Anticipated for SAE Type IV Fluid Mixtures as a Function of Weather Conditions and OAT. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/018:001:05-2:150:35-1:050:40-1:100:25-0:400:10-0:50CAUTION: No holdover time guidelines exist 75/256:001:05-1:450:30-1:050:35-0:500:15-0:300:05-0:35 50/504:000:15-0:350:05-0:200:10-0:200:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27100/012:001:05-2:150:30-0:550:40-1:100:25-0:40 75/255:001:05-1:450:25-0:500:35-0:500:15-0:30 50/503:000:15-0:350:05-0:150:10-0:200:05-0:10 below -3 to -14 below 27 to 7 100/012:000:20-1:200:20-0:40**0:20- 0:45 **0:10-0:25 75/255:000:25-0:500:20-0:35**0:15- 0:30 **0:10-0:20 below -14 to - 25 below 7 to -13 100/012:000:15-0:400:15-0:30 below - 25 below - 13 100/0SAE Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C(13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAE Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAE TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4A - FAA Guideline for Holdover Times Anticipated for UCAR ULTRA+ Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 36,000cP, 0 o C, 0.3 RPM, Spindle SC4-31/13R, 10ml fluid, 10 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:35-3:350:40-1:250:45-1:350:25-0:400:10-1:20CAUTION: No holdover time guidelines exist 75/25 50/50 CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:35-3:350:35-1:150:45-1:350:25-0:40 75/25 50/50 below -3 to -14 below 27 to 7100/0 12:001:25-3:000:25-0:55**0:45-1:25**0:30-0:45 75/25 below -14 to -24 below 7 to -12100/0 12:000:40-2:100:20-0:45 below -24below -12 100/0 UCAR ULTRA+ Type IV fluid may be used below –24 °C (-12 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when UCAR ULTRA+ Type IV fluid cannot be used. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:002:35-4:001:10-2:001:20-1:501:00-1:250:20-1:15CAUTION: No holdover time guidelines exist 75/25 6:001:05-1:450:30-1:050:45-1:100:35-0:500:10-0:50 50/50 4:000:20-0:350:05-0:200:15-0:200:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:002:35-4:001:00-1:401:20-1:501:00-1:25 75/25 5:001:05-1:450:30-0:550:45-1:100:35-0:50 50/50 3:000:20-0:350:05-0:150:15-0:200:05-0:10 below -3 to -14 below 27 to 7100/0 12:000:45-2:050:45-1:20**0:20-1:00**0:10-0:30 75/25 5:000:25-1:000:25-0:50**0:20-1:10**0:10-0:35 below -14 to -25 below 7 to -13100/0 12:000:20-0:400:40-1:10 below -25below -13 100/0 KILFROST ABC-S Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when KILFROST ABC-S Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. KILFROST ABC-S TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4D - FAA Guideline for Holdover Times Anticipated for SAFEWING MP IV 1957 Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 16,200cP, 20o, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:05-2:150:35-1:050:40-1:100:30-0:450:15-1:10CAUTION: No holdover time guidelines exist 75/25 6:001:10-2:100:35-1:05 0:25-0:400:10-1:00 50/50 4:000:25-0:500:15-0:300:15-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:05-2:150:30-0:550:40-1:100:30-0:45 75/25 5:001:10-2:100:30-0:500:35-1:050:25-0:40 50/50 3:000:25-0:500:10-0:200:15-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 12:000:45-1:300:30-0:50**0:35-0:55**0:20-0:35 75/25 5:000:25-1:100:20-0:40**0:25-0:55**0:15-0:30 below -14 to -25 below 7 to -13100/0 12:000:25-0:400:25-0:45 below -25below -13 100/0 SAFEWING  MP IV 1957 Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING MP IV 1957 Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAFEWING MP IV 1957 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4E – FAA Guideline for Holdover Times Anticipated for SAFEWING MP IV 2001 Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 18,000cP, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:20-3:201:55-2:000:55-1:550:40-1:000:15-2:00CAUTION: No holdover time guidelines exist 75/25 6:001:20-2:000:50-1:250:35-1:100:25-0:350:10-1:25 50/50 4:000:15-0:400:10-0:20 0:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:20-3:201:00-1:550:55-1:550:40-1:00 75/25 5:001:20-2:000:35-1:000:35-1:100:25-0:35 50/50 3:000:15-0:400:10-0:20 0:05-0:15 below -3 to -14 below 27 to 7100/0 12:000:45-1:350:30-0:50**0:55-1:35**0:30-0:45 75/25 5:000:30-1:000:20-0:35**0:40-1:10**0:20-0:30 below -14 to -25 below 7 to -13100/0 12:000:20-0:450:20-0:35 below -25below -13 100/0 SAFEWING  MP IV 2001 Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING  MP IV 2001 Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SAFEWING MP IV 2001 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4F – FAA Guideline for Holdover Times Anticipated for CLARIANT SAFEWING MPIV 2012 PROTECT Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% fluid Tested 7,800cp, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:15-2:301:10-2:000:40-1:100:25-0:450:10-1:05CAUTION: No holdover time guidelines exist 75/25 6:001:10-2:050:35-1:100:35-0:500:15-0:300:05-0:40 50/50 4:000:25-0:450:15-0:250:15-0:200:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:15-2:300:40-1:150:40-1:100:25-0:45 75/25 5:001:10-2:050:25-0:550:35-0:500:15-0:30 50/50 3:000:25-0:450:15-0:250:15-0:200:05-0:10 below -3 to -14 below 27 to 7100/0 12:000:45-1:450:20-0:40**0:25-0:45**0:15-0:25 75/25 5:000:25-1:050:20-0:40**0:15-0:30**0:10-0:20 below -14 to -25 below 7 to -13100/0 12:000:20-0:450:15-0:30 below -25below -13 100/0 CLARIANT SAFEWING MP IV 2012 PROTECT TYPE IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when CLARIANT SAFEWING MP IV 2012 PROTECT TYPE IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. CLARIANT SAFEWING MP IV 2012 PROTECT TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4G - FAA Guideline for Holdover Times Anticipated for CLARIANT SAFEWING FOUR Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 6,400cP, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:50-2:450:45-1:451:05-1:450:50-1:050:10-1:20CAUTION: No holdover time guidelines exist 75/25 6:001:45-2:250:40-1:250:50-1:300:30-0:450:15-1:25 50/50 4:000:30-0:450:15-0:25 0:10-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:50-2:450:35-1:201:05-1:450:50-1:05 75/25 5:001:45-2:250:30-1:050:50-1:300:30-0:45 50/50 3:000:30-0:450:10-0:200:15-0:250:10-0:15 below -3 to -14 below 27 to 7100/0 12:000:30-1:300:25-0:55**0:25-1:05**0:15-0:30 75/25 5:000:30-1:050:20-0:45**0:20-0:50**0:15-0:25 below -14 to -25 below 7 to -13100/0 12:000:20-0:45 below -25below -13 100/0 CLARIANT SAFEWING FOUR Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when CLARIANT SAFEWING FOUR Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, hail  Snow includes snow grains CAUTIONS:  THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT.  SAFEWING  FOUR TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4H - FAA Guideline for Holdover Times Anticipated for CLARIANT SAFEWING MPIV 2030 ECO Type IV as a function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 10,500 mPa.s, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 15 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:001:55-3:200:50-1:350:55-2:000:40-0:500:15-1:40CAUTION: No holdover time guidelines exist 75/25 6:001:15-2:050:35-1:050:40-1:050:25-0:350:10-1:10 50/50 4:000:30-0:450:15-0:25 0:05-0:10CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:001:55-3:200:50-1:300:55-2:000:40-0:50 75/25 5:001:15-2:050:35-1:050:40-1:050:25-0:35 50/50 3:000:30-0:450:15-0:25 0:05-0:10 below -3 to -14 below 27 to 7100/0 12:000:50-2:000:45-1:25**0:30-1:10**0:20-0:35 75/25 5:000:40-1:300:35-1:05**0:35-1:20**0:15-0:30 below -14 to -25 below 7 to -13100/0 12:000:25-0:450:15-0:30 below -25below -13 100/0 CLARIANT SAFEWING MPIV 2030 ECO Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SAFEWING MPIV 2030 ECO Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA AD-480 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 4I - FAA Guideline for Holdover Times Anticipated for SPCA AD-480 Type IV Fluid Mixtures as a Function of Weather Conditions and OAT – Viscosity of Neat 100% Fluid Tested 15,200cP, 20 o C, 0.3 RPM, Spindle SC4-34/13R, 10ml fluid, 30 min. CAUTION: THIS TABLE IS FOR DEPARTURE PLANNING ONLY AND SHOULD BE USED IN CONJUNCTION WITH PRE-TAKEOFF CHECK PROCEDURES. OAT Manufacturer Specific Type IV Fluid Concentration Neat-Fluid/Water (Vol. %/Vol. %) Approximate Holdover Times Under Various Weather Conditions (hours: minutes) °C°FFrost*Freezing Fog Snow  Freezing Drizzle*** Light Freezing Rain Rain on Cold Soaked Wing Other ‡ above 0above 32 100/0 18:002:00-3:300:55-1:500:50-1:300:35-0:550:15-1:35CAUTION: No holdover time guidelines exist 75/25 6:001:30-2:450:40-1:200:50-1:150:30-0:450:10-1:15 50/50 4:000:30-0:450:15-0:300:15-0:250:05-0:15CAUTION: Clear ice may require touch for confirmation 0 to -332 to 27 100/0 12:002:00-3:300:40-1:200:50-1:300:35-0:55 75/25 5:001:30-2:450:30-1:050:50-1:150:30-0:45 50/50 3:000:30-0:450:10-0:200:15-0:250:05-0:15 below -3 to -14 below 27 to 7100/0 12:000:20-1:200:30-0:55**0:25-1:20**0:15-0:30 75/25 5:000:25-0:500:20-0:45**0:25-1:05**0:15-0:30 below -14 to -25 below 7 to -13100/0 12:000:15-0:400:25-0:40 below -25below -13 100/0 SPCA AD-480 Type IV fluid may be used below –25 °C (-13 °F) provided the freezing point of the fluid is at least 7 °C (13 °F) below the OAT and the aerodynamic acceptance criteria are met. Consider use of SAE Type I when SPCA AD-480 Type IV fluid cannot be used. °C = Degrees Celsius OAT = Outside Air Temperature °F = Degrees Fahrenheit VOL = Volume THE RESPONSIBILITY FOR THE APPLICATION OF THESE DATA REMAINS WITH THE USER. * During conditions that apply to aircraft protection for ACTIVE FROST ** No holdover time guidelines exist for this condition below -10  C (14  F) *** Use light freezing rain holdover times if positive identification of freezing drizzle is not possible ‡ Snow pellets, ice pellets, heavy snow, moderate and heavy freezing rain, and hail  Snow includes snow grains CAUTIONS: THE TIME OF PROTECTION WILL BE SHORTENED IN HEAVY WEATHER CONDITIONS. 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 BE REDUCED WHEN AIRCRAFT SKIN TEMPERATURE IS LOWER THAN OAT. SPCA AD-480 TYPE IV FLUID USED DURING GROUND DEICING/ANTI-ICING IS NOT INTENDED FOR AND DOES NOT PROVIDE PROTECTION DURING FLIGHT. Effective: October 1, 2003 TABLE 5 - FAA Guidelines for the Application of SAE Type II and Type IV Fluid Mixtures. Minimum Concentrations as a Function of Outside Air Temperature (OAT). Concentrations in % V/V OATOne-step Procedure Deicing/Anti-icing Two-step Procedure First step: DeicingSecond step: Anti-icing 1 -3  C (27  F) and above 50/50 Heated 2 Type II/IV Water heated or a heated mix of Type I, II or IV with water 50/50 Type II/IV Below –3  C (27  F) to –14  C (7  F) 75/25 Heated 2 Type II/IV Heated suitable mix of Type I, Type II/IV, and water with FP not more than 3  C (5  F) above actual OAT 75/25 Type II/IV Below –14  C (7  F) to –25  C (-13  F) 100/0 Heated 2 Type II/IV Heated suitable mix of Type I, Type II/IV, and water with FP not more than 3  C (5  F) above actual OAT 100/0 Type II/IV Below –25  C (-13  F)SAE Type II/IV fluid may be used below –25  C (-13  F) provided that the freezing point of the fluid is at least a 7  C (13  F) below OAT and that aerodynamic acceptance criteria are met. Consider the use of SAE Type I when Type II/IV fluid cannot be used (see Table 1). 1) To be applied before first step fluid freezes, typically within 3 minutes. 2) Clean aircraft may be anti-iced with unheated fluid. NOTE: For heated fluids, a fluid temperature not less than 60  C (140  F) at the nozzle is desirable. Upper temperature limit shall not exceed fluid and aircraft manufacturers recommendations. CAUTIONS: Wing skin temperatures may differ and, in some cases, be lower than OAT. A stronger mix can be used under the latter conditions. As fluid freezing may occur, 50/50 Type II or IV fluid shall not be used for the anti-icing step of a cold-soaked wing as indicated by frost or ice on the lower surface of the wing in the area of the fuel tank. An insufficient amount of anti-icing fluid, especially in the second step of a two-step procedure, may cause a substantial loss of holdover time, particularly when using a Type I fluid mixture for the first step (deicing). Effective: October 1, 2003 Table 6. List of Qualified (1) Deicing/Anti-Icing Fluids – Winter 2003-2004 Qualified Type I Deicing/Anti-Icing Fluids Company NameFluid Name Aviation Xi’an High-TechKHF-1 Beijing Wangye Aviation Chem. Prod. Co. KLA-1 Battelle Memorial InstituteD 3 -1036 Deicing Fluid ClariantSafewing MPI 1938 ECO ClariantSafewing MPI 1938 PRE MIX ClariantSafewing MP I 1938 TF ClariantSafewing EG I 1996 Cryotech Deicing TechnologyDF Plus Cryotech Deicing TechnologyDF Plus (88) Delta PetroleumIce Away Dow Chemical CompanyUCAR  ADF Concentrate Dow Chemical CompanyUCAR  ADF 50/50 Dow Chemical CompanyUCAR  ADF XL-54 Dow Chemical CompanyUCAR  PG ADF Concentrate Dow Chemical CompanyUCAR  PG ADF 60/40 Home Oil Inc.SAFETEMP I PG 100 Home Oil Inc.SAFETEMP I ES InlandDuragly – P InlandDuragly – E Jarchem IndustriesJarKleer 1000 TF KilfrostKilfrost  DF KilfrostKilfrost  DF PLUS KilfrostKilfrost  DF PLUS (80) Lyondell Chemical Worldwide, IncARCOPlus Concentrate Lyondell Chemical Worldwide, IncARCOPlus Dilute Lyondell Chemical Worldwide, IncARCOPlus Canadian Dilute Metss CorporationADF-2 Newwave Aerochemical Co. Ltd.FCY-1A Octagon Process, IncOCTAFLO EG Octagon Process, IncOCTAFLO EF Sanshin Kagaku Kogyo Co.San-Ai ADF Type 1-A SPCASPCA DE-950 Table 6. List of Qualified (1) Deicing/Anti-Icing Fluids – Winter 2003-2004 (Continued) Qualified Type II Deicing/Anti-Icing Fluids Company NameFluid Name ClariantSafewing MP II 1951 ClariantSafewing MP II 2025 ECO KilfrostKilfrost  ABC-II PLUS KilfrostKilfrost  ABC-3 KilfrostKilfrost  ABC-2000 Octagon Process, IncOctagon E-Max SPCASPCA Ecowing 26 Qualified Type IV Deicing/Anti-Icing Fluids Company NameFluid Name ClariantSafewing MP IV 2030 ECO ClariantSafewing MP IV 1957 ClariantSafewing FOUR ClariantSafewing MP IV 2001 ClariantSafewing MP IV 2012 PROTECT Cryotech Deicing TechnologyKilfrost  ABC-S Kilfrost LimitedKilfrost  ABC-S Octagon Oct Ely-Chemical - Octagon Process, Inc. Max Flight SPCASPCA AD-480 Union Carb Dow Chemical CompanyUCAR  ADF/AAF ULTRA+ (1) NOTE: Qualified implies that the fluid has met the requirements of the applicable SAE AMS performance specifications, as conducted by the Anti-Icing Materials International Laboratory at the University of Quebec at Chicoutimi, Canada, in effect at the time of certification. Web site: http://www.uqac.uquebec.ca/amil/ It also implies that the fluid has completed HOT testing. Fluids that successfully qualify after the issuance of this list will appear in a later update. Time of Day Temp. Visibility (Statute Mile) (  C)(  F)  2 1/2 21 1/213/41/2  1/4 Day colder/equal colder/equal 30 Very Light Very Light Light Moderate Heavy Snow fall Inten sity warmer than warmer than 30 Very Light Moderate Heavy Night colder/equal colder/equal 30 Very Light Moderate Heavy warmer than warmer than 30 Very Light ModerateHeavy NOTE: Based upon technical report, “The Estimation of Snowfall Rate Using Visibility,” Rasmussen, et al., Journal of Applied Meteorology, October 1999 and additional in situ data. HEAVY = Caution - no holdover time guidelines exist

PROBABILITY OF SNOW IN EACH HOT TABLE TEMPERATURE RANGE – TYPE I FLUIDS

The liquid equivalent rate of snow, freezing rain, snow pellets, ice pellets, and freezing drizzle is the primary factor causing aircraft deicing fluids to fail. The current NWS estimates of snowfall and drizzle intensity available to pilots via METARS through ASOS and ATIS is based on visibility, not liquid equivalent. The use of a modified visibility table is only a stop- gap measure. Need real-time liquid equivalent! The lack of liquid equivalent and precipitation type real-time information updated every minute is having a significant impact on aircraft deicing operations and is a significant safety factor

Hotplate (Yankee) Weighing Snowgauge (GEONOR) Liquid Water Equivalent Measurements ASOS weighing precipitation gauge (AWPAG) Manufactured by OTT

 CHANGE PARAGRAPH 2.6.6 TO INCLUDE CHANGES APPROVED BY ACCB AND APMC?  2.6.6 Algorithms Used by Automated Stations. Automated stations shall use algorithms that conform with the latest Federal Standard Algorithms for Automated Weather Observing Systems published by the OFCM, or subsequently approved by the ASOS Configuration Control Board and ASOS Program Management Council. These algorithms do not apply to previously authorized systems, which may continue to operate until replaced or modified.  8.4 Present Weather Observing Standards  8.4.1 Qualifiers. Present weather qualifiers fall into two categories: intensity or proximity and descriptors. Qualifiers may be used in various combinations to describe weather phenomena.  a. Intensity/Proximity. The intensity qualifiers are: light, moderate, and heavy. The proximity qualifier is vicinity.  (1) Intensity of Precipitation. When more than one form of precipitation is occurring at a time or precipitation is occurring with an obscuration, the intensities determined shall be no greater than that which would be determined if any forms were occurring alone. The intensity of precipitation shall be identified as light, moderate, or heavy in accordance with one of the following:

SHOULD WE CHANGE INTENSITY OF SNOW AND DRIZZLE AS FOLLOWS?  (b) Intensity of Snow and Drizzle. The manually-derived intensity of snow and drizzle shall be based on the reported surface visibility in accordance with Table 8-6, when occurring alone. Where possible, the intensity of snow or drizzle may be automatically determined by sensors operating in accordance with the Federal Standard Algorithms for Automated Observing Systems Used for Aviation Purposes using a liquid water equivalent rate.  Table 8-4. Intensity of Snow Based on Liquid Water Equivalent Rate  IntensityCriteria   LightLess than 1 mm*/hr   Moderate1 – 2.5 mm*/hr   HeavyGreater than 2.5 mm*/hr   Table 8-6. Estimating Intensity of Snow or Drizzle Based on Visibility   Intensity Criteria   Light Visibility > 1/2 mile.   Moderate Visibility > 1/4 mile but < 1/2 mile.   Heavy Visibility < 1/4 mile.

 Proposed change #2:  2.5.2 Aviation Selected Special Weather Report (SPECI)  a. Criteria for SPECI  CHANGE  (6) PRECIPITATION.  (a) hail begins or ends.  (b) freezing precipitation begins, ends, or changes intensity.  (c) ice pellets begin, end, or change intensity.  TO  (6) PRECIPITATION.  (a) hail begins or ends.  (b) freezing precipitation begins, ends, or changes intensity.  (c) ice pellets begin, end, or change intensity.  (d) snow begins, ends or changes intensity.

Freezing drizzle

Intensity FMH-1 Criteria for Drizzle Intensity 1 FZDZ Accretion Rate Criteria 2 LightVisibility > ½ mileRate ≤ 0.25 mm/hr (0.01 in/hr) ModerateVisibility > ¼ mile but ≤ ½ mile Rate > 0.25 mm/hr but ≤ 0.5 mm/hr HeavyVisibility ≤ ¼ mileRate > 0.5 mm/hr (0.02 in/hr) Criteria for Determining Freezing Drizzle Intensity 1 Federal Meteorological Handbook 2 Glossary of the American Meteorological Society

Remarks on Current Methods to Estimate Freezing Drizzle Intensity Currently used method to estimate drizzle intensity (light, moderate, or heavy) reported on METAR’s is based on visibility. This is true both with the U.S. National Weather Service, and also internationally.

Remarks on Current Methods to Estimate Freezing Drizzle Intensity Report by Allan Ramsay prepared for the U.S. National Weather Service ASOS program (Sept. 21, 1999) has shown that the use of visibility to estimate drizzle intensity is highly inaccurate in terms of the actual ice accretion rate on an exposed surface.

ASOS Present Weather Sensor LEDWI Optical Scientific Inc. Rosemount Icing Sensor Model 872C3

Freezing Drizzle Heating cycles Frequency drop due to ice accretion on the sensor

Ramsay Algorithm for FZRA/FZDZ Ice DetectorLEDWI Present Wx Type TempVisibilitySky Cover Present Weather Reported Accretion Frequency < 39,967 Hz and 15 min Accretion Rate >13 Hz in 15 min RA,UP<2.8 C (<37°F) Any FZRA SNAny SN Accretion Frequency < 39,967 Hz and 15 min Accretion Rate >6 Hz in 15 min No Precip < 0 C (<32°F) AnyOVCFZDZ Not OVC None Accretion Frequency < 39,967 Hz No Precip < 0 C (<32°F) > 7 miles CLR or SCT FROST

Icing Rates Generally based on rate per 15 minutes.01 inch/hour = 66 Hz/hour = 16.5 Hz/15 min FZFG.001 -.004 in/hr1 – 5 Hz/15 min LightFZDZ.004 -.01 in/hr6 – 16 Hz/15 min MDTFZDZ.01 -.02 in/hr17 – 33 Hz/15 min HeavyFZDZ>.02 in/hr> 33 Hz/15 min

One minute freezing drizzle observations from ASOS sites with freezing rain sensors at various locations in the U.S. from 1998-99 (Analysis by Al Ramsey, formerly of Raytheon). Freezing Drizzle Intensity Minutes

Freezing Drizzle Intensity Percent of time One minute freezing drizzle observations from ASOS sites with freezing rain sensors at various locations in the U.S. from 1998-99 (Analysis by Al Ramsey, formerly of Raytheon).

Freezing Drizzle Intensity Quotes from the Al Ramsey report to the U.S. National Weather Service: “It is clear that visibility-based criteria provide little or no information on the intensity of ice accretion from freezing drizzle.” “…data collected in this project clearly indicate that METAR/SPECI reports of FZDZ intensity, based on visibility, do not accurately represent the rate of ice accretion, and they may mislead users into selecting incorrect holdover times.”

Freezing drizzle ingest into engines can cause significant damage to fan blades (light freezing drizzle reported by METAR, heavy freezing drizzle actually occuring based on liquid equivalent)

Recent Impacts of Freezing Drizzle on Aircraft Taxiing for Takeoff On Oct. 31, 2002, eleven United 737 jet engines damaged to due ingestion of freezing drizzle at Denver International Airport. Observer reported light snow, however, if reported correctly would have been light drizzle by visibility. Ramsey algorithm indicated heavy freezing drizzle during most of the event. Cost to United: $2 Million. On Feb. 7, 2003, six Brathens 737 jet engines damaged due to the ingestion of freezing drizzle at Gardemoen Airport in Oslo, Norway. Observer reported light freezing drizzle. Actual rate was likely heavy, however, based on ice accretion observed on cars and other structures. On Oct. 30, 31 2003, an additional seven United 737 jet engines damaged due to ingestion of freezing drizzle at Denver International Airport. Observer reported light freezing drizzle, Ramsey algorithm indicated heavy freezing drizzle for most of the event. Cost to United: $850K.

PRECIPITATION RATE ANALYSIS NATURAL SNOW - ABOVE 0ºC Shows that most of heavy snow occurs at rates < 50g/dm 2 /h Heavy snow

CUMULATIVE PRECIPITATION RATE ANALYSIS NATURAL SNOW ABOVE 0ºC

Hotplate Snow Gauge  No moving parts, wind shields or anti- freeze  Measurement range – 0-20 mm/hr  LWE accuracy +/- 0.25 mm/hr  Minimum rate detection – 0.25 mm/hr  Resolution – 0.1 mm/hr  Currently used for Minneapolis WSDDM System  Provides 1-minute precipitation rates

GEONOR Precipitation Gauge  Weighing Gauge using vibrating wire technology  Resolution – 0.1 mm/hr  Capacity - 0 – 600 mm  Requires wind shield, glycol  Currently used for DIA WSDDM system  Provides 1-minute precipitation accumulations

SHOULD WE CHANGE INTENSITY OF SNOW AND DRIZZLE AS FOLLOWS?  (b) Intensity of Snow and Drizzle. The manually-derived intensity of snow and drizzle shall be based on the reported surface visibility in accordance with Table 8-6, when occurring alone. Where possible, the intensity of snow or drizzle may be automatically determined by sensors operating in accordance with the Federal Standard Algorithms for Automated Observing Systems Used for Aviation Purposes using a liquid water equivalent rate.  Table 8-5. Intensity of Freezing Drizzle Based on Liquid Water Equivalent Rate  IntensityCriteria  LightLess than 0.254 mm*/hr  Moderate0.254 – 0.508 mm*/hr  HeavyGreater than 0.508 mm*/hr  Table 8-6. Estimating Intensity of Snow or Drizzle Based on Visibility  Intensity Criteria  Light Visibility > 1/2 mile.  Moderate Visibility > 1/4 mile but 1/4 mile but < 1/2 mile.  Heavy Visibility < 1/4 mile.

On the use of Liquid Water Equivalent (LWE) for estimating snowfall intensity and freezing drizzle intensity versus the use of visibility Roy Rasmussen.

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On the use of Liquid Water Equivalent (LWE) for estimating snowfall intensity and freezing drizzle intensity versus the use of visibility Roy Rasmussen.

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Presentation on theme: "On the use of Liquid Water Equivalent (LWE) for estimating snowfall intensity and freezing drizzle intensity versus the use of visibility Roy Rasmussen."— Presentation transcript:

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