SAE AS 6286 4-2016 Weather.pdf

1、_SAE Technical Standards Board Rules provide that: “This report is published by SAE to advance the state of technical and engineering sciences. The use of this report is entirely voluntary, and its applicability and suitability for any particular use, including any patent infringement arising theref

2、rom, is the sole responsibility of the user.”SAE reviews each technical report at least every five years at which time it may be revised, reaffirmed, stabilized, or cancelled. SAE invites your written comments and suggestions.Copyright 2016 SAE InternationalAll rights reserved. No part of this publi

3、cation may be reproduced, stored in a retrieval system or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without the prior written permission of SAE.TO PLACE A DOCUMENT ORDER: Tel: 877-606-7323 (inside USA and Canada)Tel: +1 724-776-4970 (out

4、side USA)Fax: 724-776-0790Email: CustomerServicesae.orgSAE WEB ADDRESS: http:/www.sae.orgSAE values your input. To provide feedback on thisTechnical Report, please visithttp:/standards.sae.org/AS6286/4AEROSPACESTANDARDAS6286/4Issued 2016-11Superseding ARP5149BWeatherRATIONALEThis document covers the

5、 standards for training and qualifying staff related to the different aspects of deicing/anti-icing of aircraft on the ground.In conjunction with the main document AS6286 and other related slash sheets it will provide training and qualification standards to set up a proper training and qualification

6、 program to deice and anti-ice aircraft on the ground. Information to support this training program is provided to make the material a better tool for the preparation and execution of the training and qualification. It is intended to provide a common basis for deicing/anti-icing training and qualifi

7、cation for deicingproviders and airlines. This material was compiled using various international documents with support from SAE documents and individually contributed editorial comments. Its purpose is to serve as a “Globalized Deicing Training Manual”.The document is intended to promote and develo

8、p safe practices, effective procedures, and improved technology related to training of aircraft ground operations in winter conditions to ensure the highest possible levels of safety for passengers,flight crew and ground personnel.It shall ensure continued compliance with all relevant standards and

9、regulatory requirements, and shall ensure that it continues to reflect current industry best practice.It shall contribute to develop training standards and specifications related to the deicing/anti-icing of aircraft on the ground in conjunction with international standards organizations. The docume

10、nt shall support the preparation of training material for aircraft ground deicing/anti-icing purposes, harmonized with other organizations in the aircraft ground deicing/anti-icing field (for example SAE, ISO, IATA, ICAO, and regulatory authorities).FOREWORDThis manual is intended to provide a commo

11、n basis for deicing/anti-icing training and qualification for deicing providers and airlines. Each organization involved is responsible for complying with local regulations and requirements imposed by manufacturers of aircraft, equipment, and fluids, by regulatory and environmental authorities.This

12、manual is divided in two parts:1. Training and qualification standards, including the scope of trainingand2. Overview and background information about deicing/anti-icing procedures and related subjects.SAE INTERNATIONAL AS6286/4 Page 2 of 11TABLE OF CONTENTS1. SCOPE 31.1 Field of Application 32. REF

13、ERENCES 32.1 Applicable Documents 32.2 Definitions and Abbreviations . 33. AIRCRAFT SURFACE CONTAMINATION RECOGNITION 34. BACKGROUND INFORMATION 34.1 Weather. 34.1.1 Relevant Weather Aspects 34.1.2 Weather Terminology 44.1.3 Explanation of Weather Terms . 44.2 Interpreting Weather Data. 74.2.1 METAR

14、 74.2.2 TAF 84.3 Ice Formation 84.3.1 Areas of Ice Build-Up 84.3.2 Hazards of Ice on Aircraft 94.3.3 Frost Formation. 94.4 Weather Effects on Aircraft Operations 104.4.1 Weather Categories 104.5 Weather Effects on Fluid Behavior . 115. NOTES 115.1 Revision Indicator 11SAE INTERNATIONAL AS6286/4 Page

15、 3 of 111. SCOPE1.1 Field of ApplicationThis document shall be used in conjunction with:- AS6286, Training and Qualification Program for Deicing/Anti-icing of Aircraft on the Ground- AS6286/1, Processes including Methods- AS6286/2, Equipment- AS6286/3, Fluids- AS6286/5, Health, Safety and First Aid-

16、 AS6286/6, Aircraft Deicing/Anti-icing Diagrams, No-Spray-Zones2. REFERENCES2.1 Applicable DocumentsRefer to AS6286 main document Section 2 for all applicable and related publications.2.2 Definitions and AbbreviationsRefer to AS6285 Aircraft Ground Deicing/Anti-icing Processes.3. AIRCRAFT SURFACE CO

17、NTAMINATION RECOGNITIONAnti-icing fluid has lost its effectiveness when any wing surface changes from a smooth, clean, glossy surface to one on which frost, slush, snow, or ice can be seen as no longer being absorbed by the fluid. This includes random snow accumulation or a graying/dulling of the su

18、rface reflectivity caused by fluid deterioration. Loss of effectiveness may occur quickly with Type I fluid. Leading and trailing edges tend to fail first, as well as the downwind wing in a crosswind environment.CAUTION: Under conditions of rain (falling on cold aircraft surfaces), freezing rain, or

19、 freezing drizzle, it is extremely difficult to determine whether a glossy wing surface is due to ice, (especially clear ice), or the presence of Type I/II/III/IV fluid. If the flight crew is unable to determine if ice is present, request either a pre-takeoff contamination check (when available) or

20、conduct another aircraft deicing/anti-icing treatment.4. BACKGROUND INFORMATION4.1 Weather4.1.1 Relevant Weather AspectsWeather is complex and at times difficult to understand. Our restless atmosphere is almost constantly in motion as it strivesto reach equilibrium. These never-ending air movements

21、set up chain reactions, which culminate in a continuing variety of weather. The climate of any particular region is largely determined by the amount of energy received from the sun, but the local geography of the area also influences the climate. We are prepared to face “problems” in areas where win

22、ter isunavoidable but there can be a hidden danger at regions where winter weather aspects are not so obvious. The main point is to be aware of how, where, and why ice, in its different forms (and relating forms of frost and snow), can build up.SAE INTERNATIONAL AS6286/4 Page 4 of 114.1.2 Weather Te

23、rminologyWeather terminology can be seen and heard from various weather information sources. The general terms are standardized and they are adapted in the same way everywhere. Weather information is essential for the deicing crew in the sense that official temperature and weather characters must be

24、 obtained for proper analysis of deicing, anti-icing, mixture, and holdover time procedures. Weather abbreviations can be found in AS6285 Section 3.The intensity can be marked as light (-) or heavy (+), otherwise it is considered moderate intensity (no marking).NOTE: Intensity in MET reports is defi

25、ned according to horizontal visibility. The actual accumulation of precipitation and horizontal visibility may in some cases not be comparable and therefore caution must be taken when interpreting the intensity.4.1.3 Explanation of Weather Terms4.1.3.1 Active FrostActive frost is a condition when fr

26、ost is forming. Active frost occurs when aircraft surface temperature is at or below 0 C (32 F) and at or below dew point.4.1.3.2 Change of StateThe transformation of water from one form (e.g., solid (ice), liquid, or gaseous (water vapor), to any other form).- Condensation: the change of water vapo

27、r to liquid- Evaporation: the change of liquid water to water vapor- Freezing: the change of liquid water to ice- Melting: the change of ice to liquid water- Sublimation: the change of (1) ice to water vapor or (2) water vapor to ice (also called deposition)4.1.3.3 Clear IceThe formation of a layer

28、or mass of ice which is relatively transparent because of its homogeneous structure and smallnumber and size of air spaces. Factors, which favor clear icing, are large drop size, rapid accretion of super cooled water and slow dissipation of latent heat of fusion. Aircraft are most vulnerable to this

29、 type of build-up, when:(a) wing temperatures remain well below 0 C (32 F) during the turnaround/transit(b) ambient temperatures between -2 C and +15 C are experienced(c) precipitation occurs while aircraft is on the ground and/or(d) frost or ice is present on lower surface of either wing.NOTE: Clea

30、r ice can form at other temperatures if conditions (a), (c), and (d) exist.SAE INTERNATIONAL AS6286/4 Page 5 of 114.1.3.4 Cold-Soak EffectThe wings of aircraft are said to be “cold-soaked” when they contain very cold fuel as a result of having just landed after aflight at high altitude or from havin

31、g been re-fueled with very cold fuel. Whenever precipitation falls on a cold-soaked aircraftwhen on the ground, clear icing may occur. Even in ambient temperatures between -2 C (28 F) and +15 C (59 F), ice or frost can form in the presence of visible moisture or high humidity if the aircraft structu

32、re remains at 0 C (32 F) or below. Clear ice is very difficult to be detected visually and may break loose during or after takeoff. The following factors contribute to cold-soaking: temperature and quantity of fuel in fuel cells, type and location of fuel cells, length of time at high altitude fligh

33、ts, temperature of re-fueled fuel, and time since re-fueling.4.1.3.5 Cold FrontAny non-occluded front, which moves in such a way that colder air replaces warmer air.4.1.3.6 Dew PointThe temperature to which a sample of air must be cooled, while the amount of moisture and barometric pressure remain c

34、onstant, in order to attain saturation with respect to water.4.1.3.7 DrizzleA form of precipitation. Very small water droplets (diameter less than 0.5 mm) that appear to float with the air currents while falling in an irregular path (unlike rain, which fall in a comparatively straight path, and unli

35、ke fog droplets which remain suspended in the air).4.1.3.8 Freezing DrizzleFairly uniform precipitation composed exclusively of fine droplets (diameter less than 0.5 mm (0.02 inch) very close together which freezes upon impact with the ground or other exposed objects.4.1.3.9 Freezing FogA suspension

36、 of numerous minute water droplets that freeze upon impact with ground or other exposed objects, generally reducing the horizontal visibility at the earths surface to less than 1 km (5/8 mile).4.1.3.10 Frost/Hoar FrostIce crystals that form from ice saturated air at temperatures below 0 C (32 F) by

37、direct deposition on the ground or other exposed objects.4.1.3.11 HailPrecipitation of small balls or pieces of ice with a diameter ranging from 5 to 50 mm (0.2 to 2.0 inches) falling either separately or agglomerated.4.1.3.12 Ice Pellets/Small HailPrecipitation of transparent (grains of ice), or tr

38、anslucent (small hail) pellets of ice, which are spherical or irregular, and which have a diameter of 5 mm (0.2 inch) or less. The pellets of ice usually bounce when hitting hard ground.4.1.3.13 Light* Freezing RainPrecipitation of liquid water particles which freezes upon impact with the ground or

39、other exposed objects, either in the form of drops of more than 0.5 mm (0.02 inch) or smaller drops which, in contrast to drizzle, are widely separated. Measuredintensity of liquid water particles is up to 2.5 mm/hour (0.10 inch/hour) or 25 grams/dm2/hour with a maximum of 0.25 mm (0.01 inch) in 6 m

40、inutes.SAE INTERNATIONAL AS6286/4 Page 6 of 114.1.3.14 Lowest Operational Use Temperature (LOUT)The lowest operational use temperature (LOUT) is the higher (warmer) of the lowest temperature at which the fluid meets the aerodynamic acceptance test (according to AS5900) for a given type (high speed o

41、r low speed) of aircraftorThe freezing point of the fluid plus the freezing point buffer of 10C for Type I fluid and 7C for Type II, III or IV fluids.NOTE: For applicable values refer to the fluid manufacturers documentation.4.1.3.15 Moderate* and Heavy* Freezing RainPrecipitation of liquid water pa

42、rticles which freezes upon impact with the ground or other exposed objects, either in the form of drops of more than 0.5 mm (0.02 inch) or smaller drops which, in contrast to drizzle, are widely separated. Measuredintensity of liquid water particles is more than 2.5 mm/hour (0.10 inch/hour) or 25 gr

43、ams/dm2/hour.4.1.3.16 Rain or High Humidity (on Cold Soaked Wing)Water, visible moisture, or humidity forming ice or frost on the wing surface, when the temperature of the aircraft wing surface is at or below 0 C (32 F).4.1.3.17 Rain and SnowPrecipitation in the form of a mixture of rain and snow.4.

44、1.3.18 Relative HumidityThe ratio of the existing amount of water vapor in the air at a given temperature to the maximum amount that could exist at that temperature (usually expressed in percent).4.1.3.19 SaturationThe condition of the atmosphere when actual water vapor present is the maximum possib

45、le at existing temperatures.4.1.3.20 SnowPrecipitation of ice crystals, most of which are branched, star-shaped, or mixed with unbranched crystals. At temperatures higher than -5 C (23 F), the crystals are generally agglomerated into snowflakes.4.1.3.21 Snow GrainsPrecipitation of very small white a

46、nd opaque particles of ice that are fairly flat or elongated with a diameter of less than 1 mm (0.04 inch). When snow grains hit hard ground, they do not bounce or shatter.4.1.3.22 Snow PelletsPrecipitation of white, opaque particles of ice. The particles are round or sometimes conical; their diamet

47、er range fromabout 2 to 5 mm (0.08 to 0.2 inch). Snow pellets are brittle, easily crushed; they do bounce and may break on hardground.NOTE: For holdover time purposes treat snow pellets as snow.SAE INTERNATIONAL AS6286/4 Page 7 of 114.1.3.23 SlushSnow or ice that has been reduced to a soft watery mi

48、xture by rain, warm temperatures, and/or chemical treatment.4.1.3.24 Warm FrontAny non-occluded front, which moves in such a way that warmer air replaces colderair.4.1.3.25 Water VaporWater in the invisible gaseous form.*NOTE: Intensity in MET reports is defined according to horizontal visibility.4.

49、2 Interpreting Weather DataWeather information can be gathered from various sources. Some of this written information can be difficult to understandat times, but they all follow the same logic. As for the deicing crew, temperature, dew point, precipitation, intensity, andforecast information are elements that affect the operation. Some of these terms are explained below as well as an example of a local meteorologic