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Aem Series, 03. Aviation Hazards

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Aem Series, 03. Aviation Hazards AeM SERIES No. 3 Aviation Hazards Commission for Aeronautical Meteorology WEATHER CLIMATE WATER CLIMATE WEATHER AeM SERIES No. 3 Aviation Hazards Commission for Aeronautical Meteorology WEATHER CLIMATE WATER CLIMATE WEATHER © World Meteorological Organization, 2018 The right of publication in print, electronic and any other form and in any language is reserved by WMO. Short extracts from WMO publications may be reproduced without authorization, provided that the complete source is clearly indicated. Editorial correspondence and requests to publish, reproduce or translate this publication in part or in whole should be addressed to: Chair, Publications Board World Meteorological Organization (WMO) 7 bis, avenue de la Paix Tel.: +41 (0) 22 730 84 03 P.O. Box 2300 Fax: +41 (0) 22 730 80 40 CH-1211 Geneva 2, Switzerland E-mail: [email protected] NOTE The designations employed in WMO publications and the presentation of material in this publication do not imply the expression of any opinion whatsoever on the part of WMO concerning the legal status of any country, territory, city or area, or of its authorities, or concerning the delimitation of its frontiers or boundaries. The mention of specific companies or products does not imply that they are endorsed or recommended by WMO in preference to others of a similar nature which are not mentioned or advertised. The findings, interpretations and conclusions expressed in WMO publications with named authors are those of the authors alone and do not necessarily reflect those of WMO or its Members. This publication has been issued without formal editing. TABLE OF CONTENTS Page 1. INTRODUCTION........................................................................................................................... 1 2. TUR BULE NCE AND WIND SHEAR ....................................................................................... 1 2.1 TURBULENCE DUE TO CONVECTION - CONVECTIVE TURBULENCE ............................................2 2.1.1 Description ....................................................................................................................... 2 2.1.2 Effects on Aircraft ............................................................................................................. 2 2.1.3 Diagnosis of Hazard Using Appropriate Imagery............................................................... 4 2.1.4 Empirical Forecasting Techniques .................................................................................... 4 2.1.5 Associated NWP products.................................................................................................. 5 2.1.6 A Brief Study of Two Cases................................................................................................ 5 2.2 MECHANICAL TURBULENCE ................................................................................................... 8 2.2.1 Description........................................................................................................................ 8 2.2.2 Effects on Aircraft ............................................................................................................. 8 2.2.3 Diagnosis of Turbulence Using Appropriate Imagery......................................................... 8 2.2.4 Empirical forecasting techniques....................................................................................... 9 2.2.5 Associated NWP products.................................................................................................. 9 2.3 OROGRAPHIC TURBULENCE .................................................................................................... 9 2.3.1 Description ....................................................................................................................... 9 2.3.2 Effects on Aircraft ........................................................................................................... 13 2.3.3 Diagnosis of Hazard Using Appropriate Imagery............................................................. 14 2.3.4 Empirical Forecasting Techniques .................................................................................. 15 2.3.5 Associated NWP products................................................................................................ 15 2.4 CLEAR AIR TURBULENCE (CAT) .......................................................................................... 15 2.4.1 Description ..................................................................................................................... 15 2.4.2 Effects on Aircraft ........................................................................................................... 16 2.4.3 Diagnosis of Hazard Using Appropriate Imagery............................................................. 16 2.4.4 Empirical Forecasting Techniques .................................................................................. 17 2.4.5 Associated NWP products................................................................................................ 18 2.4.6 Brief Case Study.............................................................................................................. 19 2.5 LOW LEVEL JETS ................................................................................................................. 20 2.5.1 Description ..................................................................................................................... 20 2.5.2 Effects on Aircraft ........................................................................................................... 20 2.5.3 Diagnosis of Hazard Using Appropriate Imagery............................................................. 21 2.5.4 Empirical Forecasting Techniques..................................................................................22 2.5.5 Associated NWP products............................................................................................... 23 2.5.6 Brief Case Study.............................................................................................................. 23 2.6 WAKE TURBULENCE/WAKE VORTICES ................................................................................. 25 2.6.1 Description ..................................................................................................................... 25 2.6.2 Effects on Aircraft ........................................................................................................... 25 2.6.3 Diagnosis of Hazard Using Appropriate Imagery............................................................. 25 2.6.4 Empirical Forecasting Techniques .................................................................................. 26 2.6.5 Associated NWP Products ............................................................................................... 26 3 ICIN G ........................................................................................................................................ 27 3.1 AIRFRAME ICING .................................................................................................................. 27 3.1.1 Description ..................................................................................................................... 27 3.1.2 Effects on Aircraft ........................................................................................................... 29 3.1.3 Diagnosis of Hazard Using Appropriate Imagery............................................................. 30 3.1.4 Empirical Forecasting Techniques .................................................................................. 31 3.1.5 Icing Case Study ............................................................................................................. 35 3.2 CARBURETTOR AND ENGINE ICING ....................................................................................... 36 4. CUMULONIMBUS AND THUNDERSTORMS ...................................................................... 36 4.1 SEVERE TURBULENCE .......................................................................................................... 37 CONTENTS iv 4.2 SEVERE ICING ...................................................................................................................... 37 4.3 MICROBURSTS ..................................................................................................................... 37 4.4 THUNDERSTORMS AND LIGHTNING ....................................................................................... 37 4.4.1 Description ..................................................................................................................... 37 4.4.2 Effects on aircraft ........................................................................................................... 37 4.4.3 Diagnosis of Hazard Using Appropriate Imagery ............................................................ 38 4.4.4 Empirical Forecasting Techniques .................................................................................. 38 4.4.5 Associated NWP Products ............................................................................................... 39 4.5 HEAVY RAIN ........................................................................................................................ 39 4.5.1 Description ..................................................................................................................... 39 4.5.2 Effects on Aircraft ..........................................................................................................
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