DOCSLIB.ORG

Dot/Faa/Ct-88/8-1

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dot/Faa/Ct-88/8-1 .DTIC 0 :-i ~ •t AD-A238~ ~~II~lllll M039 lia JUL 0 1991 IDOFAA/CT-a8/8-1 Aircraft Icing Handbook FAA Technical Center Atlantic City International Airport Volume 1 of 3 N.J. 08405 .. 1 0 March 1991 This document is available to the U.S. public through the National Technical Information Service, Springfield, Virginia 22161 "FederalU.S. Department .""ation ofAdmi Transportation fl191-03901I i!nistration IIi i I 0 .i Ii _ _ _[------- - NOTICE This document is disseminated under the sponsorship of the U. S. Department of Transportation in the interest of information exchange. The United States Government assumes no liability for the contents or use thereof. The United States Government does not endorse products or wanuf• cturers. Trade or manufacturers' names appear herein solely because they are considered essential to the objective of this report. 0 IV• • Technical Report Documentation Pagle 1. Repart No. Government Access*un No. 3. Recip~ent's Catalog NM. DOT/FAA/CT-88/8- I 4. Title end Subtitle 5. R ep ote March 1991 Aircraft Icing Handbook - 6. Performing Organisation Code Volume i of 3 .. .. | ~~.vPrormingl Organisaetion Report No. 7. "v""',A. Heinrich, R. Ross, G. Zumwalt, J. Provorse, DOT/FAA/CT,88/8-l V. Padmanabhan, J. Thompson, J. Riley 9. Performing Orgoeniutian Name and Address 10. Work Unit No. (TRAIS) Gates Learjet Corporation 11. ContracG, No. 8220 W. Harry DTFA03_85_C_09QQ7 T Wichita, KS 67277 13. ype of Report and Period Cowered 12. Sponsoring Agency Name and Address Final Report Department of Transportation February 1985-March 1991 Federal Aviation Administration Technical Center 14. Ssaio Agency Code Atlantic City International Airport, NJ 08405 ACD 230 15. Supplementary Notes FAA Technical Monitor, E. E. Schlatter Flight Safety Research Branch ACD 230 16. Abs tract "-- The design and validation of adequate aircraft ice protection has evolved into a specialized and technically complex area where many engineering disciplines are involved; namely, aeronautical, electrical, mechanical, electronics, chemical simulations, mathematical modeliDg, airframe/engine systems design, atmospheric physics, and meteorology. Research advances in any one discipline have a direct effect on updating the procedural technology used in the design and validatiow of ice protection configurations, equipment, and systems. Periodically the Federal Aviation Administration (FAA) provides documentation to assist regulatory certification teams and industry design engineers in standardizing testing and validating procedures. Examples of such documentation are "Engineering Summary of Airframe Icing Technical Data," FAA Report No. ADS-4 dated December 1968, and 'TEngineering Summary of Powerplant Icing Technical Data," FAA Report No. RD-77-76 dated July 1977. Although most of the information contained in these reports is stiil valid, some is outdated, and more usable information is now available through recent research and experience. Therefore, this work was directed towards developing an updated and more comprehensive combined version of Report ADS-4 and RD-77-76 that includes reference material on ground and airborne icing facilities, simulation procedures, and analytical techniques. This document represents all types and classes of aircraft and is intended as a working tool for the designer and analyst of ice protection systems. (.• I17. Kay Wards II. Distribution Stotement Aircraft Icing Ice Protectioni Document is available to the U. S. public Atmospheric Icing t Icing Certificationj through National Technical Information Icing Measurements, •- De Icing - :J.41 Service, Springfield, Virginia. Anti-Icing lelicopterIT_ Icing, I* 5#rliy Clessil (o( this report) 20. Socuri#Y Classif. (af this sage) 21. No. of Polges 22. Price Unclassified. I Unclassified. :3 86 Form DOT F 1700.7 (8-72) Reproduction of completed page auborlzed 'I PREFACE This document, FAA Technical Report No. DOT/FAA/CT-88/8, produced in three volumes, is the final report of a program conducted by the Gates Learjet Corporation of Wichita, Kansas, to develop an updated comprehensive multi-volume engineering handbook on aircraft icing. he work effort was directed towards producing a combined version of Federal Aviation Administration (FAA) Technical Reports Number ADS-4 (airframe icing) and RD-77-76 (engine icing), which would include reference material on ground and airborne icing facilities, simulation procedures, and analytical techniques and represent all types and classes of aircraft. The program was sponsored by the FAA Aircraft Icing Program, Flight Safety Research Branch, at the FAA Technical Center, Atlantic City International Airport, New Jersey. Mr. Ernest Schlatter, Research Meteorologist, was the Technical Monitor for the FAA Technical Center. Dr. James T. Riley and Mr. Charles 0. Masters of the FAA's Aircraft Icing Program were instrumental in the completion of this document following the retirement of Mr. Schlatter. Work was performed under the coordination of Mr. A.M. Heinrich, Project Director. Technical support was provided by Mr. Rihrd FRoss of Ross Aviation Associates, Sedgwick, Kansas; Dr. Glen Zumwalt of Wichita State University, Wichita, Kansas; Mi. John Provorse of Cedar Hill Industries, El Dorado, Kansas; and Dr. VYiwa Pad manabhan of the Gates Learjet Corporation. Additional subcontractor contribution to the handbook was provided by the following companies * and academic institutions: Aeromet, Inc., Tulsa, Oklahoma A; Beech Aircraft Corporation, Wichita, Kansas Boeing Vertol Company, Ridley Park, Pennsylvania 0.!' ?,. Douglas Aircraft Company, Long Beach, California '"' Li Ideal Research, Inc., Rockville, Maryland - . Kohiman Aviation, Lawrence, Kansas Ohio State University, Columbus, Ohio - -t --- .I t-r 1-- I.Q,,-t /e .. Pratt and Whitney Aircraft Group, East Hartford, Connecticut Av-iva1.l / Rosemount Inc., Burnsville, Minnesota Didst Speal Rohr Aircraft Industries, Inc., Chula Vista, California Sikorsky Aircraft Company, Stratford, Connecticut RA Sverdrup Technology, Inc., Tullahoma, Tennessee Wichita State University, Wichita, Kansas An additional contractor contribution to the handbook was provided by Mr. James Thompson of Thompson Enterprises, Arlington, Virginia. Appreciation is gratefully extended for the assistance and material provided by personnel of the B.F. Goodrich Company, Akron, Ohio; Fluidyne Engineering Corporation, Minneapolis, Minnesota; National Research Council (NRC), Ottawa, Canada; NASA Lewis Research Center, - iii "fi" Cleveland, Ohio; U.S. Army Cold Regions Research and Engineering Laboratory (CRREL), Hanover, New Hampshire; Mount Washington Observatory, Gorham, New Hampshire; Leigh Instrument Company, Ontario, Canada; and McKinley Climatic Laboratory, Eglin AFB, Florida. Technical review was provided by the FAA's Aircraft Icing National Resource Specialist in Washington, D.C.; personnel in the four FAA Aircraft Certification Directorates (Boston, Massachusetts; Ft. Woi in, Texas; Kansas City, Missouri; and Seattle, Washington); personnel at the NASA Lewis Research Center, Cleveland, Ohio, the U.S. Naval Research Laboratory, Washington, D.C.; and members of the Society of Automotive Engineers Aircraft Icing Technology Subcommittee AC-9C. iv 0 IN-FRODIUCTION The formailon of ice on aircraft has been a concern since the early days of aviation. There are three basic forns et' ice accumulation on aircraft: rime ice, glaze (clear) ice, and frost. Mixtures of rime and glaze ice are common. Ice on the airframe decreases lift and increases weight, drag, and Ai~ stalling speed. in addition, the accumulation of ice on the exterior moveable surfaces affects the control of the aircraft. If ice begins to formu on the blades of a propeller or helicopter rotor, its propulsion efficiency is decreased and further power is demanded of the engine to maintain flight. The overall effect on the aircraft is loss of aerodynamic efficiency, engine power, proper control I surface operation, brake and landing gear operation, outside vision, proper flight instrument t j indications, and, in the extreme, loss olý radio communication due to antenna shielding or damage. Certain area3 of the aircraft's outer surfaces, sometimes even critical surfaces, may be damaged when impacted by shed ice. Engine ingestion of the shed ice and subsequent damage or engine failure is another cause for concern. Early aircraft were often forced down due to ice accretion on wings, * empennage, and propellers. If the aircraft was unuamaged, the ice was cleared and the aircraft continued on its flight. Eventually, pneumnaltic -boot de-icers were developed followed by fluid, hot air and electric ice p.rotection systems. Both the number of instrument rated pilots and the number 2 ~of rotorcraft and general aviation aircraft equipped for flight into icing environmients have increased dramatically in recent years. Transport category and corporate aircraft are continually advancing in aerodynamic designs and striving for more fuel efficient engines and propellers. As the requirements change, so do the requirements for modifying contemporary ice protectioc systems. Therefore, to improve and optimize ice protection capabilities, there is a need for research and development of de-icing/ anti-icing systems and analysis procedures. Present research is concentrating in the areas of electro- impulse, improved pneumatics, electro-thermal, fluid freezing point depressant, mnicrowave, and icephobic ice protection systems. The design and successful certification of these systems depend
Load more

Recommended publications
  • In-Cloud Icing and Supercooled Cloud Microphysics: from Reanalysis to Mesoscale Modeling
    UNIVERSITY OF QUEBEC AT CHICOUTIMI MANUSCRIPT-BASED THESIS PRESENTED TO UNIVERSITY OF QUEBEC AT CHICOUTIMI IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF PHILOSOPHIAE DOCTOR Ph.D. IN EARTH AND ATMOSPHERIC SCIENCES OFFERED AT UNIVERSITY OF QUEBEC AT MONTREAL UNDER A MEMORANDUM OF UNDERSTANDING WITH THE UNIVERSITY OF QUEBEC AT CHICOUTIMI BY FAYÇAL LAMRAOUI IN-CLOUD ICING AND SUPERCOOLED CLOUD MICROPHYSICS: FROM REANALYSIS TO MESOSCALE MODELING NOVEMBER 2014 © Fayçal Lamraoui, 2014 The ice storm - January 1998 Oil on canvas painting – Artist: A. Poirier In the distance, the Montérégie, viewed from Mont-Royal (Montreal, Quebec, Canada) (Courtesy of the community Ste-Croix, Saint-Laurent) iii ABSTRACT In-cloud icing is continually associated with potential hazardous meteorological conditions at higher altitudes in the troposphere across the world and near surface over mountainous and cold climate regions. This PhD thesis aims to scrutinize the horizontal and vertical characteristics of near-surface in-cloud icing events, the associated cloud microphysics, develop and demonstrate an innovative method to determine the climatology of icing events at high resolution. In reference to ice accretion, the quantification of icing events is based on the cylinder model. With the use of North American Regional Reanalysis, a preliminary mapping of the icing severity index spanning a 32-year time period is introduced and in that way the freezing precipitation during the ice storm of January 1998 is quantified and compared to observations. Also, case studies over Mount- Bélair and Bagotville are investigated. The assessment of icing events obtained from NARR demonstrates agreements with observation over simple terrains and disparities over complex terrains, due to the coarse resolution of the reanalysis.
    [Show full text]
  • FAA Advisory Circular AC 91-74B
    U.S. Department Advisory of Transportation Federal Aviation Administration Circular Subject: Pilot Guide: Flight in Icing Conditions Date:10/8/15 AC No: 91-74B Initiated by: AFS-800 Change: This advisory circular (AC) contains updated and additional information for the pilots of airplanes under Title 14 of the Code of Federal Regulations (14 CFR) parts 91, 121, 125, and 135. The purpose of this AC is to provide pilots with a convenient reference guide on the principal factors related to flight in icing conditions and the location of additional information in related publications. As a result of these updates and consolidating of information, AC 91-74A, Pilot Guide: Flight in Icing Conditions, dated December 31, 2007, and AC 91-51A, Effect of Icing on Aircraft Control and Airplane Deice and Anti-Ice Systems, dated July 19, 1996, are cancelled. This AC does not authorize deviations from established company procedures or regulatory requirements. John Barbagallo Deputy Director, Flight Standards Service 10/8/15 AC 91-74B CONTENTS Paragraph Page CHAPTER 1. INTRODUCTION 1-1. Purpose ..............................................................................................................................1 1-2. Cancellation ......................................................................................................................1 1-3. Definitions.........................................................................................................................1 1-4. Discussion .........................................................................................................................6
    [Show full text]
  • Thermometer 1 Thermometer
    Thermometer 1 Thermometer Developed during the 16th and 17th centuries, a thermometer (from the Greek θερμός (thermo) meaning "warm" and meter, "to measure") is a device that measures temperature or temperature gradient using a variety of different principles.[1] A thermometer has two important elements: the temperature sensor (e.g. the bulb on a mercury thermometer) in which some physical change occurs with temperature, plus some means of converting this physical change into a numerical value (e.g. the scale on a mercury thermometer). A clinical mercury-in-glass thermometer There are many types of thermometer and many uses for thermometers, as detailed below in sections of this article. Temperature While an individual thermometer is able to measure degrees of hotness, the readings on two thermometers cannot be compared unless they conform to an agreed scale. There is today an absolute thermodynamic temperature scale. Internationally agreed temperature scales are designed to approximate this closely, based on fixed points and interpolating thermometers. The most recent official temperature scale is the International Temperature Scale of 1990. It extends from 0.65 K (−272.5 °C; −458.5 °F) to approximately 1358 K (1085 °C; 1985 °F). Thermometer Thermometer 2 Development Various authors have credited the invention of the thermometer to Cornelius Drebbel, Robert Fludd, Galileo Galilei or Santorio Santorio. The thermometer was not a single invention, however, but a development. Philo of Byzantium and Hero of Alexandria knew of the principle that certain substances, notably air, expand and contract and described a demonstration in which a closed tube partially filled with air had its end in a container of water.[2] The expansion and contraction of the air caused the position of the water/air interface to move along the tube.
    [Show full text]
  • Guidelines for Meteorological Icing Models, Statistical Methods and Topographical Effects
    291 GUIDELINES FOR METEOROLOGICAL ICING MODELS, STATISTICAL METHODS AND TOPOGRAPHICAL EFFECTS Working Group B2.16 Task Force 03 April 2006 GUIDELINES FOR METEOROLOGICAL ICING MODELS, STATISTICAL METHODS AND TOPOGRAPHICAL EFFECTS Task Force B2.16.03 Task Force Members: André Leblond – Canada (TF Leader) Svein M. Fikke – Norway (WG Convenor) Brian Wareing – United Kingdom (WG Secretary) Sergey Chereshnyuk – Russia Árni Jón Elíasson – Iceland Masoud Farzaneh – Canada Angel Gallego – Spain Asim Haldar – Canada Claude Hardy – Canada Henry Hawes – Australia Magdi Ishac – Canada Samy Krishnasamy – Canada Marc Le-Du – France Yukichi Sakamoto – Japan Konstantin Savadjiev – Canada Vladimir Shkaptsov – Russia Naohiko Sudo – Japan Sergey Turbin – Ukraine Other Working Group Members: Anand P. Goel – Canada Franc Jakl – Slovenia Leon Kempner – Canada Ruy Carlos Ramos de Menezes – Brasil Tihomir Popovic – Serbia Jan Rogier – Belgium Dario Ronzio – Italy Tapani Seppa – USA Noriyoshi Sugawara – Japan Copyright © 2006 “Ownership of a CIGRE publication, whether in paper form or on electronic support only infers right of use for personal purposes. Are prohibited, except if explicitly agreed by CIGRE, total or partial reproduction of the publication for use other than personal and transfer to a third party; hence circulation on any intranet or other company network is forbidden”. Disclaimer notice “CIGRE gives no warranty or assurance about the contents of this publication, nor does it accept any responsibility, as to the accuracy or exhaustiveness of the
    [Show full text]
  • Evaluation of Ice Detection Systems for Wind Turbines Final Report
    Weather Forecasts Renewable Energies Air and Climate Environmental IT Genossenschaft METEOTEST Fabrikstrasse 14, CH-3012 Bern Tel. +41 (0)31 307 26 26 Fax +41 (0)31 307 26 10 [email protected], www.meteotest.ch Bern, February 16, 2016 Evaluation of ice detection systems for wind turbines Final report VGB Research Project No. 392 report_v8_final.docx/rc METEOTEST 2 Disclaimer All information presented in this report is solely based on documents provided by the manufacturers of the ice detection systems as well as publicly available reports, papers and presentations. No data analysis has been carried out by Meteotest for this report. Especially the information on the accuracy of the systems has not been checked or validated by Meteotest or by TÜV NORD. Acknowledgements The research project "Evaluation of ice detection systems for wind turbines" was funded by VGB PowerTech e.V., which is kindly acknowledged. The project was initiated and supervised by the VGB Technical Committee "Wind Energy." The au- thors would like to thank the companies EnBW, Enercity (Stadtwerke Hannover), Energiewerkstatt, ESB Renewables, EVN Naturkraft, Fortech, GDF Suez Canada (now Engie) , GDF Suez Europe (now Engie), RheinEnergie, Vattenfall and WSB Service Deutschland for their active participation in the survey among wind-turbine operators conducted within the project. Finally the authors wish to thank all manu- facturers of ice detection systems for their active and transparent collaboration in the project. Version Date Document Project Number 1 16.02.2016 Final Report 15_025 Editing Name Date Created by René Cattin, Dr. Ulla Heikkilä 22.12.2015 Controlled by Dr. Ulla Heikkilä 23.12.2015 Approved by Dr.
    [Show full text]
  • Meteorological and Environmental Inputs to Aviation Systems
    https://ntrs.nasa.gov/search.jsp?R=19880015721 2020-03-20T07:07:10+00:00Z NASA Conference Publication 2498 c Meteorological and Environmental Inputs to Aviation Systems Proceedings of a workshop held at the University of Tennessee Space Institute in Tullahoma, Tennessee March 12-14, 1985 NASA Conference Publication 2498 Meteorological and Environmental Inputs to Aviation Systems . Edited by Dennis W. Camp and Walter Frost University of Tennessee Space Institute Tullahoma, Tennessee Proceedings of a workshop jointly sponsored by the National Aeronautics and Space Administration, .National Oceanic and Atmospheric Administration (Department of Commerce), Federal Aviation Administration (Department of Transportation), Department of Defense, and Office of the Federal Coordinator for Meteorology, and held at the University of Tennessee Space Institute in Tullahoma, Tennessee March 12-14, 1985 National Aeronautics and Space Administration Scientific and Technical Information Division PREFACE The first in a series of annual workshops addressing meteorological inputs to aviation systems was held on March 17-19, 1977, at the University of Tennessee Space Institute in Tullahoma, Tennessee. The workshops were initially sponsored by NASA, NOAA and the FAA, and were later joined in sponsorship by DOD and the Office of the Federal Coordinator. They have provided a forum for open discussion of weather and environmental concerns between the research, operations and user organizations within the aviation community. Following the past few workshops, several individuals have voiced concern over the benefit of what has become a continuing workshop with in many instances the same continuing recommendations. To assess the value of a continuing workshop one must look beyond a simple comparison of recommendations made year to year.
    [Show full text]
  • Analysis of Ice-To-Liquid Ratios During Freezing Rain and the Development of an Ice Accumulation Model
    VOLUME 31 WEATHER AND FORECASTING AUGUST 2016 Analysis of Ice-to-Liquid Ratios during Freezing Rain and the Development of an Ice Accumulation Model KRISTOPHER J. SANDERS AND BRIAN L. BARJENBRUCH NOAA/National Weather Service, Topeka, Kansas (Manuscript received 12 September 2015, in final form 17 March 2016) ABSTRACT Substantial freezing rain or drizzle occurs in about 24% of winter weather events in the continental United States. Proper preparation for these freezing rain events requires accurate forecasts of ice accumulation on various surfaces. The Automated Surface Observing System (ASOS) has become the primary surface weather observation system in the United States, and more than 650 ASOS sites have implemented an icing sensor as of March 2015. ASOS observations that included ice accumulation were examined from January 2013 through February 2015. The data chosen for this study consist of 60-min periods of continuous freezing rain with 2 2 precipitation rates $ 0.5 mm h 1 (0.02 in. h 1) and greater than a trace of ice accumulation, yielding a dataset of 1255 h of observations. Ice:liquid ratios (ILRs) were calculated for each 60-min period and analyzed with 60-min mean values of temperature, wet-bulb temperature, wind speed, and precipitation rate. The median ILR for elevated horizontal (radial) ice accumulation was 0.72:1 (0.28:1), with a 25th percentile of 0.50:1 (0.20:1) and a 75th percentile of 1.0:1 (0.40:1). Strong relationships were identified between ILR and pre- cipitation rate, wind speed, and wet-bulb temperature. The results were used to develop a multivariable Freezing Rain Accumulation Model (FRAM) for use in predicting ice accumulation incorporating these commonly forecast variables as input.
    [Show full text]
  • Federal Research and Technology for Aviation
    Federal Research and Technology for Aviation September 1994 OTA-ETI-610 NTIS order #PB95-109195 GPO stock #052-003-01391-6 Recommended Citation: U.S. Congress, Office of Technology Assessment, Federal Research and Technology for Aviation, OTA–ETI-61O (Washington, DC: U.S. Government Printing Office, September 1994). For sale by the US. Government Printing Office Superintendent of Documenta, Mail Stop: SSOP, Washington, DC 20402-9328 Foreword ithin the United States, only the federal government has the re- sources to support large-scale, applied research and develop- ment programs for aviation safety and infrastructure. Federally sponsored aviation research has received considerable congres- sionalw attention in the last decade due to the need to modernize and expand the U.S. airspace system, address aircraft safety and environmental issues, and respond to terrorism threats against air travelers. The House Committee on Science, Space, and Technology and its Subcommittee on Competitive- ness and Technology (now the Subcommittee on Technology, Environment and Aviation) asked the Office of Technolog y Assessment to take a compre- hensive look at the federal R&D that underpins the Federal Aviation Ad- ministration’s technology and regulatory development programs. Long- term research efforts and airline economics were special concerns. The study was also endorsed by the House Subcommittee on Aviation of the Committee on Public Works and Transportation, and the House Subcom- mittee on Government Activities and Transportation of the Committee on Government Operations. This report focuses on research and technology policy issues for aviation operations: safety, security, environmental protection, and the air traffic system. Achievements in science and technology have helped make the U.S.
    [Show full text]
  • Modern Meteorology and Atmospheric Icing
    IWAIS XI, Montréal, June 2005 Modern Meteorology and Atmospheric Icing Svein M. Fikke Meteorological consultant – overhead lines, Lindeveien 1, 1470 Lørenskog, Norway [email protected] Abstract—Although the water cycle in the atmosphere is still not according to local experiences. Now we all agree to described well enough to provide reliable input parameters for encompass all phenomena that cause accretions of water in its the liquid water content of the air or precipitation rate, fine-scale frozen stage on any type of object into the term “icing” [1], atmospheric models can now describe wind speed, wind direction, air temperature and vertical stability taking [2]. We differentiate icing according to the process during topographical details into account with a horizontal scale of 100 which the accretion is formed. m or less. This means that these models can provide much more “Atmospheric icing” is therefore now a global term for: detailed information than any observation network can do - in-cloud icing, concerning both weather and icing data. Examples are shown on - precipitation icing, and the application of such models for detailed studies on power lines. - hoar frost. A comprehensive scheme for combining models for weather dependent impacts on overhead lines and weather forecasting In-cloud icing is often also denoted as (soft and hard) rime models is suggested. icing. Precipitation icing may result in I. INTRODUCTION - freezing rain, TMOSPHERIC icing has been on the agenda for - wet snow, and A international collaboration since the very first IWAIS - dry snow. (although it was not called so then) in Hanover, New Hoar frost is the result of a phase transition direct from Hampshire, in 1982.
    [Show full text]
  • Ice Storm Maps I
    Trees & Ice Storms Series WSFNR15-3 February 2015 Formation of Freezing Rain Events by Dr. Kim D. Coder, Professor of Tree Biology & Health Care Warnell School of Forestry & Natural Resources, University of Georgia Ice storms can be devastating to trees and surrounding structures. An ice storm is defined by the US-National Weather Service as any freezing rain event where ice accumulation is at least 0.25 inches. Catastrophic tree failures from added ice weight, drag coefficient increases, and increased stiffness against the wind all conspire to damage or topple trees. A brief review of how ice storms form and spread is needed to help tree health care providers understand potential tree damage. Precipitation Definitions Ice storm is a generic name for a precipitation and wind event where freezing rain is a significant component. Officially, “freezing rain” is defined as liquid water drops with diameters greater than 0.5mm (~0.02 inch) which freeze upon impact with the ground or other structures, like trees, and gener- ate a glaze layer of ice. Surface objects must be at or below freezing, and the rain must be supercooled before impact. (Gay & Davis 1993) (Stuart & Isaac 1999) A “glaze” is defined as a clear layer of ice formed by supercooled water freezing on the surface of an object. (Lemon 1961) “Freezing drizzle” are droplets less than 0.5mm (~0.02 inch) in diameter which freeze on contact forming an ice glaze. “Freezing precipitation” is a generic term which includes freezing rain and freez- ing drizzle. (Gay & Davis 1993) (Stuart & Isaac 1999) Falling ice pellets are officially termed “sleet.” Unofficially, many people use the term sleet to represent a mixture of ice and liquid particles (mixed snow crystals, ice pellets, and rain).
    [Show full text]
  • Federal Research and Technology for Aviation
    — — Research and Technology Issues 4 n December 1903, the Wright brothers conducted the first controlled, powered flight of an airplane near Kitty Hawk, North Carolina. This event heralded a new age of adventure I and service, and decades of aviation research and develop- ment (R&D) have since fostered the growth of an extensive in- dustry. An example of the degree of change witnessed in aviation is that a Boeing 747 aircraft fuselage could contain not only the Wright brothers’ plane but its entire fright path. More important than the dramatic growth in aircraft size is that federal research and technology efforts have helped to make aircraft operation saf- er, more economical, and quieter. Innovations in technology also have provided for effective and efficient methods of managing air traffic in congested airspace and on crowded airport surfaces; reliable, rapid means of commu- nication over vast distances; advanced warning of hazardous weather; improved air- and crashworthiness; reduced security threats; and enhanced training methods for personnel throughout the industry. However, a broad array of basic science, risk assess- ment, technology development, and test and evaluation efforts is needed to improve existing technologies and add new functions to the air transportation system, strengthen analytic capabilities in order to identify and clarify emerging issues, and develop technology or procedural options to unresolved problems. As both the regulatory agency for civil aviation and the opera- tor of the nation’s air traffic control system, the Federal Aviation ‘ Rc]gcr E. 1311stein. Orders t{ Magrutude: A Hi.\tor? of the ,NACA and iVASA, 19/5-1990, NASA SP-44M (Wra$hington, DC: National Aeronautic and Space AcImin- I 117 istration, 1 989), p.
    [Show full text]
  • Cloud Characterization in CIRA Icing Wind Tunnel
    Università Degli studi di Napoli “Federico II” TESI DI DOTTORATO IN INGEGNERIA AEROSPAZIALE, NAVALE E DELLA QUALITÀ CICLO XIX Cloud Characterization in CIRA Icing Wind Tunnel Relatori Ch.mi: Matteo Bellucci Prof. Ing. G. M. Carlomagno Centro Italiano Ricerche Aerospaziali Prof. Ing. T. Astarita DETEC, Facoltà di Ingegneria Page 1 of 243 INDEX INTRODUCTION .................................................................................................................6 CHAPTER 1 ........................................................................................................................9 WHY AIRCRAFT ICING IS DANGEROUS .........................................................................9 1.1 ICING THREAT......................................................................................................................9 1.2 KINDS OF ICE .......................................................................................................................9 1.2.1 Clear (or Glaze) Ice....................................................................................................10 1.2.2 Rime Ice .....................................................................................................................11 1.2.3 Mixed Ice....................................................................................................................12 1.3 WHY THEY FALL: EFFECT OF ICE ACCRETION ON AIRCRAFT FLIGHT DYNAMICS...13 1.3.1 Performance Degradation.........................................................................................13
    [Show full text]