Accession Number : ADA307822

Title :   Representative Values of Icing-Related Variables Aloft in Freezing Rain and Freezing Drizzle.

Descriptive Note : Technical note,

Corporate Author : FEDERAL AVIATION ADMINISTRATION TECHNICAL CENTER ATLANTIC CITY NJ

Personal Author(s) : Jeck, Richard K.

PDF Url : ADA307822

Report Date : MAR 1996

Pagination or Media Count : 54

Abstract : Radiosonde and surface observations in freezing rain (ZR) and freezing drizzle (ZL), and a limited number of aircraft measurements in ZR, have been examined for information on the magnitude and altitude dependence of meteorological variables associated with aircraft icing in these conditions. The variables include temperature aloft, humidity (clouds), and windshear from the radiosondes; surface temperatures, ceiling heights, precipitation type and amount from the surface observations; and temperature, dropsize, rainwater concentration, and icing rate from the instrumented aircraft. These and other data are used here to arrive at tentative maximum and representative values of these variables. To overcome the inadequacy of median volume diameter (MVD) as a measure of dropsize for these large droplet conditions, a convention for reporting the ZR or ZL water concentration over a few coarse dropsize intervals is proposed.

Descriptors :   *ICE FORMATION, *RAIN, *AVIATION ACCIDENTS, AIRCRAFT, AIRCRAFT MAINTENANCE, AIR FLOW, ATMOSPHERIC TEMPERATURE, METEOROLOGICAL DATA, WEATHER FORECASTING, TEMPERATURE GRADIENTS, FREEZING, RAINDROPS, FUSELAGES, WIND SHEAR, TAKEOFF, CIVIL AVIATION, RADIOSONDES, AVIATION SAFETY, SURFACE TEMPERATURE, CLOUD COVER, AIRCRAFT LANDINGS, HUMIDITY, ICE FORECASTING, ICE PREVENTION.

Subject Categories : Meteorology
      Snow, Ice and Permafrost
      Commercial and General Aviation

Distribution Statement : APPROVED FOR PUBLIC RELEASE