Accession Number : AD0690461

Title :   EARTH COVER AND CONTOUR EFFECTS ON IMAGE GLIDE PATHS. PHASE III.

Descriptive Note : Final rept.,

Corporate Author : OHIO UNIV ATHENS DEPT OF ELECTRICAL ENGINEERING

Personal Author(s) : McFarland,Richard H. ; Gorman,James T. ; Gilchrist,Thomas ; Rice,James ; Wistendahl,Warren

Report Date : SEP 1968

Pagination or Media Count : 344

Abstract : Confirming evidence is presented that the UHF image glide-path angle as seen by the monitor can move either up or down, and that with wet snow covers the far-field path can exceed tolerances. This is the first time simultaneous records have been made of near and far-field glide path angles. Correlation between far-field path change and near-field monitor indication has been calculated and measured. The mathematical model used to predict the effects of a ground plane snow cover has been extended to include cases where multilayers of snow exist. Realizable accuracies are within acceptable tolerances but practical application is presently limited by lack of continuous information on the value of the dielectric constant of the snow. Accurate predictions of glide path roughness due to terrain are made using a new mathematical model. In order to investigate the three dimensional structure of the glide path, path shapes at various angles were computed for Pittsburgh, Pennsylvania; Charleston, West Virginia; Cincinnati, Ohio; and Athens, Ohio, sites. Results of these data are compared with flight data obtained using a radio telemetering theodolite. (Author)

Descriptors :   (*INSTRUMENT LANDINGS, GLIDE PATH SYSTEMS), (*GLIDE PATH SYSTEMS, RELIABILITY), TERRAIN, FLIGHT PATHS, MATHEMATICAL MODELS, SNOW, RADIO NAVIGATION, RADIO SIGNALS, SCATTERING, PLANTS(BOTANY), ATTENUATION, MONITORS, COMPUTER PROGRAMS, PENNSYLVANIA, WEST VIRGINIA, OHIO

Subject Categories : Air Navigation and Guidance

Distribution Statement : APPROVED FOR PUBLIC RELEASE