Snow Effects of Image Glide Path Systems: Winter of 1971-1972

摘要

Results of tests to determine the effect of snow on image glide path systems are presented. Effects on three systems, capture effect, null reference, and sideband reference are discussed in terms of change in the far-field signal characteristics. Data includes; far-field signals such as received in the aircraft, conventional near-field monitor signals, analog, integral-monitor signals, and trends of the signals as a function of environmental condition. The primary conclusions are that new snow depths less than eight inches do not generally cause a change in the path but a change in the snow surface condition such as during a thaw tends to make the path move upward as if the ground plane were simply elevated. The conclusions agree with theoretical predictions. (Author)