Publications

The ASR-9 Wind Shear Processor (WSP) is intended as an economical alternative for those airports that have not been slated to receive a Terminal Doppler Weather Radar (TDWR) but have, or will be receiving, an ASR-9 radar. Lincoln Laboratory has developed a prototype ASR-9 WSP system which has been demonstrated during the summer months of the past three year in Orlando, Florida. During the operational test period, microburst and gust front warnings, as well as storm motion indications, were provided to the Air Traffic Control in real time. The ASR-9 Microburst Detection Algorithm (AMDA) is based on the earlier TDWR Microburst Detection Algorithm but has been substantially modified to match better the particular strengths and weaknesses of the ASR-9 rapid-scanning fan-beam radar. The most significant additions included a capability to detect overhead microbursts, a reflectivity processing step used to help detect velocity signatures that have been biased by overhanging precipitation, and a modification to some of the shear segment grouping and thresholding parameters to accommodate better the typical on-air siting of the ASR-9. In addition, the AMDA has been designed to be as efficient as possible to allow it to run at the radar's 4.8 seconds/scan antennas rotation rate on a single-board computer. A detailed description of AMDA, as well as the performance evaluation strategy and results, are presented in this report.

Lincoln Laboratory, under sponsorship from the Federal Aviation Administration (FAA), is conducting a program to evaluate the capability of the newest Airport Surveillance Radars (ASR-9) to detect hazardous weather phenomena -- in particular, low-altitude wind shear created by thunderstorm-generated microbursts and gust fronts. The ASR-9 could provide coverage at airports not slated for a dedicated Terminal Doppler Weather Radar (TDWR) and could augment the TDWR at high-priority (high traffic volume, severe weather) facilities by providing a more rapid update of wind shear products, a better viewing angle for some runways, and redundancy in the event of a TDWR failure. An operational evaluation of a testbed ASR Wind Shear Processor (ASR-WSP) was conducted at the Orlando International Airport in Orlando, FL during August and September 1990. The ASR-WSP operational system issued five distinct products to Air Traffic Control: microburst detections, gust front detections, gust front movement predictions, precipitation reflectivity and storm motion. This document describes the operational system, the operational products, and the algorithms employed. An assessment of system performance is provided as one step in evaluating the operational utility of the ASR-WSP.