SURFACE WINDSHEAR ALERT SYSTEM, PART 2 - FIELD-TESTS

Field tests of the surface windshear alert system (SURFWAS) prototype described in a companion paper were conducted at the U.S. Air Force Ac ademy Airfield. An array of seven remote stations on 6.1- and 9.2-m me teorological towers was erected alongside runway 16L (34R), covering a distance of about 2 n mile. Wind data were recorded for 11 days from Aug. 12-22, 1996, during which several windy episodes, associated most ly with thunderstorms and one cold front, passed through the airfield. Two of the episodes exhibited the patterns of dry and wet microbursts , respectively, which were consistent with the forecast at the U.S. Ai r Force Academy Weather Flight. The wind data measured with the SURFWA S and the airfield wind sensors agreed reasonably well. During the two episodes, the maximum windshears exceeded the alert threshold while t he windshear patterns satisfied the alarm criteria, triggering the mic roburst alert alarm. The SURFWAS' capability of detecting microbursts near ground level to provide timely warning, via terminal display and direct broadcast, to air traffic controllers and pilots was successful ly established. The success is attributed to the high runway-oriented resolution of the remote anemometer station array for wind measurement s and the timely update of the wind information at the master station.