The Dulles Airport Acoustic-Microwave Radar Wind and Wind Shear Measuring System

Abstract

Wind shear has been recognized as a major aviation hazard in the airport environment. A dual, acoustic Dopplermicrowave Doppler radar system has been installed at Dulles International Airport near Washington, D.C., to measure the vertical profile of wind from the surface to 510 m in 30 m height increments. The acoustic system gathers data under clear-air conditions, and the microwave radar takes over automatically when precipitation is present. System performance is being assessed by comparing its output with National Weather Service radiosondes and with balloonborne anemometers and by intercomparing the acoustic-and microwave-measured winds under light precipitation conditions. The dual-sensor system has been operating for several months, registering the passage of fronts, some with potentially hazardous wind shears.

Aeronautical Meteorology: Progress and Challenges—Today and Tomorrow

“…The wake vortex system currently under test at O'Hare International measures the winds at two levels from six locations with the objective of defining the wind fields so as to determine the separation standards to be used in operating from the runways (Hallock et al, 1976). A ground-based system using Doppler technique on data from an acoustic sensor and a microwave radar to determine the vertical structure of the wind field up to 1500 ft above an airport is under test at Dulles International Airport (Hardesty et al, 1977). This wind information is processed so as to provide the controller (and pilot) with information on the altitude and amount of significant vertical wind shear.…”

Interpretation of Acousting Sounding Records with Meterological Parameters and Ventilation Coefficient Over Delhi

“…Major technique includes direct measurement such as Tethered balloon, Radiosonde and Remote sensing techniques such as Lidar, Doppler Radar and Sodar [4,6,14,15]. Among all these, SODAR is a valuable and significant instrument for ABL height determination upto 3 km with real time and good space resolution capability [16][17][18][19]. Since the last 40-years SODAR technique has been developed to a very useful tool for ABL investigation.…”

Πειραματικη Μελετη Του Ατμοσφαιρικου Οριακου Στρωματος Πανω Απο Ενα Οξυ Βουνο

“…Από την εξίσωση αυτή παρατηρείται ότι η λαμβανόμενη τάση Vr από ένα μονοστατικό radar είναι συνάρτηση της απόστασης R για δοθείσες τιμές 4π των Ρ 0 ( r), Gr , σ(π), 0,τ,Ι_ και k. Ο όρος -ρ-Β βρίσκεται ίσος με 8.07 για οποιοδήποτε μονοστατικό radar με στενή δέσμη. ' Ετσι, η εξίσωση (1.27) γίνεται: Πρόσφατες έρευνες (Beran 1971, Beran and .Clifford 1972, Asimakopoulos and Cole 1977 οδήγησαν στην ανάπτυξη ακουστικών Doppler συστημάτων, που έχουν βρει πολλές εφαρμογές, όπως σε μετρήσεις ανέμου σε αεροδρόμια (Hardesty et al 1977). Τα ακουστικά Doppler συστή ματα αναπτύχθηκαν γρήγορα από μιά διάταξη μιας κεραίας, που μετρούσε μόνο την κάθετη συνιστώσα του ανέμου, σε πολλαπλά συστήματα εκπομπής--λήψης, που δίνουν την κατακόρυφη κατανομή όλων των συνιστωσών ιου ανέ μου.…”