10.13
Operational Experience with TDWR/LLWAS-NE Integration at the Dallas, TX International Airport (DFW)
David W. Miller, MIT Lincoln Lab., Dallas, TX; and B. E. Crowe and J. D. Shaw
The Integrated Terminal Weather System (ITWS) has a set of wind shear detection algorithms that operate on data from the Terminal Doppler Weather Radar (TDWR) to generate airport-based wind shear alerts. At airports that have a Network Expansion of the Low-Level Wind Shear Advisory System (LLWAS-NE), ITWS will integrate the LLWAS-NE alerts with those generated by the TDWR-based algorithms to provide integrated wind shear alerts.
The Dallas / Fort Worth Airport (DFW) is one of four demonstration system sites for the ITWS. The LLWAS-NE generated alerts were integrated into the DFW ITWS test suite in order to provide extended testing of the integration logic. DFW is unique in that the airport is large with an extensive network of LLWAS sensors and the area experiences a wide variety of weather conditions including gusty winds. In June of 2001, the DFW LLWAS-NE system was upgraded to convert existing mechanical anemometers to sonic anemometers.
In this study, we examine the behavior of the integrated wind shear detection system with particular emphasis on situations where the TDWR-based detection performance at DFW was poor. Specific TDWR detection problems observed include: wind shear events over the airport that were aligned along a radial to the TDWR, surface divergences following gust fronts or embedded in gravity waves that occurred outside of precipitation areas, severe signal attenuation when heavy precipitation falls over the TDWR radar site, and excessive TDWR clutter-residue editing over the airport. In spite of performance limitations of the LLWAS-NE (e.g., those resulting from non-optimal sensor placement), the inclusion of its alerts has enabled the DFW ITWS to provide appropriate and timely wind shear alerts in all of the above cases.
* This work was sponsored by the Federal Aviation Administration under Air Force Contract No. F19628-00-C-0002. The views expressed are those of the authors and do not reflect the official policy or position of the U.S. Government. Opinions, interpretations, conclusions, and recommendations are those of the authors and are not necessarily endorsed by the US Government.
Session 10, Turbulence and Wind Sheer
Thursday, 16 May 2002, 8:00 AM-11:45 AM
Previous paper