Windshear detection and reporting capabilities are currently provided at 110 airports in the United States by aging Low Level Windshear Alert (LLWAS) systems, designated as LLWAS–2 and LLWAS–3 type systems. As part of the Federal Aviation Administration (FAA) Integrated Windshear Plan strategy, Terminal Doppler Weather Radar (TDWR) and the Airport Surveillance-Radar Weather Systems Processor (WSP) will be deployed and utilized for windshear detection and reporting, but stand alone LLWAS–2 systems will remain as the sole source of windshear detection and reporting at 40 airports. To mitigate long term system operations, maintenance, and supportability concerns with these existing systems, sustaining engineering efforts have been initiated through the LLWAS–RS program. The LLWAS–RS program consists of replacing the entire systems at the 40 operational LLWAS–2 sites. The LLWAS-RS Program has an option to replace the existing LLWAS-3 sites with functionaly-equivalent LLWAS-RS equipment. The goal of the sustainment element of the program is to upgrade LLWAS hardware and software to achieve one logistically supportable hardware and software configuration which will be upgradeable through technology refreshments over the projected 20-year life span of LLWAS. Another goal is to enhance the functionality and windshear detection performance over existing systems by incorporating the LLWAS–3 Wind Shear and Microburst Detection (WSMD) algorithm into LLWAS–RS, and to enhance local and remote maintenance monitoring capabilities. In the separate relocation component of the LLWAS–RS program, some wind sensors will be relocated and a total of approximately 75 additional wind sensors will be installed among certain sites. The relocation effort will improve overall system effectiveness by expanding the coverage of the sensor network, and by correcting for situations where existing sensors are not optimally located or exposed.
LLWAS–RS is largely a Commercial-Off-The-Shelf (COTS) replacement system with corresponding acquisition and test approaches. The system consists of 6 to 32 remote stations each with a wind sensor and associated radio transceiver equipment, a master station central processor, and display devices. The WSMD algorithm processes the wind information to detect and provide real-time runway oriented microburst and windshear alerts. Airport centerfield winds and runway threshold winds for each protected runway are also supplied. The display devices include up to 24 Ribbon Display Terminals (RBDTs) for presenting wind information to controllers and supervisors in air traffic control tower. These displays are controlled by a display selection device which is used by supervisors to modify RBDT runway configurations. Up to 32 centerfield wind displays will also be provided to controllers in the Terminal Radar Approach Control (TRACON) room. At airports with a collocated TDWR, the wind data will be processed by TDWR and displayed on both the RBDTs and TDWR Geographic Situation Display (GSD). LLWAS–RS will include improved system software and maintenance diagnostics features. Maintenance and monitoring data will be supplied directly to the local maintenance technician through the system console which also provides a means for monitoring and changing system configuration files and parameters. Remote maintenance monitoring and diagnostics will be provided through an interface with the FAA national remote maintenance processing system. This paper will discuss the acquisition and implementation status of the LLWAS–RS system. A functional overview of the system along with technical descriptions for the sustainment and relocation components of the program will be furnished. This paper will also present a discussion on the technical and programmatic benefits in transitioning from the existing LLWAS systems to the LLWAS–RS system
The 8th Conference on Aviation, Range, and Aerospace Meteorology