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Integrated Terminal Weather System (ITWS) 1992 Annual Report

September 7, 1993
  |
Project Report
Author:
James E. Evans
Published in:
MIT Lincoln Laboratory Report ATC-203
Topic:
weather
R&D area:
R&D group:

Summary

Hazardous weather in the terminal area is the major cause of aviation system delays as well as a principal cause of air carrier accidents. Several systems presently under development will provide significant increases in terminal safety. However, these systems will not make a major impact on weather-induced delays in the terminal area, meet a number of the safety needs (such as information to support ground deicing decisions), or reduce the workload of the terminal controller. The Integrated Terminal Weather System (ITWS) will provide improved aviation weather information in the allocated TRACON area (up to 50 nmi from the airport) by integrating data and products from various Federal Aviation Administration (FAA) and National Weather Service (NWS) sensors and weather information systems. The data from these sources will be combined to provide a unified set of safety and planning weather products for pilots, controllers, and terminal area traffic managers. by using data from multiple sensors, ITWS can generate important new products where no individual sensor alone could generate a single, reliable product. In other instances, use of data from several sources can compensate for erroneous data from one sensor and thus improve the overall integrity of existing products. Major objectives of the ITWS program are to increase the effective airport acceptance rate in adverse weather by rpoviding information to support terminal automation systems, better terminal route planning, and wake vortex advisory services, and to reduce the need for controllers to communicate weather information to pilots via VHF voice. This report summarizes the work acocmplished during fiscal year 1992 on the development of the ITWS initial operational capability products; functional prototype design; operation of testbeds to acquire data for product development and testing; operation evaluation of products by ATC users; investigation of approaches for effective transfer of the technology to the production contractor; transfer of products to pilots via digital data links; and technical support for the ITWS documents required by the General Accounting Office (GAO).
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Summary

Hazardous weather in the terminal area is the major cause of aviation system delays as well as a principal cause of air carrier accidents. Several systems presently under development will provide significant increases in terminal safety. However, these systems will not make a major impact on weather-induced delays in the...

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Integrated Terminal Weather System (ITWS) 1992 Annual Report

Assessment of the benefits for improved terminal weather information

August 2, 1993
  |
Conference Paper
Author:
James E. Evans
…
Published in:
5th Int. Conf. on Aviation Weather Systems, 2-6 August 1993, pp. 414-416.
Topic:
aviation weather
R&D area:
R&D group:

Summary

An important part of the FAA Aviation Weather Development Program is a system, the Integrated Terminal Weather System (ITWS), that will acquire data from the various FAA and National Weather Service (NWS) sensors and combine these with products from other systems (e.g., NWS Weather Forecast Offices and the FAA Aviation Weather Products Generator). This wide variety of input data and products will enable the ITWS to provide a unified set of weather products for safety and planning/capacity improvement for use in the terminal area by pilots, controllers, terminal area traffic managers, airlines, airports, and terminal automation systems (e.g., Terminal Air Traffic Control Automation (TATCA) Center Tracon Advisory System (CTAS) [Andrews and Welch, 1989] and wake vortex advisory systems.
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Summary

An important part of the FAA Aviation Weather Development Program is a system, the Integrated Terminal Weather System (ITWS), that will acquire data from the various FAA and National Weather Service (NWS) sensors and combine these with products from other systems (e.g., NWS Weather Forecast Offices and the FAA Aviation...

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Assessment of the benefits for improved terminal weather information

Role of the aviation weather system in providing a real-time ATC volcanic ash advisory system

August 2, 1993
  |
Conference Paper
Author:
James E. Evans
…
Published in:
5th Conf. on Aviation Weather Systems, 2-6 August 1993.
Topic:
aviation weather
R&D area:
R&D group:

Summary

Inadvertent engine ingestion of volcanic ash has caused expensive damage to a number of aircraft recently and could have caused accidents in at least two cases [Casadevall, 1993]. Consequently, there is great interest in a real-time air traffic control (ATC) volcanic ash advisory system which could provide timely warnings of operationally significant ash concentrations to planes in flight as well as information for flight planning. The current system (see figure 1) is characterized by non-automatic determination of ash eruption characteristics (especially altitudes) with trajectory analysis based on the National Meteorological Center (NMC) forecast winds being used to provide warnings of future locations. SIGNETS and Airport Weather Advisories are the principal means of providing information on the ash locations to pilots and controllers. After one to three days, volcanic ask from Alaska can be transported over major portions of the US aviation system (figure 2) [Heffter, et al. 1990]. The operational use of the ash trajectory predictions which do not provide information on hazard associated with the ask density has resulted in more frequent disruption of air traffic. The most recent example was an incident on 19 September 1992 where a 17 September eruption from Mt. Spurr in Alaska resulted in a significant disruption of air traffic in the Upper Midwest. A workshop in Washington, DC [Machol, 1993] discussed many of these issues associated with the Spurr disruption and the operational response to ash clouds which had been drifting for several days.
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Summary

Inadvertent engine ingestion of volcanic ash has caused expensive damage to a number of aircraft recently and could have caused accidents in at least two cases [Casadevall, 1993]. Consequently, there is great interest in a real-time air traffic control (ATC) volcanic ash advisory system which could provide timely warnings of...

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Role of the aviation weather system in providing a real-time ATC volcanic ash advisory system

Status of the Terminal Doppler Weather Radar with deployment underway

August 2, 1993
  |
Conference Paper
Author:
Donald H. Turnbull
…
Published in:
Proc. Fifth Int. Conf. on Aviation Weather Systems, 2-6 August 1993, pp. 32-34.
Topic:
air traffic control
R&D area:
R&D group:

Summary

The Federal Aviation Administration (FAA) initiated the Terminal Doppler Weather Radar (TDWR) program in the mid-1980's in response to the need for improved real-time hazardous weather (especially low-altitude wind shear) surveillance in the terminal area (Turnbull, et al., 1989). The initial focus for the TDWR was to provide reliable, fully automated Doppler radar detection of microbursts and gust fronts and 20-minute warning of wind shifts which could effect runway usage. Subsequent operational demonstrations have shown that the overall terminal situational awareness provided by the TDWR color Geographical Situation Display (GSD) depiction of wind shear locations, weather reflectivity and storm motion also yields substantial improvements in terminal operations efficiency for air traffic managers and for airlines. In this paper, we will describe the current status and deployment strategy for the operational systems and recent results from the extensive testing of the radar system concept and of the weather information dissemination approach.
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Summary

The Federal Aviation Administration (FAA) initiated the Terminal Doppler Weather Radar (TDWR) program in the mid-1980's in response to the need for improved real-time hazardous weather (especially low-altitude wind shear) surveillance in the terminal area (Turnbull, et al., 1989). The initial focus for the TDWR was to provide reliable, fully...

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Status of the Terminal Doppler Weather Radar with deployment underway

Role of FAA/NWS terminal weather sensors and terminal air traffic automation in providing a vortex advisory service

October 29, 1991
  |
Conference Paper
Author:
James E. Evans
…
Published in:
FAA Int. Wake Vortex Symp., Washington, DC, 29-31 October 1991.
Topic:
air traffic control
R&D area:
R&D group:

Summary

The Federal Aviation Administration (FAA) is developing a number of terminal weather sensors and a terminal weather information system which can make important contributions toward an operational wake vortex advisory service. Although these systems have been developed to meet other important weather information needs, their existence/development offers the possibility of a more cost effective wake vortex advisory system than would be possible with a standalone system such as was tested in the 1970's. Specifically, we postulate an advisory system in which the aircraft separation during IFR conditions is adjusted to account for the advection of vortices by the wind on the approach path and/or the breakup of vortices due to air instability and in which the desired aircraft separation is achieved by the Terminal Air Traffic Automation (TATCA) system. When reduced separations are obtained with such a system, it is important to be able to anticipate that the winds/vortex stability in the terminal area will continue to meet the reduced spacing criteria for an appropriate time interval (e.g., at least 15 minutes) in the future.
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Summary

The Federal Aviation Administration (FAA) is developing a number of terminal weather sensors and a terminal weather information system which can make important contributions toward an operational wake vortex advisory service. Although these systems have been developed to meet other important weather information needs, their existence/development offers the possibility of...

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Role of FAA/NWS terminal weather sensors and terminal air traffic automation in providing a vortex advisory service

Development of a real-time ATC volcanic ash advisory system based on the aviation weather system

July 8, 1991
  |
Conference Paper
Author:
James E. Evans
Published in:
1st Int. Symp. on Volcanic Ash and Aviation Safety, Seattle, WA, 8-12 July 1991.
Topic:
aviation weather
R&D area:
R&D group:

Summary

There is a need for a real-time volcanic ash advisory system for aviation which could provide improved accuracy and timeliness in warnings to planes in flight as well as to air traffic controllers for flight planning. To provide an operationally useful capability at reasonable cost, it is essential that the system elements take maximum advantage of the weather sensing and information dissemination system under development by the FAA and NWS. Volcanic ash should be treated as a type of weather hazard similar to regions of icing and thunderstorms. Real-time information from ground sensors, unmanned air vehicles, air carriers, and satellites would be used to estimate current and predicted ash systems to pilots in flight, ATC controllers, traffic management units and airlines. Future research should focus on defining the ash densities and time exposures of concern to aircraft, resolving the sensor mix for measuring the ash density and extent, and validating models for ash transport.
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Summary

There is a need for a real-time volcanic ash advisory system for aviation which could provide improved accuracy and timeliness in warnings to planes in flight as well as to air traffic controllers for flight planning. To provide an operationally useful capability at reasonable cost, it is essential that the...

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Development of a real-time ATC volcanic ash advisory system based on the aviation weather system

Status of the Terminal Doppler Weather Radar - one year before deployment

June 24, 1991
  |
Conference Paper
Author:
James E. Evans
Published in:
25th Int. Conf. on Radar Meteorology, Paris, France, 24-28 June 1991, pp. J1-J6.
Topic:
aviation weather
R&D area:
R&D group:

Summary

The Federal Aviation Administration (FAA) initiated the Terminal Doppler Weather Radar (TDWR) program in the mid-1980s in response to the need for improved real time hazardous weather (especially low altitude wind shear) detection in the terminal area. The program is designed to develop a reliable automated Doppler radar based system to detect terminal weather hazards and provide warnings that will help pilots successfully avoid these hazards. Following the successful operational evaluation of the TDWR concept which was described at the last conference, a production contract was awarded to the Raytheon Company, with the first deliveries scheduled for fall of 1992. This paper will describe the current status and deployment strategy for the operational systems and present recent results from the extensive testing of the radar system concept and weather information dissemination approach.
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Summary

The Federal Aviation Administration (FAA) initiated the Terminal Doppler Weather Radar (TDWR) program in the mid-1980s in response to the need for improved real time hazardous weather (especially low altitude wind shear) detection in the terminal area. The program is designed to develop a reliable automated Doppler radar based system...

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Status of the Terminal Doppler Weather Radar - one year before deployment

Results of the Kansas City 1989 Terminal Doppler Weather Radar (TDWR) operational evaluation testing

August 17, 1990
  |
Project Report
Author:
James E. Evans
Published in:
MIT Lincoln Laboratory Report ATC-171
Topic:
weather
R&D area:
R&D group:

Summary

The Lincoln Laboratory Terminal Doppler Weather Radar (TDWR) testbed was used to carry out an experimental and operational hazardous weather product evaluation program for the Federal Aviation Administration (FAA) at the Kansas City International (KCI) Airport during the summer of 1989. The objective of the program was to test and refine previously tested techniques for the automatic detection of low-altitude wind shear phenomena (specifically microbursts and gust fronts) and heavy precipitation in a midwest weather environment, as well as to assess possible new products such as storm movement predictions. A successful operational evaluation of the TDWR products took place at the KCI tower and terminal radar control room (TRACON) from 15 July to 15 August 1989 and from 15 to 30 September 1989. Several supervisor and controller display refinements that had been determined from the 1988 operational evaluation at Denver were assessed as effective. The system was successful in terms of aircraft at KCI avoiding wind shear encounters during the operational period, and it was assessed as "very good" in usefulness for continuing operation by the KCI air traffic control (ATC) personnel.
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Summary

The Lincoln Laboratory Terminal Doppler Weather Radar (TDWR) testbed was used to carry out an experimental and operational hazardous weather product evaluation program for the Federal Aviation Administration (FAA) at the Kansas City International (KCI) Airport during the summer of 1989. The objective of the program was to test and...

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Results of the Kansas City 1989 Terminal Doppler Weather Radar (TDWR) operational evaluation testing

Clutter rejection in Doppler weather radars used for airport wind shear detection

June 1, 1990
  |
Conference Paper
Author:
James E. Evans
…
Published in:
Proc. Second Int. Symp. on Noise & Clutter Rejection in Radars & Imaging Sensors (ISNCR-89), 14-16 November 1989, PP. 275-280.
Topic:
aviation weather
R&D area:
R&D group:

Summary

Techniques for the suppression of ground and storm clutter to permit the detection of low altitude windshear by pulse Doppler radars are described. Novel features of the system include the use of clutter residue and range aliased weather echo editing maps which edit out the range-azimuth cells on a "data adaptive" basis.
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Summary

Techniques for the suppression of ground and storm clutter to permit the detection of low altitude windshear by pulse Doppler radars are described. Novel features of the system include the use of clutter residue and range aliased weather echo editing maps which edit out the range-azimuth cells on a "data...

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Clutter rejection in Doppler weather radars used for airport wind shear detection

Terminal Doppler Weather Radar clutter control

May 10, 1990
  |
Conference Paper
Author:
James E. Evans
…
Published in:
Proc. IEEE 1990 Int. Radar Conf., 7-10 May 1990, pp. 12-16.
Topic:
aviation weather
R&D area:
R&D group:

Summary

The FAA is developing the Terminal Doppler Weather Radar system to automatically detect low altitude wind shear due to microbursts and gust fronts. Detection of this phenomenon presents a significant radar engineering challenge due to the need to observe low reflectivity events in the presence of strong clutter from ground objects and range aliased weather returns. This paper describes a number of unique approaches to clutter recognition which have been validated with the TDWR test bed radar.
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Summary

The FAA is developing the Terminal Doppler Weather Radar system to automatically detect low altitude wind shear due to microbursts and gust fronts. Detection of this phenomenon presents a significant radar engineering challenge due to the need to observe low reflectivity events in the presence of strong clutter from ground...

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Terminal Doppler Weather Radar clutter control
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