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Wind information requirements for NextGen operations, phase 5 report

Published in:
MIT Lincoln Laboratory Report ATC-439

Summary

NextGen applications with time-based control elements, such as required time of arrival (RTA) at a meter fix under 4D trajectory-based operations (4D-TBO)/time of arrival control (TOAC) procedures or assigned spacing goal between aircraft under Interval Management (IM) procedures, are subject to the quality of the atmospheric forecast utilized by participating aircraft. The work described in this report summarizes the major activities conducted in the current phase of this program which builds upon prior work. The major objectives were: 1. Support RTCA Special Committee-206 Aeronautical Information and Meteorological Data Link Services and co-chair a sub-group responsible for developing the document "Guidance for Data Linking Forecast and Real-Time Wind Information to Aircraft." 2. Analyze the performance of publicly available forecast as compared to in-situ reported atmospheric conditions, specifically comparing Global Forecast System (GFS) and High Resolution Rapid Refresh (HRRR) forecast data to recorded in-flight weather Meteorological Data Collection and Reporting System (MDCRS) data. 3. Analyze current and future Flight Management Systems (FMSs) to conduct operations at significantly lower altitudes than previous studies. 4. Evaluate potential sources of aircraft-derived winds to better support 4D-TBO activities. 5. Provide recommendations for high-value future work.
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Summary

NextGen applications with time-based control elements, such as required time of arrival (RTA) at a meter fix under 4D trajectory-based operations (4D-TBO)/time of arrival control (TOAC) procedures or assigned spacing goal between aircraft under Interval Management (IM) procedures, are subject to the quality of the atmospheric forecast utilized by participating...

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A new radio frequency interference filter for weather radars

Author:
Published in:
J. Atmos. Ocean. Technol., Vol. 34, No. 7, 1 July 2017, pp. 1393-1406.

Summary

A new radio frequency interference (RFI) filter algorithm for weather radars is proposed in the two-dimensional (2D) range-time/sample-time domain. Its operation in 2D space allows RFI detection at lower interference-to-noise or interference-to-signal ratios compared to filters working only in the sample-time domain while maintaining very low false alarm rates. Simulations and real weather radar data with RFI are used to perform algorithm comparisons. Results are consistent with theoretical considerations and show the 2D RFI filter to be a promising addition to the signal processing arsenal against interference with weather radars. Increased computational burden is the only drawback relative to filters currently used by operational systems.
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Summary

A new radio frequency interference (RFI) filter algorithm for weather radars is proposed in the two-dimensional (2D) range-time/sample-time domain. Its operation in 2D space allows RFI detection at lower interference-to-noise or interference-to-signal ratios compared to filters working only in the sample-time domain while maintaining very low false alarm rates. Simulations...

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Report on the 2016 CoSPA and Traffic Flow Impact operational demonstration

Published in:
MIT Lincoln Laboratory Report ATC-433

Summary

This technical report summarizes the operational observations recorded by MIT Lincoln Laboratory (MIT LL) aviation subject matter experts during the period 1 June to 31 October 2016. The MIT LL observation team visited three Federal Aviation Administration (FAA) Air Route Traffic Control Centers (ARTCC) and the Air Traffic Control System Command Center (ATCSCC) on three separate convective events covering four days during the summer of 2016. Five commercial airlines were also involved in the observations. Specifically noted were the utilization of the deterministic convective weather forecasting model, Storm Prediction for Aviation (CoSPA), and a newly developed decision support application, Traffic Flow Impact (TFI). These field evaluations were supported via the FAA AJM-334 program.
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Summary

This technical report summarizes the operational observations recorded by MIT Lincoln Laboratory (MIT LL) aviation subject matter experts during the period 1 June to 31 October 2016. The MIT LL observation team visited three Federal Aviation Administration (FAA) Air Route Traffic Control Centers (ARTCC) and the Air Traffic Control System...

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Wind information requirements for NextGen applications phase 4 final report

Summary

The success of many NextGen applications with time-based control elements, such as Required Time of Arrival (RTA) at a meter fix under 4D-Trajectory Based Operations (4D-TBO/Time of Arrival Control (TOAC) procedures or compliance to an Assigned Spacing Goal (ASG) between aircraft under Interval Management (IM) procedures, are subject to the quality of the atmospheric forecast utilized by participating aircraft. Erroneous information derived from provided forecast data, such as the magnitude of future headwinds relative to the headwinds actually experienced during flight, or forecast data that is insufficient to fully describe the forthcoming atmospheric conditions, can significantly degrade the performance of an attempted procedure. The work described in this report summarizes the major activities conducted in Fiscal Year 2015.
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Summary

The success of many NextGen applications with time-based control elements, such as Required Time of Arrival (RTA) at a meter fix under 4D-Trajectory Based Operations (4D-TBO/Time of Arrival Control (TOAC) procedures or compliance to an Assigned Spacing Goal (ASG) between aircraft under Interval Management (IM) procedures, are subject to the...

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WSR-88D chaff detection and characterization using an optimized hydrometeor classification algorithm

Published in:
18th Conf. on Aviation, Range, and Aerospace Meteorology, 23-26 January 2017.

Summary

Chaff presents multiple issues for aviation, air traffic controllers, and the FAA, including false weather identification and areas where flight paths may need to be altered. Chaff is a radar countermeasure commonly released from aircraft across the United States and is comprised of individual metallic strands designed to reflect certain wavelengths. Chaff returns tend to look similar to weather echoes in the reflectivity factor and radial velocity fields, and can appear as clutter, stratiform precipitation, or deep convection to the radar operator or radar algorithms. When polarimetric fields are taken into account, however, discrimination between weather and non-weather echoes has relatively high potential for success. In this work, the operational Hydrometeor Classification Algorithm (HCA) on the WSR-88D is modified to include a chaff class that can be used as input to a Chaff Detection Algorithm (CDA). This new class is designed using human-truthed chaff datasets for the collection and quantification of variable distributions, and the collected chaff cases are leveraged in the tuning of algorithm weights through the use of a metaheuristic optimization. A final CDA uses various image processing techniques to deliver a filtered output. A discussion regarding WSR-88D observations of chaff on a broad scale is provided, with particular attention given to observations of negative differential reflectivity during different stages of chaff fallout. Numerous cases are presented for analysis and characterization, both as an HCA class and as output from the filtered CDA.
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Summary

Chaff presents multiple issues for aviation, air traffic controllers, and the FAA, including false weather identification and areas where flight paths may need to be altered. Chaff is a radar countermeasure commonly released from aircraft across the United States and is comprised of individual metallic strands designed to reflect certain...

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The Offshore Precipitation Capability

Summary

In this work, machine learning and image processing methods are used to estimate radar-like precipitation intensity and echo top heights beyond the range of weather radar. The technology, called the Offshore Precipitation Capability (OPC), combines global lightning data with existing radar mosaics, five Geostationary Operational Environmental Satellite (GOES) channels, and several fields from the Rapid Refresh (RAP) 13 km numerical weather prediction model to create precipitation and echo top fields similar to those provided by existing Federal Aviation Administration (FAA) weather systems. Preprocessing and feature extraction methods are described to construct inputs for model training. A variety of machine learning algorithms are investigated to identify which provides the most accuracy. Output from the machine learning model is blended with existing radar mosaics to create weather radar-like analyses that extend into offshore regions. The resulting fields are validated using land radars and satellite precipitation measurements provided by the National Aeronautics and Space Administration (NASA) Global Precipitation Measurement Mission (GPM) core observatory satellite. This capability is initially being developed for the Miami Oceanic airspace with the goal of providing improved situational awareness for offshore air traffic control.
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Summary

In this work, machine learning and image processing methods are used to estimate radar-like precipitation intensity and echo top heights beyond the range of weather radar. The technology, called the Offshore Precipitation Capability (OPC), combines global lightning data with existing radar mosaics, five Geostationary Operational Environmental Satellite (GOES) channels, and...

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The threat to weather radars by wireless technology

Published in:
Amer. Meteor. Soc., Vol. 97, No. 7, 1 July 2016, pp. 1159-67, doi: 10.1175/BAMS-D-15-00048.1.

Summary

Wireless technology, such as local area telecommunication networks and surveillance cameras, causes severe interference for weather radars, because they use the same operational radio frequencies. One or two disturbances can be removed from the radar image, but the number and power of the interfering wireless devices are growing all over the world, threatening that one day the radars could not be used at all. Some agencies have already changed or are considering changing frequency bands, but now even other bands are under threat. Use of equipment at radio frequencies is regulated by laws and international agreements. Technologies have been developed for peaceful co-existence. If wireless devices use these technologies to protect weather radars, their data transmission capabilities become limited, so it is tempting to violate the regulations. Hence, it is an important task for the worldwide weather community to involve themselves in the radio-frequency management process and work in close contact with their National Radio Authorities to ensure that meteorological interests be duly taken into account in any decision making process toward the future usage of wireless devices.
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Summary

Wireless technology, such as local area telecommunication networks and surveillance cameras, causes severe interference for weather radars, because they use the same operational radio frequencies. One or two disturbances can be removed from the radar image, but the number and power of the interfering wireless devices are growing all over...

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2015 operational observation of CoSPA and traffic flow impact

Published in:
MIT Lincoln Laboratory Report ATC-429

Summary

This technical report summarizes the operational observations recorded by MIT Lincoln Laboratory (MIT LL) aviation subject matter experts during the period 13 April to 31 October 2015. Three separate field observations were conducted over four convective weather days across the eastern National Airspace System (NAS) with visits to five separate FAA facilities and five different airline operation centers. Observations of strategic management planning and decision making were documented during these visits. Specifically noted were the utilization of the deterministic convective weather forecasting model, CoSPA, and a newly developed decision support application, Traffic Flow Impact (TFI). These field evaluations were supported via the FAA AJM-334 CoSPA program.
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Summary

This technical report summarizes the operational observations recorded by MIT Lincoln Laboratory (MIT LL) aviation subject matter experts during the period 13 April to 31 October 2015. Three separate field observations were conducted over four convective weather days across the eastern National Airspace System (NAS) with visits to five separate...

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Wind Information Requirements for NextGen Applications - Phase 3 Final Report(3.98 MB)

Published in:
Project Report ATC-422, MIT Lincoln Laboratory

Summary

Many NextGen applications depend on access to high accuracy wind data due to time-based control elements, such as required time of arrival at a meter fix under 4D-Trajectory-Based Operations/Time of Arrival Control procedures or compliance to an assigned spacing goal between aircraft under Interval Management procedures. The work described in this report summarizes the activities conducted in FY14, which builds upon prior work.
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Summary

Many NextGen applications depend on access to high accuracy wind data due to time-based control elements, such as required time of arrival at a meter fix under 4D-Trajectory-Based Operations/Time of Arrival Control procedures or compliance to an assigned spacing goal between aircraft under Interval Management procedures. The work described in...

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Wind information requirements for NextGen applications, phase 3 final report

Published in:
MIT Lincoln Laboratory Report ATC-422
Topic:

Summary

Many NextGen applications depend on access to high accuracy wind data due to time-based control elements, such as required time of arrival at a meter fix under 4D-Trajectory-Based Operations/Time of Arrival Control procedures or compliance to an assigned spacing goal between aircraft under Interval Management procedures. Any errors in the ground and/or aircraft wind information relative to the truth winds actually flown through can significantly degrade the performance of the procedure. Unacceptable performance could be mitigated by improving wind information in the aircraft, for example, by using higher accuracy wind forecast models to generate wind inputs for the ground or airborne systems, updating wind information more frequently, or to upgrade the way winds are handled in the avionics systems. The work described in this report summarizes the activities conducted in FY14, which builds upon prior work. It (1) establishes the relationship of wind information accuracy to 4D-TBO and IM performance for a selection of operationally relevant scenarios to identify wind needs to support them, and (2) presents examples of what wind information content and update rate to the aircraft will deliver a given target performance level to help inform concept of operations development and datalink technology needs.
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Summary

Many NextGen applications depend on access to high accuracy wind data due to time-based control elements, such as required time of arrival at a meter fix under 4D-Trajectory-Based Operations/Time of Arrival Control procedures or compliance to an assigned spacing goal between aircraft under Interval Management procedures. Any errors in the...

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