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Benefits assessment methodology for an air traffic control tower advanced automation system

September 13, 2010
  |
Conference Paper
Author:
Thomas G. Reynolds
…
Published in:
ATIO 2010: 10th AIAA Aviation Technology Integration and Operations Conf., 13-15 September 2010.
Topic:
air traffic control
R&D area:
R&D group:

Summary

This paper presents a benefits assessment methodology for an air traffic control tower advanced automation system called the Tower Flight Data Manager (TFDM), which is being considered for development by the FAA to support NextGen operations. The standard FAA benefits analysis methodology is described, together with how it has been tailored to the TFDM application to help inform the development process and the business case for system deployment. Parts of the methodology are illustrated through data analysis and modeling, and insights are presented to help prioritize TFDM capability development.
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Summary

This paper presents a benefits assessment methodology for an air traffic control tower advanced automation system called the Tower Flight Data Manager (TFDM), which is being considered for development by the FAA to support NextGen operations. The standard FAA benefits analysis methodology is described, together with how it has been...

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Benefits assessment methodology for an air traffic control tower advanced automation system

On estimating mid-air collision risk

September 13, 2010
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Conference Paper
Author:
Mykel J. Kochenderfer
…
Published in:
ATIO 2010: 10th AIAA Aviation Technology Integration and Operations Conf., 13-15 September 2010.
Topic:
air traffic control
R&D area:
R&D group:

Summary

Many aviation safety studies involve estimating near mid-air collision (NMAC) rate. In the past, it has been assumed that the probability that an NMAC leads to a mid-air collision is 0.1, but there has not yet been a comprehensive study to serve as a basis for this estimate. This paper explains how to use existing encounter models, a flight simulation framework, three-dimensional aircraft wireframe models, and surveillance data to estimate mid-air collision risk. The results show that 0.1 is an overly conservative estimate and that the true rate is likely to be an order of magnitude lower.
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Summary

Many aviation safety studies involve estimating near mid-air collision (NMAC) rate. In the past, it has been assumed that the probability that an NMAC leads to a mid-air collision is 0.1, but there has not yet been a comprehensive study to serve as a basis for this estimate. This paper...

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On estimating mid-air collision risk

Traffic Management Advisor (TMA) weather integration

August 10, 2010
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Project Report
Author:
Michael Robinson
…
Published in:
MIT Lincoln Laboratory Report ATC-364
Topic:
air traffic control
R&D area:
R&D group:

Summary

TCAS behavior in New England airspace is being monitored and analyzed, making use of an omni-directional 1030/1090 MHz receiver. The receiver system, located in Lexington, MA, and operated by M.I.T. Lincoln Laboratory, is used to record Resolution Advisories (RAs). Omni-directional receptions make it possible to examine the air-to-air messages exchanged between aircraft for coordination of RAs. Omni-directional reception rates are also being studied. THe results indicated the percentage of aircraft that are TCAS equipped and the percentage of received signals that originate from TCAS and other systems. A third aspect of the program evaluates the availablity of 1090 MHz Extended Squitter data for use in collision avoidance systems. Data is recorded continuously, and the busiest periods are selected for focused attention.
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Summary

TCAS behavior in New England airspace is being monitored and analyzed, making use of an omni-directional 1030/1090 MHz receiver. The receiver system, located in Lexington, MA, and operated by M.I.T. Lincoln Laboratory, is used to record Resolution Advisories (RAs). Omni-directional receptions make it possible to examine the air-to-air messages exchanged...

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Traffic Management Advisor (TMA) weather integration

Collision avoidance for unmanned aircraft using Markov Decision Processes

August 2, 2010
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Conference Paper
Author:
Selim Temizer
…
Published in:
AIAA Guidance, Navigation, and Control Conf., 2-5 August 2010.
Topic:
collision avoidance
R&D area:
R&D group:

Summary

Before unmanned aircraft can fly safely in civil airspace, robust airborne collision avoidance systems must be developed. Instead of hand-crafting a collision avoidance algorithm for every combination of sensor and aircraft configuration, we investigate the automatic generation of collision avoidance algorithms given models of aircraft dynamics, sensor performance, and intruder behavior. By formulating the problem of collision avoidance as a Markov Decision Process (MDP) for sensors that provide precise localization of the intruder aircraft, or a Partially Observable Markov Decision Process (POMDP) for sensors that have positional uncertainty or limited field-of-view constraints, generic MDP/POMDP solvers can be used to generate avoidance strategies that optimize a cost function that balances flight-plan deviation with collision. Experimental results demonstrate the suitability of such an approach using four different sensor modalities and a parametric aircraft performance model.
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Summary

Before unmanned aircraft can fly safely in civil airspace, robust airborne collision avoidance systems must be developed. Instead of hand-crafting a collision avoidance algorithm for every combination of sensor and aircraft configuration, we investigate the automatic generation of collision avoidance algorithms given models of aircraft dynamics, sensor performance, and intruder...

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Collision avoidance for unmanned aircraft using Markov Decision Processes

Wind-shear system cost-benefit analysis

August 1, 2010
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Journal Article
Author:
Robert G. Hallowell
…
Published in:
Lincoln Laboratory Journal, Vol. 18, No. 2, August 20, pp. 47-68.
Topic:
aviation weather
R&D area:
R&D group:

Summary

Mitigating thunderstorm wind-shear threats for aircraft near the ground has been an important issue since the 1970s, when several fatal commercial aviation accidents were attributed to wind shear. Updating the knowledge base for airport wind-shear exposure and effectiveness of detection systems has become critical to the Federal Aviation Administration as they consider options for aging systems and evaluations of new systems.
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Summary

Mitigating thunderstorm wind-shear threats for aircraft near the ground has been an important issue since the 1970s, when several fatal commercial aviation accidents were attributed to wind shear. Updating the knowledge base for airport wind-shear exposure and effectiveness of detection systems has become critical to the Federal Aviation Administration as...

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Wind-shear system cost-benefit analysis

Predictive modeling of forecast uncertainty in the Route Availability Planning Tool (RAPT)

July 12, 2010
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Conference Paper
Author:
John T. Hayward
…
Published in:
2010 Intl. Conf. on Scientific Computing, CSC, 12-15 July 2010.
Topic:
aviation weather
R&D area:
R&D group:

Summary

MIT Lincoln Laboratory has developed the Route Availability Planning Tool (RAPT), which provides automated convective weather guidance to air traffic managers of the NYC metro region. Prior studies of RAPT have shown high-accuracy guidance from forecast weather, but further refinements to prevent forecast misclassification is still desirable. An attribute set of highly correlated predictors for forecast misclassification is identified. Using this attribute set, a variety of prediction models for forecast misclassification are generated and evaluated. Rule-based models, decision trees, multi-layer perceptrons, and Bayesian prediction model techniques are used. Filtering, resampling, and attribute selection methods are applied to refine model generation. Our results show promising accuracy rates for multi-layer perceptrons trained on full attribute sets.
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Summary

MIT Lincoln Laboratory has developed the Route Availability Planning Tool (RAPT), which provides automated convective weather guidance to air traffic managers of the NYC metro region. Prior studies of RAPT have shown high-accuracy guidance from forecast weather, but further refinements to prevent forecast misclassification is still desirable. An attribute set...

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Predictive modeling of forecast uncertainty in the Route Availability Planning Tool (RAPT)

OEP terminal and CONUS weather radar coverage gap identification analysis for NextGen

May 19, 2010
  |
Project Report
Author:
John Y. Cho
Published in:
MIT Lincoln Laboratory Report ATC-369
Topic:
air traffic control
R&D area:
R&D group:

Summary

The initial results of a weather radar coverage analysis in support of the Reduce Weather Impacts (RWI) Sensor RightSizing program are presented. The main impetus behind this study is to identify gaps in the radar network relative to the Next Generation Air Transportation System (NextGen) end-state performance requirements. Because detailed performance requirements are currently available only for super-density terminal airspace, we focused on this domain. We also analyzed, to a lesser extent, the contiguous United States (CONUS) airspace as an approximation to the en route airspace. Significant gaps were uncovered in the following requirement areas. (1) Vertical resolution. The current weather radar network (and any future radar network of reasonable cost) will not meet the 4D weather cube single authoritative source (4D WxSAS) vertical resolution requirements for both super-density terminal and en route airspace domains. (2) Vertical accuracy. Accurate determination of the radar beam height is difficult due to the natural variability of the vertical refractivitiy gradient in the atmosphere. (3) Update period for convective weather. The current weather radars have volume scan update periods that are substantially longer than the required times. (4) Horizontal resolution. This requirement is met in only some parts of the super-density terminal and en route airspaces (5) Low-altitude coverage. The current weather radars are generally spaced too far apart to provide seamless coverage of the boundary layer. (6) Overall terminal airspace weather radar coverage is significantly diminished due to terrain blockage at a handful of major airports.
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Summary

The initial results of a weather radar coverage analysis in support of the Reduce Weather Impacts (RWI) Sensor RightSizing program are presented. The main impetus behind this study is to identify gaps in the radar network relative to the Next Generation Air Transportation System (NextGen) end-state performance requirements. Because detailed...

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OEP terminal and CONUS weather radar coverage gap identification analysis for NextGen

Terminal Doppler Weather Radar enhancements

May 10, 2010
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Conference Paper
Author:
John Y. Cho
…
Published in:
IEEE Radar Conf., 10 May 2010, pp. 1245-1249.
Topic:
algorithms
R&D area:
R&D group:

Summary

The design of an open radar data acquisition system for the Terminal Doppler Weather Radar is presented. Adaptive signal transmission and processing techniques that take advantage of the enhanced capabilities of this new system are also discussed. Results displaying data quality improvements with respect to problems such as range-velocity ambiguity and moving clutter are shown.
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Summary

The design of an open radar data acquisition system for the Terminal Doppler Weather Radar is presented. Adaptive signal transmission and processing techniques that take advantage of the enhanced capabilities of this new system are also discussed. Results displaying data quality improvements with respect to problems such as range-velocity ambiguity...

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Terminal Doppler Weather Radar enhancements

CIWS product description, revision 1.0

April 30, 2010
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Project Report
Author:
Gregory W. Rappa
…
Published in:
MIT Lincoln Laboratory Report ATC-355
Topic:
weather
R&D area:
R&D group:

Summary

Lincoln Laboratory has developed a set of information models for the encoding and distribution of data products from the National Corridor Integrated Weather System (CIWS) prototype, currently operating at Lincoln Laboratory in Lexington, Massachusetts. CIWS data products can be categorized as gridded and non-gridded. Gridded products are typically expressed as rectangular arrays whose elements contain a data value coinciding with uniformly-spaced observations or computed results on a 2-D surface. Gridded data arrays map to earth's surface through a map projection, for example, Lambert Conformal or Lambert Azimuthal Equal-Area. Non-gridded data products express observations or computed results associated with singular or sparsely distributed sets of geo-spatial locations such as points, curves, or contours. CIWS prototype data products were used to develop, refine, and evaluate reference information models for the CIWS gridded and non-gridded data. Data packaging methods were evaluated and selected on the basis of public-domain open-source availability and metadata support. Network Common Data Format (NetCDF), provided by Unidata, was selected as the information model for gridded CIWS products. For the non-gridded products, XML schemas have been developed along with sample XML instances to illustrate schema-compliant product encodings. These models follow and extend upon a number of Open Geospatial Consortium (OGC) and ISO standards including Geography Markup Language (GML), Observations and Measurements (OM), and Eurocontrol's Weather Exchange Model (WXXM). This document is intended to serve as a reference for the description of CIWS data product files.
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Summary

Lincoln Laboratory has developed a set of information models for the encoding and distribution of data products from the National Corridor Integrated Weather System (CIWS) prototype, currently operating at Lincoln Laboratory in Lexington, Massachusetts. CIWS data products can be categorized as gridded and non-gridded. Gridded products are typically expressed as...

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CIWS product description, revision 1.0

Signal processing algorithms for the Terminal Doppler Weather Radar: Build 2

April 30, 2010
  |
Project Report
Author:
John Y. Cho
Published in:
MIT Lincoln Laboratory Report ATC-363
Topic:
signal processing
R&D area:
R&D group:

Summary

As a new radar data acquisition system (RDA) was developed for the Terminal Doppler Weather Radar (TDWR), enhanced signal processing algorithms taking advantage of its increased capabilities were also developed. The primary goals of protecting the base data estimates from range-aliased signals and providing reliable velocity dealiasing were achieved through multiple pulse repetition interval (PRI) and phase coding methods. An innovative radial-by-radial adaptive selection process was used to take full advantage of the different techniques, the first time such an approach has been implemented for weather radars. Improvement in clutter filtering was also achieved. This report discusses in detail these new RDA signal processing algorithms.
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Summary

As a new radar data acquisition system (RDA) was developed for the Terminal Doppler Weather Radar (TDWR), enhanced signal processing algorithms taking advantage of its increased capabilities were also developed. The primary goals of protecting the base data estimates from range-aliased signals and providing reliable velocity dealiasing were achieved through...

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Signal processing algorithms for the Terminal Doppler Weather Radar: Build 2
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