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An assessment of the communications, navigation, surveillance (CNS) capabilities needed to support the future Air Traffic Management System

Published in:
MIT Lincoln Laboratory Report ATC-295

Summary

The purpose of this study was to assess the Communications, Navigation, and Surveillance (CNS) capabilities needed to support future Air Traffic Management (ATM) functionality in the National Airspace System (NAS). The goal was to determine the most effective areas for research and technical development in the CNS field and to make sure the decision support tools under development match future CNS capabilities. The requirements for future ATM functions were derived from high level operational concepts designed to provide more freedom and flexibility in flight operations and from the Joint Research Project Descriptions (JRPDs) that are listed in the Integrated Plan for Air Traffic Management Research and Technology Development. This work was performed for the FAA/NASA Interagency Air Traffic Management Integrated Product Team.
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Summary

The purpose of this study was to assess the Communications, Navigation, and Surveillance (CNS) capabilities needed to support future Air Traffic Management (ATM) functionality in the National Airspace System (NAS). The goal was to determine the most effective areas for research and technical development in the CNS field and to...

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Effects of metering precision and terminal controllability on runway throughput

Published in:
Air Traffic Control Q., Vol. 1, No. 3, July 1993, pp. 277-297.

Summary

In order to efficiently use available runway capacity while avoiding undue congestion within terminal airspace, systems of flow control and en route metering have been implemented. Recent work in automation has attempted to extend traffic flow planning to provide precise scheduling of traffic flow within the terminal area itself (from the metering fixes to the runways). The goal of this more detailed terminal scheduling is more efficient runway utilization. This article addresses an important practical question regarding the degree of precision required from the en route portion of such systems in order to allow the terminal scheduler to achieve its throughput benefits. The answer to this question determines the sophistication and rigidity required of en route automation and addresses the question of whether the success of new terminal automation is contingent upon improvements in en route metering. The method of analysis is mathematical modeling and fast-time computer simulation. A crucial parameter is controllability, which expresses the largest flight delay that the terminal scheduling can impose within the airspace available to it. The analysis reveals that achievable run-way utilization depends upon the type of metering employed, the available controllability within the terminal, and the extent to which controllers can be expected to intervene to handle transient peaks in arrival rates that cannot be handled by the automation. The major conclusion of the study is that in order to fully utilize a runway, the standard deviation of the errors in arrival time at the metering fixes should be kept to about half the terminal controllability. For the airports studied, there seems to be sufficient controllability available to allow a terminal scheduler to operate the runways at essentially full capacity when a metering system, even with modest delivery precision, is operating in the en route area.
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Summary

In order to efficiently use available runway capacity while avoiding undue congestion within terminal airspace, systems of flow control and en route metering have been implemented. Recent work in automation has attempted to extend traffic flow planning to provide precise scheduling of traffic flow within the terminal area itself (from...

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Impact of weather event uncertainty upon an optimum ground-holding strategy

Author:
Published in:
Air Traffic Control Q., Vol. 1, No. 1, January 1993, pp. 59-84.

Summary

When weather events are expected to produce significant delays at destination airports, the traffic flow management system in the United States holds departing aircraft on the ground in an attempt to reduce delay costs to the operator and to alleviate airborne congestion. Selecting the correct amount of ground holding is made difficult because of uncertainty in predicting weather events that produce congestion. In general, decision-makers must strike a balance between the amount of predicted delay absorbed on the ground and the amount absorbed in the air. This paper first addresses the question of how uncertainty in the required delay should influence the amount of ground holding. It then establishes the relationship between delay uncertainty and uncertainties in predicting the onset and duration of weather events. Delay costs are minimized under an assumption that there is a fixed ratio between the cost of a unit of ground delay and a unit of airborne delay and that the landing sequence employed at the destination terminal is based upon the originally scheduled landing order. The analysis indicates that uncertainty in the delay prediction must be considered in selecting the optimum amount of ground holding for an individual flight. In predicting delays, it is desirable to keep the ratio of the standard error to the mean delay (σ / μ) well below 1.0 in order to avoid loss of benefits. A corresponding figure of merit for weather systems is shown to be the ratio of the uncertainty in onset/termination times to the duration of the weather event. Weather prediction systems must keep this ratio well below one-third to avoid significant loss of ground-holding benefits. The analysis indicates that reductions in the delay uncertainty through improved weather forecasting and traffic management systems can result in better decision-making and significant cost savings.
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Summary

When weather events are expected to produce significant delays at destination airports, the traffic flow management system in the United States holds departing aircraft on the ground in an attempt to reduce delay costs to the operator and to alleviate airborne congestion. Selecting the correct amount of ground holding is...

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Air-to-air visual acquisition handbook

Author:
Published in:
MIT Lincoln Laboratory Report ATC-151

Summary

The document describes a set of computer programs that provide a practical means for predicting air-to-air visual acquisition performance for aircraft on collision courses. The programs are based upon a mathematical model of pilot visual acquisition performance. Guidelines are provided for selecting model parameters based upon previously collected flight test data. Selected results of computer analysis are provided.
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Summary

The document describes a set of computer programs that provide a practical means for predicting air-to-air visual acquisition performance for aircraft on collision courses. The programs are based upon a mathematical model of pilot visual acquisition performance. Guidelines are provided for selecting model parameters based upon previously collected flight test...

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Unalerted air-to-air visual acquisition

Author:
Published in:
MIT Lincoln Laboratory Report ATC-152

Summary

A series of flight tests were flown to measure pilot air-to-air visual acquisition performance for pilots employing unalerted visual search. Twenty-four general aviation subject pilots flew a cross-country route while an intercepting aircraft was controlled to produce three intercepts with altitude separation of 500 feet. Pilots received no traffic advisory information to alert them to the possible presence of the intercepting aircraft. Results were analyzed to estimate the instantaneous rate of visual acquisition for a visual target of specified size and contrast. The results were used to calibrate a mathematical model of visual acquisition that can be used to predict pilot performance under a range of conditions.
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Summary

A series of flight tests were flown to measure pilot air-to-air visual acquisition performance for pilots employing unalerted visual search. Twenty-four general aviation subject pilots flew a cross-country route while an intercepting aircraft was controlled to produce three intercepts with altitude separation of 500 feet. Pilots received no traffic advisory...

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Weather information requirements for terminal air traffic control automation

Published in:
Fourth Int. Conf. on Aviation Weather Systems, 24-28 June 1991, pp. 208-214.

Summary

Aviation operations in the airport terminal area, where flights converge from a number of directions onto one or two active runways, create a fundamental limitation on the capacity of the national airspace system. The U.S. Federal Aviation Administration (FAA) has recognized that the throughput of existing terminals can be increased significantly by providing the terminal air traffic control team with Terminal Air Traffic Control Automation (TATCA) tools that increase the efficiency of individual controller tasks and provide a dynamic, overall plan for traffic management throughout the terminal control region (Andrews and Welch, 1989). This latter function relies on accurate projection of traffic flow into the future (0-30 minutes) in order to automatically examine the many possible permutations of control actions. The result is a coordinated plan for the multiple (four to ten) control positions involved in the decision making processes that determine end-capacity at the runways. The FAA has launched an intensive effort to develop and implement TATCA capabilities by taking advantage of preparatory work done at NASA Ames Research Center, MITRE Corporation, and M.I.T. Lincoln Laboratory. An initial TATCA configuration, the Final Approach Spacing Tool (FAST), will be evaluated in the field beginning in 1993 and will be scheduled for possible national implementation two years later. Estimates of the economic value of TATCA-generated operational improvements, when implemented at major airports nationwide, are expected to be over $1 billion yearly by the year 2000 in reduced fuel consumption, other air carrier operating costs, and passenger time (Boswell et al., 1990). Since TATCA is first and foremost a planning system, the primary impacts of weather upon T ATCA performance involve disruption of planning. This can occur because of sudden or unexpected changes in routing, runway availability, or separation standards. In addition, errors in estimated wind produce errors in time-to-fly predictions made by the TATCA planning logic. The TATCA system must be robust with respect to weather events that commonly occur in its region of operation. This paper describes an initial study of the weather information requirements for TATCA, and their relationship to current and future systems for measurement, integration, forecasting and dissemination of meteorological data in the terminal area. A major goal is to stress the need for close coupling between ongoing initiatives in weather sensing/forecasting in the airport terminal area, and air-space capacity enhancement programs.
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Summary

Aviation operations in the airport terminal area, where flights converge from a number of directions onto one or two active runways, create a fundamental limitation on the capacity of the national airspace system. The U.S. Federal Aviation Administration (FAA) has recognized that the throughput of existing terminals can be increased...

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Planning horizon requirements for automated terminal scheduling

Published in:
Proc. 35th Annual Air Traffic Control Association Mtg., 16-20 September 1990, pp. 438-451.

Summary

This paper presents the results of an engineering analysis of the ability of an automated terminal scheduling process to achieve efficient use of runways. The motivation for the analysis is the need to understand possible architectures for an implementation of the proposed Terminal Air Traffic Automation (TATCA) system. The performance of TATCA is dependent upon metering precision and the controllability that TATCA can apply to aircraft entering the scheduling process. Controllability refers to the amount of time by which the flight time of an aircraft can be lengthened or shortened between the scheduling horizon and the chosen runway. The analysis concludes that when current en route metering mechanisms are used to deliver traffic to the terminal, the terminal scheduler meets a controllability window of 300 seconds or so in order to achieve full runway utilization. Because this amount of controllability is often achievable within the terminal area itself, a TATCA system can provide significant benefits prior to the implementation of further improvements in the en route metering process.
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Summary

This paper presents the results of an engineering analysis of the ability of an automated terminal scheduling process to achieve efficient use of runways. The motivation for the analysis is the need to understand possible architectures for an implementation of the proposed Terminal Air Traffic Automation (TATCA) system. The performance...

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Analysis of the potential benefits of Terminal Air Traffic Control Automation (TATCA)

Published in:
Proc. 1990 American Control Conf., Vol. 1, 23-25 May 1990, pp.535-542

Summary

Terminal Air Traffic Control Automation (TATCA) is an FAA research and development program to provide computer-aided sequencing, spacing, and management of air traffic flows in terminal areas. This paper discusses technical and national economic benefits that are attainable with such a terminal automation program.
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Summary

Terminal Air Traffic Control Automation (TATCA) is an FAA research and development program to provide computer-aided sequencing, spacing, and management of air traffic flows in terminal areas. This paper discusses technical and national economic benefits that are attainable with such a terminal automation program.

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Experimental examination of the benefits of improved terminal air traffic control planning

Published in:
Lincoln Laboratory Journal, Vol. 2, No. 3, Fall 1989, pp. 527-536.

Summary

Airport capacity can be improved significantly-by precisely controlling the sequence and timing of traffic flow-even when airspace usage and procedures remain fixed. In a preliminary experiment, a plan for such sequencing and timing was applied in a simulation to a 70-min traffic sample observed at Boston's Logan Airport, and the result was a 13% increase in terminal throughput. A total of 2.2 aircraft flight hours were saved. Delays imposed upon arriving traffic in the simulation were much more equitably distributed than in the actual traffic sample. An even greater improvement may be possible if controllers are able to space aircraft more precisely on final approach than was achieved in the simulation. If the plan had been followed precisely, the throughput increase would have been 23%.
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Summary

Airport capacity can be improved significantly-by precisely controlling the sequence and timing of traffic flow-even when airspace usage and procedures remain fixed. In a preliminary experiment, a plan for such sequencing and timing was applied in a simulation to a 70-min traffic sample observed at Boston's Logan Airport, and the...

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Pilot evaluation of TCAS in the Long Ranger helicopter

Author:
Published in:
MIT Lincoln Laboratory Report ATC-136

Summary

A specially modified version of the Traffic Alert and Collision Avoidance System (TCAS) was installed in a Bell Long Ranger helicopter in order to investigate the feasibility of TCAS operation in rotorcraft. This installation employed TCAS air-to-air surveillance to provide automated traffic advisories that were displayed in the cockpit on a color cathod ray tube display. As part of this study, 12 subject pilots evaluated the utility of the installation thorugh brief test flights in the vicinity of a major airport. Among the topics investigated were the rate of alarms, the computer logic for issuing advisories, the bearing accuracy, and the display symbology. Several recommendations for adapting TCAS to the rotorcraft environment resulted from the testing.
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Summary

A specially modified version of the Traffic Alert and Collision Avoidance System (TCAS) was installed in a Bell Long Ranger helicopter in order to investigate the feasibility of TCAS operation in rotorcraft. This installation employed TCAS air-to-air surveillance to provide automated traffic advisories that were displayed in the cockpit on...

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