Air Traffic Control Automation Research Articles

Capturing Air Traffic Controller Expertise for Incorporation in Automated Air Traffic Control Systems

Under Federal Aviation Administration (FAA) sponsorship, MITRE's Human Performance Assessment Group is contributing to the design of an expert system to support air traffic control. We are working closely with a team of expert, full-performance-level air traffic controllers to capture the formal and informal rules they use in maintaining flight safety and efficiency. This paper documents our approach to working with these experts, the results of using that approach, and a distillation of lessons learned.

Application of Expert Systems in Air Traffic Control

Increased automation of air traffic control (ATC) systems appears to offer a solution to the dual problem of handling higher levels of air traffic while reducing the costs incurred by the ATC system itself and the aircraft under control. Because of the complexity of the ATC system, expert systems may provide a valuable addition to human decision making and conventional data processing in the design of future ATC systems. A number of potential applications, including traffic flow management, controller support functions, system failure management, training, and system configuration planning, are described, and the special requirements of expert systems developed for realtime control applications are discussed. The structure of a prototype expert system to assist in air traffic flow management is described. The paper concludes with a brief examination of the potential for applying similar techniques to other transportation control systems.

A physical basis for NEXRAD data update rates

The Next Generation Weather Radar (NEXRAD) is slated to play an important role in the integrated and automated air traffic control system being currently planned by the Federal Aviation Administration One major point of debate is the minimum rate at which weather data collected by NEXRAD must be updated so that no phenomena potentially hazardous to aviation go undetected This paper presents the methodology and results of a study to estimate the lifetimes of significant features in typical storm phenomena for situations other than takeoff or landing These results are of direct relevance in deciding NEXRAD system data update rates. Two methods are used for the lifetime study: photo interpretive and computer based correlation Several storms are studied using both methods It is found that the storms studied contain no feature that might have been missed by a 5-min scan cycle provided that concurrent reflectivity, radial velocity, and Doppler spectrum width data at several elevations are utilized in the detection of hazardous phenomena.

Air Traffic Flow Control Systems: Modelling and Evaluation

Some mathematical models for supporting the development of semi/ fully automated air traffic control systems are discussed. Particularly, the flow control problem is approached as a constrained optimization problem on a multicommodity network. The proposed mathematical model, by means of a suitable time discretization, is initially changed into a “static” one. Then a multicommodity algorithm, based on the resource directive decomposition method, is used for the actual computation of the optimal flow in the network. The method is evaluated from the point of view of its practical implementation and its capability to take into account the peculiar aspects of the problem. An application, relative to the Rome air traffic control region, is discussed.

The effect of increased monitoring load on vigilance performance using a simulated radar display.

The present study examined the extent to which level of target density influences the ability to sustain attention to a complex monitoring task requiring only a detection response to simple stimulus change. The visual display was designed to approximate a futuristic, highly automated air traffic control radar display containing computer-generated alphanumeric symbols. Forty-eight male subjects, equally divided into three groups, were exposed to density levels of 4, 8, or 16 targets. Ten critical stimuli (signals) were randomly presented during each half-hour of the 2 h session. Detection latency to the critical stimuli in the 16-target condition was significantly greater than latency to the 4- and 8-target conditions. There was no evidence of performance decrement in the two lower density conditions. The 16-target condition showed a significant progressive increase in mean detection latency, which was primarily the result of an increase in long latencies. The hypothesized decline in attention associated with this condition appeared to be independent of any major change in arousal level.

Four-dimensional guidance problem with control delays

This paper, assuming steady wind and zero sideslip, presents a discrete-time mathematical model to obtain a control law and three-dimensional flight path to guide an aircraft in a given time from a given initial state (position, velocity and heading) to a prescribed final state subject to the constraints on airspeed acceleration, and pitch and bank angles of the aircraft. For ease in implementing the control law, the control inputs are assumed to be delayed and are applied in a sequential fashion. The guidance problem is formulated as a discrete nonlinear optimal control problem with time delays in dynamics and a cost functional of Bolza form. With a quadratic penalty function to handle terminal constraints on velocity and heading, a solution technique to the control problem based on conjugate gradient algorithm is investigated. Numerical examples are presented to illustrate the applicability of this approach to solution of a terminal area guidance problem in an automated air traffic control environment.

The automation of air traffic control

The automation of air traffic control

The Automation of Air Traffic Control

Experience gained in the automation of air traffic control is of interest from more than one point of view, and not only because of the range and diversity of new and delicate problems to which this application of automation has given rise, and for which it is necessary to find simultaneous solutions. It has been necessary to design and develop new methods for the acquisition, processing and display of information and to link them with digital computers, for which a complex and voluminous ‘real-time’ software has had to be compiled and brought up to date without interrupting the procedure. But it is when it comes to visualizing the total pattern that the most difficult problems arise because the major decisions determining the success or failure of the operation have had to be taken without the possibility of acquiring any preliminary experience.Man and the computer have to work together in real time as harmoniously as possible to obtain the best results from the modern data processing systems that it was proposed to employ; it was therefore essential to consider very deeply the complementary roles which each was intended to play.To describe this research in detail or the solutions arrived at would not be of great interest to those other than specialists.

ＳＴＯＬ専用空港の離着陸容量に関する一研究

This paper is concerned with the determination of capacity of a single runway STOL port. An automated air traffic control procedure for landing and take-off is proposed which takes into consideration the delays of the aircraft to control commands, the variations of the approach speeds due to wind velocities, etc. Capacity of a single runway STOL port using the proposed procedure is determined, using digital simulations and queuing theory. The effect of various factors, such as length of common path, time and distance separation rules, the variations of the related quantities, etc. on the capacity is discussed.

Discrete optimal control approach to a four-dimensional guidance problem near terminal areas

Description of a computer-oriented technique to generate the necessary control inputs to guide an aircraft in a given time from a given initial state to a prescribed final state subject to the constraints on airspeed, acceleration, and pitch and bank angles of the aircraft. A discrete-time mathematical model requiring five state variables and three control variables is obtained, assuming steady wind and zero sideslip. The guidance problem is posed as a discrete nonlinear optimal control problem with a cost functional of Bolza form. A solution technique for the control problem is investigated, and numerical examples are presented. It is believed that this approach should prove to be useful in automated air traffic control schemes near large terminal areas.

The Development of the ATC Radar Beacon System: Past, Present, and Future

The ATC radar beacon system is a descendant, through an extended evolutionary development, of military identification friend or foe (IFF) systems begun during World War II. It is today's primary source of surveillance data for air traffic control and performs this function with a high degree of effectiveness. A number of programs are underway to correct its current deficiencies. Looking to the future, the further automation of air traffic control together with the projected growth of air traffic lead to requirements for improved surveillance and communication capability. A discreteaddress mode of beacon system operation, with integral ground-air-ground data link, is under development to meet these needs.

Guidance and Control Techniques for Automated Air Traffic Control

A guidance technique has been developed for flying an aircraft automatically along curved trajectories. The technique consists of a set of algorithms for automatically synthesizing flight profiles, i.e., the horizontal trajectory, the altitude and speed profiles, and a time sequence of commands. The flyability Of the synthesized profile under wind disturbances and initial condition error is verified by closing the loop around the synthesized trajectory and flying it in a computer-simul ated jet aircraft. A control law having longitudinal, lateral and heading deviation from the synthesized profile in the feedback loops is used for the simulated flight. The performance of the system is excellent, errors that are initially zero never exceed 230 ft and large initial errors are reduced rapidly. The system also behaves quite well under wind disturbance. For example, the longitudinal and lateral deviations never exceed 470 ft for a 10-knot error in estimated wind velocity. This paper presents the flight-profile synthesis algorithms, describes the control law, analyzes the overall system performance under initial errors and error in steady wind estimates, and discusses the simulation results.

航空交通管制自動化

航空交通管制自動化

Increasing runway capacity

Today's major urban airport operates at saturation too frequently but can be upgraded to increase substantially aircraft movement rates by means of a number of system changes. These changes provide for reduced separations between aircraft, use of additional parallels, and more precise control of terminal traffic. There are incremental steps which can be taken to improve the current situation. However, to achieve substantial increases in operating rates with acceptable safety levels, it is necessary to introduce a new landing aid, reconfigure runway designs, use higher quality flight control equipment, and provide ground-air-ground data links and better surveillance for traffic flow organization and conflict monitoring. These features can be used to retrofit current airports or to design new airports. The flexibilities afforded by a new landing system can also reduce noise pollution by permitting flight path geometries not now achievable. The capacity of a single runway can be increased in the near term by approximately 40 percent without changes in current separation standards. In the longer term, it is expected that single runway capacity can be more than doubled with the introduction of improved guidance, flight control, air traffic control automation, and surveillance. Airport acreage can be utilized more efficiently by closer spacing of independent IFR runways.

4D Trajectory Estimation for Air Traffic Control Automation System Based on Hybrid System Theory

To resolve the problem of future airspace management under great traffic flow and high density condition, 4D trajectory estimation has become one of the core technologies of the next new generation air traffic control automation system. According to the flight profile and the dynamics models of different aircraft types under different flight conditions, a hybrid system model that switches the aircraft from one flight stage to another with aircraft state changing continuously in one state is constructed. Additionally, air temperature and wind speed are used to modify aircraft true airspeed as well as ground speed, and the hybrid system evolution simulation is used to estimate aircraft 4D trajectory. The case study proves that 4D trajectory estimated through hybrid system model can image the flight dynamic states of aircraft and satisfy the needs of the planned flight altitude profile.KEY WORDSair traffic management, 4D trajectory estimation, hybrid system model, aircraft dynamic model

A projection of future ATC data processing requirements

Forecast traffic growth for the 1980-1995 time period will exceed the capacity of the present airport and air traffic control automation system in high-density areas. If traffic growth is to be accommodated, higher levels of automation are required. The Department of Transportation Air Traffic Control Advisory Committee (September 1968-August 1969) established a computer sizing group to determine the feasibility of achieving the necessary level of automation within the projected technology. This paper presents a model of the future system, a summary of the functions automated, and estimates of the necessary computer instruction rate and storage requirements as developed by this computer sizing group.

Future trends of radio and radar navigation

The paper compares the requirements for marine and aeronautical navigation. In radio navigation a knowledge of the path of the radio waves and the velocity of wave propagation along the path is essential. Distance-bearing navigation, hyperbolic navigation and radio Doppler navigation are considered. The new techniques of navigation discussed are inertial, mobile high stability sources, very low radio frequencies, radio telescopes and earth satellites. Systems for berthing ships and landing aircraft during bad visibility are described. The paper concludes with some proposals for automation in air traffic control.