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This report describes a development and evaluation program for Differential Omega in general aviation. The program was a cooperative venture between the FAA and Transport Canada. SCT performed system design, program management, and flight test on behalf of the FAA. Tracor, Inc. provided modified Omega airborne receivers under subcontract to SCT. Flight tests took place in Alaska aboard a Convair 580 provided by the FAA. Monitor stations were located in Anchorage and at Deadhorse. The most definitive results were obtained from flight tests conducted in October 1980 and February 1981. Important results included: (a) data-link range varied from 44 nm to 198 nm, (b) random component of navigation error was 0.25 nm, 2-D RMS, (c) range decorrelation error was about 2 nm over a distance of 550 nm, (d) transient response of the system-following aircraft procedure turns was characterized by a positional overshoot of about 1.5 nm, followed by a monotonically decreasing error with a two-minute time constant. Recommendations are made for improving system performance. (Author)

This report describes an evaluation of the Northeast Helicopter Corridor Routes (NEC). The Northeast Corridor is an experimental route between Boston and Washington, D.C., consisting of two, one-way, reduced width airways designed expressly for helicopter operations. The evaluation is a joint effort of the Federal Aviation Administration (FAA) and the Helicopter Association of America (HAA). The data being gathered is in the form of data extraction tapes from Automated Radar Terminal Service (ARTS) equipped air traffic control (ATC) facilities along the routes and flight logs submitted by the helicopter pilots after each corridor test flight. The test flights are being made as cooperating corporate helicopter operators fly the corridor in the course of their normal operations. The data collection phase of this evaluation began July 15, 1979, and will continue until July 15, 1980. (Author)

The purpose of this report is to evaluate pilot capability to fly air traffic control offsets and vertical profiles for both two- and three-dimensional area navigation (RNAV) modes both with and without the use of a flight director. Flight pilot subjects participated in simulation tests conducted at the National aviation facilities Experimental Center. Performance was measured for two varibles: total system crosstrack error (TSCT) and flight technical error (FTE); and assessment was made of pilot performance on horizontal tracking, vertical tracking, and turns. The major findings were: (1) 2-sigma and 2-RMS steady state tracking data for centerline and offset tracking were within + or - 1.5 nautical miles of the course being flown, (2) summary data for centerline turns never exceeded a + or - 2 nautical miles error range, (3) centerline tracking was less variable than offset tracking, (4) the use of 3D RNAV mode to arrive at a specified altitude at a specific location increased pilot workload along the route segment leading to that location, (5) lag times for pilot response to ATC RNAV clearances were found to be a function of the situation complexity, and (6) the calculated RSS statistic proved to be an overconservative estimator of TSCT errors. (Author)

This Phase III report is the last of a series of interim and data reports dealing with offsets and turn anticipation techniques using a single Waypoint analog RNAV system and a noncentered needle CDI instrument. Eight instrument rated pilots participated in a series of flight simulation tests employing solo pilot techniques which were conducted at the National Aviation Facilities Experimental Center (NAFEC) in order to measure total system crosstrack (TSCT) and flight technical error (FTE) as well as operational pilot performance. The tests were designed to assess pilot performance for: (1) anticipation of turns while maintaining a desired offset, and (2) steady state parallel offset tracking proficiency. Performance was measured on these variables: horizontal tracking, airspeed control and procedural performance. The horizontal tracking data included both steady state (parallel offset) and transition (parallel offset) data. The major findings of this study were: (1) No significant differences exist between the offset turn data and the offset steady state data in terms of TSCT or FTE magnitude; and (2) the procedures used for shallow angle turns (29 deg and 48 deg) and the logic for the interception of the final approach course have a potential for blunders. (Author)

A four-part dynamic simulation using two systems of navigation, area navigation (RNAV) and very high frequency omnidirectional radio range (VOR), was conducted using the Digital Simulation Facility (DSF) at the National Aviation Facilities Experimental Center (NAFEC). The objectives were to: (1) validate the results derived from fast-time simulation tests of RNAV and Jet-VOR route structures through real-time simulation tests, (2) determine whether benefits resulted from the application of RNAV in the high-altitude enroute environment, and (3) establish the impact that the number of potential aircraft conflict situations has on the ATC system and system user. Simulations were conducted in a fast-time mode, without controller intervention, for an area encompassed by five high-altitude Chicago Air Route Traffic Control Center (ARTCC) sectors and for a single selected sector of the five. Real-time simulations, with controller intervention, were conducted for both the five- and one-sector configurations.

Six pilots participated in a series of flight simulation tests employing solo pilot techniques which were conducted at the National Aviation Facilities Experimental Center (NAFEC) in the cockpit Simulation Facility in order to measure Total System Crosstrack (TSCT) and Flight Technical Error (FTE) using a multiple waypoint storage 2D/3D area navigation (RNAV) system. The tests were designed to assess pilot performance as a function of the interexperimental variables: (1) 2D RNAV mode versus 3D RNAV mode, (2) flight director versus no flight director, (3) insertion of an impromptu waypoint into a previously entered flight plan, and (4) different route structures. Performance was measured on the variables: horizontal tracking, vertical tracking, airspeed control, and procedural performance. Major findings include less TSCT error in the 2D mode, improved tracking accuracy using the flight director, and FTE consistently less than the amount budgeted in AC-90-45A. No statistically significant differences were found for the impromptu waypoint entry; however, one-third of the impromptus resulted in either blunders or procedural errors (including wrong information entered or large overshoots at the waypoint prior to the impromptu segments).

This volume presents the detailed support data for the 4D time control and localizer software definitions. Program listings for the final design are also presented. (Author)

This report summarizes the results of a study to design, develop, and implement a 3D/4D Area Navigation System for increasing aviation system capacity in the terminal area. Varying degrees of ATC and airborne system capability were assumed. The concepts developed are compatible with mixed airborne equipment capabilities. The 3D terminal area procedures should result in reduced ATC communications through the use of 3D STAR's for nominal profile definition. Reverse fans and base offsets are used for impromptu path modifications. Increased safety should result by maintaining navigation in the cockpit. The 4D procedures rely on a computer aided ATC metering and spacing system. The use of RNAV STAR's is expected to substantially improve the M and S algorithm development, controller interface design, and pilot tracking accuracies. The final avionics design has the capability for emulating two types of avionics equipments: one representing a minimum capability leg-at-a time, station referenced RNAV system and one representing a sophisticated route oriented, geographic referenced RNAV system. Real time cockpit simulations were performed to determine the adequacy of the pilot interface design and the performance capability. The system has been delivered to the FAA for actual flight testing. (Author)

This report presents the results of a study to determine if a requirement exists for reduced route widths in the National Airspace System. The basis for this investigation was the recommendation by the FAA/Industry RNAV Task Force that provision be made for constant and reduced route widths in order to handle the anticipated growth in air traffic by allowing more routes in the same airspace and less restriction on application of parallel offsets. The recommendation included a reduction of high altitude route widths from + or - 4.0 nm in the 1977-1982 period to + or - 2.5 nm in the post-1982 period. Route width requirements for both high altitude enroute and terminal areas are quantified, based on the impact of route width on route efficiency, airspace capacity, and route length. Results of this study, which are based on analysis of specific, high traffic demand geographical areas, indicate that there is a requirement to eliminate the current splayed route widths and provide constant width routes, but that there is no requirement for reduction of route widths below a constant + or - 4 nm in the high altitude enroute structure, or below the + or -2 nm or + or -4 nm, dependent upon distance from the VORTAC, which are currently required in the terminal area. (Author)

A dynamic simulation using the digital simulation facility at the National Aviation Facilities Experimental Center (NAFEC), Atlantic City, New Jersey, was conducted to determine the effects of the air traffic control (ATC) system and the system users derivable from the use of area navigation (RNAV) and area navigation with vertical guidance (VNAV) in a high-density terminal area. The John F. Kennedy Airport airspace was configured with an RNAV/VNAV route system to provide the test bed for the study. The study analyzed selected controller workload and system performance measures for various mixtures of RNAV, VNAV, and radar-vectored operations. Results show that controllers can use RNAV/VNAV maneuvers in the control of traffic in lieu of radar vector techniques and that controller workload decreased as the level of RNAV/VNAV participation increased. Controller acceptance of RNAV/VNAV principles and techniques in the ATC terminal area increased as familiarity and experience with RNAV/VNAV were gained. Controllers favored the use of RNAV over a pure radar-vector environment, expressing the opinion that RNAV could provide benefits to both controller and system user. Significant decreases in controller communications workload and slight increases in operations were recorded as the percentages of RNAV/VNAV aircraft in the system were increased. In general, the orderliness of the ATC system improved as the percentage of RNAV/VNAV aircraft was increased. Input from two general aviation trainers (GAT's) was integrated with the targets from the digital simulation facility.

This document presents the results of a three year study effort to define the cost and operational impact, and to assess the economic benefits which are expected to accrue to the ACT system and various users of the National Airspace System as a result of the implementation of Area Navigation. Previous impact analyses are expanded to include the primary aspects of ATC system operation and to include a broad spectrum of user groups, route structure, and types of operation. System impact results are presented pertaining to slant range effects, VORTAC requirements, ATC automation, airspace capacity, route development, charting, flight inspection, VNAV, controller training, and controller productivity. User impact results are presented in terms of fuel and time increment benefits for several classes of users, comparing 2D RNAV to VOR in the high and low altitude structures, and comparing 2D, 3D, and 4D RNAV to VOR/radar vectors in the terminal area. Estimates are made of total annual savings due to RNAV, and an analysis of user equipment cost versus benefits is presented. The results of the user and system impact analyses, together with results of related system studies in the areas of avionics standards, waypoint standards, route designs, and flight technical error are utilized to develop an RNAV operational concept. The system design and implementation concepts presented are based on the Task Force concept, but modified as appropriate to insure maximum benefits to the ATC system and a broad spectrum of users of the National Airspace system. (Author)

This is the final report of a simulator experiment in which 45 highly experienced pilots made five three-dimensional terminal area navigation flights each on a different parallel course offset. The experiment was designed to assess pilot performance as a function of three turn anticipation techniques (Procedural, Computed, and Electronic Map Display) and three levels of waypoint storage capacity (one, two, and three) on four different parallel course offsets (three and five miles left and right) and centerline. The flight task included SID, STAR, and approach procedures in the simulated Atlantic City area. Performance was measured on four variables: horizontal and vertical tracking, airspeed control, and procedural performance.

Topics include requirements and specifications, radio techniques, non-radio techniques, appropriate navigation system components, and total system considerations., NATO furnished. Presented at the AGARD Avionics Panel Technical Meeting held in Sandefjord, Norway, on 8-12 September 1975.

Flight test data gathered during a series of RNAV flight tests at the National Aviation Facilities Experimental Center (NAFEC) in Atlantic City, New Jersey, are presented. The report concentrates on the radio navigation sensor errors and the resulting errors in position determination that are inherent in area navigation (RNAV) operation in the terminal area. Statistical data as well as distributions of the errors are presented. One-standard deviations of 1.5 degrees for very high frequency omnidirectional radio range (VOR) and 0.094 nautical mile for distance measuring equipment (DME) were computed from the flight test data. These statistics represent combined ground and airborne sensor errors.

A high-altitude area navigation (RNAV) network study was conducted at the National Aviation Facilities Experimental Center (NAFEC) in order to (1) apply and evaluate the FAA/Industry RNAV Task Force concepts for RNAV route structures in the high-altitude airspace, (2) offer alternative approaches, where appropriate, and (3) derive data relative to the potential benefits to the air traffic control (ATC) system and to its users by the implementation of RNAV. For design purposes, the enroute structure was based on the requirements for an all-RNAV high-altitude environment starting in 1977. Route structures were evaluated through fast time simulation of a mixed RNAV/VOR environment, with traffic samples representing projected traffic densities for the pre-1977, 1977-1982, and post-1982 time periods with varying mixes of RNAV-equipped aircraft. Alternative route structure design principles were developed which differed from the RNAV Task Force concepts in (1) the configuration of arrival and departure routing into and out of terminal areas, (2) the use of one-way routes, (3) the use of charted routes versus provision for noncharted offset tracks, (4) the treatment given to traffic from intermediate terminals with respect to nearby flows between more distant terminals, and (5) route width requirements.

The objectives of this program were to evaluate the Digital Data Broadcast (DDB) system in the following areas: (1) Substantiate a predicted reduction in cockpit workload and pilot blunder provided by the addition of broadcast data into the RNAV environment. (2) Assess the technical performance characteristics and overall feasibility of a DDB Engineering Model hardware unit. (3) Determine the operational utilization of the DDB concept for RNAV in the terminal area. The results of program were: (1) The results of the DDB Flight Test program indicate a positive reduction in cockpit workload and pilot blunder through the utilization of the DDB concept in the RNAV environment system. (2) The DDB concept was satisfactorily proved by the utilization of the DDB Engineering Model hardware. Specific areas of recommended improvement are modifications to X-mode DDB pulse spacing and to waypoint designators. (3) The operational utilization of the DDB concept permits its user to devote more time to cockpit management duties, since it reduces the required RNAV navigation input times and thereby, reduces cockpit workload. (Author), Prepared in cooperation with Champlain Technology Industries.

This document summarizes the results of a three-dimensional area navigation flight test. Horizontal error parameters evaluated included navigation sensor (VOR/DME) error, flight technical error, computer and total system error. Vertical error parameters evaluated included altimetry error, flight technical error, vertical error due to along track error, computer error, and total system error. Three vertical profiles were flown in a six segment test route; three-degree climbs, three degree descents, and a six degree descent. Statistical evaluations were performed on the data and resulting values were then compared to FAA Advisory Circular 90-45A values. Statistical envelope plots for each segment and error type were generated as aids in evaluating the data. Tabular listings, by flight segment, are provided for each error type, as well as route summaries.

A series of fast time simulations of high altitude route structures were conducted as a part of the FAA Area Navigation Engineering and Development Program Plan. This report presents the results of these simulations and supersedes the Preliminary Fast Time Simulation Results Report dated August, 1974. System/user payoff conclusions are presented based on the results of the simulations and observations by the author. While the limitations of fast time simulation resulting from the lack of controller intervention effects are recognized, the simulation techniques employed provide, as a minimum, a substantial basis for the identification of well marked trends and a sizeable data base upon which a reasonable degree of confidence can be placed., See also report dated Sep 74, AD-787 432.

The document was prepared to develop a specific waypoint designator format and to provide recommended waypoint location and identification standards. The primary objective of this program was to evaluate the impact of the Task Force concepts on waypoint designation techniques and standards. The satisfaction of this objective was accomplished by thoroughly investigating the alternative techniques for waypoint identification and communication for both charted and impromptu operations. It was necessary to review, analyze and evaluate fourteen proposed waypoint designation techniques in the course of this investigation. The ultimate choice of a waypoint designator had to include provisions for three phases of RNAV implementation with a varying mix of charted and preplanned direct routes. Second, the waypoint designator format had to be compatible with a wide range of airborne area navigation equipment, as well as, with pilot/controller communication practices . Finally, the waypoint designator technique has to accommodate diverse user applications covering the spectrum of general aviation, business and airline applications.

The results of analytical study and real time cockpit simulation of three and four dimensional airborne area navigation concepts for increasing aviation system capacity in the terminal area are presented in this report. Varying degrees of ATC capability, approach and landing aids, and airborne system capability are addressed. Analytical results present the airborne/ATC equipment accuracies necessary to support varying degrees of control precision. Results from the real time cockpit simulation indicate the degree of ATC/pilot and pilot/airborne equipment interaction necessary to obtain the time delivery precision predicted by the analytical results. All the airborne concepts rely on a high level ATC metering and spacing system. As a result airborne system complexity for each user type is held to a minimum and simultaneous ATC control of aircraft with mixed equipment capabilities can be accomplished.