Thomas Prevot

Human-In-the-Loop Evaluation of NextGen Concepts in the Airspace Operations Laboratory

The Airspace Operations Laboratory (AOL) at the NASA Ames Research Center hosts a powerful simulation environment for human-in-the-loop studies of air traffic operations. The primary real-time simulation capabilities are developed by the AOL development team as part of the Multi Aircraft Control System (MACS) and cover a wide range of operational environments from current day operations to future operational concepts like those envisioned for the Next Generation Air Transportation System (NextGen). The research focus in the AOL is on examining air traffic control and traffic management operations across multiple air traffic control sectors and Centers in rich air/ground environments that can include oceanic, enroute and terminal airspace. The basic simulation capabilities and earlier research was presented at the AIAA Modeling and Simulation Technologies conference in 2006. Since then, the AOL capabilities have been continuously improved and expanded. Over the past four years the AOL has been extensively utilized to investigate a variety of NextGen concepts for NASA’s NextGen Airspace Program and the FAA’s Air Traffic Organization for Planning, Research and Technology. The primary focus areas under investigation in the AOL are Separation Assurance and the associated Functional Allocation for NextGen, Controller Managed Spacing for nearto mid-term Terminal area operations, flow-based trajectory management and multi-sector planning and dynamic airspace configuration and flexible airspace management. This paper first gives an overview over the most significant capabilities that were added since 2006 and then reviews at a high level the main activities and findings in the different research focus areas.

Human-in-the-Loop Evaluation of Ground-Based Automated Separation Assurance for NextGen

This paper describes human-in-the-loop research at NASA Ames Research Center on service provider-based automated separation assurance for the Next Generation Air Transportation System (NextGen). Key human/automation integration aspects such as levels of automation and roles and responsibilities of automated separation management are investigated in the Airspace Operations Laboratory. A trilogy of part-task studies was designed to examine efficiency, safety, workload impact and acceptability of central aspects of the concept. Findings from a 2007 study on strategic trajectory-based automated separation assurance with data link-equipped aircraft are discussed in detail. Preliminary results on mixed operations with data link and conventional aircraft gathered in spring 2008 are included. The experiment design for investigating tactical safety assurance and off-nominal situations in summer 2008 is outlined. This research was funded by the Separation Assurance element of NASA’s Next Generation Air Transportation System – Airspace Project.

The Airspace Operations Laboratory (AOL) at NASA Ames Research Center

The Airspace Operations Laboratory (AOL) at NASA Ames Research Center hosts a powerful simulation environment for human-in-the-loop studies of air traffic operations. The capabilities have been developed at NASA Ames and cover a wide range of operational environments from current day operations to future operational concepts like those envisioned for the Next Generation Air Transportation System (NGATS). The research focus in the AOL is on examining air traffic control and management operations across multiple air traffic control sectors in rich air/ground environments that can include oceanic, enroute and terminal airspace. Past research involving the AOL includes distributed air/ground traffic management studies on trajectory negotiation, airborne self-separation and airborne spacing. Ongoing research with various government and industry partners include trajectory-oriented operations with limited delegation; multi sector planning; the US tailored arrivals initiative; airline-based sequencing and spacing, and airborne merging and spacing. In the future we expect using the AOL extensively for early exploration of operational questions crucial to the NGATS, like human-automation interaction, roles and responsibilities in distributed environments and required automation capabilities. This paper first gives an overview over philosophy, physical layout, software and connectivity of the AOL. Next, the available real-time capabilities are described in detail followed by a description of some important offline capabilities. The paper concludes with a summary of past and present research in the AOL and concluding remarks.

MACS: A Simulation Platform for Today's and Tomorrow's Air Traffic Operations

This paper describes the Multi Aircraft Control System (MACS) simulation platform developed in the Airspace Operations Laboratory (AOL) at NASA Ames Research Center. MACS is a comprehensive research tool that has been developed to increase the overall realism and flexibility of controller- and pilot-in-the loop air traffic simulations. The research focus in the AOL is on examining air traffic operations in rich air/ground environments that can include multiple oceanic, en route, and terminal airspace sectors. The AOL research and development team maintains and continuously expands the capabilities of MACS to rapidly prototype new interfaces, displays, tools and operational concepts for addressing the complex controller/pilot/automation integration crucial to the implementation of the Next Generation Air Transportation System (NextGen). Sample applications of the MACS software are presented to show the range of air traffic environments that can be investigated. Funding for this work was provided by NASA’s Aeronautics Research Mission Directorate (ARMD) and NGATS Airspace Systems research program.

Comparison of Ground-Based and Airborne Function Allocation Concepts for NextGen Using Human-In-The-Loop Simulations

Investigation of function allocation for the Next Generation Air Transportation System is being conducted by the National Aeronautics and Space Administration (NASA). To provide insight on comparability of different function allocations for separation assurance, two human-in-the-loop simulation experiments were conducted on homogeneous airborne and ground-based approaches to four-dimensional trajectory-based operations, one referred to as ground-based automated separation assurance (groundbased) and the other as airborne trajectory management with self-separation (airborne). In the coordinated simulations at NASA s Ames and Langley Research Centers, controllers for the ground-based concept at Ames and pilots for the airborne concept at Langley managed the same traffic scenarios using the two different concepts. The common scenarios represented a significant increase in airspace demand over current operations. Using common independent variables, the simulations varied traffic density, scheduling constraints, and the timing of trajectory change events. Common metrics were collected to enable a comparison of relevant results. Where comparisons were possible, no substantial differences in performance or operator acceptability were observed. Mean schedule conformance and flight path deviation were considered adequate for both approaches. Conflict detection warning times and resolution times were mostly adequate, but certain conflict situations were detected too late to be resolved in a timely manner. This led to some situations in which safety was compromised and/or workload was rated as being unacceptable in both experiments. Operators acknowledged these issues in their responses and ratings but gave generally positive assessments of the respective concept and operations they experienced. Future studies will evaluate technical improvements and procedural enhancements to achieve the required level of safety and acceptability and will investigate the integration of airborne and ground-based capabilities within the same airspace to leverage the benefits of each concept.

A MULTI-FIDELITY SIMULATION ENVIRONMENT FOR HUMAN-IN-THE-LOOP STUDIES OF DISTRIBUTED AIR GROUND TRAFFIC MANAGEMENT

This paper describes a Distributed Air Ground Traffic Management (DAG-TM) simulation environment created at NASA Ames Research Center for conducting human-in-the-loop evaluations of new concepts for managing and controlling air traffic. The simulation environment combines high fidelity full mission flight simulators with mid-fidelity air traffic controller/manager workstations as well as low to mid-fidelity desktop workstations for additional pilots, controllers, experiment managers and observers. The simulation is distributed amongst different facilities and laboratories at Ames and provides for connecting multiple off-site simulators via the Internet. The Crew Activity Tracking System (CATS) can be attached for real-time tracking and analysis of pilot and controller activities, and intelligent agents can supplant ancillary human participants.

Trajectory-Oriented Operations with Limited Delegation: An Evolutionary Path to NAS Modernization

*† ‡ § ** †† This paper presents a concept named Trajectory Oriented Operations with Limited Delegation. The concept provides a framework for transforming NAS operations in line with global modernization trends. It enables the evolutionary introduction of trajectory oriented air traffic tools and airborne separation assistance systems. Specific implementation examples for several evolutionary phases are presented. The tools and procedures prototyping this concept will be further developed and tested in simulations at NASA Ames Research Center as part of the NextNAS project.

A Human -in -the -Loop Evaluation of Air -Ground Trajectory Negotiation

An integrated air ground simulation with commercial airline pilots a nd certified professional controllers was conducted at NASA Ames Research Center to evaluate a concept for air -ground trajectory negotiation. This concept was developed as part of the Distributed Air -Ground Trajectory Negotiation Project, which explores us e of new technology, including CPDLC and flight deck and ATC decision support tools, to accommodate user preferred trajectories. Two human -in -the -loop simulation studies were conducted in 2002 and 2003. The first study in 2002 focused on how an integration of air and ground side decision support tools (DSTs) with data link can potentially improve efficiency, capacity, and workload distribution. The second study in 2003 focused on pilot/controller interactions during a trajectory negotiation. The results fro m the 2002 study suggested that this concept allowed for more precise delivery, efficient flight paths, and lower controller workload, while the 2003 study demonstrated the feasibility of trajectory negotiation via data link. This paper summarizes these re sults, discusses critical factors that contribute to the success of the concept, and open issues that need to be understood in order to further the concept. Overall, integration of DSTs and data link seems to show great potential. The trajectory negotiatio n concept appears feasible but its potential for benefits needs further research.

ATC Technologies for Controller-Managed and Autonomous Flight Operations

*† ‡ § This paper describes the ground-side automation prototyped in the Airspace Operations Laboratory (AOL) at NASA Ames Research Center in support of two concepts related to Distributed Air Ground Traffic Management (DAG-TM) operations: Trajectory-based air traffic control (ATC) and Mixed operations with airborne self separation. The paper presents the design of the ATC automation and the evaluation of both concepts in large scale simulations. Advanced ATC automation was integrated into an emulation of state-of-the-art en route controller displays. The design of automation and controller tools for managing trajectories of data link equipped aircraft is the result of many years of air/ground integration research. The toolset includes highly responsive graphical trajectory planning and conflict probing functions, interactive timelines for aircraft scheduling, speed advisory functions and delay feedback indications for arrival metering. The automation is fully integrated with data link. To support mixed operations additional tasks had to be automated. Even though flight crews of “autonomous” aircraft are responsible for separating their airplane from all other traffic, a complex set of ground-based automation has to take over a number of additional services for autonomous aircraft that controllers and traffic managers otherwise provide for managed aircraft. The first part of the paper describes the design rationale for the ground-based automation in the context of current air traffic modernization trends. A detailed description of the prototyped ATC technologies is provided in the appendix. The second part of the paper presents the ground-side perspective of each of the concepts effectiveness in terms of capacity, controller workload, safety, efficiency, and controller acceptability. Simulation studies using the trajectory-based ATC managed operations have demonstrated that controllers were able to manage separation and arrival times above current day traffic volumes by trajectory adjustments alone, without significantly changing roles and responsibilities of pilots and controllers. A joint Ames/Langley simulation of mixed operations shows a significant potential for much higher capacity gains. However, a number of safety concerns would need to be addressed before airborne self-separation could be operationally implemented in high density mixed environments. DAG-TM results indicate that trajectory-based ATC with integrated ground-side DSTs and airborne FMSs can safely increase capacity in the near to medium-term and could provide the environment required to enable concepts like airborne self-separation. DAG-TM research was funded by the Airspace Systems program as part of the Advanced Air Transportation Technologies project. DAG-TM activities were conducted by NASA Ames, NASA Langley, and NASA Glen Research Centers.

AIR TRAFFIC CONCEPT UTILIZING 4D TRAJECTORIES AND AIRBORNE SEPARATION ASSISTANCE

Funding for this work was provided by the Advanced Air Transportation Technologies (AATT) project office of NASAs Airspace Systems Program. This paper presents a concept – with the potential for increasing airspace system-wide efficiency and safety – which combines strategic, 4-D userpreferred trajectories with tactical, Airborne Separation Assistance Systems (ASAS). First, prior research and concepts for improving air traffic management are reviewed. Second, the concept for integrating trajectory-orientation and airborne separation assistance is described. Using an example traffic scenario, we then examine how the conflicts might be resolved using A) current day tactical operations, B) current day tactical operations with airborne separation assistance added, and C) a pure trajectory-oriented approach.