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At least 253 records · Page 14

A piloted simulator investigation of stability and control, display and crew-loading requirements for helicopter instrument approach. Part 1: Technical discussion and results

A ground-simulation experiment was conducted to investigate the influence and interaction of flight-control system, fight-director display, and crew-loading situation on helicopter flying qualities during terminal area operations in instrument conditions. The experiment was conducted on the Flight Simulator for Advanced Aircraft at Ames Research Center. Six levels of control complexity, ranging from angular rate damping to velocity augmented longitudinal and vertical axes, were implemented on a representative helicopter model. The six levels of augmentation were examined with display variations consisting of raw elevation and azimuth data only, and of raw data plus one-, two-, and three-cue flight directors. Crew-loading situations simulated for the control-display combinations were dual-pilot operation (representative auxiliary tasks of navigation, communications, and decision-making). Four pilots performed a total of 150 evaluations of combinations of these parameters for a representative microwave landing system (MLS) approach task.

Lebacqz, J. V.↗

Control and display requirements for decelerating approach and landing of fixed- and rotary-wing VSTOL aircraft

This paper reviews the results of several simulation investigations of rotary-wing and fixed-wing VSTOL aircraft performing terminal-area operations that include decelerating approaches under instrument conditions and recovery to either fixed landing pads or a ship. By concentrating on instrument decelerating approaches and the hover and landing, it is possible to compare directly the control and display requirements for similar tasks for aircraft with and without vectored thrust capability. Collectively, the results from these experiments, together with other simulator and flight experiments and operational experience, provide a consistent view of control and display complexity required for similar operational capability in adverse weather for the two types of VSTOL configurations. Some initial data showing influence of the transition corridor on flying qualities during transition are pesented and lead to a general discussion of the problem of operating margin definition.

Lebacqz, J. V.↗

Quiet Short-Haul Research Aircraft - A summary of flight research since 1981

The Quiet Short-Haul Research Aircraft (QSRA), designed for flight investigation into powered-lift terminal area operations, first flew in 1978 and has flown 600 hours since. This report summarizes QSRA research since 1981. Numerous aerodynamic flight experiments have been conducted including research with an advanced concept stability and control augmentation and pilot display system for category III instrument landings. An electromechanical actuator system was flown to assess performance and reliability. A second ground-based test was conducted to further evaluate circulation-control-wing/upper-surface-blowing performance. QSRA technology has been transferred through reports, guest pilot evaluations and airshow participation. QSRA future research thoughts and an extensive report bibliography are also presented.

Riddle, Dennis W.↗

Master/Programmable-Slave Computer

Unique modular computer features compactness, low power, mass storage of data, multiprocessing, and choice of various input/output modes. Master processor communicates with user via usual keyboard and video display terminal. Coordinates operations of as many as 24 slave processors, each dedicated to different experiment. Each slave circuit card includes slave microprocessor and assortment of input/output circuits for communication with external equipment, with master processor, and with other slave processors. Adaptable to industrial process control with selectable degrees of automatic control, automatic and/or manual monitoring, and manual intervention.

Smaistrla, David↗

Current and planned use of the Navstar Global Positioning System by NASA

NASA was quick to realize the potential that the Global Positioning System (GPS) had to offer for its many diverse vehicles, experiments and platforms. Soon after the first Block 1 GPS satellites were launched, NASA began to use the tremendous capabilities that they had to offer. Even with a partial GPS constellation in place, important results have been obtained about the shape, orientation and rotation of the earth and calibration of the ionosphere and troposphere. These calibrations enhance geophysical science and facilitate the navigation of interplanetary spacecraft. Some very important results have been obtained in the continuing NASA program for aircraft terminal area operations. Currently, a large amount of activity is being concentrated on real time kinematic carrier phase tracking which has the potential to revolutionize aircraft navigation. This year marks the launch of the first GPS receiver equipped earth-orbiting NASA spacecraft: the Extreme Ultraviolet Explorer and the Ocean Topography Experiment (TOPEX/Poseidon). This paper describes a cross section of GPS-based research at NASA.

Theiss, Harold L.↗

Advanced Air Traffic Management Research (Human Factors and Automation): NASA Research Initiatives in Human-Centered Automation Design in Airspace Management

NASA has initiated a significant thrust of research and development focused on providing the flight crew and air traffic managers automation aids to increase capacity in en route and terminal area operations through the use of flexible, more fuel-efficient routing, while improving the level of safety in commercial carrier operations. In that system development, definition of cognitive requirements for integrated multi-operator dynamic aiding systems is fundamental. The core processes of control and the distribution of decision making in that control are undergoing extensive analysis. From our perspective, the human operators and the procedures by which they interact are the fundamental determinants of the safe, efficient, and flexible operation of the system. In that perspective, we have begun to explore what our experience has taught will be the most challenging aspects of designing and integrating human-centered automation in the advanced system. We have performed a full mission simulation looking at the role shift to self-separation on board the aircraft with the rules of the air guiding behavior and the provision of a cockpit display of traffic information and an on-board traffic alert system that seamlessly integrates into the TCAS operations. We have performed and initial investigation of the operational impact of "Dynamic Density" metrics on controller relinquishing and reestablishing full separation authority. (We follow the assumption that responsibility at all times resides with the controller.) This presentation will describe those efforts as well as describe the process by which we will guide the development of error tolerant systems that are sensitive to shifts in operator work load levels and dynamic shifts in the operating point of air traffic management.

Corker, Kevin M.↗

An Introduction to Rotorcraft Research at NASA Ames

NASA Ames Research Center, Moffett Field, CA is the NASA lead Center for rotorcraft research. Rotorcraft research at Ames includes system analysis and configuration optimization, aeromechanics, and flight control and cockpit integration. Research in other areas such as composite structure and material, and rotor acoustics are conducted mainly at Langley Research Center, and rotorcraft propulsion and drivetrain are conducted at Lewis Research Center. This seminar will discuss Ames' rotorcraft research goals and some sample research projects and results. The talk will also briefly describe the newly fanned Army/NASA Rotorcraft Division, which combines the resources of rotorcraft branches in NASA Ames Aeronautics Directorate with Army's Aeroflightdynamics Directorate to better achieve the missions of the two previous rotorcraft research organizations at Ames. Rotorcraft research activities at NASA Ames are funded by two main program categories: Research and Technology (RUTH Base program and the Short Haul (Civil Tiltrotor) program. Work in the R&T program is carried out by the research staff in the Army/NASA Rotorcraft Division, and the work on SH(CT) program is carried out jointly by the SH(CT) program office and the Army/NASA Rotorcraft Division. Sample research projects and results in REST base program, such as conceptual assessment of several high-speed rotorcraft, rotorcraft CFD, individual blade control for reduction of external noise and vibration, noise-abatement flight procedures, engine inoperative procedures, handling qualities, and advanced flight control laws are broadly reviewed. High-speed rotorcraft research related to SH(CT) technology development conducted at Ames in the areas of low-noise proprotor, and low-noise terminal-area operations is also discussed.

Chen, Robert T. N.↗

A Cognitive System Model for Human/Automation Dynamics in Airspace Management

NASA has initiated a significant thrust of research and development focused on providing the flight crew and air traffic managers automation aids to increase capacity in en route and terminal area operations through the use of flexible, more fuel-efficient routing, while improving the level of safety in commercial carrier operations. In that system development, definition of cognitive requirements for integrated multi-operator dynamic aiding systems is fundamental. In order to support that cognitive function definition, we have extended the Man Machine Integrated Design and Analysis System (MIDAS) to include representation of multiple cognitive agents (both human operators and intelligent aiding systems) operating aircraft, airline operations centers and air traffic control centers in the evolving airspace. The demands of this application require representation of many intelligent agents sharing world-models, and coordinating action/intention with cooperative scheduling of goals and actions in a potentially unpredictable world of operations. The MIDAS operator models have undergone significant development in order to understand the requirements for operator aiding and the impact of that aiding in the complex nondeterminate system of national airspace operations. The operator model's structure has been modified to include attention functions, action priority, and situation assessment. The cognitive function model has been expanded to include working memory operations including retrieval from long-term store, interference, visual-motor and verbal articulatory loop functions, and time-based losses. The operator's activity structures have been developed to include prioritization and interruption of multiple parallel activities among multiple operators, to provide for anticipation (knowledge of the intention and action of remote operators), and to respond to failures of the system and other operators in the system in situation-specific paradigms. The model's internal representation has been be modified so that multiple, autonomous sets of equipment will function in a scenario as the single equipment sets do now. In order to support the analysis requirements with multiple items of equipment, it is necessary for equipment to access the state of other equipment objects at initialization time (a radar object may need to access the position and speed of aircraft in its area, for example), and as a function of perception and sensor system interaction. The model has been improved to include multiple world-states as a function of equipment am operator interaction. The model has been used -1o predict the impact of warning and alert zones in aircraft operation, and, more critic-ally, the interaction of flight-deck based warning mechanisms and air traffic controller action in response to ground-based conflict prediction and alerting systems. In this operation, two operating systems provide alerting to two autonomous, but linked sets of operators, whose view of the system and whose dynamics in response are radically different. System stability and operator action was predicted using the MIDAS model.

Corker, Kevin M.↗

A Tool for Low Noise Procedures Design and Community Noise Impact Assessment: The Rotorcraft Noise Model (RNM)

To improve aircraft noise impact modeling capabilities and to provide a tool to aid in the development of low noise terminal area operations for rotorcraft and tiltrotors, the Rotorcraft Noise Model (RNM) was developed by the NASA Langley Research Center and Wyle Laboratories. RNM is a simulation program that predicts how sound will propagate through the atmosphere and accumulate at receiver locations located on flat ground or varying terrain, for single and multiple vehicle flight operations. At the core of RNM are the vehicle noise sources, input as sound hemispheres. As the vehicle "flies" along its prescribed flight trajectory, the source sound propagation is simulated and accumulated at the receiver locations (single points of interest or multiple grid points) in a systematic time-based manner. These sound signals at the receiver locations may then be analyzed to obtain single event footprints, integrated noise contours, time histories, or numerous other features. RNM may also be used to generate spectral time history data over a ground mesh for the creation of single event sound animation videos. Acoustic properties of the noise source(s) are defined in terms of sound hemispheres that may be obtained from theoretical predictions, wind tunnel experimental results, flight test measurements, or a combination of the three. The sound hemispheres may contain broadband data (source levels as a function of one-third octave band) and pure-tone data (in the form of specific frequency sound pressure levels and phase). A PC executable version of RNM is publicly available and has been adopted by a number of organizations for Environmental Impact Assessment studies of rotorcraft noise. This paper provides a review of the required input data, the theoretical framework of RNM's propagation model and the output results. Code validation results are provided from a NATO helicopter noise flight test as well as a tiltrotor flight test program that used the RNM as a tool to aid in the development of low noise approach profiles.

Conner, David A.↗

NASA Subsonic Rotary Wing Project

This slide presentation will outline the rationale for, and the initial results of, a contractor study being performed by a SAIC-led team of Bell Helicopter Textron, Sensis, and Optimal Synthesis. Together, this team represents an extensive body of subject matter expertise as related to rotorcraft technologies and design, airspace demand modeling simulation, and terminal area operations and flight path planning. The initial conceptual design results of a fleet of civil tiltrotor aircraft ranging in size from 10 to 120 passengers is a key highlight of the work to be presented. The intent of this presentation is to begin to provide the general community of rotorcraft researchers, manufacturers, and end-users an appreciation of the criticality of interjecting rotorcraft-specific technology and concepts of operation issues into Next Gen airspace requirements

Young, Larry A.↗

The Impact of Data Communications Messages in the Terminal Area on Flight Crew Workload and Eye Scanning

This paper, to accompany a discussion panel, describes a collaborative FAA and NASA research study to determine the effect Data Communications (Data Comm) messages have on flight crew workload and eye scanning behavior in busy terminal area operations. In the Next Generation Air Transportation System Concept of Operations, for the period 2017-2022, the FAA envisions Data Comm between controllers and the flight crew to become the primary means of communicating non-time critical information. Four research conditions were defined that span current day to future equipage levels (Voice with Paper map, Data Comm with Paper map, Data Comm with Moving Map Display with ownship position displayed, Data Comm with Moving Map, ownship and taxi route displayed), and were used to create arrival and departure scenarios at Boston Logan Airport. Preliminary results for workload, situation awareness, and pilot head-up time are presented here. Questionnaire data indicated that pilot acceptability, workload, and situation awareness ratings were favorable for all of the conditions tested. Pilots did indicate that there were times during final approach and landing when they would prefer not to hear the message chime, and would not be able to make a quick response due to high priority tasks in the cockpit.

Comstock, James R., Jr.↗

Observing Campaign for Potential Deep Impact Flyby Target 163249 (2002 GT)

The Deep Impact spacecraft is currently on course for a Jan. 4, 2020 flyby of the sub-kilometer near-Earth asteroid 163249 (2002 GT). The re-targeting will be complete with a final small maneuver scheduled for Oct. 4, 2012. 2002 GT, which is also designated as a Potentially Hazardous Asteroid (PHA), has a well-determined orbit and is approx 800 m in diameter (H=18.3). Little more is known about the nature of this object, but in mid-2013 it will pass near the Earth, affording an exceptional opportunity for ground-based characterization. At this apparition 2002 GT will be in range of Arecibo. In addition to Doppler measurements, radar delay observations with precisions of a few microseconds are expected and have a good chance of revealing whether the system is binary or not. The asteroid will be brighter than 16th mag., which will facilitate a host of observations at a variety of wavelengths. Light curve measurements across a wide range of viewing perspectives will reveal the rotation rate and ultimately lead to strong constraints on the shape and pole orientation. Visible and infrared spectra will constrain the mineralogy, taxonomy, albedo and size. Along with the radar observations, optical astrometry will further constrain the orbit, both to facilitate terminal guidance operations and to potentially reveal nongravitational forces acting on the asteroid. Coordinating all of these observations will be a significant task and we encourage interested observers to collaborate in this effort. The 2013 apparition of 2002 GT represents a unique opportunity to characterize a potential flyby target, which will aid interpretation of the high-resolution flyby imagery and aid planning and development of the flyby imaging sequence. The knowledge gained from this flyby will be highly relevant to the human exploration program at NASA, which desires more information on the physical characteristics of sub-kilometer near-Earth asteroids.

Pittichova, Jana↗

Preliminary Results of the NASA Beacon Receiver for Alphasat Aldo Paraboni TDP5 Propagation Experiment

NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have initiated a joint propagation campaign within the framework of the Alphasat propagation experiment to characterize rain attenuation, scintillation, and gaseous absorption effects of the atmosphere in the 40 GHz band. NASA GRC has developed and installed a K/Q-band (20/40 GHz) beacon receiver at the POLIMI campus in Milan, Italy, which receives the 20/40 GHz signals broadcast from the Alphasat Aldo Paraboni TDP#5 beacon payload. The primary goal of these measurements is to develop a physical model to improve predictions of communications systems performance within the Q-band. Herein, we describe the design and preliminary performance of the NASA propagation terminal, which has been installed and operating in Milan since May 2014. The receiver is based upon a validated Fast Fourier Transform (FFT) I/Q digital design approach utilized in other operational NASA propagation terminals, but has been modified to employ power measurement via a frequency estimation technique and to coherently track and measure the amplitude of the 20/40 GHz beacon signals. The system consists of a 1.2-m K-band and a 0.6-m Qband Cassegrain reflector employing synchronous open-loop tracking to track the inclined orbit of the Alphasat satellite. An 8 Hz sampling rate is implemented to characterize scintillation effects, with a 1-Hz measurement bandwidth dynamic range of 45 dB. A weather station with an optical disdrometer is also installed to characterize rain drop size distribution for correlation with physical based models.

propagation↗

Metering Wheel-Wire Track Wire Boom Deployment Mechanism

The NASA MMS Spin Plane Double Probe (SDP) Deployer utilizes a helical path, rotating Metering Wheel and a spring loaded Wire "Holding" Track to pay out a "fixed end" 57 meter x 1.5 mm diameter Wire Boom stored between concentric storage cylinders. Unlike rotating spool type storage devices, the storage cylinders remain stationary, and the boom wire is uncoiled along the length of the cylinder via the rotation of the Metering Wheel. This uncoiling action avoids the need for slip-ring contacts since the ends of the wire can remain stationary. Conventional fixed electrical connectors (Micro-D type) are used to terminate to operational electronics.

Granoff, Mark S.↗

Orbit Stability of OSIRIS-REx in the Vicinity of Bennu Using a High-Fidelity Solar Radiation Model

The OSIRIS-REx mission (Origins Spectral Interpretation Resource Identification Security Regolith EXPlorer) is an asteroid sample return mission to Bennu (RQ36) that is scheduled to launch in 2016. The planned science operations precluding the small retrieval involve operations in terminator orbits (orbit plane is perpendicular to the sun). Over longer durations the solar radiation pressure (SRP) perturbs the orbit causing it to precess. Our work involves: modeling high fidelity SRP model to capture the perturbations during attitude changes; design a stable orbit from the high fidelity models to analyze the stability over time.

Williams, Trevor↗

Performance of the NASA Beacon Receiver for the Alphasat Aldo Paraboni TDP5 Propagation Experiment

NASA Glenn Research Center (GRC) and the Politecnico di Milano (POLIMI) have initiated a joint propagation campaign within the framework of the Alphasat propagation experiment to characterize rain attenuation, scintillation, and gaseous absorption effects of the atmosphere in the 40 gigahertz band. NASA GRC has developed and installed a K/Q-band (20/40 gigahertz) beacon receiver at the POLIMI campus in Milan, Italy, which receives the 20/40 gigahertz signals broadcast from the Alphasat Aldo Paraboni Technology Demonstration Payload (TDP) no. 5 beacon payload. The primary goal of these measurements is to develop a physical model to improve predictions of communications systems performance within the Q-band. Herein, we describe the design and preliminary performance of the NASA propagation terminal, which has been installed and operating in Milan since June 2014. The receiver is based upon a validated Fast Fourier Transform (FFT) I/Q digital design approach utilized in other operational NASA propagation terminals, but has been modified to employ power measurement via a frequency estimation technique and to coherently track and measure the amplitude of the 20/40 gigahertz beacon signals. The system consists of a 1.2-meter K-band and a 0.6-meter Q-band Cassegrain reflector employing synchronous open-loop tracking to track the inclined orbit of the Alphasat satellite. An 8 hertz sampling rate is implemented to characterize scintillation effects, with a 1-hertz measurement bandwidth dynamic range of 45 decibels. A weather station with an optical disdrometer is also installed to characterize rain drop size distribution for correlation with physical based models.

propagation↗

Human Factors Research Considerations for Terminal Area Urban Air Mobility Operations

In this presentation, we discuss the human factors research challenges from introducing greater levels of automation in a future air transportation concept called Urban Air Mobility (UAM). UAM is an air transportation concept that aims to provide air transportation services to the daily commuter, as well as emergency response and package delivery. The principal innovation over current day large air transport system is the greater distribution of important safety functions to automated and human agents; these functions include air traffic management, traditionally an air traffic controller responsibility. A central aspect of UAM is the development of an automated air traffic manager, whose primary responsibility is to approve airspace access for vehicle operators. Vehicle operator roles may include onboard and remote pilots, as well as a human manager who will supervise an entire fleet. Alternatively, both fleet manager and vehicle operators can be merged into a single role – a feasible option if UAM aircraft are autonomous. In lieu of tower controllers, vertiport managers, with the assistance of automation, will manage arrival and departure schedules between vertiports, as well as supervise surface operations. Our approach here will be to introduce use cases currently being developed by NASA, and then provide preliminary definitions for each of the roles introduced above and how coordination between them can be configured to support the operations within the use cases described. Subsequently, we review the tools and interfaces being developed to support the various roles. To conclude, we present current human factors work related to defining the roles above and suggest future work to advance the UAM concept.

trial planning↗