SEARCH · Engineering Papers

Results for “operations flight operations”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 991 records · Page 55

All sources NASA NTRS DOE OSTI

NASA NTRS1990

A new environment for multiple spacecraft power subsystem mission operations

The engineering analysis subsystem environment (EASE) is being developed to enable fewer controllers to monitor and control power and other spacecraft engineering subsystems. The EASE prototype has been developed to support simultaneous real-time monitoring of several spacecraft engineering subsystems. It is being designed to assist with offline analysis of telemetry data to determine trends, and to help formulate uplink commands to the spacecraft. An early version of the EASE prototype has been installed in the JPL Space Flight Operations Facility for online testing. The EASE prototype is installed in the Galileo Mission Support Area. The underlying concept, development, and testing of the EASE prototype and how it will aid in the ground operations of spacecraft power subsystems are discussed.

Bahrami, K. A.↗

NASA NTRS2003

AWS Figure of Merit (FOM) Developed Parameters from Static, Transonic Model Tests

This paper provides an approach to answer the question of whether one can rely solely on static data taken during a transonic model test to provide the certainty needed that a new aircraft will or will not have Abrupt Wing Stall (AWS) events during its flight operations. By comparing traditional- and alternate-static-Figures of Merit (FOMs) with the Free-To-Roll (FTR) response data, a rational basis for assessing the merits of using standard testing techniques for the prediction of AWS events has been established. Using the FTR response data as a standard, since these results compare well with flight, the conclusion from this study is that neither traditional nor alternate FOMs can be trusted to provide an indication as to whether a configuration will or will not have AWS tendencies. Even though these FOMs may flag features which have a high degree of correlation with the FTR response data, there are as many or more of these FOM flagged features which do not correlate. Thus, one needs to use the FTR rig to assess AWS tendencies on new configurations.

Lamar, J. E.↗

NASA NTRS2007

Aeroheating Analysis for the Mars Reconnaissance Orbiter with Comparison to Flight Data

The aeroheating environment of the Mars Reconnaissance Orbiter (MRO) has been analyzed using the direct simulation Monte Carlo and free-molecular techniques. The results of these analyses were used to develop an aeroheating database to be used for the preflight planning and the in-flight operations support for the aerobraking phase of the MRO mission. The aeroheating predictions calculated for the MRO include the heat transfer coefficient (CH) over a range of angles-of-attack, sideslip angles, and number densities. The effects of flow chemistry, surface temperature, and surface grid resolution were also investigated to determine the aeroheating database uncertainties. Flight heat flux data has been calculated from surface temperature sensor data returned to Earth from the MRO in orbit around Mars during the aerobraking phase of its mission. The heat flux data have been compared to the aeroheating database and agree favorably.

Liechty, Derek S.↗

NASA NTRS1989

The reusable reentry satellite - A mission and system description and operational concept

A significant need exists for a system which will provide the life science experimenter with relatively frequent and inexpensive access to the space environment. To fulfill this need, a project and spacecraft system described as the Reusable Reentry Satellite (RRS) or LifeSat has been proposed by NASA. The RRS provides a relatively inexpensive method of access to space for extended periods of time and eventual intact recovery of the experiments on the earth's surface. The payload support requirements, flight operations concept are reviewed and the mission and system of the RRS are described in detail.

Swenson, Byron L.↗

NASA NTRS1991

Strategies for the study of flightcrew behavior

The performance of any flightcrew at any given time is determined by multiple factors ranging from characteristics of individual crewmembers to the regulations governing flight operations. Attention is given to microcoding of communications, survey data on crewmember attitudes as indicators of culture and crew resource management (CRM) training effects, and systematic observation of crew behavior. Consideration is given to advanced CRM training of evaluators, analyses of crew behavior by aircraft type and characteristics, and survey data on crew reactions to line oriented flight training.

Helmreich, Robert L.↗

NASA NTRS1998

VR for Mars Pathfinder

Virtual reality (VR) technology has played an integral role for Mars Pathfinder mission, operations Using an automated machine vision algorithm, the 3d topography of the Martian surface was rapidly recovered fro -a the stereo images captured. by the Tender camera to produce photo-realistic 3d models, An advanced, interface was developed for visualization and interaction with. the virtual environment of the Pathfinder landing site for mission scientists at the Space Flight Operations Facility of the Jet Propulsion Laboratory. The VR aspect of the display allowed mission scientists to navigate on Mars in Bud while remaining here on Earth, thus improving their spatial awareness of the rock field that surrounds the lenders Measurements of positions, distances and angles could be easily extracted from the topographic models, providing valuable information for science analysis and mission. planning. Moreover, the VR map of Mars has also been used to assist with the archiving and planning of activities for the Sojourner rover.

Blackmon, Theodore↗

NASA NTRS2015

Global Precipitation Measurement Mission Launch and Commissioning

During launch and early operation of the Global Precipitation Measurement (GPM) Mission, the Guidance, Navigation and Control (GNC) analysis team encountered four main on orbit anomalies. These include: (1) unexpected shock from Solar Array deployment, (2) momentum buildup from the Magnetic Torquer Bars (MTBs) phasing errors, (3) transition into Safehold due to albedo-induced Course Sun Sensor (CSS) anomaly, and (4) a flight software error that could cause a Safehold transition due to a Star Tracker occultation. This paper will discuss ways GNC engineers identified and tracked down the root causes. Flight data and GNC on board models will be shown to illustrate how each of these anomalies were investigated and mitigated before causing any harm to the spacecraft. On May 29, 2014, GPM was handed over to the Mission Flight Operations Team after a successful commissioning period. Currently, GPM is operating nominally on orbit, collecting meaningful scientific data that will significantly improve our understanding of the Earth's climate and water cycle.

Guidance Navigation and Control↗

NASA NTRS2024

Designing Payload and Spaceflight Operations for Plants From Extreme 1 Terrestrial Environments

Terrestrial plants from the edges of the limits of life are likely to harbor genes that confer an advantage in deep space environments. These plants are seemingly capable of performing mission critical functions under prevailing deep space conditions while informing directed gene manipulation in target plant species. However, their adaptations to physiologically extreme habitats may hinder efficacy of routine laboratory techniques established for model plants. Here we present the development of Antarctic moss Ceratodon purpureus payload and flight operations for the ARTEMOSS experiment to the ISS astute of limited physical space and crew time. We demonstrate that the hydrophobic surface of Antarctic moss impedes chemical tissue fixation and precludes usage of RNAlater coupled with payload hardware deployed in standard plant spaceflight experiments. We show that deep-freezing the moss tissue on Petri plates provides adequate tissue fixation and allows for extraction of high-quality RNA suitable for gene expression profiling. We replaced hardware with stacks of Petri plates housing Antarctic moss and chemical fixation with deep-freeze in cryogenic GLACIER freezer. Our design can be translated to other plant species, expanding current techniques of experimentation with plants from extreme terrestrial environments aimed toward advancing human space exploration.

Agata K Zupanska↗

NASA NTRS1974

Orbital maneuvering subsystem functional path analysis for performance monitoring fault detection and annunciation

The functional paths of the Orbital Maneuver Subsystem (OMS) is defined. The operational flight instrumentation required for performance monitoring, fault detection, and annunciation is described. The OMS is a pressure fed rocket engine propulsion subsystem. One complete OMS shares each of the two auxiliary propulsion subsystem pods with a reaction control subsystem. Each OMS is composed of a pressurization system, a propellant tanking system, and a gimbaled rocket engine. The design, development, and operation of the system are explained. Diagrams of the system are provided.

Keesler, E. L.↗

NASA NTRS2002

Revolutionary Concepts for Helicopter Noise Reduction: SILENT Program

As part of a NASA initiative to reduce helicopter main rotor noise, a Phase 1 study has been performed of candidate noise reduction concepts. Both conventional and novel design technologies have been analyzed that reduce the community impact of helicopter operations. In this study the noise reduction potential and design implications are assessed for conventional means of noise reduction, e.g., tip speed reduction, tip shapes and airfoil tailoring, and for two innovative design concepts: modulated blade spacing and x-force control. Main rotor designs that incorporate modulated blade spacing are shown to have reduced peak noise levels in most flight operations. X-force control alters the helicopter's force balance whereby the miss distance between main rotor blades and shed vortices can be controlled. This control provides a high potential to mitigate BVI noise radiation. Each concept is evaluated using best practice design and analysis methods, achieving the study's aim to significantly reduce noise with minimal performance degradation and no vibration increase. It is concluded that a SILENT main rotor design, incorporating the modulated blade spacing concept, offers significantly reduced noise levels and the potential of a breakthrough in how a helicopter's sound is perceived and judged. The SILENT rotor represents a definite advancement in the state-of-the-art and is selected as the design concept for demonstration in Phase 2. A Phase 2 Implementation Plan is developed for whirl cage and wind tunnel evaluations of a scaled model SILENT rotor.

Edwards, Bryan↗

NASA NTRS2015

Global Precipitation Measurement Mission Launch and Commissioning

During launch and early operation of the Global Precipitation Measurement (GPM) Mission, the Guidance, Navigation, and Control (GN&C) analysis team encountered four main on-orbit anomalies. These include: (1) unexpected shock from Solar Array deployment, (2) momentum buildup from the Magnetic Torquer Bars (MTBs) phasing errors, (3) transition into Safehold due to albedo induced Course Sun Sensor (CSS) anomaly, and (4) a flight software error that could cause a Safehold transition due to a Star Tracker occultation. This paper will discuss ways GN&C engineers identified the anomalies and tracked down the root causes. Flight data and GN&C on-board models will be shown to illustrate how each of these anomalies were investigated and mitigated before causing any harm to the spacecraft. On May 29, 2014, GPM was handed over to the Mission Flight Operations Team after a successful commissioning period. Currently, GPM is operating nominally on orbit, collecting meaningful scientific data that will significantly improve our understanding of the Earth's climate and water cycle.

Guidance Navigation and Control↗

NASA NTRS2001

Spacecraft Thermal Control

Thermal control of the spacecraft is typically achieved by removing heat from the spacecraft parts that tend to overheat and adding heat to the parts that tend get too cold. The equipment on the spacecraft can get very hot if it is exposed to the sun or have internal heat generation. The pans also can get very cold if they are exposed to the cold of deep space. The spacecraft and instruments must be designed to achieve proper thermal balance. The combination of the spacecraft's external thermal environment, its internal heat generation (i.e., waste heat from the operation of electrical equipment), and radiative heat rejection will determine this thermal balance. It should also be noted that this is seldom a static situation, external environmental influences and internal heat generation are normally dynamic variables which change with time. Topics discussed include thermal control system components, spacecraft mission categories, spacecraft thermal requirements, space thermal environments, thermal control hardware, launch and flight operations, advanced technologies for future spacecraft,

Birur, Gajanana C.↗

NASA NTRS1997

Coping with Irregular Operations: Implications for a Free Flight Environment

Irregular operations involve disruption of scheduled airline operations. They ate of concern to the carriers because they cost money, require personnel effort, and may harm customer good will. Irregular operations may result from aircraft system malfunctions that take planes out of service or result in cancellations, Might system problems or passenger medical emergencies that require diversions, local airport problems that may close down a runway, or weather systems that restrict flow into airports or regions. At the heart of responding to irregular operations is distributed decision making by members of airline operations centers, pilots, and the air traffic control system. Six U.S. carriers participated in a study in which we observed strategies used by operations center personnel to handle various classes of irregular operations. We focused on situations that are most disruptive to regular operations and are most difficult to cope with. We also sought to identify classes of events that would be most affected by changes in the air traffic management system. How a carrier deals with disruptions to its schedule reflects its philosophy and primary goals, as well as its resources. Size and type of operations (short or long-haul) determine which problems have priority. Each airline has different technological support tools to aid in flight planning and replanning, and some carriers have established contingency procedures for coping with various situations. We also examined differences in extent and type of interaction between ABC personnel and various elements of the air traffic system as they managed various problems: who interacts with AM what situations prompt interaction, how often these occur, and the outcomes and Perceived benefits. Use of the expanded NRP program was also studied, along with its advantages to the individual companies. We also examined the implications of the proposed change to a free flight environment on airline strategies for coping with irregular operations.

Orasanu, Judith↗

NASA NTRSDate not supplied

On the Modeling of Urban Air Mobility Vehicle Takeoff and Landing Operations in the FAA Aviation Environmental Design Tool

Urban air mobility (UAM) vehicles are anticipated to operate in close proximity to the public. A possible barrier to the introduction of UAM vehicles as a transit solution is their community noise impact, particularly around vertiports. The Federal Aviation Administration Aviation Environmental Design Tool (AEDT) is the mandated tool to assess aircraft noise and other environmental impacts due to federal actions at civilian airports, vertiports, or in U.S. airspace for commercial flight operations. However, AEDT was designed to model fixed-wing aircraft and conventional helicopter operations, not UAM vehicles. Prior work by the authors showed significant differences in noise contours of UAM departures and approaches when modeling operations as fixed-wing and helicopter types in AEDT. This paper identifies the sources of those differences. Additionally, a NASA time-marching simulation tool is used to generate noise exposure predictions for equivalent operations to help identify differences associated with the noise model implemented in AEDT and offer possible changes to assess UAM community noise impact more consistently with simulation-based modeling.

aeroacoustics↗

NASA NTRSDate not supplied

On the Modeling of Urban Air Mobility Vehicle Takeoff and Landing Operations in the FAA Aviation Environmental Design Tool

aeroacoustics↗

NASA NTRS1975

Spacelab - A key element in the Space Shuttle Space Transportation System

Spacelab will be a key element in the Space Transportation System (STS) to be initiated with the advent of the first operational flight of Space Shuttle in 1980. Spacelab is an international, cooperative venture between the European Space Agency (ESA) and the National Aeronautics and Space Administration (NASA), which is structured to provide the scientific community an earthlike laboratory in space by 1980. The responsibilities of both ESA and NASA are divided into design and development to be accomplished by ESA and the experiment integration and operation with the Space Shuttle by NASA. While the Spacelab is a key element in the STS, it is highly dependent on other elements in the system for its resources and payload support capabilities. This paper presents the relationship of the Spacelab to other elements and the operational planning that NASA is undertaking to make the Spacelab a flexible and efficient laboratory in space.

Lee, T. J.↗

NASA NTRS1995

Flight test of a low-altitude helicopter guidance system with obstacle avoidance capability

Military aircraft regularly conduct missions that include low-atltitude, near-terrain flight in order to increase covertness and payload effectiveness. Civilian applications include airborne fire fighting, police surveillance, search and rescue, and helicopter emergency medical service. Several fixed-wing aircraft now employ terrain elevation maps and forward-pointed radars to achieve automated terrain following or terrain avoidance flight. Similar systems specialized to helicopters and their flight regime have not received as much attention. A helicopter guidance system relying on digitized terrain elevation maps has been developed that employs airborne navigation, mission requirements, aircraft performance limits, and radar altimeter returns to generate a valley-seeking, low-altitude trajectory between waypoints. The guidance trajectory is symbolically presented to the pilot on a helmet mounted display. This system has been flight tested to 150 ft (45.7 m) above ground level altitude at 80 kts, and is primarily limited by the ability of the pilot to perform manual detection and avoidance of unmapped hazards. In this study, a wide field of view laser radar sensor has been incorporated into this guidance system to assist the pilot in obstacle detection and avoidance, while expanding the system's operational flight envelope. The results from early flight tests of this system are presented. Low-altitude missions to 100 ft (30.5 m) altitude at 80n kts in the presence of unmapped natural and man-made obstacles were demonstrated while the pilot maintained situational awareness and tracking of the guidance trajectory. Further reductions in altitude are expected with continued flight testing.

Zelenka, Richard E.↗

NASA NTRS2016

Real-Time Safety Monitoring and Prediction for the National Airspace System

As new operational paradigms and additional aircraft are being introduced into the National Airspace System (NAS), maintaining safety in such a rapidly growing environment becomes more challenging. It is therefore desirable to have both an overview of the current safety of the airspace at different levels of granularity, as well an understanding of how the state of the safety will evolve into the future given the anticipated flight plans, weather forecasts, predicted health of assets in the airspace, and so on. To this end, we have developed a Real-Time Safety Monitoring (RTSM) that first, estimates the state of the NAS using the dynamic models. Then, given the state estimate and a probability distribution of future inputs to the NAS, the framework predicts the evolution of the NAS, i.e., the future state, and analyzes these future states to predict the occurrence of unsafe events. The entire probability distribution of airspace safety metrics is computed, not just point estimates, without significant assumptions regarding the distribution type and or parameters. We demonstrate our overall approach by predicting the occurrence of some unsafe events and show how these predictions evolve in time as flight operations progress.

National Airspace System↗