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At least 1,315 records · Page 73
All sourcesNASA NTRSDOE OSTI
NASA NTRS2010

Cruise-Efficient Short Takeoff and Landing (CESTOL): Potential Impact on Air Traffic Operations

The National Aeronautics and Space Administration (NASA) is investigating technological and operational concepts for introducing Cruise-Efficient Short Takeoff and Landing (CESTOL) aircraft into a future US National Airspace System (NAS) civil aviation environment. CESTOL is an aircraft design concept for future use to increase capacity and reduce emissions. CESTOL provides very flexible takeoff, climb, descent and landing performance capabilities and a high-speed cruise capability. In support of NASA, this study is a preliminary examination of the potential operational impact of CESTOL on airport and airspace capacity and delay. The study examines operational impacts at a subject site, Newark Liberty Intemational Airport (KEWR), New Jersey. The study extends these KEWR results to estimate potential impacts on NAS-wide network traffic operations due to the introduction of CESTOL at selected major airports. These are the 34 domestic airports identified in the Federal Aviation Administration's Operational Evolution Plan (OEP). The analysis process uses two fast-time simulation tools to separately model local and NAS-wide air traffic operations using predicted flight schedules for a 24-hour study period in 2016. These tools are the Sen sis AvTerminal model and NASA's Airspace Concept Evaluation System (ACES). We use both to simulate conventional-aircraft-only and CESTOL-mixed-with-conventional-aircraft operations. Both tools apply 4-dimension trajectory modeling to simulate individual flight movement. The study applies AvTerminal to model traffic operations and procedures for en route and terminal arrival and departures to and from KEWR. These AvTerminal applications model existing arrival and departure routes and profiles and runway use configurations, with the assumption jet-powered, large-sized civil CESTOL aircraft use a short runway and standard turboprop arrival and departure procedures. With these rules, the conventional jet and CESTOL aircraft are procedurally separated from each other geographically and in altitude during tenninal airspace approach and departure operations, and each use a different arrival runway. AvTeminal implements its unique Focal-point Scheduling Process to sequence, space and delay aircraft to resolve spacing and overtake conflicts among flights in the airspace and airport system serving KEWR. This Process effectively models integrated arrival and departure operations. AvTerminal assesses acceptance rates and delay magnitude and causality at selected locations, including en route outer boundary fixes, tenninal airspace arrival and departure boundary fixes, terminal airspace arrival merge and departure diverge fixes, and runway landing and takeoff runways. The analysis compares the resulting capacity impacts, flight delays and delay sources between CESTOL and conventional KEWR operations. AvTerminal quantitative results showed that CESTOL has significant capability to increase airport arrival acceptance rates (35-40% at KEWR) by taking advantage of otherwise underused airspace and runways where available. The study extrapolates the AvTerminal-derived KEWR peak arrival and departure acceptance rates to estimate capacity parameter values for each of the OEP airports in the ACES modeling of traffic through the entire NAS network. The extrapolations of acceptance rates allow full, partial or no achievement of CESTOL capacity gains at an OEP airport as determined by assessments of the degree to which local procedures allow leveraging of CESTOL capabilities. These assessments consider each OEP airport's runway geometries, runway system configurations, airport and airspace operations, and potential CESTOL traffic loadings. The ACES modeling, simulates airport and airspace spacing constraints imposed by airport runway system, terminal and en route air traffic control and traffic flow management operations using airport acceptance rates representing conventional-aircraft-only and CESTOL-mixed operations. CEOL aircraft are assumed to have Mach 0.8, and alternatively Mach 0.7, cruise speeds to examine compatibility with conventional aircraft operations in common airspace. The ACES results provides estimates of CESTOL delay impact NAS-wide and at OEP airports due to changes in OEP airport acceptance rates and changes in en route airspace potential conflict rates. Preliminary results show meaningful nationwide delay reductions (20%) due to CESTOL operations at 34 major domestic airports.

Couluris, G. J.↗
NASA NTRS2011

The Analysis of Rush Orders Risk in Supply Chain: A Simulation Approach

Satisfying customers by delivering demands at agreed time, with competitive prices, and in satisfactory quality level are crucial requirements for supply chain survival. Incidence of risks in supply chain often causes sudden disruptions in the processes and consequently leads to customers losing their trust in a company's competence. Rush orders are considered to be one of the main types of supply chain risks due to their negative impact on the overall performance, Using integrated definition modeling approaches (i.e. IDEF0 & IDEF3) and simulation modeling technique, a comprehensive integrated model has been developed to assess rush order risks and examine two risk mitigation strategies. Detailed functions sequence and objects flow were conceptually modeled to reflect on macro and micro levels of the studied supply chain. Discrete event simulation models were then developed to assess and investigate the mitigation strategies of rush order risks, the objective of this is to minimize order cycle time and cost.

Mahfouz, Amr↗
NASA NTRS2012

Climate Change Impacts on the Built Environment in the United States and Implications for Sustainability

As an integral part of the National Climate Assessment (NCA), technical assessment reports for 13 regions in the U.S. that describe the scientific rationale to support climate change impacts within the purview of these regions, and provide adaptation or mitigation measures in response to these impacts. These technical assessments focus on climate change impacts on sectors that are important environmental, biophysical, and social and economic aspects of sustainability within the U.S.: Climate change science, Ecosystems and biodiversity, Water resources, Human health, Energy supply and use, Water/energy/land use, Transportation, Urban/infrastructure/vulnerability, Agriculture, Impacts of climate change on tribal/indigenous and native lands and resources, Forestry, Land use/land cover change, Rural communities development, and Impacts on biogeochemical cycles, with implications for ecosystems and biodiversity. There is a critical and timely need for the development of mitigation and adaptation strategies in response to climate change by the policy and decision making communities, to insure resiliency and sustainability of the built environment in the future.

Quattrochi, Dale A.↗
NASA NTRS2015

Recommendations on Future Science and Engineering Studies for Ocean Color

The Ocean Health Index measured Ecological Integrity as the relative condition of assessed species in a given location. This was calculated as the weighted sum of the International Union for Conservation of Natures (IUCN) assessments of species. Weights used were based on the level of extinction risk following Butchart et al.2007: EX (extinct) 0.0, CR (critically endangered) 0.2, EN (endangered) 0.5, VU (vulnerable) 0.7, NT (not threatened) 0.9, and LC (least concern) 0.99. For primarily coastal goals, the spatial average of these per pixel scores was based on a 3nmi buffer; for goals derived from all ocean waters, the spatial average was computed for the entire EEZ.

Geo-Cape↗
NASA NTRS2016

Remote Imaging of Exploration Flight Test-1 (EFT-1) Entry Heating Risk Reduction

A Measure of Performance (MOP) identified with an Exploration Flight Test-1 (EFT-1) Multi- Purpose Crew Vehicle (MPCV) Program Flight Test Objective (FTO) (OFT1.091) specified an observation during reentry though external ground-based or airborne assets with thermal detection capabilities. The objective of this FTO was to be met with onboard Developmental Flight Instrumentation (DFI), but the MOP for external observation was intended to provide complementary quantitative data and serve as a risk reduction in the event of anomalous DFI behavior (or failure). Mr. Gavin Mendeck, the Entry, Descent, and Landing (EDL) Phase Engineer for the MPCV Program (Vehicle Integration Office/Systems & Mission Integration) requested a risk-reduction assessment from the NASA Engineering and Safety Center (NESC) to determine whether quantitative imagery could be obtained from remote aerial assets to support the external observation MOP. If so, then a viable path forward was to be determined, risks identified, and an observation pursued. If not, then the MOP for external observation was to be eliminated.

Schuster, David M.↗
NASA NTRS2004

Inflatable space structures technology development for large radar antennas.

There has been recent interest in inflatable space-structures technology for possible applications on US. Department of Defense (DOD) missions because of the technology's potential for high mechanical-packaging efficiency, variable stowed geometry, and deployment reliability. In recent years, the DOD-sponsored Large Radar Antenna Program (LRA) applied this new technology to a baseline concept: an inflatablehigidizable (lU) perimeter-truss structure supporting a meshhet parabolic-reflector antenna. The program addressed (a) truss concept development, (b) rigidizable materials concepts assessment, (c) meshhet concept selection and integration, and (d) developed potential mechanical-system p erformance estimates. Critical and enabling technologies were validated, especially orbital radiation durable rigidized materials, and high modulus, inflatable-deployablet russ numbers.

Willis, Paul↗
NASA NTRS2021

Technology Readiness Level as the Foundation of Human Readiness Level

Communication of the maturity of technology through the program/product life cycles helps enhance risk management from the beginning and support decision-making strategies for research, development, and allocation of resources. Currently, many organizations use the technology readiness level (TRL) as a simple metric to indicate the maturity of the technology. This article will discuss the TRL history, define the TRL levels, show how the TRL relates to the technology life cycle, and how the TRL framework contributes to the human readiness level (HRL) structure. Through the TRL advantages and disadvantages, this article will show how the TRL falls short in numerous areas of engineering, including the integration readiness of system/subsystem components and assessment of the readiness of the technology to operate within the human capabilities and limitations. Yet the article also shows how the TRL serves as the foundation for HRL.

George Salazar↗
NASA NTRSDate not supplied

Comparison of Two Community Noise Models Applied to a NASA Urban Air Mobility Concept Vehicle

Predictions of community noise exposure from a NASA urban air mobility (UAM) concept vehicle have been conducted for representative operations using the FAA Aviation Environmental Design Tool (AEDT) in order to demonstrate modeling tool interoperability and assess applicability, capabilities and limitations of integrated noise modeling tools. To both quantify limitations and highlight other capabilities, a comparative analysis is performed using a time-domain simulation method, in particular, using the Volpe Advanced Acoustic Model (AAM). Using the same source noise model, the 3D directivity of a UAM concept vehicle is predicted in terms of aeroacoustic pressure time histories at a sphere of observer positions near the vehicle. In addition to distilling those data to a set of noise-power-distance data for input to AEDT, the data are processed preserving spectral directivity, into one-third and one-twelfth octave bands for input to AAM. Results from AEDT and AAM modeling are provided for a variety of metrics to demonstrate the effect that source noise directivity and propagation modeling fidelity have on predicted results at receptors over a study area.

urban air mobility↗
NASA NTRSDate not supplied

Comparison of Two Community Noise Models Applied to a NASA Urban Air Mobility Concept Vehicle

Predictions of community noise exposure from a NASA urban air mobility (UAM) concept vehicle have been conducted for representative operations using the FAA Aviation Environmental Design Tool (AEDT) in order to demonstrate modeling tool interoperability and assess applicability, capabilities and limitations of integrated noise modeling tools. To both quantify limitations and highlight other capabilities, a comparative analysis is performed using a time-domain simulation method, in particular, using the Volpe Advanced Acoustic Model (AAM). Using the same source noise model, the 3D directivity of a UAM concept vehicle is predicted in terms of aeroacoustic pressure time histories at a sphere of observer positions near the vehicle. In addition to distilling those data to a set of noise-power-distance data for input to AEDT, the data are processed preserving spectral directivity, into one-third and one-twelfth octave bands for input to AAM. Results from AEDT and AAM modeling are provided for a variety of metrics to demonstrate the effect that source noise directivity and propagation modeling fidelity have on predicted results at receptors over a study area.

urban air mobility↗
NASA NTRSDate not supplied

Gateway Implementation of Cybersecurity Requirements

Cyber threats are a constant present-day reality for any type of business -- Space exploration is not excluded from these threats either. The Gateway Program is one of NASA’s latest initiatives that extend space exploration beyond low earth orbit. Gateway allows for NASA to prove technologies and mature systems necessary to live and work on another celestial body before embarking on multi-year missions to Mars. The Gateway is a small, human-tended space station in orbit around the Moon. With the increased autonomy, distance and criticality of systems, cybersecurity is one of the critical subsystems that touches and integrates with most if not all subsystems of the Gateway. Building a gateway to the lunar orbit is no simple task. In this presentation, we outline an approach that the Gateway team adopted in creating a cyber safe and robust vehicle to support operations and assure protection of the critical functions. Gateway Program is required to implement National Institute of Standards and Technology (NIST) guidelines to adhere to the Federal Information Security Modernization Act (FISMA). NIST provides a framework for managing and controlling cybersecurity risks by defining cybersecurity controls and methodologies for implementation. The NIST framework is based upon the system, data within the system, integrations with external systems, and risk assessments to determine impacts for each of those systems. The goals and objectives are to identify appropriate security controls that fulfill and map to the NIST 800-53 framework. The implementation process involves developing an organizational understanding to manage cybersecurity risk to systems, people, assets, data, and capabilities. NIST Security controls are interpreted and defined within the Gateway vehicle requirements subsystems specifications. This paper details the approach, implementation, and challenges faced during the development and design phases to address cyber threats during the Gateway vehicle operations.

Svetlana Hanson↗
NASA NTRSDate not supplied

Gateway Implementation of Cybersecurity Requirements

Cybersecurity threats are a constant present-day reality for any type of business -- Space exploration is not excluded from these threats either. The Gateway Program is one of NASA’s latest initiatives that extend space exploration beyond low earth orbit. Gateway allows for NASA to prove technologies and mature systems necessary to live and work on another celestial body before embarking on multi-year missions to Mars. The Gateway is a small, human-tended space station in orbit around the Moon. With the increased autonomy, distance and criticality of systems, cybersecurity is a critical discipline that touches and integrates with most if not all subsystems of the Gateway. Building a gateway to the lunar orbit is no simple task. In this presentation, we outline an approach that the Gateway team adopted in creating a cyber safe and robust vehicle to support operations and assure protection of the critical functions. Gateway Program is required to implement National Institute of Standards and Technology (NIST) guidelines to adhere to the Federal Information Security Modernization Act (FISMA). NIST provides a framework for managing and controlling cybersecurity risks by defining cybersecurity controls and methodologies for implementation. The NIST framework is based upon the system, data within the system, integrations with external systems, and risk assessments to determine impacts for each of those systems. The goals and objectives are to identify appropriate security controls that fulfil and map to the NIST 800-53 framework. The implementation process involves developing an organizational understanding to manage cybersecurity risk to systems, people, assets, data, and capabilities. NIST Security controls are interpreted and defined within the Gateway vehicle requirements subsystems specifications. This paper details the approach, implementation, and challenges faced during the development and design phases to address cyber threats during the Gateway vehicle operations.

Cybersecurity↗
NASA NTRS2023

Subsonic Ultra Green Aircraft Research: Phase IV Final Report – Volume I Mach 0.80 Transonic Truss-Braced Wing High-Speed Design Report

This design report summarizes work performed by the Boeing Subsonic Ultra-Green Aircraft Research (SUGAR) team from December 2016 through June 2018. In Phase IV of the SUGAR program, Boeing is working to improve the productivity of a TTBW configuration by updating the Mach 0.745 vehicle concept to operate efficiently at Mach 0.80. Due to the aerodynamic and structural design challenges associated with adapting the design to a higher speed, design tasks have been broken into several subtasks. The information in this report (Volume I) documents the development of a Mach 0.80 vehicle outer mold line, maturation of TTBW structural concepts, and presents a preliminary high-liftsystem assessment. Results from these studies were integrated into an aircraft-level performance code that estimates the benefits of TTBW technology, both on its own and as a part of the SUGAR integrated technology suite. The aerodynamic performance results presented herein detail the high cruise efficiency of the TTBW concept operating at M=0.80. Results from the RANS code OVERFLOW indicate that the TTBW is aerodynamically well suited for operation at the design M=0.80 transonic cruise Mach number. Aircraft-level performance predictions show that the TTBW offers a 7.2% improvement in fuel burn (per seat) for an economic mission of 900nm, and a 9.0% improvement in fuel burn (per seat) for a 3500nm mission with full passenger payload, relative to an aspect ratio 13 conventional tube and wing configuration of equivalent technology. Integration of the TTBW performance benefits into the SUGAR technology suite shows a 55.9% reduction in fuel burn (for the economic mission) relative to the reference (SUGAR Free) aircraft, which is a consistently sized traditional cantilever wing, single-aisle transport typical of the 2008 fleet. This benefit does not include the performance improvement potential of hybrid-electric systems studied in earlier phases of the SUGAR program Structural concept development work completed in Phase IV has identified several strut attachment concepts that are worth additional development activity – an inboard strut attachment swivel joint concept (which enables the strut to carry axial loads while avoiding strut bending induced by wing twist during flight) significantly simplifies the construction of the main strut. An outboard offset strut attachment concept holds significant potential for further reductions in wing-strut interference drag. Based on work performed to date on Phase IV and the previous phases of the SUGAR program, the TTBW concept continues to remain a viable concept for significantly improving the performance of future aircraft. High-fidelity aerodynamic analysis of the Mach 0.80 TTBW aircraft has shown fuel burn improvement that has exceeded initial expectations despite the increase in cruise Mach number. Structural concept maturation has continued to refine the TTBW structure, and has found no obvious ‘show-stoppers’ to date. Therefore, the potential benefit of improved performance through the use of a very high aspect ratio strut-braced wing continues to warrant additional study

SUGAR↗
NASA NTRSDate not supplied

Space Shuttle Program Dual Docked Operations

Due to the ever-increasing visiting vehicle traffic to and from the International Space Station (ISS) during mated Orbiter/ISS missions, it became apparent to both the ISS Program (ISSP) and the Space Shuttle program (SSP) that there would arise occasions where a visiting vehicle docking and/or undocking could overlap when the Space Shuttle Orbiter was docked to the ISS, referred to as Dual Docked Operations (DDO). The primary concerns were that plumes from the visiting vehicles would cause contamination, corrosion, and erosion to Space Shuttle surfaces and present a toxicity hazard to ground personnel when processing the Space Shuttle after landing. This potential conflict provided the genesis for evaluating risk mitigations to gain maximum flexibility for managing potential visiting vehicle traffic to and from the ISS and to maximize launch and landing opportunities for all visiting vehicles. The overarching goal of this effort was to assess the viability and readiness of the SSP to protect for DDO on any given mission. To assess the viability of performing DDO, the ISSP delivered plume particle fluence (i.e., number of particles per unit area) and contamination deposition based on the visiting vehicle’s proximity operations to the SSP for evaluation. This paper summarizes the concept definition, studies, and analysis results generated by the SSP, ISSP, and Mission Operations Directorate (MOD) for implementing DDO involving the Orbiter and Russian vehicles (RVs). Discussion and results presented herein represent a generic assessment of the SSP and ISSP integrated safety and technical evaluations of DDO involving the Orbiter and RVs. Mission-specific analysis and operational impacts were conducted flight-by-flight as they arose.

Launch vehicles↗
NASA NTRSDate not supplied

Advanced Information Systems Technology for NASA Earth System Digital Twins (ESDT)

ESA and NASA have both started programs to design and develop Digital Twins of the Earth and/or Earth systems. Organized around interconnected, multi-domain, high-scale modeling capabilities, the three major components of an Earth System Digital Twin are a continuously updated Digital Replica of the Earth System of interest, dynamic Forecasting models, and Impact Assessment capabilities. Earth System Digital Twins integrate diverse Earth and human activity models, continuous observations, and information system capabilities to provide unified, comprehensive representations and predictions that can be utilized for monitoring the health of the Planet, as well as for developing actionable information to support decision making. More generally, Digital Twins will help researchers better understand the fundamental Earth systems that impact everything from wildfires to climate change. This Townhall will first provide a short description of ESA’s, NASA’s and CNES’s current efforts in Digital Twins: • Destination Earth (DestinE) is the first initiative of the European Union to create a Digital Twin of the Earth, particularly focused on weather and climate, and as a coordinated effort between the European Centre for Medium-Range Weather Forecasts (ECMWF), ESA and the European Organization for the Exploitation of Meteorological Satellites (EUMETSAT). • Additionally, ESA is developing several Digital Twin Earth Precursor Activities to study some of the key scientific and technical challenges associated with building a “Digital Twin Earth”. These include forests, hydrology, Antarctica, food systems, oceans, and climate hot spots Digital Twin prototypes. • NASA Earth Science Technology Office (ESTO)’s Advanced Information Systems Technology (AIST) Program has started an initiative in Earth System Digital Twins (ESDT), with 14 current projects in this area, developing various information systems technologies and prototypes that will help prepare the development of future NASA Digital Twins. • CNES is currently developing the concept of a Digital Twin Factory (DTF), which relies on a data lake, a high computing capability using clouds and/or HPC and has thematic algorithms and methodologies able to generate registered and coherent layers of information in order to enrich a datacube from which physical indicators can be computed spatially. NASA, ESA and CNES are also currently defining science use cases that will be presented during the townhall; those and a few short discussions of current projects will serve as a starting point to engage a dialogue about Digital Twins of the Earth with the IGARSS community.

earth science remote sensing; Information systems↗
NASA NTRSDate not supplied

Supportability Concepts for Crewed Deep Space Exploration

Supportability—defined as the set of system characteristics that influence the logistics and support required to enable safe and effective operations—will be a much larger driver of mass, risk, and crew time for future human space exploration due to the more challenging mission context. For Mars, systems must operate in a logistically isolated environment for much longer durations than previous missions, which results in a higher probability of system failure and therefore an increased need for maintenance or contingency options. Mars missions also lack access to quick aborts, which increases the consequences of an unrecoverable system failure. Together, this higher likelihood and consequence of failure results in an increase in supportability-related risk. Supportability analysis is an important part of systems development that helps designers better understand the impacts of system and mission decisions on risk, mass, and crew time. The real-world processes that drive maintenance requirements and other supportability-related characteristics are probabilistic, and therefore they require different conceptual approaches and models than are used for more deterministic aspects of space systems. This paper provides an overview of supportability analysis, addresses key concepts, and provides examples of how supportability analysis can be incorporated into system development. Specifically, system supportability involves stochastic processes, and therefore must be evaluated using probabilistic models. These models can be used to perform sensitivity analysis even if system characteristics are not yet fully defined. Failure rates cannot be measured directly, but tests provide valuable data that can help refine those estimates. Human spaceflight architectures are complex, and exhibit coupled behavior that should be examined with integrated systems analysis that includes an assessment of supportability.

Supportability↗
NASA NTRSDate not supplied

Supportability Concepts for Crewed Deep Space Exploration

Supportability—defined as the set of system characteristics that influence the logistics and support required to enable safe and effective operations—will be a much larger driver of mass, risk, and crew time for future human space exploration due to the more challenging mission context. For Mars, systems must operate in a logistically isolated environment for much longer durations than previous missions, which results in a higher probability of system failure and therefore an increased need for maintenance or contingency options. Mars missions also lack access to quick aborts, which increases the consequences of an unrecoverable system failure. Together, this higher likelihood and consequence of failure results in an increase in supportability-related risk. Supportability analysis is an important part of systems development that helps designers better understand the impacts of system and mission decisions on risk, mass, and crew time. The real-world processes that drive maintenance requirements and other supportability-related characteristics are probabilistic, and therefore they require different conceptual approaches and models than are used for more deterministic aspects of space systems. This paper provides an overview of supportability analysis, addresses key concepts, and provides examples of how supportability analysis can be incorporated into system development. Specifically, system supportability involves stochastic processes, and therefore must be evaluated using probabilistic models. These models can be used to perform sensitivity analysis even if system characteristics are not yet fully defined. Failure rates cannot be measured directly, but tests provide valuable data that can help refine those estimates. Human spaceflight architectures are complex, and exhibit coupled behavior that should be examined with integrated systems analysis that includes an assessment of supportability.

Supportability↗