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At least 541 records · Page 30

Operational Characteristics Identification and Simulation Model Verification for Incheon International Airport

Incheon International Airport (ICN) is one of the hub airports in East Asia. Airport operations at ICN have been growing more than 5% per year in the past five years. According to the current airport expansion plan, a new passenger terminal will be added and the current cargo ramp will be expanded in 2018. This expansion project will bring 77 new stands without adding a new runway to the airport. Due to such continuous growth in airport operations and future expansion of the ramps, it will be highly likely that airport surface traffic will experience more congestion, and therefore, suffer from efficiency degradation. There is a growing awareness in aviation research community of need for strategic and tactical surface scheduling capabilities for efficient airport surface operations. Specific to ICN airport operations, a need for A-CDM (Airport - Collaborative Decision Making) or S-CDM(Surface - Collaborative Decision Making), and controller decision support tools for efficient air traffic management has arisen since several years ago. In the United States, there has been independent research efforts made by academia, industry, and government research organizations to enhance efficiency and predictability of surface operations at busy airports. Among these research activities, the Spot and Runway Departure Advisor (SARDA) developed and tested by National Aeronautics and Space Administration (NASA) is a decision support tool to provide tactical advisories to the controllers for efficient surface operations. The effectiveness of SARDA concept, was successfully verified through the human-in-the-loop (HITL) simulations for both spot release and runway operations advisories for ATC Tower controllers of Dallas/Fort Worth International Airport (DFW) in 2010 and 2012, and gate pushback advisories for the ramp controller of Charlotte/Douglas International Airport (CLT) in 2014. The SARDA concept for tactical surface scheduling is further enhanced and is being integrated into NASA's Airspace Technology Demonstration - 2 (ATD-2) project for technology demonstration of Integrated Arrival/Departure/Surface (ADS) operations at CLT. This study is a part of the international research collaboration between KAIA (Korea Agency for Infrastructure Technology Advancement)/KARI (Korea Aerospace Research Institute) and NASA, which is being conducted to validate the effectiveness of SARDA concept as a controller decision support tool for departure and surface management of ICN. This paper presents the preliminary results of the collaboration effort. It includes investigation of the operational environment of ICN, data analysis for identification of the operational characteristics of the airport, construction and verification of airport simulation model using Surface Operations Simulator and Scheduler (SOSS), NASA's fast-time simulation tool.

scheduling↗

Operational Characteristics Identification and Simulation Model Verification for Incheon International Airport

Incheon International Airport (ICN) is one of the hub airports in East Asia. Airport operations at ICN have been growing more than 5 percent per year in the past five years. According to the current airport expansion plan, a new passenger terminal will be added and the current cargo ramp will be expanded in 2018. This expansion project will bring 77 new stands without adding a new runway to the airport. Due to such continuous growth in airport operations and future expansion of the ramps, it will be highly likely that airport surface traffic will experience more congestion, and therefore, suffer from efficiency degradation. There is a growing awareness in aviation research community of need for strategic and tactical surface scheduling capabilities for efficient airport surface operations. Specific to ICN airport operations, a need for A-CDM (Airport - Collaborative Decision Making) or S-CDM (Surface - Collaborative Decision Making), and controller decision support tools for efficient air traffic management has arisen since several years ago. In the United States, there has been independent research efforts made by academia, industry, and government research organizations to enhance efficiency and predictability of surface operations at busy airports. Among these research activities, the Spot and Runway Departure Advisor (SARDA) developed and tested by National Aeronautics and Space Administration (NASA) is a decision support tool to provide tactical advisories to the controllers for efficient surface operations. The effectiveness of SARDA concept, was successfully verified through the human-in-the-loop (HITL) simulations for both spot release and runway operations advisories for ATC Tower controllers of Dallas-Fort Worth International Airport (DFW) in 2010 and 2012, and gate pushback advisories for the ramp controller of Charlotte-Douglas International Airport (CLT) in 2014. The SARDA concept for tactical surface scheduling is further enhanced and is being integrated into NASA's Airspace Technology Demonstration-2 (ATD-2) project for technology demonstration of Integrated Arrival-Departure-Surface (IADS) operations at CLT. This study is a part of the international research collaboration between KAIA (Korea Agency for Infrastructure Technology Advancement), KARI (Korea Aerospace Research Institute) and NASA, which is being conducted to validate the effectiveness of SARDA concept as a controller decision support tool for departure and surface management of ICN. This paper presents the preliminary results of the collaboration effort. It includes investigation of the operational environment of ICN, data analysis for identification of the operational characteristics of the airport, construction and verification of airport simulation model using Surface Operations Simulator and Scheduler (SOSS), NASA's fast-time simulation tool.

surface operations analysis↗

Analyzing Launch Operations using the Spaceport Throughput Analysis Resource (STAR)

NASA’s Kennedy Space Center (KSC) and Cape CanaveralSpace Force Station (CCSFS) are the world’s preeminent multi-user spaceport, providing facilities and launch capabilities to the agency, NASA’s commercial partners, and other government agencies. KSC works to ensure an environment in which NASA’s programs and other users can safely and effectively carry out their operations. Approximately 100 launches are expected to take place in 2024. KSC needs to meet the needs of customers who request launches based on their own schedules, but who may not be aware of KSC-wide resource limitations and external constraints on launch operations. KSC-wide resources include telecommunications, range tracking, commodities such as Helium and Nitrogen, and special equipment needed to support launches. External constraints include seasonal launch operations. Since space vehicles are complex and launch operations are uncertain, unexpected events can also cause delays in operations. The Spaceport Throughput AnalysisResource (STAR) assesses whether a specific set of pro-posed launches and associated activities can be performed given the resources KSC currently has available, and external constraints imposed on KSC operations. STAR integrates short-horizon scheduling and simulation of launches using a monte-carlo approach driven by configurable probabilities of different classes of event outcomes, including de-lays and worst-case use of resources. The resulting analyses inform stakeholders of key constraints preventing customers from being able to perform their missions as desired, and give insight into how to improve spaceport throughput. The rest of the paper is organized as follows. In 2 we de-scribe the problem STAR is intended to solve. In Section3 we formally describe the scheduling problem ingredients. In Section 4 we describe how manifests are simulated. InSection 5 we describe the constraints problem that is solved when rescheduling. In Section 6 we describe what information is recorded during manifest simulation in order to evaluate delays. In Section 7 we describe the specific problem solved for KSC. In Section 8 we describe the challenges of knowledge engineering for STAR.

Planning Scheduling Analysis↗

Future Interagency Range and Spaceport Technologies (FIRST) Formulation Products: 1. Transformational Spaceport and Range Concept of Operations. 2. F.I.R.S.T. Business Case Analysis

The Baseline Report captures range and spaceport capabilities at five sites: KSC, CCAFS, VAFB, Wallops, and Kodiak. The Baseline depicts a future state that relies on existing technology, planned upgrades, and straight-line recapitalization at these sites projected through 2030. The report presents an inventory of current spaceport and range capabilities at these five sites. The baseline is the first part of analyzing a business case for a set of capabilities designed to transform U.S. ground and space launch operations toward a single, integrated national "system" of space transportation systems. The second part of the business case compares current capabilities with technologies needed to support the integrated national "system". The final part, a return on investment analysis, identifies the technologies that best lead to the integrated national system and reduce recurring costs..Numerous data sources were used to define and describe the baseline spaceport and range by identifying major systems and elements and describing capabilities, limitations, and capabilities

Source record↗

An operations and command systems for the extreme ultraviolet explorer

About 40% of the budget of a scientific spacecraft mission is usually consumed by Mission Operations & Data Analysis (MO&DA) with MO driving these costs. In the current practice, MO is separated from spacecraft design and comes in focus relatively late in the mission life cycle. As a result, spacecraft may be designed that are very difficult to operate. NASA centers have extensive MO expertise but often lessons learned in one mission are not exploited for other parallel or future missions. A significant reduction of MO costs is essential to ensure a continuing and growing access to space for the scientific community. We are addressing some of these issues with a highly automated payload operations and command system for an existing mission, the Extreme Ultraviolet Explorer (EUVE). EUVE is currently operated jointly by the Goddard Space Flight Center (GSFC), responsible for spacecraft operations, and the Center for Extreme Ultraviolet Astrophysics (CEA) of the University of California, Berkeley, which controls the telescopes and scientific instruments aboard the satellite. The new automated system is being developed by a team including personnel from the NASA Ames Research Center (ARC), the Jet Propulsion Laboratory (JPL) and the Center for EUV Astrophysics (CEA). An important goal of the project is to provide AI-based technology that can be easily operated by nonspecialists in AI. Another important goal is the reusability of the techniques for other missions. Models of the EUVE spacecraft need to be built both for planning/scheduling and for monitoring. In both cases, our modeling tools allow the assembly of a spacecraft model from separate sub-models of the various spacecraft subsystems. These sub-models are reusable; therefore, building mission operations systems for another small satellite mission will require choosing pre-existing modules, reparametrizing them with respect to the actual satellite telemetry information, and reassembling them in a new model. We briefly describe the EUVE mission and indicate why it is particularly suitable for the task. Then we briefly outline our current work in mission planning/scheduling and spacecraft and instrument health monitoring.

Muscettola, Nicola↗

Flat-plate solar array project: Experimental process system development unit for producing semiconductor-grade silicon using the silane-to-silicon process

The engineering design, fabrication, assembly, operation, economic analysis, and process support research and development for an Experimental Process System Development Unit for producing semiconductor-grade silicon using the slane-to-silicon process are reported. The design activity was completed. About 95% of purchased equipment was received. The draft of the operations manual was about 50% complete and the design of the free-space system continued. The system using silicon power transfer, melting, and shotting on a psuedocontinuous basis was demonstrated.

Source record↗

Design and Optimization of a 3-Stage Axial Supercritical CO2 Compressor

This paper presents the detailed design and optimization of a three-stage axial supercritical carbon dioxide (sCO2) compressor to support the advancement of sCO 2 power cycles, recognized for their efficiency and compactness in energy conversion. The three-stage design is a scaled model of the original nine-stage 100 MW design. The aerodynamic design and structural analysis were performed at the University of Cincinnati, and the results are presented. The first stage of the design has been meticulously manufactured and experimentally tested at University of Notre Dame Turbomachinery Laboratory. The design process starts with the preliminary design process, considering the required operating boundary conditions and geometrical constraints for full stage design. The design is then scaled down to 3-stage based on the power limitation. The definition for design parameters has been inspired from the EEE HPC design and tweaked to fit the sCO 2 operation. Axisymmetric analysis is performed next and the parametric geometry modeler -Tblade3 has been used to create 3D blade geometry from the results which can then be exported for the 3D CFD analysis and optimization. An efficiency of 89.85% is predicted for the final design at the design point.

Compressor↗

Airport Surface Delays and Causes: A Preliminary Analysis

This report summarizes FAA Program Analysis and Operations Research Service (ASD-400)/Lockheed Martin activities and findings related to airport surface delays and causes, in support of NASA Langley Research Center's Terminal Area Productivity (TAP) Program. The activities described in this report were initiated in June 1995. A preliminary report was published on September 30, 1995. The final report incorporates data collection forms filled out by traffic managers, other FAA staff, and an airline for the New York City area, some updates, data previously requested from various sources to support this analysis, and further quantification and documentation than in the preliminary report. This final report is based on data available as of April 12, 1996. This report incorporates data obtained from review and analysis of data bases and literature, discussions/interviews with engineers, air-traffic staff, other FAA technical personnel, and airline staff, site visits, and a survey on surface delays and causes. It includes analysis of delay statistics; preliminary findings and conclusions on surface movement, surface delay sources and causes, runway occupancy time (ROT), and airport characteristics impacting surface operations and delays; and site-specific data on the New York City area airports, which are the focus airports for this report.

Chin, David K.↗

Dynamic and control assessment of the Space Station Freedom payload pointing system

An analysis of the proposed Space Station Freedom Payload Pointing System (PPS) was performed to assess its dynamic payload pointing capability in the dynamic environment of the Space Station Freedom (SSF). In addition, the stability and control the the SSF was examined to verify the capability of its control devices to accommodate the impact of PPS operations. An analysis of the PPS ability to provide continuous, accurate pointing was performed and compared to the program requirements specified in the 1988 Program Definition and Requirement Document (PDRD). Results indicated that the PPS was not able to perform within the program requirements during the worst case scenario of a shuttle hard docking maneuver to the port side SSF docking adapter. The PPS maintained marginal pointing accuracy during crew treadmill activity. The Space Station attitude control system easily accommodated all PPS operations simulated. The PPS caused a negligible impact on the SSF's control environment.

Shannon, David T., Jr.↗

Monte Carlo modeling of exospheric bodies - Mercury

In order to study the interaction with the surface, a Monte Carlo program is developed to determine the distribution with altitude as well as the global distribution of density at the surface in a single operation. The analysis presented shows that the appropriate source distribution should be Maxwell-Boltzmann flux if the particles in the distribution are to be treated as components of flux. Monte Carlo calculations with a Maxwell-Boltzmann flux source are compared with Mariner 10 UV spectrometer data. Results indicate that the presently operating models are not capable of fitting the observed Mercury exosphere. It is suggested that an atmosphere calculated with a barometric source distribution is suitable for more realistic future exospheric models.

Smith, G. R.↗

Lessons Learned During TBCC Design for the NASA-AFRL Joint System Study

NASA and the Air Force Research Laboratory are involved in a Joint System Study (JSS) on Two-Stage-to-Orbit (TSTO) vehicles. The JSS will examine the performance, operability and analysis uncertainty of unmanned, fully reusable, TSTO launch vehicle concepts. NASA is providing a vehicle concept using turbine-based combined cycle (TBCC) propulsion on the booster stage and an all-rocket orbiter. The variation in vehicle and mission requirements for different potential customers, combined with analysis uncertainties, make it problematic to define optimum vehicle types or concepts, but the study is being used by NASA for tool assessment and development, and to identify technology gaps. Preliminary analyses were performed on the entire TBCC booster concept; then higher-fidelity analyses were performed for particular areas to verify results or reduce analysis uncertainties. Preliminary TBCC system analyses indicated that there would be sufficient thrust margin over its mission portion. The higher fidelity analyses, which included inlet and nozzle performance corrections for significant area mismatches between TBCC propulsion requirements versus the vehicle design, resulted in significant performance penalties from the preliminary results. TBCC system design and vehicle operation assumptions were reviewed to identify items to mitigate these performance penalties. The most promising items were then applied and analyses rerun to update performance predictions. A study overview is given to orient the reader, quickly focusing upon the NASA TBCC booster and low speed propulsion system. Details for the TBCC concept and the analyses performed are described. Finally, a summary of "Lessons Learned" are discussed with suggestions to improve future study efforts.

Snyder, Christopher A.↗

Drilling on the Moon and Mars: Developing the Science Approach for Subsurface Exploration with Human Crews

DOMEX (Drilling on the Moon and Mars in Human Exploration) is using analog missions to develop the approach for using human crews to perform science activities on the Moon and Mars involving exploration and sampling of the subsurface. Subsurface science is an important activity that may be uniquely enabled by human crews. DOMEX provides an opportunity to plan and execute planetary mission science activities without the expense and overhead of a planetary mission. Objectives: The objective of this first in a series of DOMEX missions were to 1) explore the regional area to understand the geologic context and determine stratigraphy and geologic history of various geologic units in the area. 2) Explore for and characterize sites for deploying a deep (10 m depth) drilling system in a subsequent field season. 3) Perform GPR on candidate drill sites. 4) Select sites that represent different geological units deposited in different epochs and collect soil cores using sterile procedures for mineralogical, organic and biological analysis. 5) Operate the MUM in 3 different sites representing different geological units and soil characteristics. 6) Collect rock and soil samples of sites visited and analyze them at the habitat. Results: At mission start the crew performed a regional survey to identify major geologic units that were correlated to recognized stratigraphy and regional geologic maps. Several candidate drill sites were identified. During the rest of the mission, successful GPR surveys were conducted in four locations. Soil cores were collected in 5 locations representing soils from 4 different geologic units, to depths up to 1m. Soil cores from two locations were analyzed with PCR in the laboratory. The remainder were reserved for subsequent analysis. XRD analysis was performed in the habitat and in the field on 39 samples, to assist with sample characterization, conservation, and archiving. MUM was deployed at 3 field locations and 1 test location (outside the habitat) where it operated autonomously for 2-4 hours at each site. Depths achieved ranged from 15 to 70 cm depending on the soil compressive strength and the presence and depth of subsurface indurated layers. Subsurface samples weighing 0.5 to 1 g were collected at the deepest depth encountered at each of the sites using the MUM automated sample collection system, and subsequently analyzed with XRD. Downhole inspection of holes produced by MUM with the Raman spectrometer was acquired on two of the holes and spectral features associated with selenite were identified in specific soil layers. Previously unreported fossilized remains of vertebrate fauna from the Jurassic era were discovered during our mission. Analysis of mineral biomarkers associated with this discovery are underway.

Stoker, C. R.↗

Orion Entry, Descent, and Landing Simulation

The Orion Entry, Descent, and Landing simulation was created over the past two years to serve as the primary Crew Exploration Vehicle guidance, navigation, and control (GN&C) design and analysis tool at the National Aeronautics and Space Administration (NASA). The Advanced NASA Technology Architecture for Exploration Studies (ANTARES) simulation is a six degree-of-freedom tool with a unique design architecture which has a high level of flexibility. This paper describes the decision history and motivations that guided the creation of this simulation tool. The capabilities of the models within ANTARES are presented in detail. Special attention is given to features of the highly flexible GN&C architecture and the details of the implemented GN&C algorithms. ANTARES provides a foundation simulation for the Orion Project that has already been successfully used for requirements analysis, system definition analysis, and preliminary GN&C design analysis. ANTARES will find useful application in engineering analysis, mission operations, crew training, avionics-in-the-loop testing, etc. This paper focuses on the entry simulation aspect of ANTARES, which is part of a bigger simulation package supporting the entire mission profile of the Orion vehicle. The unique aspects of entry GN&C design are covered, including how the simulation is being used for Monte Carlo dispersion analysis and for support of linear stability analysis. Sample simulation output from ANTARES is presented in an appendix.

Hoelscher, Brian R.↗

Display analysis with the optimal control model of the human operator

Application of the optimal control model of the human operator to problems in display analysis is discussed. Those aspects of the model pertaining to the operator-display interface and to operator information processing are reviewed and discussed. The techniques are then applied to the analysis of advanced display/control systems for a Terminal Configured Vehicle. Model results are compared with those obtained in a large, fixed-base simulation.

Baron, S.↗

U.S. Civil Rotorcraft Accidents, 1963 through 1997

The U.S. National Transportation Safety Board (NTSB) has recorded 8,436 rotorcraft accidents during the period mid - 1963 through the end of 1997. Review and analysis of the NTSB summary narrative for each accident has been completed. In addition, FAA (Federal Aviation Administration) counts of the growing registered rotorcraft fleet over this period has obtained. Taken together, a large and informative data base is now available, which indicates that the accident rate (on a per airframe basis) has changed very little since the mid 1970s. The data base, even in the summary form provided by this paper, offers suggestions for safer designs and improved flight operations. For analysis purposes, each accident has been placed in one of 21 top level categories as defined by the NTSB. Analysis of this grouping shows that 70 percent of rotorcraft accidents are associated with four categories. The accident count in these top four categories are: (1) 2,408 Loss of engine power (2) 1,322 In flight collision with object (3) 1,114 Loss of control (4) 1,083 Airframe/component/system failure or malfunction. Single engine rotorcraft dominate these accident statistics because of their sheer numbers over the study period. One-third of the loss of engine power accidents with these aircraft is fuel/air mixture related and fuel exhaustion is a common event. This appears to be the case whether a piston or turbine engine is installed. This paper provides similar study results in the other major mishap categories. It shows that both minor and major design and flight operations changes can -- and should -- be made to reduce rotorcraft accidents in the future. The paper outlines these changes and suggests how they may be made.

Harris, Franklin D.↗

Analysis of rocket engine injection combustion processes

A critique is given of the JANNAF sub-critical propellant injection/combustion process analysis computer models and application of the models to correlation of well documented hot fire engine data bases. These programs are the distributed energy release (DER) model for conventional liquid propellants injectors and the coaxial injection combustion model (CICM) for gaseous annulus/liquid core coaxial injectors. The critique identifies model inconsistencies while the computer analyses provide quantitative data on predictive accuracy. The program is comprised of three tasks: (1) computer program review and operations; (2) analysis and data correlations; and (3) documentation.

Salmon, J. W.↗

Space Launch System: SLS Real Time Rollout Monitoring for MPCV

The NASA Space Launch System (SLS) rocket, Orion spacecraft, and Mobile Launcher (ML) are transported to Pad 39B from the Vehicle Assembly Building on a large, tracked vehicle known as the Crawler Transporter (CT). The CT is a holdover from the Apollo and Space Shuttle programs but has been extensively upgraded to accommodate the SLS. The Dynamic Rollout Test (DRT) on March 17, 2022 marked the first full rollout of the SLS and ML. Analysis indicated that loads and vibrations would be well below design limits, but out of an abundance of caution it was decided to monitor the response in real time during the rollout to assure that loads remained within predicted limits. This first rollout was outfitted with extensive test instrumentation such as accelerometers, pressure sensors, and strain gauges. This instrumentation remained in place following the integrated vehicle modal test and was being used for additional Operational Modal Analysis (OMA) during the rollout in addition to the real-time monitoring. This presentation discusses the specific loads and accelerations monitored during the rollout, how and why those responses were chosen, and how the system was implemented. Finally, a post-rollout loads reconstruction is used to assess the process and the analysis tools used for the rollout analysis.

SLS↗