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At least 253 records · Page 14

JETT3: A Holistic, Integrated Analog for Artemis Lunar Surface Exploration

Since 1972, NASA astronauts have performed hundreds of Extravehicular Activities (EVAs) in support of Skylab, Space Shuttle and International Space Station missions. Not since Apollo, however, have EVAs been driven by discovery-based principles of scientific exploration. Upcoming Artemis missions are challenged to build on lessons learned from Apollo, merging 50 years of EVA experience with the planetary science community’s expertise in the remote surface exploration of Mars. The highest-fidelity preparation for Artemis includes both operational and scientific underpinning to represent the complete, complex picture of lunar surface operations. The Joint EVA & Human Surface Mobility Test Team (JETT) is an interdisciplinary team providing such an environment for collaborative analog testing. JETT builds upon prior analog campaigns (e.g., [1, 2]) to provide high-fidelity environments for hardware and concept of operations development. Sponsored by the NASA EVA & Human Surface Mobility Program (EHP), JETT includes representatives from EHP, NASA Engineering, the Science Mission Directorate (SMD), Human Health & Performance, and the Flight Operations Directorate (FOD). JETT tests evaluate NASA reference designs for EVA (e.g., suits and tools), address gaps and risks for Artemis lunar surface operations, develop capabilities for EVA and science tasks, enable technology maturation, and provide training for Artemis EVA operations. JETT3, the final JETT field test of FY22, occurred Oct 3-11, 2022 in the San Francisco Volcanic Field north of Flagstaff, AZ. The test focused on developing the Artemis concept of operations and systems, including integrating an Artemis-like Science Team into a NASA Flight Control Team (FCT) to plan and execute a series of simulated lunar EVAs in an environment analogous to Artemis 3.

T. E. Caswell↗

Elements of Engineering Excellence

The inspiration for this Contract Report (CR) originated in discussions with the director of Marshall Space Flight Center (MSFC) Engineering who asked that we investigate the question: "How do you achieve excellence in aerospace engineering?" Engineering a space system is a complex activity. Avoiding its inherent potential pitfalls and achieving a successful product is a challenge. This CR presents one approach to answering the question of how to achieve Engineering Excellence. We first investigated the root causes of NASA major failures as a basis for developing a proposed answer to the question of Excellence. The following discussions integrate a triad of Technical Understanding and Execution, Partnership with the Project, and Individual and Organizational Culture. The thesis is that you must focus on the whole process and its underlying culture, not just on the technical aspects. In addition to the engineering process, emphasis is given to the need and characteristics of a Learning Organization as a mechanism for changing the culture.

Blair, J. C.↗

Flat H Frangible Joint Evolution

Space vehicle staging and separation events require pyrotechnic devices. They are single-use mechanisms that cannot be tested, nor can failure-tolerant performance be demonstrated in actual flight articles prior to flight use. This necessitates the implementation of a robust design and test approach coupled with a fully redundant, failure-tolerant explosive mechanism to ensure that the system functions even in the event of a single failure. Historically, NASA has followed the single failure-tolerant (SFT) design philosophy for all human-rated spacecraft, including the Space Shuttle Program. Following the end of this program, aerospace companies proposed building the next generation human-rated vehicles with off-the-shelf, non-redundant, zero-failure-tolerant (ZFT) separation systems. Currently, spacecraft and launch vehicle providers for both the Orion and Commercial Crew Programs (CCPs) plan to deviate from the heritage safety approach and NASA's SFT human rating requirements. Both programs' partners have base-lined ZFT frangible joints for vehicle staging and fairing separation. These joints are commercially available from pyrotechnic vendors. Non-human-rated missions have flown them numerous times. The joints are relatively easy to integrate structurally within the spacecraft. In addition, the separation event is debris free, and the resultant pyro shock is lower than that of other design solutions. It is, however, a serious deficiency to lack failure tolerance. When used for critical applications on human-rated vehicles, a single failure could potentially lead to loss of crew (LOC) or loss of mission (LOM)). The Engineering and Safety & Mission Assurance directorates within the NASA Johnson Space Center took action to address this safety issue by initiating a project to develop a fully redundant, SFT frangible joint design, known as the Flat H. Critical to the ability to retrofit on launch vehicles being developed, the SFT mechanisms must fit within the same three-dimensional envelope as current designs as well as meet structural loads requirements. There is increased mass associated with the redundant design, and the goal is to minimize the weight impact as much as possible. These requirements presented significant challenges, both technically and financially; these challenges will be explored in this paper. Perhaps greater than the technical issues confronted during this design process, were the financial considerations. These were a significant part of the story of this design and development plan. Insufficient financial and labor resources were formidable barriers to completing this project. Nevertheless, JSC personnel successfully conducted several test series at JSC with very useful results. The many lessons learned drove design improvements, performance efficiency, and increased functional reliability. This paper examines the significant technical and financial challenges that these requirements posed to the project team. It discusses the evolution of the SFT frangible joint design, including optimization, testing, and successful partnering of the Johnson Space Center (JSC) engineering and JSC safety organizations, to enhance the flight safety margin for America's next generation of human-rated space vehicles.

Diegelman, Thomas E.↗

Energy Production Through Anaerobic Digestion in the Food-Waste-Energy Nexus

The addition of a second anaerobic digestion process at Landis Sewerage Authority (LSA) in Vineland, N.J., was a project designed to accomplish several major objectives. First, it would replace an inactive digester that Landis had been “cannibalizing” for parts to keep its primary digester operating. Second, and more importantly to the New Jersey Department of Agriculture, this project provided an opportunity to create a tangible, working apparatus to demonstrate whether food waste and manure (provided by food processors and farmers) could be used efficiently and effectively to create gas used to power a co-generation unit that supplies electrical power to run the Authority’s sewage-treatment operations. Additionally, the project would further test an additive (BAE) for its effects on overall gas production. NJDA specifically sought to avoid using the grant funds for a feasibility study that did not result in a working demonstration project, and that goal was met by producing an actual second digestion process at Landis. Finally, this project provided the opportunity to demonstrate how the re-use and re-purposing of existing infrastructure could help lower the costs of providing an energy-production unit without having to build it from the ground up. A key to achieving those goals was limiting the use of outside contractors to build the digestion process. Instead, LSA employed the engineering services of its executive director and another employee to design the project, and the talents of its in-house employees to construct and install components of the digestion process. This minimized expenditures for outside providers while also enabling LSA to have greater control over both the design and construction. Those controls on costs enabled a full fact-finding mission to similar operations in Ohio and Indiana in August 2015. The visits allowed comparisons that found the Midwest operations (at least at two of the three locations) were less constrained by odor control issues than Landis is under New Jersey environmental regulations, and that the Fair Oaks Dairy Farm in Indiana had successfully incorporated its digester operation into its wide-ranging and popular “farm experience” attraction that includes restaurants, stores selling products from the farm’s output, tours of massive robotic milking parlors and a visitors’ center featuring “4D movies” about dairy farming and the use of manure in creating energy. The visit to Fair Oaks allowed the NJDA/Landis team to also examine whether a Fair Oaks “farm experience” model could be replicated in the Mid-Atlantic region, with its higher density of population, given the need for additional odor-control components to account for the closer proximity to population centers, but also benefiting from a larger potential close-in visitor base. Again, by streamlining the fact-finding process and using ground transportation instead of airfare, the travel line-item of the project budget was essentially halved. That enabled the creation of a video about the Landis project, which can be sent electronically – “e-travel,” so to speak – to other states and agencies that want to learn more about what was created in Vineland.

09 BIOMASS FUELS↗

Los Alamos National Laboratory Release of Cesium-137 Corrective Action Plan

This Corrective Action Plan (CAP) was developed by a team chartered by John Sarrao, Deputy Director for Science, Technology, and Engineering (DDSTE), to review and respond to the findings of the Joint National Nuclear Security Administration/Triad National Security (NNSA/Triad) Investigation Team (JIT) Joint Investigation Report for the “Sealed Source Recovery at the University of Washington Harborview Training and Research Facility Results in Release of Cesium-137 on May 2, 2019,” dated March 30, 2020. On May 2, 2019, International Isotopes, Inc. (INIS), a subcontractor to Triad National Security, LLC, inadvertently breached a sealed cesium-137 source at the University of Washington (UW), Harborview Medical Center Research and Training (HRT) building in downtown Seattle while attempting to recover the source for the National Nuclear Security Administration (NNSA) Off-Site Source Recovery Program (OSRP). The source breach resulted in contamination of personnel and the HRT building, as well as a release of radioactive material to the environment

07 ISOTOPE AND RADIATION SOURCES↗

DDSTE Lab Overview March 2021 [Slides]

An overview of Los Alamos National Laboratory is given, primarily related to the Deputy Director of Science, Technology and Engineering (DDSTE) perspective.

42 ENGINEERING↗

Flight evaluation of advanced control systems and displays on a general aviation airplane

A flight-test program was conducted to determine the effect of advanced flight control systems and displays on the handling qualities of a light twin-engined airplane. A flight-director display and an attitude-command control system, used separately and in combination, transformed a vehicle with poor handling qualities during ILS approaches in turbulent air into a vehicle with good handling qualities. The attitude-command control system also improved the ride qualities of the airplane. A rate-command control system made only small improvements to the airplane's ILS handling qualities in turbulence. Both the rate- and the attitude-command control systems reduced stall warning in the test airplane, increasing the likelihood of inadvertent stalls. The final approach to the point of flare was improved by both the rate- and the attitude-command control systems. However, the small control wheel deflections necessary to flare were unnatural and tended to cause overcontrolling during flare. Airplane handling qualities are summarized for each control-system and display configuration.

Loschke, P. C.↗

EVA tools and equipment reference book

This document contains a mixture of tools and equipment used throughout the space shuttle-based extravehicular activity (EVA) program. Promising items which have reached the prototype stage of development are also included, but should not be considered certified ready for flight. Each item is described with a photo, a written discussion, technical specifications, dimensional drawings, and points of contact for additional information. Numbers on the upper left-hand corner of each photo may be used to order specific pictures from NASA and contractor photo libraries. Points of contact were classified as either operational or technical. An operational contact is an engineer from JSC Mission Operations Directorate who is familiar with the basic function and on-orbit use of the tool. A technical contact would be the best source of detailed technical specifications and is typically the NASA subsystem manager. The technical information table for each item uses the following terms to describe the availability or status of each hardware item: Standard - Flown on every mission as standard manifest; Flight specific - Potentially available for flight, not flown every mission (flight certification cannot be guaranteed and recertification may be required); Reference only - Item no longer in active inventory or not recommended for future use, some items may be too application-specific for general use; and Developmental - In the prototype stage only and not yet available for flight. The current availability and certification of any flight-specific tool should be verified with the technical point of contact. Those tools built and fit checked for Hubble Space Telescope maintenance are program dedicated and are not available to other customers. Other customers may have identical tools built from the existing, already certified designs as an optional service.

Fullerton, R. K.↗

The National Aerospace Initiative (NAI): Technologies For Responsive Space Access

The Secretary of Defense has set new goals for the Department of Defense (DOD) to transform our nation's military forces. The Director for Defense Research and Engineering (DDR&E) has responded to this challenge by defining and sponsoring a transformational initiative in Science and Technology (S&T) - the National Aerospace Initiative (NAI) - which will have a fundamental impact on our nation's military capabilities and on the aerospace industry in general. The NAI is planned as a joint effort among the tri-services, DOD agencies and National Aeronautics and Space Administration (NASA). It is comprised of three major focus areas or pillars: 1) High Speed Hypersonics (HSH), 2) Space Access (SA), and 3) Space Technology (ST). This paper addresses the Space Access pillar. The NAI-SA team has employed a unique approach to identifying critical technologies and demonstrations for satisfying both military and civilian space access capabilities needed in the future. For planning and implementation purposes the NAI-SA is divided into five technology subsystem areas: Airframe, Propulsion, Flight Subsystems, Operations and Payloads. Detailed technology roadmaps were developed under each subsystem area using a time-phased, goal oriented approach that provides critical space access capabilities in a timely manner and involves subsystem ground and flight demonstrations. This S&T plan addresses near-term (2009), mid-term (2016), and long-term (2025) goals and objectives for space access. In addition, system engineering and integration approach was used to make sure that the plan addresses the requirements of the end users. This paper describes in some detail the technologies in NAI-Space Access pillar. Some areas of emphasis are: high temperature materials, thermal protection systems, long life, lightweight, highly efficient airframes, metallic and composite cryotanks, advanced liquid rocket engines, integrated vehicle health monitoring and management, highly operable systems and payloads. Implementation strategies for NAI are also described.

Culbertson, Andrew↗

X-43D Conceptual Design and Feasibility Study

NASA s Next Generation Launch Technology (NGLT) Program, in conjunction with the office of the Director of Defense Research and Engineering (DDR&E), developed an integrated hypersonic technology demonstration roadmap. This roadmap is an integral part of the National Aerospace Initiative (NAI), a multi-year, multi-agency cooperative effort to invest in and develop, among other things, hypersonic technologies. This roadmap contains key ground and flight demonstrations required along the path to developing a reusable hypersonic space access system. One of the key flight demonstrations required for systems that will operate in the high Mach number regime is the X-43D. As currently conceived, the X-43D is a Mach 15 flight test vehicle that incorporates a hydrogen-fueled scramjet engine. The purpose of the X-43D is to gather high Mach number flight environment and engine operability information which is difficult, if not impossible, to gather on the ground. During 2003, the NGLT Future Hypersonic Flight Demonstration Office initiated a feasibility study on the X-43D. The objective of the study was to develop a baseline conceptual design, assess its performance, and identify the key technical issues. The study also produced a baseline program plan, schedule, and cost, along with a list of key programmatic risks.

Johnson, Donald B.↗

Constellation Program Life-cycle Cost Analysis Model (LCAM)

The Constellation Program (CxP) is NASA's effort to replace the Space Shuttle, return humans to the moon, and prepare for a human mission to Mars. The major elements of the Constellation Lunar sortie design reference mission architecture are shown. Unlike the Apollo Program of the 1960's, affordability is a major concern of United States policy makers and NASA management. To measure Constellation affordability, a total ownership cost life-cycle parametric cost estimating capability is required. This capability is being developed by the Constellation Systems Engineering and Integration (SE&I) Directorate, and is called the Lifecycle Cost Analysis Model (LCAM). The requirements for LCAM are based on the need to have a parametric estimating capability in order to do top-level program analysis, evaluate design alternatives, and explore options for future systems. By estimating the total cost of ownership within the context of the planned Constellation budget, LCAM can provide Program and NASA management with the cost data necessary to identify the most affordable alternatives. LCAM is also a key component of the Integrated Program Model (IPM), an SE&I developed capability that combines parametric sizing tools with cost, schedule, and risk models to perform program analysis. LCAM is used in the generation of cost estimates for system level trades and analyses. It draws upon the legacy of previous architecture level cost models, such as the Exploration Systems Mission Directorate (ESMD) Architecture Cost Model (ARCOM) developed for Simulation Based Acquisition (SBA), and ATLAS. LCAM is used to support requirements and design trade studies by calculating changes in cost relative to a baseline option cost. Estimated costs are generally low fidelity to accommodate available input data and available cost estimating relationships (CERs). LCAM is capable of interfacing with the Integrated Program Model to provide the cost estimating capability for that suite of tools.

Prince, Andy↗

Air Data Boom System Development for the Max Launch Abort System (MLAS) Flight Experiment

In 2007, the NASA Exploration Systems Mission Directorate (ESMD) chartered the NASA Engineering Safety Center (NESC) to demonstrate an alternate launch abort concept as risk mitigation for the Orion project's baseline "tower" design. On July 8, 2009, a full scale and passively, aerodynamically stabilized MLAS launch abort demonstrator was successfully launched from Wallops Flight Facility following nearly two years of development work on the launch abort concept: from a napkin sketch to a flight demonstration of the full-scale flight test vehicle. The MLAS flight test vehicle was instrumented with a suite of aerodynamic sensors. The purpose was to obtain sufficient data to demonstrate that the vehicle demonstrated the behavior predicted by Computational Fluid Dynamics (CFD) analysis and wind tunnel testing. This paper describes development of the Air Data Boom (ADB) component of the aerodynamic sensor suite.

Woods-Vedeler, Jessica A.↗

Design and Analysis of Outer Mold Line Close-outs for the Max Launch Abort System (MLAS) Flight Experiment

In 2007, the NASA Exploration Systems Mission Directorate (ESMD) chartered the NASA Engineering Safety Center (NESC) to demonstrate an alternate launch abort concept as risk mitigation for the Orion project's baseline "tower" design. On July 8, 2009, a full scale, passive aerodynamically stabilized Max Launch Abort System (MLAS) pad abort demonstrator was successfully launched from NASA Goddard Space Flight Center's Wallops Flight Facility. Aerodynamic close-outs were required to cover openings on the MLAS fairing to prevent aerodynamic flow-through and to maintain the MLAS OML surface shape. Two-ply duct tape covers were designed to meet these needs. The duct tape used was a high strength fiber reinforced duct tape with a rubberized adhesive that demonstrated 4.6 lb/in adhesion strength to the unpainted fiberglass fairing. Adhesion strength was observed to increase as a function of time. The covers were analyzed and experimentally tested to demonstrate their ability to maintain integrity under anticipated vehicle ascent pressure loads and to not impede firing of the drogue chute mortars. Testing included vacuum testing and a mortar fire test. Tape covers were layed-up on thin Teflon sheets to facilitate installation on the vehicle. Custom cut foam insulation board was used to fill mortar hole and separation joint cavities and provide support to the applied tape covers. Flight test results showed that the tape covers remained adhered during flight.

Woods-Vedeler, Jessica A.↗

Validation of High-Fidelity CFD Simulations for Rocket Injector Design

Computational fluid dynamics (CFD) has the potential to improve the historical rocket injector design process by evaluating the sensitivity of performance and injector-driven thermal environments to the details of the injector geometry and key operational parameters. Methodical verification and validation efforts on a range of coaxial injector elements have shown the current production CFD capability must be improved in order to quantitatively impact the injector design process. This paper documents the status of a focused effort to compare and understand the predictive capabilities and computational requirements of a range of CFD methodologies on a set of single element injector model problems. The steady Reynolds-Average Navier-Stokes (RANS), unsteady Reynolds-Average Navier-Stokes (URANS) and three different approaches using the Large Eddy Simulation (LES) technique were used to simulate the initial model problem, a single element coaxial injector using gaseous oxygen and gaseous hydrogen propellants. While one high-fidelity LES result matches the experimental combustion chamber wall heat flux very well, there is no monotonic convergence to the data with increasing computational tool fidelity. Systematic evaluation of key flow field regions such as the flame zone, the head end recirculation zone and the downstream near wall zone has shed significant, though as of yet incomplete, light on the complex, underlying causes for the performance level of each technique. 1 Aerospace Engineer and Combustion CFD Team Leader, MS ER42, NASA MSFC, AL 35812, Senior Member, AIAA. 2 Professor and Director, Computational Combustion Laboratory, School of Aerospace Engineering, 270 Ferst Dr., Atlanta, GA 30332, Associate Fellow, AIAA. 3 Reilly Professor of Engineering, School of Mechanical Engineering, 585 Purdue Mall, West Lafayette, IN 47907, Fellow, AIAA. 4 Principal Member of Technical Staff, Combustion Research Facility, 7011 East Avenue, MS9051, Livermore, CA 94550, Associate Fellow, AIAA. 5 J. L. and G. H. McCain Endowed Chair, Mechanical Engineering, 104 Research Building East, University Park, PA 16802, Fellow, AIAA. American Institute of Aeronautics and Astronautics 1

Tucker, P. Kevin↗

SACD's Support of the Hyper-X Program

NASA s highly successful Hyper-X program demonstrated numerous hypersonic air-breathing vehicle related technologies including scramjet performance, advanced materials and hot structures, GN&C, and integrated vehicle performance resulting in, for the first time ever, acceleration of a vehicle powered by a scramjet engine. The Systems Analysis and Concepts Directorate (SACD) at NASA s Langley Research Center played a major role in the integrated team providing critical support, analysis, and leadership to the Hyper-X Program throughout the program s entire life and were key to its ultimate success. Engineers in SACD s Vehicle Analysis Branch (VAB) were involved in all stages and aspects of the program, from conceptual design prior to contract award, through preliminary design and hardware development, and in to, during, and after each of the three flights. Working closely with other engineers at Langley and Dryden, as well as industry partners, roughly 20 members of SACD were involved throughout the evolution of the Hyper-X program in nearly all disciplines, including lead roles in several areas. Engineers from VAB led the aerodynamic database development, the propulsion database development, and the stage separation analysis and database development effort. Others played major roles in structures, aerothermal, GN&C, trajectory analysis and flight simulation, as well as providing CFD support for aerodynamic, propulsion, and aerothermal analysis.

Robinson, Jeffrey S.↗

STS-1: Columbia Briefings

A video presentation on an update of the STS-1 Columbia Shuttle is shown. Hugh Harris is the moderator. He introduces Don Phillips, Chief STS Test OPS, who presents the status of the vehicle. Terry William, Chief of Mechanical Systems, discusses the debonding of the panels. A question and answer period from the news media is shown. The various topics of discussion from the news media include: 1) Repair of thermal tiles; 2) Launch dates; and 3) Landing and launch sites and 4) Low pressure/high pressure tanking tests. An audio presentation is given of questions from NASA Marshall Space Flight Center and NASA Washington. On March 12, 1981, another STS-1 Columbia update is shown. Bob Schick, Shuttle Test Director, and Bob Sieck, Flight Project Engineer answers questions about the actual repair time of the panels and a very detailed description of the three areas of debonding is presented. A brief launch date statement from Dr. Allen Lovelace, Acting NASA Administrator is given and John Lardley, Shuttle Associate Director, discusses the flight readiness review.

Source record↗

Composite Overwrapped Pressure Vessel (COPV) Damage Tolerance Life Analysis Methodology and Test Best Practices

The NASA Engineering and Safety Center (NESC) Deputy Director requested an independent assessment to develop data to understand the limitations of linear elastic fracture mechanics (LEFM) computational methods used to predict fatigue crack growth rate (da/dN) behavior of small detectable cracks in thin metal liners for composite overwrapped pressure vessels (COPVs). The NESC assessment team was also requested to demonstrate a test-based methodology for validating damage tolerance requirements for COPVs with elastically responding metal liners where LEFM methods are not appropriate. This report contains the outcome of the NESC assessment.

Composite Overwrapped Pressure Vessels; Linear Ela↗