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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.

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At least 325 records · Page 18

Z-Pinch Pulsed Plasma Propulsion Technology Development

Fusion-based propulsion can enable fast interplanetary transportation. Magneto-inertial fusion (MIF) is an approach which has been shown to potentially lead to a low cost, small reactor for fusion break even. The Z-Pinch/dense plasma focus method is an MIF concept in which a column of gas is compressed to thermonuclear conditions by an axial current (I approximates 100 MA). Recent advancements in experiments and the theoretical understanding of this concept suggest favorable scaling of fusion power output yield as I(sup 4). This document presents a conceptual design of a Z-Pinch fusion propulsion system and a vehicle for human exploration. The purpose of this study is to apply Z-Pinch fusion principles to the design of a propulsion system for an interplanetary spacecraft. This study took four steps in service of that objective; these steps are identified below. 1. Z-Pinch Modeling and Analysis: There is a wealth of literature characterizing Z-Pinch physics and existing Z-Pinch physics models. In order to be useful in engineering analysis, simplified Z-Pinch fusion thermodynamic models are required to give propulsion engineers the quantity of plasma, plasma temperature, rate of expansion, etc. The study team developed these models in this study. 2. Propulsion Modeling and Analysis: While the Z-Pinch models characterize the fusion process itself, propulsion models calculate the parameters that characterize the propulsion system (thrust, specific impulse, etc.) The study team developed a Z-Pinch propulsion model and used it to determine the best values for pulse rate, amount of propellant per pulse, and mixture ratio of the D-T and liner materials as well as the resulting thrust and specific impulse of the system. 3. Mission Analysis: Several potential missions were studied. Trajectory analysis using data from the propulsion model was used to determine the duration of the propulsion burns, the amount of propellant expended to complete each mission considered. 4. Vehicle Design: To understand the applicability of Z-Pinch propulsion to interplanetary travel, it is necessary to design a concept vehicle that uses it -- the propulsion system significantly impacts the design of the electrical, thermal control, avionics and structural subsystems of a vehicle. The study team developed a conceptual design of an interplanetary vehicle that transports crew and cargo to Mars and back and can be reused for other missions. Several aspects of this vehicle are based on a previous crewed fusion vehicle study -- the Human Outer Planet Exploration (HOPE) Magnetized Target Fusion (MTF) vehicle. Portions of the vehicle design were used outright and others were modified from the MTF design in order to maintain comparability.

Polsgrove, Tara↗

Exploration Space Suit Architecture and Destination Environmental-Based Technology Development

This paper continues forward where EVA Space Suit Architecture: Low Earth Orbit Vs. Moon Vs. Mars left off in the development of a space suit architecture that is modular in design and could be reconfigured prior to launch or during any given mission depending on the tasks or destination. This space suit system architecture and technologies required based on human exploration (EVA) destinations will be discussed, and how these systems should evolve to meet the future exploration EVA needs of the US human space flight program. A series of exercises and analyses provided a strong indication that the Constellation Program space suit architecture, with its maximum reuse of technology and functionality across a range of mission profiles and destinations, is postured to provide a viable solution for future space exploration missions. The destination environmental analysis demonstrates that the modular architecture approach could provide the lowest mass and mission cost for the protection of the crew, given any human mission outside of low-Earth orbit. Additionally, some of the high-level trades presented here provide a review of the environmental and nonenvironmental design drivers that will become increasingly important as humans venture farther from Earth. The presentation of destination environmental data demonstrates a logical clustering of destination design environments that allows a focused approach to technology prioritization, development, and design that will maximize the return on investment, largely independent of any particular design reference mission.

Hill, Terry R.↗

Using Knowledge-Based Systems to Support Learning of Organizational Knowledge: A Case Study

This paper describes the deployment of a knowledge system to support learning of organizational knowledge at the Jet Propulsion Laboratory (JPL), a US national research laboratory whose mission is planetary exploration and to 'do what no one has done before.' Data collected over 19 weeks of operation were used to assess system performance with respect to design considerations, participation, effectiveness of communication mechanisms, and individual-based learning. These results are discussed in the context of organizational learning research and implications for practice.

knowledge management↗

Evolution of the Space Shuttle Primary Avionics Software and Avionics for Shuttle Derived Launch Vehicles

As a result of recommendation from the Augustine Panel, the direction for Human Space Flight has been altered from the original plan referred to as Constellation. NASA s Human Exploration Framework Team (HEFT) proposes the use of a Shuttle Derived Heavy Lift Launch Vehicle (SDLV) and an Orion derived spacecraft (salvaged from Constellation) to support a new flexible direction for space exploration. The SDLV must be developed within an environment of a constrained budget and a preferred fast development schedule. Thus, it has been proposed to utilize existing assets from the Shuttle Program to speed development at a lower cost. These existing assets should not only include structures such as external tanks or solid rockets, but also the Flight Software which has traditionally been a "long pole" in new development efforts. The avionics and software for the Space Shuttle was primarily developed in the 70 s and considered state of the art for that time. As one may argue that the existing avionics and flight software may be too outdated to support the new SDLV effort, this is a fallacy if they can be evolved over time into a "modern avionics" platform. The technology may be outdated, but the avionics concepts and flight software algorithms are not. The reuse of existing avionics and software also allows for the reuse of development, verification, and operations facilities. The keyword is evolve in that these assets can support the fast development of such a vehicle, but then be gradually evolved over time towards more modern platforms as budget and schedule permits. The "gold" of the flight software is the "control loop" algorithms of the vehicle. This is the Guidance, Navigation, and Control (GNC) software algorithms. This software is typically the most expensive to develop, test, and verify. Thus, the approach is to preserve the GNC flight software, while first evolving the supporting software (such as Command and Data Handling, Caution and Warning, Telemetry, etc.). This can be accomplished by gradually removing the "support software" from the legacy flight software leaving only the GNC algorithms. The "support software" could be re-developed for modern platforms, while leaving the GNC algorithms to execute on technology compatible with the legacy system. It is also possible to package the GNC algorithms into an emulated version of the original computer (via Field Programmable Gate Arrays or FPGAs), thus becoming a "GNC on a Chip" solution where it could live forever to be embedded in modern avionics platforms.

Ferguson, Roscoe C.↗

Laserfax

The photo shows an Associated Press technician receiving a photograph prepared by means of a high speed, high resolution facsimile system known as Laserfax, so called because it employs a laser beam to scan the photo being sent. Laser scanning data is converted to electrical signals and transmitted to news bureaus within the Associated Press network via microwave radio or telephone lines. At the other end, another laser sweeps reconverted imagery onto a special, light-sensitive, dry silver paper. The paper is then heat processed to reproduce the photograph. Manufactured by Harris Electronics Systems Inc., Melbourne, Florida, Laserfax incorporates NASA thermal control coating technology developed by Jet Propulsion Laboratory for use on spacecraft antennas; the coatings block absorption of solar radiation which would interfere with the antenna's proper operation. Harris Electronics Systems, originally Radiation, Inc., reused the NASA technology in development of Laserfax. A NASA technical support package provided information about the thermal properties that could be expected of various coatings for the facsimile system's paper rollers; this information served as a design base for the infrared heat source used in developing the photo. Although relatively new, Laserfax is in extensive service. It is manufactured in several models. One of them is the type used by the Associated Press, its news bureaus and affiliated newspapers, radio and television stations. Other models have been sold in large numbers to law enforcement agencies for transmitting high quality fingerprints and identification photos. Laserfax is also in service with the National Weather Service, which converts satellite imagery to weather photographs and relays them to local weather stations, television stations, newspapers and airlines.

Source record↗

Solid Rocket Booster (SRB) - Evolution and Lessons Learned During the Shuttle Program

The Solid Rocket Booster (SRB) element integrates all the subsystems needed for ascent flight, entry, and recovery of the combined Booster and Motor system. These include the structures, avionics, thrust vector control, pyrotechnic, range safety, deceleration, thermal protection, and retrieval systems. This represents the only human-rated, recoverable and refurbishable solid rocket ever developed and flown. Challenges included subsystem integration, thermal environments and severe loads (including water impact), sometimes resulting in hardware attrition. Several of the subsystems evolved during the program through design changes. These included the thermal protection system, range safety system, parachute/recovery system, and others. Obsolescence issues occasionally required component recertification. Because the system was recovered, the SRB was ideal for data and imagery acquisition, which proved essential for understanding loads and system response. The three main parachutes that lower the SRBs to the ocean are the largest parachutes ever designed, and the SRBs are the largest structures ever to be lowered by parachutes. SRB recovery from the ocean was a unique process and represented a significant operational challenge; requiring personnel, facilities, transportation, and ground support equipment. The SRB element achieved reliability via extensive system testing and checkout, redundancy management, and a thorough postflight assessment process. Assembly and integration of the booster subsystems was a unique process and acceptance testing of reused hardware components was required for each build. Extensive testing was done to assure hardware functionality at each level of stage integration. Because the booster element is recoverable, subsystems were available for inspection and testing postflight, unique to the Shuttle launch vehicle. Problems were noted and corrective actions were implemented as needed. The postflight assessment process was quite detailed and a significant portion of flight operations. The SRBs provided fully redundant critical systems including thrust vector control, mission critical pyrotechnics, avionics, and parachute recovery system. The design intent was to lift off with full redundancy. On occasion, the redundancy management scheme was needed during flight operations. This paper describes some of the design challenges, how the design evolved with time, and key areas where hardware reusability contributed to improved system level understanding.

Kanner, Howard S.↗

Core Stage TVC Systems Engineering Challenges in Reusing Heritage Hardware

The Space Launch System (SLS) Core Stage (CS) Thrust Vector Control (TVC) system is comprised of 8 mechanical feedback Shuttle heritage Type III TVC actuators and four RS-25 engines, each attached to a Shuttle heritage gimbal block/bearing. Two actuators are used to move each engine in two planes perpendicular to one another (i.e., pitch and yaw). The TVC system design leverages hardware from the Space Shuttle program as well as new hardware designed specifically for the Core Stage. The Space Shuttle heritage hardware directly reused on SLS includes the Orbiter TVC hydraulic servo-actuators (with two slight design modifications), the Orbiter hydraulic circulation pumps, the Orbiter gimbal block/bearing, and the Solid Rocket Booster hydraulic pumps. The Core Auxiliary Power Unit (CAPU) is derived from the Orbiter Auxiliary Power Unit (APU). The Orbiter and Solid Rocket Booster APU turbines are powered by hot gas produced by catalyzed hydrazine decomposition. On the SLS Core Stage, the CAPU turbine is spun using cold gas tapped-off from the RS-25 to CS liquid hydrogen autogenous pressurization line. While direct reuse or slight modification of existing hardware may seem to be a triple-win for a program in cost, schedule, and technical risk mitigation, those benefits can only be realized when its degree of application in a new system is carefully and thoughtfully managed. The heritage hardware reuse should be prescribed within the heritage design capability and reuse environments must lie within the envelope of heritage qualification testing. Despite the significant test and flight experience of the Shuttle heritage hardware components, successful integration with the newly designed CS TVC components and incorporation into the stage design proved to be a challenge which required re-qualification of the heritage hardware as well as thorough integrated testing to support flight certification. Examples of the challenges that were overcome include: re-qualifying heritage hardware to survive new shock and vibration environments, certifying performance of extensively modified heritage hardware, regenerating design insight due to lack of available heritage vendor data, showing compliance to modern structural design standards, translation of heritage requirements for analog avionics to modern digital avionics, and interfacing heritage mechanical hardware with newly designed avionics. This paper is the second installment in a seven-paper series surveying the design, engineering, test validation, and flight performance of the Core Stage Thrust Vector Control system. This paper will discuss several engineering challenges encountered during the development process for SLS CS TVC and how they were successfully overcome to reach flight readiness.

Thrust Vector Control↗

Space Launch System: Core Stage Thrust Vector Control Systems Engineering Challenges in Reusing Heritage Hardware

The Space Launch System (SLS) Core Stage (CS) Thrust Vector Control (TVC) system is comprised of 8 mechanical feedback Shuttle heritage Type III TVC actuators and four RS-25 engines, each attached to a Shuttle heritage gimbal block/bearing. Two actuators are used to move each engine in two planes perpendicular to one another (i.e., pitch and yaw). The TVC system design leverages hardware from the Space Shuttle program as well as new hardware designed specifically for the Core Stage. The Space Shuttle heritage hardware directly reused on SLS includes the Orbiter TVC hydraulic servo-actuators (with two slight design modifications), the Orbiter hydraulic circulation pumps, the Orbiter gimbal block/bearing, and the Solid Rocket Booster hydraulic pumps. The Core Auxiliary Power Unit (CAPU) is derived from the Orbiter Auxiliary Power Unit (APU). The Orbiter and Solid Rocket Booster APU turbines are powered by hot gas produced by catalyzed hydrazine decomposition. On the SLS Core Stage, the CAPU turbine is spun using cold gas tapped-off from the RS-25 to CS liquid hydrogen autogenous pressurization line. While direct reuse or slight modification of existing hardware may seem to be a triple-win for a program in cost, schedule, and technical risk mitigation, those benefits can only be realized when its degree of application in a new system is carefully and thoughtfully managed. The heritage hardware reuse should be prescribed within the heritage design capability and reuse environments must lie within the envelope of heritage qualification testing. Despite the significant test and flight experience of the Shuttle heritage hardware components, successful integration with the newly designed CS TVC components and incorporation into the stage design proved to be a challenge which required re-qualification of the heritage hardware as well as thorough integrated testing to support flight certification. Examples of the challenges that were overcome include: re-qualifying heritage hardware to survive new shock and vibration environments, certifying performance of extensively modified heritage hardware, regenerating design insight due to lack of available heritage vendor data, showing compliance to modern structural design standards, translation of heritage requirements for analog avionics to modern digital avionics, and interfacing heritage mechanical hardware with newly designed avionics. This paper is the second installment in a seven-paper series surveying the design, engineering, test validation, and flight performance of the Core Stage Thrust Vector Control system. This paper will discuss several engineering challenges encountered during the development process for SLS CS TVC and how they were successfully overcome to reach flight readiness.

Thrust Vector Control↗

A decision-directed network for dual-polarization crosstalk cancellation

Frequency reuse in the specific form of dual-polarized microwave communication systems has grown in importance in recent years as a practical means of radio spectrum conservation. Ideally the capacity of a given frequency allocation can be doubled through dual-polarization. However, hardware imperfections and propagation effects, particularly rain depolarization, prevent the achievement of this doubling without severe system performance degradation. A decision-directed cross-polarization correction network is presented whose operation depends on only simple base-band signal processing. No pilot tones or frequency offsets are required. The loop can work with any two-dimensional signal set for digital data transmission. The loop has been experimentally verified and provides a means of doubling the data capacity with little performance degradation.

Weber, W. J., III↗

Thermal characterization of reusable external insulation for the space shuttle.

Thermal protection systems utilizing reusable ceramic external insulations are under study for application to the orbiter vehicle of NASA's space shuttle system which is to be launched by an expendable booster, remain in orbit for a week or two, reenter the earth's atmosphere, and land like a conventional aircraft. The required reuse capability is for 100 missions. The thermal characterization of the reusable external insulation (REI) is described. Thermal conductivity measurements are described for a series of mullite-based REIs with densities ranging from 100 to 300 kg/cu m, including opacified variations of the mullite material designed for reduction of the radiant component of heat transport. The results of thermal conductivity measurements performed on guarded-hot-plate equipment from 150 to above 1200 K in different vacuum and gaseous environments are described. Measurements were also made with exceptionally large temperature differences to detect transparency effects in the unopacified REIs. These measurements were made to provide design data for the flight conditions, and to aid in theoretical computations aimed at separating and optimizing the heat transport components.

Brazel, J. P.↗

Inactivation of a model coliphage virus in water by iodine

Until now, NASA's space water reuse research program has not considered the transport of water-borne infectious enteric viruses; however, viral diseases probably are a signifficant concern in long-duration space missions. To simplify monitoring and prediction of pathogen distribution, model indicator strains historically have been used. In this research, the male specific RNA coliphage MS-2 is used as a model of enteric viruses due to their similar size and biochemical composition. Inactivation of some water-borne enteric viruses by iodine has previously been characterized. In this paper, iodine inactivation of the model coliphage MS-2 in buffered water is compared with earlier bench-scale disinfection survival data and with survival in iodinated simulated shower water used in a test water recycling system.

Brion, Gail M.↗

Distributed earth model/orbiter simulation

Distributed Earth Model/Orbiter Simulation (DEMOS) is a network based application developed for the UNIX environment that visually monitors or simulates the Earth and any number of orbiting vehicles. Its purpose is to provide Mission Control Center (MCC) flight controllers with a visually accurate three dimensional (3D) model of the Earth, Sun, Moon and orbiters, driven by real time or simulated data. The project incorporates a graphical user interface, 3D modelling employing state-of-the art hardware, and simulation of orbital mechanics in a networked/distributed environment. The user interface is based on the X Window System and the X Ray toolbox. The 3D modelling utilizes the Programmer's Hierarchical Interactive Graphics System (PHIGS) standard and Raster Technologies hardware for rendering/display performance. The simulation of orbiting vehicles uses two methods of vector propagation implemented with standard UNIX/C for portability. Each part is a distinct process that can run on separate nodes of a network, exploiting each node's unique hardware capabilities. The client/server communication architecture of the application can be reused for a variety of distributed applications.

Geisler, Erik↗

Integrated Circuit Chip Improves Network Efficiency

Prior to 1999 and the development of SpaceWire, a standard for high-speed links for computer networks managed by the European Space Agency (ESA), there was no high-speed communications protocol for flight electronics. Onboard computers, processing units, and other electronics had to be designed for individual projects and then redesigned for subsequent projects, which increased development periods, costs, and risks. After adopting the SpaceWire protocol in 2000, NASA implemented the standard on the Swift mission, a gamma ray burst-alert telescope launched in November 2004. Scientists and developers on the James Webb Space Telescope further developed the network version of SpaceWire. In essence, SpaceWire enables more science missions at a lower cost, because it provides a standard interface between flight electronics components; new systems need not be custom built to accommodate individual missions, so electronics can be reused. New protocols are helping to standardize higher layers of computer communication. Goddard Space Flight Center improved on the ESA-developed SpaceWire by enabling standard protocols, which included defining quality of service and supporting plug-and-play capabilities. Goddard upgraded SpaceWire to make the routers more efficient and reliable, with features including redundant cables, simultaneous discrete broadcast pulses, prevention of network blockage, and improved verification. Redundant cables simplify management because the user does not need to worry about which connection is available, and simultaneous broadcast signals allow multiple users to broadcast low-latency side-band signal pulses across the network using the same resources for data communication. Additional features have been added to the SpaceWire switch to prevent network blockage so that more robust networks can be designed. Goddard s verification environment for the link-and-switch implementation continuously randomizes and tests different parts, constantly anticipating situations, which helps improve communications reliability. It has been tested in many different implementations for compatibility.

Source record↗

Further Characterization of CELSS Wastes: A Review of Solid Wastes Present to Support Potential Secondary Biomass Production

Controlled ecological life support systems (CELSS) may one day play an essential role in extraterrestrial colonies. Key to the success of any CELSS will be the system's ability to approach a self-supporting status through recovery and reuse of basic resources. Primary CELSS solid wastes with potential to support secondary biomass production will be inedible plant biomass and metabolic human wastes. Solid waste production is summarized and reported as 765 g N per day per person, including 300 g C and 37 g N per day per person. One Resource Recovery configuration using the bioprocessing of solid wastes into a Tilapia feed stream is examined. Based on estimated conversion efficiencies, 12 g of protein per day per person is produced as a nutrition supplement. The unique tissue composition of crops produced at the Kennedy Space Center CELSS Program highlights the need to evaluate Resource Recovery components with data generated in the CELSS environment.

Muller, Matthew S.↗

Evolving the Reuse Process at the Flight Dynamics Division (FDD) Goddard Space Flight Center

This paper presents the interim results from the Software Engineering Laboratory's (SEL) Reuse Study. The team conducting this study has, over the past few months, been studying the Generalized Support Software (GSS) domain asset library and architecture, and the various processes associated with it. In particular, we have characterized the process used to configure GSS-based attitude ground support systems (AGSS) to support satellite missions at NASA's Goddard Space Flight Center. To do this, we built detailed models of the tasks involved, the people who perform these tasks, and the interdependencies and information flows among these people. These models were based on information gleaned from numerous interviews with people involved in this process at various levels. We also analyzed effort data in order to determine the cost savings in moving from actual development of AGSSs to support each mission (which was necessary before GSS was available) to configuring AGSS software from the domain asset library. While characterizing the GSS process, we became aware of several interesting factors which affect the successful continued use of GSS. Many of these issues fall under the subject of evolving technologies, which were not available at the inception of GSS, but are now. Some of these technologies could be incorporated into the GSS process, thus making the whole asset library more usable. Other technologies are being considered as an alternative to the GSS process altogether. In this paper, we outline some of issues we will be considering in our continued study of GSS and the impact of evolving technologies.

Condon, S.↗

A Glass Can Be Half Full: Even in Microgravity

When conducting physical science research in space, the smallest vibration or disturbance can disrupt sensitive experiments. Back in the 1990s we developed an instrument, the Space Acceleration Measurement System (SAMS) that flew on the shuttle to monitor the vibration environment - but it wasn't very flexible. It could only measure vibrations for three users and only at fixed frequency ranges, and it had to be disassembled after each two-week mission to be readied for reuse. Then the International Space Station came along. Our researchers needed a second-generation system, the SAMS-II, which would measure acceleration and vibrations for multiple payloads conducting experiments throughout the life of the station. Measurement requirements were all over the map with a variety of frequencies that needed measuring over a broad dynamic range, so it was essential to develop a robust system that would be flexible enough to accommodate all the particular users. We came up with a concept using the Space Station's Ethernet as the means to talk between multiple remote triaxial sensor systems and a remote controller box. Ultimately, our job was to acquire data within the existing constraints of the station and to quickly and effectively get that information to the scientists. In 1994 we had a $2.1-million budget and a four-year development schedule aimed at achieving these goals. Technical risks were few and primarily resulted from uncertainty of ISS capabilities. At that point, we didn't worry about a thing programmatically; our cup runneth over.

Sutliff, Thomas↗

Rapid Spacecraft Payload Development: In-Orbit Demonstration of Flight Software Reuse, Scalability, and Dependability

As space mission design trends towards shared, multi-mission platforms and high-performance onboard computing architectures, the number of spacecraft launched into operation is also steadily rising. Through ridesharing, spacecraft miniaturization, and other cost-reduction measures, the barriers to space are lowering, resulting in compounded growth in the amount of flight software being deployed. To meet the needs of both the growing quantity and evolving nature of spacecraft, flight software design must accordingly adapt to support more efficient development, solutions to computational resource-sharing, and software reusability. This paper focuses on a software payload demonstrating several core technologies that improve the state-of-the-art in these identified areas. Launched into low-earth orbit in January 2022, our software payload was conceived, designed, and delivered in a span of merely two months. It was developed on top of the NASA core Flight System (cFS) framework and the Distributed Spacecraft Autonomy (DSA) Comm cFS application, which translates cFS software bus messages across a Data Distribution Service (DDS) network. The flight software, packaged in Linux container images, was deployed as one of 18 flight applications managed through the Unibap SpaceCloud Framework. The applications were run on a Unibap iX5-102 radiation-tolerant payload computer, hosted on the D-Orbit SCV-004 spacecraft as part of an ESA-sponsored in-orbit technology test. Our payload, referred to as the DSA D-Orbit software, demonstrates the reusability of the DSA Comm app in a substantially different context and purpose as its original mission. Comm’s original design goal was to reliably distribute messages between spacecraft swarms of arbitrary size and dynamic network topology. However, we leverage this same functionality to introduce redundancy and opportunistic parallel data processing in the context of a representative onboard image processing workload. This adaptive mission architecture was enabled in part by the SpaceCloud Framework’s use of container virtualization as the payload integration interface. By using a base container image with common high-level language runtimes and libraries, we were able to rapidly design, develop, and validate our image processing application without many of the technological barriers common to flight software development. We present details the goals, approach, results, and lessons learned through this technology demonstration experiment and contextualize those observations against present and future challenges in spacecraft software development.

computer programming↗

Fabrication and Testing of Mo-Re Heat Pipes Embedded in Carbon/Carbon

Refractory-composite/heat-pipe-cooled wing an tail leading edges are being considered for use on hypersonic vehicles to limit maximum temperatures to values below material reuse limits and to eliminate the need to actively cool the leading edges. The development of a refractory-composite/heat-pipe-cooled leading edge has evolved from the design stage to the fabrication and testing of heat pipes embedded in carbon/carbon (C/C). A three-foot-long, molybdenum-rhenium heat pipe with a lithium working fluid was fabricated and tested at an operating temperature of 2460 F to verify the individual heat-pipe design. Following the fabrication of this heat pipe, three additional heat pipes were fabricated and embedded in C/C. The C/C heat-pipe test article was successfully tested using quartz lamps in a vacuum chamber in both a horizontal and vertical orientation. Start up and steady state data are presented for the C/C heat-pipe test article. Radiography and eddy current evaluations were performed on the test article.

Glass, David E.↗