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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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NASA NTRS1996

Neuroendocrine and Immune System Responses with Spaceflights

Despite the fact that the first human was in space during 1961 and individuals have existed in a microgravity environment for more than a year, there are limited spaceflight data available on the responses of the neuroendocrine and immune systems. Because of mutual interactions between these respective integrative systems, it is inappropriate to assume that the responses of one have no impact on functions of the other. Blood and plasma volume consistently decrease with spaceflight; hence, blood endocrine and immune constituents will be modified by both gravitational and measurement influences. The majority of the in-flight data relates to endocrine responses that influence fluids and electrolytes during the first month in space. Adrenocorticotropin (ACTH), aldo-sterone. and anti-diuretic hormone (ADH) appear to be elevated with little change in the atrial natriuretic peptides (ANP). Flight results longer than 60 d show increased ADH variability with elevations in angiotensin and cortisol. Although post-flight results are influenced by reentry and recovery events, ACTH and ADH appear to be consistently elevated with variable results being reported for the other hormones. Limited in-flight data on insulin and growth hormone levels suggest they are not elevated to counteract the loss in muscle mass. Post-flight results from short- and long-term flights indicate that thyroxine and insulin are increased while growth hormone exhibits minimal change. In-flight parathyroid hormone (PTH) levels are variable for several weeks after which they remain elevated. Post-flight PTH was increased on missions that lasted either 7 or 237 d, whereas calcitonin concentrations were increased after 1 wk but decreased after longer flights. Leukocytes are elevated in flights of various durations because of an increase in neutrophils. The majority of post-flight data indicates immunoglobulin concentrations are not significantly changed from pre-flight measurements. However, the numbers of T-lymphocytes and natural killer cells are decreased with post-flight conditions. Of the lymphokines, interleukin-2 production, lymphocyte responsiveness, and the activity of natural killer cells are consistently reduced post-flight. Limited head-down tilt (HDT) data suggest it is an effective simulation model for microgravity investigations. Neuroendocrine and pharmacological countermeasures are virtually nonexistent arid should become high priority items for future research. Although exercise has the potential to be an effective countermeasure for various neuroen-docrine-immune responses in microgravity, this concept must be tested before flights to Mars are scheduled.

Tipton, Charles M.↗
NASA NTRS2000

Operational Implementation of a 2-Hour Prebreathe Protocol for International Space Station

Procedures, equipment, and analytical techniques were developed to implement the ground tested 2-hour protocol in-flight operations. The methods are: 1) The flight protocol incorporates additional safety margin over the ground tested protocol. This includes up to 20 min of additional time on enriched O2 during suit purge and pressure check, increased duration of extravehicular activity (EVA) preparation exercise during O2 prebreathing (up to 90 min vs; the tested 24 min), and reduced rates of depressurization. The ground test observations were combined with model projections of the conservative measures (using statistical models from Duke University and NASA JSQ to bound the risk of Type I and Type II decompression sickness (DCS). 2) An inflight exercise device using the in-flight ergometer and elastic tubes for upper body exercise was developed to replicate the dual cycle exercise in the ground trials. 3) A new in-flight breathing system was developed and man-tested. 4) A process to monitor inflight experience with the protocol, including the use of an in-suit Doppler bubble monitor when available, was developed. The results are: 1) The model projections of the conservative factors of the operational protocol were shown to reduce the risk of DCS to levels consistent with the observations of no DCS to date in the shuttle program. 2) Cross over trials of the dual cycle ergometer used in ground tests and the in-flight exercise system verified that02consumption and the % division of work between upper and lower body was not significantly different at the p= 0.05 level. 3) The in-flight breathing system was demonstrated to support work rates generating 75% O2(max) in 95 percentile subjects. 4) An in-flight monitoring plan with acceptance criteria was put in place for the 2-hour prebreathe protocol. And the conclusions are: The 2-hour protocol has been approved for flight, and all implementation efforts are in place to allow use of the protocol as early as flight ISS 7A, now scheduled in November of 2000.

Waligora, James M.↗
NASA NTRS1999

Constrained Vapor Bubble

The nonisothermal Constrained Vapor Bubble, CVB, is being studied to enhance the understanding of passive systems controlled by interfacial phenomena. The study is multifaceted: 1) it is a basic scientific study in interfacial phenomena, fluid physics and thermodynamics; 2) it is a basic study in thermal transport; and 3) it is a study of a heat exchanger. The research is synergistic in that CVB research requires a microgravity environment and the space program needs thermal control systems like the CVB. Ground based studies are being done as a precursor to flight experiment. The results demonstrate that experimental techniques for the direct measurement of the fundamental operating parameters (temperature, pressure, and interfacial curvature fields) have been developed. Fluid flow and change-of-phase heat transfer are a function of the temperature field and the vapor bubble shape, which can be measured using an Image Analyzing Interferometer. The CVB for a microgravity environment, has various thin film regions that are of both basic and applied interest. Generically, a CVB is formed by underfilling an evacuated enclosure with a liquid. Classification depends on shape and Bond number. The specific CVB discussed herein was formed in a fused silica cell with inside dimensions of 3x3x40 mm and, therefore, can be viewed as a large version of a micro heat pipe. Since the dimensions are relatively large for a passive system, most of the liquid flow occurs under a small capillary pressure difference. Therefore, we can classify the discussed system as a low capillary pressure system. The studies discussed herein were done in a 1-g environment (Bond Number = 3.6) to obtain experience to design a microgravity experiment for a future NASA flight where low capillary pressure systems should prove more useful. The flight experiment is tentatively scheduled for the year 2000. The SCR was passed on September 16, 1997. The RDR is tentatively scheduled for October, 1998.

Huang, J.↗
NASA NTRS2000

AWE: Aviation Weather Data Visualization Environment

Weather is one of the major causes of aviation accidents. General aviation (GA) flights account for 92% of all the aviation accidents, In spite of all the official and unofficial sources of weather visualization tools available to pilots, there is an urgent need for visualizing several weather related data tailored for general aviation pilots. Our system, Aviation Weather Data Visualization Environment AWE), presents graphical displays of meteorological observations, terminal area forecasts, and winds aloft forecasts onto a cartographic grid specific to the pilot's area of interest. Decisions regarding the graphical display and design are made based on careful consideration of user needs. Integral visual display of these elements of weather reports is designed for the use of GA pilots as a weather briefing and route selection tool. AWE provides linking of the weather information to the flight's path and schedule. The pilot can interact with the system to obtain aviation-specific weather for the entire area or for his specific route to explore what-if scenarios and make "go/no-go" decisions. The system, as evaluated by some pilots at NASA Ames Research Center, was found to be useful.

Spirkovska, Lilly↗
NASA NTRS2006

Mechanism Development, Testing, and Lessons Learned for the Advanced Resistive Exercise Device

The Advanced Resistive Exercise Device (ARED) has been developed at NASA Johnson Space Center, for the International Space Station (ISS) program. ARED is a multi-exercise, high-load resistive exercise device, designed for long duration, human space missions. ARED will enable astronauts to effectively maintain their muscle strength and bone mass in the micro-gravity environment more effectively than any other existing devices. ARED's resistance is provided via two, 20.3 cm (8 in) diameter vacuum cylinders, which provide a nearly constant resistance source. ARED also has a means to simulate the inertia that is felt during a 1-G exercise routine via the flywheel subassembly, which is directly tied to the motion of the ARED cylinders. ARED is scheduled to fly on flight ULF 2 to the ISS and will be located in Node 1. Presently, ARED is in the middle of its qualification and acceptance test program. An extensive testing program and engineering evaluation has increased the reliability of ARED by bringing potential design issues to light before flight production. Some of those design issues, resolutions, and design details will be discussed in this paper.

Lamoreaux, Christopher D.↗
NASA NTRS2006

NASA's J-2X Engine Builds on the Apollo Program for Lunar Return Missions

In January 2006, NASA streamlined its U.S. Vision for Space Exploration hardware development approach for replacing the Space Shuttle after it is retired in 2010. The revised CLV upper stage will use the J-2X engine, a derivative of NASA s Apollo Program Saturn V s S-II and S-IVB main propulsion, which will also serve as the Earth Departure Stage (EDS) engine. This paper gives details of how the J- 2X engine effort mitigates risk by building on the Apollo Program and other lessons learned to deliver a human-rated engine that is on an aggressive development schedule, with first demonstration flight in 2010 and human test flights in 2012. It is well documented that propulsion is historically a high-risk area. NASA s risk reduction strategy for the J-2X engine design, development, test, and evaluation is to build upon heritage hardware and apply valuable experience gained from past development efforts. In addition, NASA and its industry partner, Rocketdyne, which originally built the J-2, have tapped into their extensive databases and are applying lessons conveyed firsthand by Apollo-era veterans of America s first round of Moon missions in the 1960s and 1970s. NASA s development approach for the J-2X engine includes early requirements definition and management; designing-in lessons learned from the 5-2 heritage programs; initiating long-lead procurement items before Preliminary Desi& Review; incorporating design features for anticipated EDS requirements; identifying facilities for sea-level and altitude testing; and starting ground support equipment and logistics planning at an early stage. Other risk reduction strategies include utilizing a proven gas generator cycle with recent development experience; utilizing existing turbomachinery ; applying current and recent main combustion chamber (Integrated Powerhead Demonstrator) and channel wall nozzle (COBRA) advances; and performing rigorous development, qualification, and certification testing of the engine system, with a philosophy of "test what you fly, and fly what you test". These and other active risk management strategies are in place to deliver the J-2X engine for LEO and lunar return missions as outlined in the U.S. Vision for Space Exploration.

Snoddy, Jimmy R.↗
NASA NTRS2012

Automation of Hubble Space Telescope Mission Operations

On June 13, 2011, after more than 21 years, 115 thousand orbits, and nearly 1 million exposures taken, the operation of the Hubble Space Telescope successfully transitioned from 24x7x365 staffing to 815 staffing. This required the automation of routine mission operations including telemetry and forward link acquisition, data dumping and solid-state recorder management, stored command loading, and health and safety monitoring of both the observatory and the HST Ground System. These changes were driven by budget reductions, and required ground system and onboard spacecraft enhancements across the entire operations spectrum, from planning and scheduling systems to payload flight software. Changes in personnel and staffing were required in order to adapt to the new roles and responsibilities required in the new automated operations era. This paper will provide a high level overview of the obstacles to automating nominal HST mission operations, both technical and cultural, and how those obstacles were overcome.

Burley, Richard↗
NASA NTRS2012

Projected Demand and Potential Impacts to the National Airspace System of Autonomous, Electric, On-Demand Small Aircraft

Electric propulsion and autonomy are technology frontiers that offer tremendous potential to achieve low operating costs for small-aircraft. Such technologies enable simple and safe to operate vehicles that could dramatically improve regional transportation accessibility and speed through point-to-point operations. This analysis develops an understanding of the potential traffic volume and National Airspace System (NAS) capacity for small on-demand aircraft operations. Future demand projections use the Transportation Systems Analysis Model (TSAM), a tool suite developed by NASA and the Transportation Laboratory of Virginia Polytechnic Institute. Demand projections from TSAM contain the mode of travel, number of trips and geographic distribution of trips. For this study, the mode of travel can be commercial aircraft, automobile and on-demand aircraft. NASA's Airspace Concept Evaluation System (ACES) is used to assess NAS impact. This simulation takes a schedule that includes all flights: commercial passenger and cargo; conventional General Aviation and on-demand small aircraft, and operates them in the simulated NAS. The results of this analysis projects very large trip numbers for an on-demand air transportation system competitive with automobiles in cost per passenger mile. The significance is this type of air transportation can enhance mobility for communities that currently lack access to commercial air transportation. Another significant finding is that the large numbers of operations can have an impact on the current NAS infrastructure used by commercial airlines and cargo operators, even if on-demand traffic does not use the 28 airports in the Continental U.S. designated as large hubs by the FAA. Some smaller airports will experience greater demand than their current capacity allows and will require upgrading. In addition, in future years as demand grows and vehicle performance improves other non-conventional facilities such as short runways incorporated into shopping mall or transportation hub parking areas could provide additional capacity and convenience.

Smith, Jeremy C.↗
NASA NTRS2014

Large-Scale Spacecraft Fire Safety Tests

An international collaborative program is underway to address open issues in spacecraft fire safety. Because of limited access to long-term low-gravity conditions and the small volume generally allotted for these experiments, there have been relatively few experiments that directly study spacecraft fire safety under low-gravity conditions. Furthermore, none of these experiments have studied sample sizes and environment conditions typical of those expected in a spacecraft fire. The major constraint has been the size of the sample, with prior experiments limited to samples of the order of 10 cm in length and width or smaller. This lack of experimental data forces spacecraft designers to base their designs and safety precautions on 1-g understanding of flame spread, fire detection, and suppression. However, low-gravity combustion research has demonstrated substantial differences in flame behavior in low-gravity. This, combined with the differences caused by the confined spacecraft environment, necessitates practical scale spacecraft fire safety research to mitigate risks for future space missions. To address this issue, a large-scale spacecraft fire experiment is under development by NASA and an international team of investigators. This poster presents the objectives, status, and concept of this collaborative international project (Saffire). The project plan is to conduct fire safety experiments on three sequential flights of an unmanned ISS re-supply spacecraft (the Orbital Cygnus vehicle) after they have completed their delivery of cargo to the ISS and have begun their return journeys to earth. On two flights (Saffire-1 and Saffire-3), the experiment will consist of a flame spread test involving a meter-scale sample ignited in the pressurized volume of the spacecraft and allowed to burn to completion while measurements are made. On one of the flights (Saffire-2), 9 smaller (5 x 30 cm) samples will be tested to evaluate NASAs material flammability screening tests. The first flight (Saffire-1) is scheduled for July 2015 with the other two following at six-month intervals. A computer modeling effort will complement the experimental effort. Although the experiment will need to meet rigorous safety requirements to ensure the carrier vehicle does not sustain damage, the absence of a crew removes the need for strict containment of combustion products. This will facilitate the first examination of fire behavior on a scale that is relevant to spacecraft fire safety and will provide unique data for fire model validation.

Combustion↗
NASA NTRS2015

Scanning L-Band Active Passive (SLAP) - Recent Results from an Airborne Simulator for SMAP

Scanning L-band Active Passive (SLAP) is a recently-developed NASA airborne instrument specially tailored to simulate the new Soil Moisture Active Passive (SMAP) satellite instrument suite. SLAP conducted its first test flights in December, 2013 and participated in its first science campaign-the IPHEX ground validation campaign of the GPM mission-in May, 2014. This paper will present results from additional test flights and science observations scheduled for 2015.

instruments↗
NASA NTRS2015

Flight Software for the LADEE Mission

The Lunar Atmosphere and Dust Environment Explorer (LADEE) spacecraft was launched on September 6, 2013, and completed its mission on April 17, 2014 with a directed impact to the Lunar Surface. Its primary goals were to examine the lunar atmosphere, measure lunar dust, and to demonstrate high rate laser communications. The LADEE mission was a resounding success, achieving all mission objectives, much of which can be attributed to careful planning and preparation. This paper discusses some of the highlights from the mission, and then discusses the techniques used for developing the onboard Flight Software. A large emphasis for the Flight Software was to develop it within tight schedule and cost constraints. To accomplish this, the Flight Software team leveraged heritage software, used model based development techniques, and utilized an automated test infrastructure. This resulted in the software being delivered on time and within budget. The resulting software was able to meet all system requirements, and had very problems in flight.

LADEE↗
NASA NTRS2017

Cryogenic Fluid Management Technology Development Roadmaps

Advancement in Cryogenic Fluid Management (CFM) Technologies is essential for achieving NASA's future long duration missions. Propulsion systems utilizing cryogens are necessary to achieve mission success. Current State Of the Art (SOA) CFM technologies enable cryogenic propellants to be stored for several hours. However, some envisioned mission architectures require cryogens to be stored for two years or longer. The fundamental roles of CFM technologies are long term storage of cryogens, propellant tank pressure control and propellant delivery. In the presence of heat, the cryogens will "boil-off" over time resulting in excessive pressure buildup, off-nominal propellant conditions, and propellant loss. To achieve long term storage and tank pressure control, the CFM elements will intercept and/or remove any heat from the propulsion system. All functions are required to perform both with and without the presence of a gravitational field. Which CFM technologies are required is a function of the cryogens used, mission architecture, vehicle design and propellant tank size. To enable NASA's crewed mission to the Martian surface, a total of seventeen CFM technologies have been identified to support an In-Space Stage and a Lander/Ascent Vehicle. Recognizing that FY2020 includes a Decision Point regarding the In-Space Stage Architecture, a set of CFM Technology Development Roadmaps have been created identifying the current Technology Readiness Level (TRL) of each element, current technology "gaps", and existing technology development efforts. The roadmaps include a methodical approach and schedule to achieve a flight demonstration in FY2023, hence maturing CFM technologies to TRL 7 for infusion into the In-Space Stage Preliminary Design.

Stephens, J. R.↗
NASA NTRS2018

Testing and Development of NEA Scout Solar Sail Deployer Mechanism

The Near Earth Asteroid (NEA) [1] Scout is a deep space CubeSat designed to use an 86 m2 solar sail to navigate to a near earth asteroid called VG 1991. The solar sail deployment mechanism aboard NEA Scout has gone through numerous design cycles and ground tests since its conception in 2014. An engineering development unit (EDU) was constructed in the spring of 2016 and since then, the NEA Scout team has completed numerous ground deployments aiming to mature the deployment system and the ground test methods used to validate that system. Testing a large, non-rigid gossamer system in 1G environments has presented its difficulties to numerous solar sailing programs before, but NEA Scout's size, sail configuration, and budget has led the team to develop new deployment techniques and uncover new practices while improving their test methods. The program has planned and completed 5 separate full scale sail deployments to date, with a flight sail deployment test scheduled for FY18. The paper entitled "Design and Development of NEA Scout Solar Sail Deployer Mechanism" [2] was presented at the 43rd Aerospace Mechanisms Symposia. Since then, the system has matured and completed ascent vent, random vibration, boom deployment and sail deployment tests. This paper will discuss the lessons learned and advancements made while working on solar sail deployment testing and mechanical redesign cycles.

Few, Alex↗
NASA NTRS2018

NASA's Cryogenic Fluid Management Technology Development Roadmaps

The maturation of Cryogenic Fluid Management (CFM) Technologies is essential for achieving NASA's future long duration missions. Propulsion systems utilizing cryogens are necessary to achieve NASA's exploration missions to the moon, Mars, and beyond. Current State Of the Art (SOA) CFM technologies enable cryogenic propellants to be stored for several hours prior to their use. However, some envisioned mission architectures require that cryogens to be stored for two years or longer. The fundamental roles of CFM technologies are long term storage of cryogens, propellant tank pressure control and propellant delivery. In the presence of heat, the cryogens will "boil-off" over time resulting in excessive pressure buildup, off-nominal propellant conditions for engine consumption, and propellant loss. To achieve long term storage and tank pressure control, the CFM elements will intercept and/or remove any heat from the propulsion system. All functions are required to be performed both with and without the presence of a gravitational field. Which CFM technologies are required is a function of the cryogens used, mission architecture, vehicle design and propellant tank size. To enable NASA's crewed missions beyond Low Earth Orbit, a total of twenty-seven CFM technologies have been identified to support various In-Space Stages and Lander/Ascent Vehicles. A set of CFM Technology Development Roadmaps have been created identifying the current Technology Readiness Level (TRL) of each element, current technology "gaps", and existing technology development efforts. The roadmaps include a methodical approach and schedule to achieve a flight demonstration, hence maturing CFM technologies to TRL 6/7 for infusion into the NASA's exploration elements. Additionally, a survey of the aerospace industry was completed to understand their views on the various technologies and how they would be infused. This does not cover all possible technologies, but rather those that are of interest to NASA specifically.

Cryogenic fluid management↗
NASA NTRS2020

Changes in Frequency of the Severity and Type of Aviation Accidents (1987 to 2016)

This document reports the fourth analysis to identify the types of accidents with the greatest impact on the overall safety risk in U.S. civil aviation. The first three analyses examined accidents in 1997-20061, in 2001-20102 and in 2005-20143. The safety risks herein are defined to include four elements: (1) the number of total accidents; (2) the number of fatal accidents; (3) the number of total injuries; (4) the number of fatal injuries. Two of the previous analyses also included the number of incidents, but incident data since 2007 are difficult to separate by flight operation. Other incident details are no longer recorded as well. Due to these changes, the author’s working copy of the incident data has not been updated since 2011 (for incidents through 2010), and the incident data were not included in this analysis. Powerplant and non-powerplant system component failures were the only categories with a greater contribution to the overall safety risk from incidents than from accidents. Accident types, as well as accident rates, have been shown to vary considerably among different flight operations (e.g., large air carriers versus general aviation). For this reason, all analyses were done separately for four types of flight operations (Part 121, Scheduled Part 135, Non- Scheduled Part 135 and Part 91).

Evans, Joni K.↗
NASA NTRSDate not supplied

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) Solar Sounding Rocket Campaign – Calibration and Performance

The Marshall Grazing Incidence X-ray Spectrometer (MaGIXS) is a sounding rocket experiment that is designed to observe, for the first time, soft X-ray spectra of high-temperature, low-emission plasma of coronal structures spatially resolved along a narrow slit.MaGIXS observation involves a set of high temperature spectral lines in soft X-rays from 0.5 - 2.0 keV from an active region core,which will extend the DEM coverage from 3MK to 10MK constraining the slope of the DEM fall-off. The novel instrument designincludes a Wolter-I type telescope and a 3-optic grazing-incidence spectrometer. The spectrometer consists of a finite conjugatemirror pair and a blazed planar, varied line spaced grating, which disperses the rays on to a CCD and provides a high spatial andspectral resolution. Component level instrument testing, integration of the instrument and end-to-end X-ray calibration are carriedout using the X-ray and Cryogenic Facility (XRCF) at NASA Marshall Space Flight Center. MaGIXS is scheduled for launch in2021. We will present the results of X-ray calibration tests for MaGIXS and discuss the expected inflight performance throughdifferent solar observation scenarios.

P. S. Athiray↗
NASA NTRSDate not supplied

Enterprise Mission Integration for Artemis Lunar Missions

Mission integration is an iterative process by which a specific mission is formulated, refined, planned, and executed within the established vehicle(s), architecture, and ground systems design. Mission integration includes the people, vehicle(s) and ground hardware/software, products, processes, analyses, schedules, facilities, Certification of Flight Readiness, etc. The Artemis Mission Integration Task Team (MITT) developed a series of products and processes to support the complex mission integration across various Programs within the Artemis Mission Campaign (Orion, Space Launch Systems, Exploration Ground Systems, Gateway, Human Landing System, and Extravehicular Activity and Human Surface Mobility). The Moon to Mars (M2M) Program is referred to as ‘the enterprise’ as it includes both the M2M organization and the Programs supporting the Artemis Mission Campaign. Artemis Mission Integration has five phases: mission capability, mission definition, mission preparation, mission execution, and post-mission assessment. This paper focuses on one of the enterprise-level mission checkpoints as a kick-off to the Mission Preparation phase, the Mission Integration Review (MIR), which occurs 18-24 months prior to launch. The MIR helps to confirm the defined mission technical baseline is within the existing analyzed design envelope. Details are provided on the identification of dependencies, issues, or gaps for mission-specific objectives and requirements, as well as the definition of the analysis, training, mission execution products, facilities, and detailed supporting operations requirements. The MIR was held for both Artemis I and II and this paper aims to share with the aerospace community its value as we prepare for upcoming Artemis Missions.

Mary Anne Plaza↗