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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS1997

The GSFC Combined Approach of ODC Stockpiling and Tribological Testing to Mitigate the Risks of ODC Elimination

In response to the elimination of production of several Ozone Depleting Chemicals (ODC's) which have been widely used in successful space flight mechanism cleaning and lubricating procedures, GSFC developed and implemented an overall philosophy of mitigating the risks to flight hardware during the transition phase to ODC-free cleaning procedures. The short term leg of the philosophy was the stockpiling of an appropriate amount of ODC solvents such that all short term GSFC missions will be able to stay with or revert to heritage cleaning and lubricating procedures in the face of life issues. The long-term leg of that philosophy was the initiation of a several tier testing program that will deliver increasing amounts of information over the next few years, starting with accelerated lubricant life tests that compare lubricant life on surfaces cleaned with ODC solvents with lubricant life on surfaces cleaned with ODC-free solvents. While tribological testing, mechanism life testing and space-flight experience will ultimately bring us into the 21st century with environmentally friendly means of cleaning long-life precision mechanism components, many satellites will be launched over the next few years before a number of important tribological questions can be answered. In order to prepare for this challenge, the Materials Engineering Branch in cooperation with the Electromechanical Branch launched an intensive review of all ongoing missions. The failure risk was determined for each long-life lubricated mechanism based on a number of parameters, including 4 comparison of flight solvents used to clean the heritage/life test hardware. Also studied was the ability of the mechanism manufacturers to stockpile ODC's based on state laws and company policies. A stockpiling strategy was constructed based on this information and subsequently implemented. This paper provides an overview of the GSFC ODC elimination risk mitigation philosophy as well as a detailed examination of the development of the ODC stockpiling plan.

Predmore, Roamer↗
NASA NTRS1997

The GSFC Combined Approach of ODC Stockpiling and Tribological Testing to Mitigate the Risks of ODC Elimination

In response to the elimination of production of several Ozone Depleting Chemicals (ODCs) which have been widely used in successful space flight mechanism cleaning and lubricating procedures, GSFC developed and implemented an overall philosophy of mitigating the risks to flight hardware during the transition phase to ODC-Free cleaning procedures. One leg of that philosophy is the initiation of a several tier testing program which will deliver increasing amounts of information over the next few years, starting with original surface analysis comparisons between ODC and various ODC-Free cleaning technologies. The other leg is the stockpiling of an appropriate amount of ODC solvents such that all short term GSFC missions will be able to stay with or revert to heritage cleaning and lubricating procedures in the face of life issues. While tribological testing, mechanism life testing and space-flight experience will ultimately bring us into the 21st century with environmentally friendly means of cleaning long-life precision mechanism components, many satellites will be launched over the next few years with a number of important tribological questions unanswered. In order to prepare for this challenge, the Materials Engineering Branch in cooperation with the Electromechanical Branch launched an intensive review of all ongoing missions. The failure risk was determined for each long-life mechanism based on a number of parameters, including a comparison of flight solvents used to clean the heritage/life test hardware. Also studied was the ability of the mechanism manufacturers to stockpile ODCs based on state laws and company policies. A stockpiling strategy was constructed based on this information and subsequently implemented. This paper provides an overview of the GSFC ODC elimination risk mitigation philosophy as well as a detailed examination of the development of the ODC stockpiling plan.

Predmore, Roamer↗
NASA NTRS2000

Demonstration of Plasma Arc Environmental Technology Applications for the Demilitrization of DOD Stockpiles

Since 1989 the US Army Construction Engineering Research Laboratories (USACERL) have been active participants in the research and development towards establishing Plasma Arc Technology (PAT) as an efficient, economical, and safe hazardous waste immobilization tool. A plasma torch capable of generating high temperatures makes this technology a viable and powerful tool for the thermal destruction of various military industrial waste streams into an innocuous ceramic material no longer requiring hazardous waste landfill disposal. The emerging plasma environmental thermal treatment process has been used to safely and efficiently meet the waste disposal needs for various demilitarized components disposal needs, such as: (1) pyrotechnic smoke assemblies, (2) thermal batteries, (3) proximity fuses, (4) cartridge actuated devices (CADs), and (5) propellant actuated devices (PADs). MSE Technology Applications, Inc., (MSE) has proposed and fabricated a Mobile Plasma Treatment System to be a technology demonstrator for pilotscale mobile plasma waste processing. The system is capable of providing small-scale waste remediation services, and conducting waste stream applicability demonstrations. The Mobile Plasma Treatment System's innovative concept provides the flexibility to treat waste streams at numerous sites and sites with only a limited quantity of waste, yet too hazardous to transport to a regional fixed facility. The system was designed to be operated as skid mounted modules; consisting of a furnace module, controls module, offgas module, and ancillary systems module. All system components have been integrated to be operated from a single control station with both semi-continuous feeding and batch slag-pouring capability.

Smith, Ed↗
NASA NTRS2000

Demonstration of Plasma Arc Environmental Technology Applications for the Demilitarization of DOD Stockpiles

Since 1989 the U.S. Army Construction Engineering Research Laboratories (USACERL) have been active participants in the research and development toward establishing Plasma Arc Technology (PAT) as an efficient, economical, and safe hazardous waste immobilization tool. A plasma torch capable of generating high temperatures makes this technology a viable and powerful tool for the thermal destruction of various military industrial waste streams into an innocuous ceramic material no longer requiring hazardous waste landfill (Class 1) disposal. The emerging pl asma environmental thermal treatment process, has been used to safely and efficiently meet the waste disposal needs for various demilitarized components disposal needs, such as: pyrotechnic smoke assemblies, thermal batteries, proximity fuses, cartridge actuated devices (CAD's), and propellant actuated devices (PAD's). MSE Technology Applications, Inc., (MSE) has proposed and fabricated a Mobile Plasma Treatment System to be a technology demonstrator for pilot-scale mobile plasma waste processing. The system is capable of providing small-scale waste remediation services, and conducting waste stream applicability demonstrations. The Mobile Plasma Treatment System's innovative concept provides the flexibility to treat waste streams at numerous sites and sites with only a limited quantity of waste, yet too hazardous to transport to a regional fixed facility. The system was designed to be operated as skid mounted modules; consisting of a furnace module, controls module, offgas module, and ancillary systems module. All system components have been integrated to be operated from a single control station with both semi-continuous feeding and batch slag-pouring capability.

Smith, Ed↗
NASA NTRS1997

Dryden Flight Research Center Chemical Pharmacy Program

The Dryden Flight Research Center (DFRC) Chemical Pharmacy "Crib" is a chemical sharing system which loans chemicals to users, rather than issuing them or having each individual organization or group purchasing the chemicals. This cooperative system of sharing chemicals eliminates multiple ownership of the same chemicals and also eliminates stockpiles. Chemical management duties are eliminated for each of the participating organizations. The chemical storage issues, hazards and responsibilities are eliminated. The system also ensures safe storage of chemicals and proper disposal practices. The purpose of this program is to reduce the total releases and transfers of toxic chemicals. The initial cost of the program to DFRC was $585,000. A savings of $69,000 per year has been estimated for the Center. This savings includes the reduced costs in purchasing, disposal and chemical inventory/storage responsibilities. DFRC has chemicals stored in 47 buildings and at 289 locations. When the program is fully implemented throughout the Center, there will be three chemical locations at this facility. The benefits of this program are the elimination of chemical management duties; elimination of the hazard associated with chemical storage; elimination of stockpiles; assurance of safe storage; assurance of proper disposal practices; assurance of a safer workplace; and more accurate emissions reports.

Davis, Bette↗
NASA NTRS1970

Experimental applications of multispectral data to natural resource inventory and survey

The feasibility of using multispectral, color, color infrared, thermal infrared imagery and related ground data to recognize, identify, determine and monitor the status of mineral ore and metals stockpiles is studied. An attempt was made to identify valid, unique spectral signatures of such materials for possible use under a wide variety of environmental circumstances. Research emphasis was upon the analysis of the multiband imagery from the various film-filter combinations, using density analysis techniques.

Mallon, H. J.↗
NASA NTRS1979

Computation of spare parts requirements

Statistical analysis determines probability of failure for N-1 spares. Analysis can help reduce downtime in industrial processes by determining number of spare parts that must be stockpiled. Analysis can also be inverted to decide if number of spares on hand is sufficient for lifetime needs of system.

Mezzacappa, M. A.↗
NASA NTRS1977

Dynamic spares provisioning for the DSN

A method is proposed to maintain cost-effective spares stockpiles for an entire DSN station or complex as new modules or subsystems are continuously added. Levels of spares are calculated individually for each new module type so as to conform to an established standard for the entire spares pool. Finding the spares levels is computationally simplified and in many cases is reduced to consulting a Down-Time Ratio Chart. A simple modification permits taking into account a criticality factor.

Eisenberger, I.↗
NASA NTRS1978

Contingency plans for chromium utilization. Publication NMAB-335

The United States depends entirely on foreign sources for the critical material, chromium, making it very vulnerable to supply disruptions. The effectiveness of programs such as stockpiling, conservation, and research and development for substitutes to reduce the impact of disruption of imports of chromite and ferrochromium are discussed. Alternatives for decreasing chromium consumption also are identified for chromium-containing materials in the areas of design, processing, and substitution.

Source record↗
NASA NTRS1987

Evaluation of cryogenic system test options for the OTV on-orbit propellant depot

Future space missions to geosynchronous, lunar, and planetary orbits will require an orbital depot for stockpiling propellants. This depot will provide long-term storage of cryogens, requiring new technologies for fluid management in microgravity and further development of thermal management technologies for minimization of cryogen boiloff. Preliminary evaluations have been made to define a test program approach for reducing technical risk through verifying performance models and building a base of engineering data for depot design. A number of testing options were defined and evaluated, leading to selection of ground testing combined with an orbital systems test. Ground testing is inadequate because of critical microgravity concerns; extending testing aboard the Space Station was eliminated because the data would not be available soon enough to benefit the propellant depot design. The orbital test would either be a short-term test carried out in the cargo bay of the Space Shuttle Orbiter using a nonhazardous cryogen or a longer term test carried out with hydrogen aboard a free-flying experiment orbited with an expendable launch vehicle.

Schuster, John R.↗
NASA NTRS1988

Helium-3 blankets for tritium breeding in fusion reactors

It is concluded that He-3 blankets offers considerable promise for tritium breeding in fusion reactors: good breeding potential, low operational risk, and attractive safety features. The availability of He-3 resources is the key issue for this concept. There is sufficient He-3 from decay of military stockpiles to meet the International Thermonuclear Experimental Reactor needs. Extraterrestrial sources of He-3 would be required for a fusion power economy.

Steiner, Don↗
NASA NTRS1989

A review of the supply of liquid propellants and other fluids in support of the Space Shuttle Program

In this study, over twenty significant liquid propellants and other fluids were reviewed as to their supply in support of the Space Shuttle Program (SSP), primarily at KSC. The uniqueness of most of the products, either by their application or production characteristics, present a variety of supply issues to contend with. Each, however, is critical to the success of the SSP. It becomes necessary to formulate, and maintain, a logistic approach to assure a continued availability of each product. For convenience, two categories were established. One, labeled limited-availability, represents those products wherein they are single sourced, have production restrictions and/or there has been a history of supply problems. The other, labeled universally-available, is characteristic of those having several sources and/or having little, if any, historical supply problems. This last category was not examined in depth. Through concepts of establishing stockpile inventories, multiple supply contracts, or other arrangements, the supply of liquid propellants and other fluids can be assured.

Churchwell, Stacy E.↗
NASA NTRS1989

The resources of Mars for human settlement

Spacecraft exploration of Marshas shown that the essential resources necessary for life support are present on the Martian surface. The key life-support compounds O2, N2, and H2O are available on Mars. The soil could be used as radiation shielding and could provide many useful industrial and construction materials. Compounds with high chemical energy, such as rocket fuels, can be manufactured in-situ on Mars. Solar power, and possibly wind power, are available and practical on Mars. Preliminary engineering studies indicate that fairly autonomous processes can be designed to extract and stockpile Martian consumables.

Meyer, Thomas R.↗
NASA NTRS1995

Solar flares controlled by helicity conservation

The energy release in a class of solar flares is studied on the assumption that during burst events in highly conducting plasma the magnetic helicity of plasma is approximately conserved. The available energy release under a solar flare controlled by the helicity conservation is shown to be defined by the magnetic structure of the associated prominence. The approach throws light on some solar flare enigmas: the role of the associated prominence. The approach throws light on some solar flare enigmas: the role of the associated prominences; the discontinuation of the reconnection of magnetic lines long before the complete reconnection of participated fields occurs; the existence of quiet prominences which, in spite of their usual optical appearance, do not initiate any flare events; the small energy release under a solar flare in comparison with the stockpile of magnetic energy in surrounding fields. The predicted scale of the energy release is in a fair agreement with observations.

Gliner, Erast B.↗
NASA NTRS2000

NARC Rayon Replacement Program for the Space Shuttle Reusable Solid Rocket Motor Nozzle: Screening Summary

Thiokol Corporation and NASA MSFC are jointly developing a replacement for North American Rayon Corporation (NARC) Aerospace Grade Rayon (1650/720 continuous filament), the precursor for the Carbon Cloth Phenolic (CCP) ablatives used in the Space Shuttle Reusable Solid Rocket Motor (RSRM) Nozzles. NARC discontinued production of Aerospace Grade Rayon in September 1997. NASA maintains a stockpile of NARC Rayon to support RSRM production through the summer of 2005. The program plan for selection and qualification of a replacement for NARC rayon was approved in August 1998. Screening activities began in February 1999. The intent of this paper is to provide a summary of the data generated during the screening phase of the NARC Rayon Replacement Program. Twelve cellulose based fibers (rayon and lyocell) were evaluated. These fibers were supplied by three independent vendors. Many of these fibers were carbonized by two independent carbonizers. Each candidate was tested according to standard acceptance test methods at each step of the manufacturing process. Additional testing was performed with the candidate CCPS, including hot fire tests, Process studies and mechanical and thermal characterization. Six of the twelve fiber candidates tested were dropped at the conclusion of Phase 1. The reasons for the elimination of these candidates included; difficulties in processing the material in the whitegoods, carbon and CCP forms; poor composite mechanical performance; and future availability concerns. The remaining six fibers demonstrated enough promise to merit continued evaluation and optimization of the CCP fabrication process. Note: Certain CCP data falls under the restrictions of US export laws, (ITAR, etc.) and will not be included in this paper.

Cook, R. V.↗
NASA NTRS2002

NARC Rayon Replacement Program

This viewgraph presentation provides information on the search for a replacement product for the aerospace grade rayon formerly used in the reusable solid rocket motor (RSRM). The rayon used in RSRMs is no longer produced by the North American Rayon Corporation (NARC), though NASA has stockpiled rayon to be used until a suitable replacement is found to be used in the RSRM nozzle carbon cloth phenolic (CCP). The primary considerations are performance, process ability, variability, long term availability, and cost. The preference will be given to commercial off-the-shelf products as opposed to those which are custom made. The candidate materials have been tested in previous phases of this selection process, and Enka Textile Rayon has emerged as a possible fabric, though its availability is still in question.

Wilson, Kenneth P.↗
NASA NTRS1978

Waterway Ice Thickness Measurements

The ship on the opposite page is a U. S. Steel Corporation tanker cruising through the ice-covered waters of the Great Lakes in the dead of winter. The ship's crew is able to navigate safely by plotting courses through open water or thin ice, a technique made possible by a multi-agency technology demonstration program in which NASA is a leading participant. Traditionally, the Great Lakes-St. Lawrence Seaway System is closed to shipping for more than three months of winter season because of ice blockage, particularly fluctuations in the thickness and location of ice cover due to storms, wind, currents and variable temperatures. Shippers have long sought a system of navigation that would allow year-round operation on the Lakes and produce enormous economic and fuel conservation benefits. Interrupted operations require that industrial firms stockpile materials to carry them through the impassable months, which is costly. Alternatively, they must haul cargos by more expensive overland transportation. Studies estimate the economic benefits of year-round Great Lakes shipping in the hundreds of millions of dollars annually and fuel consumption savings in the tens of millions of gallons. Under Project Icewarn, NASA, the U.S. Coast Guard and the National Oceanic Atmospheric Administration collaborated in development and demonstration of a system that permits safe year-round operations. It employs airborne radars, satellite communications relay and facsimile transmission to provide shippers and ships' masters up-to-date ice charts. Lewis Research Center contributed an accurate methods of measuring ice thickness by means of a special "short-pulse" type of radar. In a three-year demonstration program, Coast Guard aircraft equipped with Side-Looking Airborne Radar (SLAR) flew over the Great Lakes three or four times a week. The SLAR, which can penetrate clouds, provided large area readings of the type and distribution of ice cover. The information was supplemented by short-pulse radar measurements of ice thickness. The radar data was relayed by a NOAA satellite to a ground station where NOAA analyzed it and created picture maps, such as the one shown at lower left, showing where icebreakers can cut paths easily or where shipping can move through thin ice without the aid of icebreakers. The ice charts were then relayed directly to the wheelhouses of ships operating on the Lakes. Following up the success of the Great Lakes program, the icewarn team applied its system in another demonstration, this one a similarly successful application designed to aid Arctic coast shipping along the Alaskan North Slope. Further improvement of the ice-monitoring system is planned. Although aircraft-mounted radar is effective, satellites could provide more frequent data. After the launch this year of Seasat, an ocean-monitoring satellite, NASA will conduct tests to determine the ice-mapping capability and accuracy of satellite radar images.

Source record↗
NASA NTRS2008

Computer Model Locates Environmental Hazards

Catherine Huybrechts Burton founded San Francisco-based Endpoint Environmental (2E) LLC in 2005 while she was a student intern and project manager at Ames Research Center with NASA's DEVELOP program. The 2E team created the Tire Identification from Reflectance model, which algorithmically processes satellite images using turnkey technology to retain only the darkest parts of an image. This model allows 2E to locate piles of rubber tires, which often are stockpiled illegally and cause hazardous environmental conditions and fires.

Source record↗