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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 757 records · Page 42
All sourcesNASA NTRSDOE OSTI
NASA NTRS1984

Cryogenic and thermal design for the Space Infrared Telescope Facility (SIRTF)

The 1-meter class cryogenically cooled Space Infrared Telescope Facility (SIRTF) planned by NASA, is scheduled for a 1992 launch. SIRTF would be deployed from the Shuttle, and placed into a sun synchronous polar orbit of 700 km. The facility has been defined for a mission with a minimum initial lifetime of one year in orbit with mission extension that could be made possible through in-orbit servicing of the superfluid helium cryogenic system, and use of a thermal control system. The superfluid dewar would use an orbital disconnect system for the tank supports, and vapor cooling of the barrel baffle. The transient analysis of the design shows that the superfluid helium tank with no active feedback comes within temperature requirements for the nominal orbital aperture heat load, quiescent instrument, and chopper conditions.

Lee, J. H.↗
NASA NTRS1987

Servicing operations for the SIRTF Observatory at the Space Station

This paper describes the servicing requirements, plans, and proposed Space Station-based servicing operations for the Space Infrared Telescope Facility (SIRTF) Observatory. SIRTF is a cryogenically-cooled, long-life, one meter class space telescope which will be operated by NASA as a free-flying observatory for infrared astronomy, in the mid-1990's. To achieve its 5-year lifetime requirement (10 year goal), SIRTF must be replenished periodically with cryogenic helium and have its life-limited modular subsystems replaced; capability for contingency repair of warm components will also be provided in the Observatory design. A general description of the SIRTF Observatory is given, including options for the support systems (spacecraft). The overall servicing philosophy and plans are addressed with scheduling and needed support elements described. A proposed Space Station-based servicing scenario is described, including orbital transfer, servicing and checkout operations. A detailed description and timeline for liquid helium replenishment operations is provided, including a conceptual design and technology development program for the cryogenic helium transfer dewar (tanker). Finally, a preliminary SIRTF spares/logistics philosophy is outlined, including tradeoffs to be considered.

Wiltsee, Christopher B.↗
NASA NTRS1989

GetAway Tether Experiment (GATE) for the Tether Dynamics Explorer (TDE) series

Designs for the GetAway Tether Experiment (GATE) can easily be adapted and applied to the Tether Dynamics Explorer (TDE) series. The GATE development schedule coincides with the planned first flight of the TDE. GATE technology has centered on the development of miniature deployers/actuators, sensors, control laws and simulation capability. The sensors currently under development are a tension sensor and a video based tether tracker. Both sensors are currently undergoing laboratory testing and development. The actuators currently being investigated are a small reel/deployed for active control of the tether and a small tether crawler to damp vibrations of the tether. Laboratory results are presented and the designs reviewed and discussed.

Greene, Michael↗
NASA NTRS1991

Derivation of mid-infrared (5-25 microns) optical constants of some silicates and palagonite

Recent reports concerning the mid-infrared reflectance properties of silicates coupled with recent observations of the Earth and other planets in the mid-infrared and the planned Thermal Emission Spectrometer scheduled as an instrument to be included on the Mars Observer all illustrate the increasing interest in the optical properties of materials in the mid-infrared and their direct application to remote sensing observations of other planetary surfaces. As the laboratory and observational data increase they will ultimately be modeled to aid in the understanding of the composition mineralogy, and distribution of the surface and atmospheric constituents on these bodies. In order to facilitate such quantitative analyses, knowledge regarding the optical constants (real (n) and imaginary (k) indices of refraction) of a wide variety of pertinent materials is required. Examples of the application of such quantitative analyses to the interpretation of Martian surface and atmospheric constituents, based on the optical constants of minerals, are presented. This study was initially conceived in order to aid in the interpretation of Martian surface and atmospheric aerosol mineralogy. As a result, the minerals included are biased toward samples which represent hydrated and hydroxylated silicates. These include the Al and Mg end members of the 1:1 layer lattice silicates, kaolinite and serpentine, respectively; an Al-bearing 2:1 layer lattice silicate, pyrophyllite; the Mg and Al smectite clays saponite and montmorillonite, respectively; and a palagonite, typically a poorly characterized alteration product of basaltic glass. The reflectivities of all samples were determined by placing them at the focus of a near-normal reflective attachment located in a Fourier transform spectrometer. To derive the optical constants of a material as a function of wavelength, researchers used the commonly employed technique of dispersion analysis.

Roush, T. L.↗
NASA NTRS1991

Resource allocation planning helper (RALPH)

The following topics are presented in view graph form: the background of the Resource Allocation Planning Helper (RALPH); RALPH schedule lifecycle; scheduling approach; technology layering; details; and RALPH directions.

Werntz, David G.↗
NASA NTRS1992

Polymer infiltration studies

Progress was made in several areas on the preparation of carbon fiber composites using advanced polymer resins. Polymer infiltration studies dealt with ways of preparing composite materials from advanced polymer resins and carbon fibers. This effort is comprised of an integrated approach to the process of composite part fabrication. The goal is to produce advanced composite materials for automated part fabrication using textile and robotics technology in the manufacture of subsonic and supersonic aircraft. The object is achieved through investigations at the NASA Langley Research Center and by stimulating technology transfer between contract researchers and the aircraft industry. Covered here are literature reviews, a status report on individual projects, current and planned research, publications, and scheduled technical presentations.

Marchello, Joseph M.↗
NASA NTRS1991

Future plans by the National Oceanic and Atmospheric Administration for operational geosynchronous weather satellites

The present status of the GOES program and plans for the GOES I-M system schedules for initial launch in 1992 are reviewed. Plans for improving NASA's capabilities to monitor weather patterns by using operational geosynchronous weather satellites are considered. The requirements for the imager, sounder, Space Environment Monitor, and Data Collection System of GOES-N are presented.

Gird, Ronald S.↗
NASA NTRS1992

Large project experiences with object-oriented methods and reuse

The SSVTF (Space Station Verification and Training Facility) project is completing the Preliminary Design Review of a large software development using object-oriented methods and systematic reuse. An incremental developmental lifecycle was tailored to provide early feedback and guidance on methods and products, with repeated attention to reuse. Object oriented methods were formally taught and supported by realistic examples. Reuse was readily accepted and planned by the developers. Schedule and budget issues were handled by agreements and work sharing arranged by the developers.

Wessale, William↗
NASA NTRS1999

Risk Reduction on X-33/RLV Engines

Risk management has received considerable attention in the X-33 and Reusable Launch Vehicle (RLV) program due to aggressive schedules, limited funding. and planned private investment to develop the commercial VentureStar vehicle. As an X-33 and RLV team member and main propulsion supplier, Boeing Rocketdyn Propulsion and Power has addressed risk through a methodical application of systems engineering in identifying, assessing, and mitigating risks. The methods employed involve rigorous risk mitigation planning early in development, continuous risk monitoring and assessment during the course of development, and the systematic verification of compliance with technical requirements prior to delivery. In addition, an engine system reliability analysis was conducted to reduce risk. In July 1996, NASA selected Lockheed Martin's "Skunk Works" (LMSW) as the lead contractor for the X-33 and RLV program. The X-33 vehicle is a half-scale pathfinder for the full-scale RLV. The LMSW RLV design is a lifting body shaped vehicle employing linear aerospike engine provided propulsion. The initial X-33 flight is planned for the summer of 2000, and the initial VentureStar flight is planned for between 2005 and 2007.

Crowley, Tim↗
NASA NTRS1999

SIRTF Science Operations System Design

SIRTF Science Operations System Design William B. Green Manager, SIRTF Science Center California Institute of Technology M/S 310-6 1200 E. California Blvd., Pasadena CA 91125 (626) 395 8572 Fax (626) 568 0673 bgreen@ipac.caltech.edu. The Space Infrared Telescope Facility (SIRTF) will be launched in December 2001, and perform an extended series of science observations at wavelengths ranging from 20 to 160 microns for five years or more. The California Institute of Technology has been selected as the home for the SIRTF Science Center (SSC). The SSC will be responsible for evaluating and selecting observation proposals, providing technical support to the science community, performing mission planning and science observation scheduling activities, instrument calibration during operations and instrument health monitoring, production of archival quality data products, and management of science research grants. The science payload consists of three instruments delivered by instrument Principal Investigators located at University of Arizona, Cornell, and Harvard Smithsonian Astrophysical Observatory. The SSC is responsible for design, development, and operation of the Science Operations System (SOS) which will support the functions assigned to the SSC by NASA. The SIRTF spacecraft, mission profile, and science instrument design have undergone almost ten years of refinement. SIRTF development and operations activities are highly cost constrained. The cost constraints have impacted the design of the SOS in several ways. The Science Operations System has been designed to incorporate a set of efficient, easy to use tools which will make it possible for scientists to propose observation sequences in a rapid and automated manner. The use of highly automated tools for requesting observations will simplify the long range observatory scheduling process, and the short term scheduling of science observations. Pipeline data processing will be highly automated and data-driven, utilizing a variety of tools developed at JPL, the instrument development teams, and Space Telescope Science Institute to automate processing. An incremental ground data system development approach has been adopted, featuring periodic deliveries that are validated with the flight hardware throughout the various phases of system level development and testing. This approach minimizes development time and decreases operations risk. This paper will describe the top level architecture of the SOS and the basic design concepts. A summary of the incremental development approach will be presented. Examples of the unique science user tools now under final development prior to the first proposal call scheduled for mid-2000 will be shown.

Green, William↗
NASA NTRS2000

Beyond Coordination: Joint Planning and Program Execution. The IHPRPT Materials Working Group

"Partnership is more than just coordination," stated then-Commander of the Air Force Research Laboratory (AFRL), Major General Dick Paul (USAF-Ret), at this year's National Space and Missile Materials Symposium. His comment referred to the example of the joint planning and program execution provided by the Integrated High Payoff Rocket Propulsion Technology (IHPRPT) Materials Working Group (IMWG). Most people agree that fiscal pressures imposed by shrinking budgets have made it extremely difficult to build upon our existing technical capabilities. In times of sufficient budgets, building advanced systems poses no major difficulties. However, with today's budgets, realizing enhanced capabilities and developing advanced systems often comes at an unaffordable cost. Overcoming this problem represents both a challenge and an opportunity to develop new business practices that allow us to develop advanced technologies within the restrictions imposed by current funding levels. Coordination of technology developments between different government agencies and organizations is a valuable tool for technology transfer. However, rarely do the newly developed technologies have direct applicability to other ongoing programs. Technology requirements are typically determined up-front during the program planning stage so that schedule risk can be minimized. The problem with this process is that the costs associated with the technology development are often borne by a single program. Additionally, the potential exists for duplication of technical effort. Changing this paradigm is a difficult process but one that can be extremely worthwhile should the right opportunity arise. The IMWG is one such example where NASA, the DoD, and industry have developed joint requirements that are intended to satisfy multiple program needs. More than mere coordination, the organizations comprising the group come together as partners, sharing information and resources, proceeding from a joint roadmap.

Stropki, Michael A.↗
NASA NTRS2002

Expedition 5 Crew Interviews: Valery Korzun, Commander

Expedition 5 Commander Valery Kozun is seen during a prelaunch interview. He gives details on the mission's goals and significance, his role in the mission and what his responsibilities will be as commander, what the crew exchange will be like (the Expedition 5 crew will replace the Expedition 4 crew on the International Space Station (ISS)), the daily life on an extended stay mission, the loading operations that will take place, the experiments he will be conducting on board, and the planned extravehicular activities (EVAs) scheduled for the mission. Kozun discusses the EVAs in greater detail and explains the significance of the Mobile Base System and the Crew Equipment Translation Aid (CETA) cart for the ISS. He also explains at some length the science experiments which will be conducted on board by the Expedition 5 crew members. Korzun also touches on how his previous space experience on Mir (including dealing with a very serious fire) will benefit the Expedition 5 mission.

Source record↗
NASA NTRS1990

Space Station Freedom Overview

This document explains which countries and agencies participate in the development of Space Station Freedom, what the different structures on the station will be, and who is responsible for constructing them. The systems which will be operational in the baseline configuration of the station are listed, as is its assembly schedule. An overview of plans for space station evolution is also given.

Kohrs, Richard H.↗
NASA NTRS2004

GUST LAT Multiwavelength Planning

Because gamma-ray astrophysics profits in powerful ways from multi-wavelength studies, the GLAST Large Area Telescope (LAT) Collaboration has started multiwavelength planning well before the scheduled 2007 launch. Many aspects of this program are of direct interest to observers using VERITAS and other atmospheric Cerenkov telescopes, whose capabilities complement those of GLAST. This talk with describe some of the current developmental concepts for GLAST LAT multiwavelength work, including release of data for transient sources, nearly-continuous monitoring of selected time-variable sources, pulsar timing, follow-on observations for source identification, coordinated blazar campaigns, and cross-calibration with other high-energy telescopes. Although few details are firm at this stage of preparation for GLAST, the LAT Collaboration looks forward to cooperation with a broad cross-section of the multiwave-length community. The GLAST Large Area Telescope is an international effort, with U.S. funding provided by the Department of Energy and NASA.

Thompson, D. J.↗
NASA NTRS2005

National Research Council Dialogue to Assess Progress on NASA's Title of CRM Capability Roadmap Development: General Background and Introduction

Contents include the following: General Background and Introduction of Capability Roadmaps "Title." Agency Objective. Strategic Planning Transformation. Advanced Planning Organizational Roles. Public Involvement in Strategic Planning. Strategic Roadmaps and Schedule. Capability Roadmaps and Schedule. Purpose of NRC Review. Capability Roadmap Development (Progress to Date).

Crooke, Julie A.↗
NASA NTRS2005

National Research Council Dialogue to Assess Progress on NASA's Advanced Modeling, Simulation and Analysis Capability and Systems Engineering Capability Roadmap Development

Contents include the following: General Background and Introduction of Capability Roadmaps. Agency Objective. Strategic Planning Transformation. Advanced Planning Organizational Roles. Public Involvement in Strategic Planning. Strategic Roadmaps and Schedule. Capability Roadmaps and Schedule. Purpose of NRC Review. Capability Roadmap Development (Progress to Date).

Aikins, Jan↗
NASA NTRS2005

National Research Council Dialogue to Assess Progress on NASA's Human Health & Support Systems Capability Roadmap Development: General Background and Introduction

Contents include the following: General Background and Introduction of Capability Roadmaps. Agency Objective. Strategic Planning Transformation. Advanced Planning Organizational Roles. Public Involvement in Strategic Planning. Strategic Roadmaps and Schedule. Capability Roadmaps and Schedule. Purpose of NRC Review. Capability Roadmap Development (Progress to Date).

Aikins, Jan↗