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Nasa - One of the best experts on this subject based on the ideXlab platform.

  • Fracture control requirements for payloads using the National Space Transportation System (NSTS)
    2019
    Co-Authors: Nasa
    Abstract:

    The purpose of this document is to establish the fracture control requirements for all payload hardware to be launched or retrieved using the National Space Transportation System (NSTS). Meeting these requirements implements the minimum fracture control requirements of NHB 1700.7, 'Safety Policy and Requirements for Payloads Using the Space Transportation System (STS).' All NSTS payload fracture control shall be in accordance with the requirements stated herein.

  • National Space Transportation System Reference. Volume 2: Operations
    2019
    Co-Authors: Nasa
    Abstract:

    An overview of the Space Transportation System is presented in which aspects of the program operations are discussed. The various mission preparation and prelaunch operations are described including astronaut selection and training, Space Shuttle processing, Space Shuttle integration and rollout, Complex 39 launch pad facilities, and Space Shuttle cargo processing. Also, launch and flight operations and Space tracking and data acquisition are described along with the mission control and payload operations control center. In addition, landing, postlanding, and solid rocket booster retrieval operations are summarized. Space Shuttle program management is described and Space Shuttle mission summaries and chronologies are presented. A glossary of acronyms and abbreviations are provided.

  • Space Transportation System Technology Symposium
    2019
    Co-Authors: Nasa
    Abstract:

    The prospect of undertaking a reusable launch vehicle development led the NASA Office of Manned Space Flight (OMSF) to request the Office of Advanced Research and Technology (OART) to organize and direct a program to develop the technology that would aid in selecting the best System alternatives and that would support the ultimate development of an earth-to-orbit shuttle. Such a Space Transportation System Technology Program has been initiated. OART, OMSF, and NASA Flight and Research Centers with the considerable inputs of Department of Defense personnel have generated the program through the efforts of several Technology Working Groups and a Technology Steering Group. Funding and management of the recommended efforts is being accomplished through the normal OART and OMSF line management channels. The work is being done in government laboratories and under contract with industry and universities. Foreign nations have been invited to participate in this work as well. Substantial funding, from both OART and OMSF, was applied during the second half of fiscal year 1970. The Space Transportation System Technology Symposium held at the NASA Lewis Research Center, Cleveland, Ohio, July 15-17, 1970, was the first public report on that program. The Symposium goals were to consider the technology problems, their status, and the prospective program outlook for the benefit of the industry, government, university, and foreign participants considered to be contributors to the program. In addition, it offered an opportunity to identify the responsible individuals already engaged in the program. The Symposium sessions were intended to confront each presenter with his technical peers as listeners, and this, I believe, was substantially accomplished. Because of the high interest in the material presented, and also because the people who could edit the output are already deeply involved in other important tasks, we have elected to publish the material essentially as it was presented, utilizing mainly the illustrations used by the presenters along with brief words of explanation. Those who heard the presentations, and those who are technically astute in specialty areas, can probably put this story together again. We hope that more will be gained by compiling the information in this form now than by spending the time and effort to publish a more finished compendium later.

  • Space Transportation System Thermal Environmental Flux Reference Book
    2014
    Co-Authors: Nasa
    Abstract:

    The information necessary to estimate the thermal environment in which proposed instruments will be expected to operate is presented in curves and tables which indicate the magnitude of the environmental fluxes which can be expected for various Space Transportation System missions.

  • Advanced Space Transportation System support contract
    2013
    Co-Authors: Nasa
    Abstract:

    The general focus is on a phase 2 lunar base, or a lunar base during the period after the first return of a crew to the Moon, but before permanent occupancy. The software effort produced a series of trajectory programs covering low earth orbit (LEO) to various node locations, the node locations to the lunar surface, and then back to LEO. The surface operations study took a lunar scenario in the civil needs data base (CNDB) and attempted to estimate the amount of Space-suit work or extravehicular activity (EVA) required to set up the base. The maintenance and supply options study was a first look at the problems of supplying and maintaining the base. A lunar surface launch and landing facility was conceptually designed. The lunar storm shelter study examined the problems of radiation protection. The lunar surface construction and equipment assembly study defined twenty surface construction and assembly tasks in detail.

R. A. Ahmad - One of the best experts on this subject based on the ideXlab platform.

  • Space Transportation System Launch Pad summer environmental effects
    1994
    Co-Authors: R. A. Ahmad
    Abstract:

    The external tank (ET) of the Space Transportation System (STS) contains liquid hydrogen as oxidizer and fuel for the Space Shuttle main engines. This article describes a two-dimensional flow and thermal forced convection analysis to determine solar effects on the Space Shuttle launch components subsequent to the ET loading operation in extremely hot conditions.

  • Space Transportation System launch pad summer environmental effects
    Journal of Thermophysics and Heat Transfer, 1994
    Co-Authors: R. A. Ahmad
    Abstract:

    The external tank (ET) of the Space Transportation System (STS) contains liquid oxygen and liquid hydrogen as oxidizer and fuel for the Space shuttle main engines. This article describes a two-dimensional flow and thermal forced convection analysis to determine solar heat effects on the Space shuttle launch components subsequent to the ET loading operation in extremely hot conditions. An existing computational fluid dynamics (CFD) code, parabolic hyperbolic or elliptical numerical integration code series (PHOENICS `81), was used in the study. The analysis was done for a two-dimensional slice between planes perpendicular to the longitudinal axis of the STS and passing through the lower portions of the redesigned solid rocket motors (RSRMs), the ET, and the orbiter wing. The results are presented as local and average values of surface temperatures and Nusselt numbers around the RSRMs and the ET. Solar heating effects increased surface temperatures of the RSRMs by 5-6.1 C. Comparisons were based on the local Nusselt number at the forward stagnation point and on the average Nusselt number around the West RSRM. 36 refs.

Russell E. Rhodes - One of the best experts on this subject based on the ideXlab platform.

  • Space Transportation System Availability Relationships to Life Cycle Cost
    45th AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2009
    Co-Authors: Russell E. Rhodes, Benjamin B. Donahue, Timothy T. Chen
    Abstract:

    Future Space Transportation architectures and designs must be affordable. Consequently, their Life Cycle Cost (LCC) must be controlled. For the LCC to be controlled, it is necessary to identify all the requirements and elements of the architecture at the beginning of the concept phase. Controlling LCC requires the establishment of the major operational cost drivers. Two of these major cost drivers are reliability and maintainability, in other words, the System’s availability (responsiveness). Potential reasons that may drive the inherent availability requirement are the need to control the number of unique parts and the spare parts required to support the Transportation System’s operation. For more typical Space Transportation Systems used to place satellites in Space, the productivity of the System will drive the launch cost. This System productivity is the resultant output of the System availability. Availability is equal to the mean uptime divided by the sum of the mean uptime plus the mean downtime. Since many operational factors cannot be projected early in the definition phase, the focus will be on inherent availability which is equal to the mean time between a failure (MTBF) divided by the MTBF plus the mean time to repair (MTTR) the System. The MTBF is a function of reliability or the expected frequency of failures. When the System experiences failures the result is added operational flow time, parts consumption, and increased labor with an impact to responsiveness resulting in increased LCC. The other function of availability is the MTTR, or maintainability. In other words, how accessible is the failed hardware that requires replacement and what operational functions are required before and after change-out to make the System operable. This paper will describe how the MTTR can be equated to additional labor, additional operational flow time, and additional structural access capability, all of which drive up the LCC. A methodology will be presented that provides the decision makers with the understanding necessary to place constraints on the design definition. This methodology for the major drivers will determine the inherent availability, safety, reliability, maintainability, and the life cycle cost of the fielded System. This methodology will focus on the achievement of an affordable, responsive Space Transportation System. It is the intent of this paper to not only provide the visibility of the relationships of these major attribute drivers (variables) to each other and the resultant System inherent availability, but also to provide the capability to bound the variables, thus providing the insight required to control the System’s engineering solution. An example of this visibility is the need to provide integration of similar discipline functions to allow control of the total parts count of the Space Transportation System. Also, selecting a reliability requirement will place a constraint on parts count to achieve a given inherent availability requirement, or require accepting a larger parts count with the resulting higher individual part reliability requirements. This paper will provide an understanding of the relationship of mean repair time (mean downtime) to maintainability (accessibility for repair), and both mean time between failure (reliability of hardware) and the System inherent availability.

  • Space Transportation Systems Life Cycle Cost Assessment and Control
    44th AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2008
    Co-Authors: John W. Robinson, Russell E. Rhodes, Edgar Zapata, Daniel J. H. Levack, Benjamin B. Donahue
    Abstract:

    Civil and military applications of Space Transportation have been pursued for just over 50 years and there has been, and still is, a need for safe, dependable, affordable, and sustainable Space Transportation Systems. Fully expendable and partially reusable Space Transportation Systems have been developed and put in operation that have not adequately achieved this need. Access to Space is technically achievable, but presently very expensive and will remain so until there is a breakthrough in the way we do business. Since 1991 the national Space Propulsion Synergy Team (SPST) has reviewed and assessed the lessons learned from the major U.S. Space programs of the past decades focusing on what has been learned from the assessment and control of Life Cycle Cost (LCC) from these Systems. This paper presents the results of a selected number of studies and analyses that have been conducted by the SPST addressing the need, as well as the solutions, for improvement in LCC. The major emphasis of the SPST processes is on developing the Space Transportation System requirements first (up front). These requirements must include both the usual System flight performance requirements and also the System functional requirements, including the infrastructure on Earth's surface, in-Space and on the Moon and Mars surfaces to determine LCC. This paper describes the development of specific innovative engineering and management approaches and processes. This includes a focus on flight hardware maturity for reliability, ground operations approaches, and business processes between contractor and government organizations. A major change in program/project cost control is being proposed by the SPST to achieve a sustainable Space Transportation System LCC - controlling cost as a program metric in addition to the existing practice of controlling performance and weight. Without a firm requirement and methodically structured cost control, it is unlikely that an affordable and sustainable Space Transportation System LCC will ever be achieved. '

  • Space Transportation System Availability Requirement and Its Influencing Attributes Relationships
    SpaceOps 2008 Conference, 2008
    Co-Authors: Russell E. Rhodes, Timothy C. Adams, Carey Mccleskey
    Abstract:

    It is important that engineering and management accept the need for an availability requirement that is derived with its influencing attributes. It is the intent of this paper to provide the visibility of relationships of these major attribute drivers (variables) to each other and the resultant System inherent availability. Also important to provide bounds of the variables providing engineering the insight required to control the System's engineering solution, e.g., these influencing attributes become design requirements also. These variables will drive the need to provide integration of similar discipline functions or technology selection to allow control of the total parts count. The relationship of selecting a reliability requirement will place a constraint on parts count to achieve a given availability requirement or if allowed to increase the parts count will drive the System reliability requirement higher. They also provide the understanding for the relationship of mean repair time (or mean down time) to maintainability, e.g., accessibility for repair, and both the mean time between failure, e.g., reliability of hardware and availability. The concerns and importance of achieving a strong availability requirement is driven by the need for affordability, the choice of using the two launch solution for the single Space application, or the need to control the spare parts count needed to support the long stay in either orbit or on the surface of the moon. Understanding the requirements before starting the architectural design concept will avoid considerable time and money required to iterate the design to meet the redesign and assessment process required to achieve the results required of the customer's Space Transportation System. In fact the impact to the schedule to being able to deliver the System that meets the customer's needs, goals, and objectives may cause the customer to compromise his desired operational goal and objectives resulting in considerable increased life cycle cost of the fielded Space Transportation System.

Edgar Zapata - One of the best experts on this subject based on the ideXlab platform.

  • Space Transportation Systems Life Cycle Cost Assessment and Control
    44th AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2008
    Co-Authors: John W. Robinson, Russell E. Rhodes, Edgar Zapata, Daniel J. H. Levack, Benjamin B. Donahue
    Abstract:

    Civil and military applications of Space Transportation have been pursued for just over 50 years and there has been, and still is, a need for safe, dependable, affordable, and sustainable Space Transportation Systems. Fully expendable and partially reusable Space Transportation Systems have been developed and put in operation that have not adequately achieved this need. Access to Space is technically achievable, but presently very expensive and will remain so until there is a breakthrough in the way we do business. Since 1991 the national Space Propulsion Synergy Team (SPST) has reviewed and assessed the lessons learned from the major U.S. Space programs of the past decades focusing on what has been learned from the assessment and control of Life Cycle Cost (LCC) from these Systems. This paper presents the results of a selected number of studies and analyses that have been conducted by the SPST addressing the need, as well as the solutions, for improvement in LCC. The major emphasis of the SPST processes is on developing the Space Transportation System requirements first (up front). These requirements must include both the usual System flight performance requirements and also the System functional requirements, including the infrastructure on Earth's surface, in-Space and on the Moon and Mars surfaces to determine LCC. This paper describes the development of specific innovative engineering and management approaches and processes. This includes a focus on flight hardware maturity for reliability, ground operations approaches, and business processes between contractor and government organizations. A major change in program/project cost control is being proposed by the SPST to achieve a sustainable Space Transportation System LCC - controlling cost as a program metric in addition to the existing practice of controlling performance and weight. Without a firm requirement and methodically structured cost control, it is unlikely that an affordable and sustainable Space Transportation System LCC will ever be achieved. '

  • Knowledge based representation and operations assessment of Space Transportation System architectures
    Knowledge-Based Systems, 2006
    Co-Authors: Alex J. Ruiz-torres, Edgar Zapata, Kazuo Nakatani, Marcella Cowen
    Abstract:

    Achieving the goals of safe and cost effective Space Transportation Systems requires the development of new methods and tools that allow leap-frog improvements in the conceptualization, design, development, production, and operation of these Systems. This paper reports on a modeling methodology aimed at the knowledge based representation and operational assessment of Space Transportation Systems to be used during early stages of design with the objective of improved design via estimation of their ground operations and performance. The model uses knowledge based logic and equations combined with a process database to determine the appropriate ground processes and their duration, allowing the estimation of operational measures of performance such as labor, cycle time, and flight rate.

Benjamin B. Donahue - One of the best experts on this subject based on the ideXlab platform.

  • Space Transportation System Availability Relationships to Life Cycle Cost
    45th AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2009
    Co-Authors: Russell E. Rhodes, Benjamin B. Donahue, Timothy T. Chen
    Abstract:

    Future Space Transportation architectures and designs must be affordable. Consequently, their Life Cycle Cost (LCC) must be controlled. For the LCC to be controlled, it is necessary to identify all the requirements and elements of the architecture at the beginning of the concept phase. Controlling LCC requires the establishment of the major operational cost drivers. Two of these major cost drivers are reliability and maintainability, in other words, the System’s availability (responsiveness). Potential reasons that may drive the inherent availability requirement are the need to control the number of unique parts and the spare parts required to support the Transportation System’s operation. For more typical Space Transportation Systems used to place satellites in Space, the productivity of the System will drive the launch cost. This System productivity is the resultant output of the System availability. Availability is equal to the mean uptime divided by the sum of the mean uptime plus the mean downtime. Since many operational factors cannot be projected early in the definition phase, the focus will be on inherent availability which is equal to the mean time between a failure (MTBF) divided by the MTBF plus the mean time to repair (MTTR) the System. The MTBF is a function of reliability or the expected frequency of failures. When the System experiences failures the result is added operational flow time, parts consumption, and increased labor with an impact to responsiveness resulting in increased LCC. The other function of availability is the MTTR, or maintainability. In other words, how accessible is the failed hardware that requires replacement and what operational functions are required before and after change-out to make the System operable. This paper will describe how the MTTR can be equated to additional labor, additional operational flow time, and additional structural access capability, all of which drive up the LCC. A methodology will be presented that provides the decision makers with the understanding necessary to place constraints on the design definition. This methodology for the major drivers will determine the inherent availability, safety, reliability, maintainability, and the life cycle cost of the fielded System. This methodology will focus on the achievement of an affordable, responsive Space Transportation System. It is the intent of this paper to not only provide the visibility of the relationships of these major attribute drivers (variables) to each other and the resultant System inherent availability, but also to provide the capability to bound the variables, thus providing the insight required to control the System’s engineering solution. An example of this visibility is the need to provide integration of similar discipline functions to allow control of the total parts count of the Space Transportation System. Also, selecting a reliability requirement will place a constraint on parts count to achieve a given inherent availability requirement, or require accepting a larger parts count with the resulting higher individual part reliability requirements. This paper will provide an understanding of the relationship of mean repair time (mean downtime) to maintainability (accessibility for repair), and both mean time between failure (reliability of hardware) and the System inherent availability.

  • Space Transportation Systems Life Cycle Cost Assessment and Control
    44th AIAA ASME SAE ASEE Joint Propulsion Conference & Exhibit, 2008
    Co-Authors: John W. Robinson, Russell E. Rhodes, Edgar Zapata, Daniel J. H. Levack, Benjamin B. Donahue
    Abstract:

    Civil and military applications of Space Transportation have been pursued for just over 50 years and there has been, and still is, a need for safe, dependable, affordable, and sustainable Space Transportation Systems. Fully expendable and partially reusable Space Transportation Systems have been developed and put in operation that have not adequately achieved this need. Access to Space is technically achievable, but presently very expensive and will remain so until there is a breakthrough in the way we do business. Since 1991 the national Space Propulsion Synergy Team (SPST) has reviewed and assessed the lessons learned from the major U.S. Space programs of the past decades focusing on what has been learned from the assessment and control of Life Cycle Cost (LCC) from these Systems. This paper presents the results of a selected number of studies and analyses that have been conducted by the SPST addressing the need, as well as the solutions, for improvement in LCC. The major emphasis of the SPST processes is on developing the Space Transportation System requirements first (up front). These requirements must include both the usual System flight performance requirements and also the System functional requirements, including the infrastructure on Earth's surface, in-Space and on the Moon and Mars surfaces to determine LCC. This paper describes the development of specific innovative engineering and management approaches and processes. This includes a focus on flight hardware maturity for reliability, ground operations approaches, and business processes between contractor and government organizations. A major change in program/project cost control is being proposed by the SPST to achieve a sustainable Space Transportation System LCC - controlling cost as a program metric in addition to the existing practice of controlling performance and weight. Without a firm requirement and methodically structured cost control, it is unlikely that an affordable and sustainable Space Transportation System LCC will ever be achieved. '