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The prediction of vehicle temperatures during ascent through the earth’s atmosphere requires an accurate knowledge of the aerodynamic heating rates occurring at the vehicle surface. Flight parameters required in heating calculations include the local airstream velocity, pressure, and temperature at the boundary layer edge for the vehicle location in question. In addition, thermodynamic and transport air properties are required at these conditions. Both laminar and turbulent boundary layers occur during the boost trajectory. Experience has shown that laminar and turbulent heating are of equivalent importance. Laminar heating predominates in importance in the stagnation areas, but the large afterbody surfaces are most strongly affected by turbulent heating. Once the local flow conditions and corresponding air properties have been obtained, the convective heating rate may be calculated for a particular wall temperature.

The prediction of vehicle temperatures during ascent through the earth’s atmosphere requires an accurate knowledge of the aerodynamic heating rates occurring at the vehicle surface. Flight parameters required in heating calculations include the local airstream velocity, pressure, and temperature at the boundary layer edge for the vehicle location in question. In addition, thermodynamic and transport air properties are required at these conditions. Both laminar and turbulent boundary layers occur during the boost trajectory. Experience has shown that laminar and turbulent heating are of equivalent importance. Laminar heating predominates in importance in the stagnation areas, but the large afterbody surfaces are most strongly affected by turbulent heating. Once the local flow conditions and corresponding air properties have been obtained, the convective heating rate may be calculated for a particular wall temperature.

The Engineering Analysis SYstem (EASY) computer program is summarized in this report. It provides techniques for analysis of steady-state and dynamic (transient) environmental control system (ECS) performance, control system stability, and for synthesis of optimal ECS. General uses of a transient analysis computer program for ECS design and development, and general features of EASY relative to these uses, are presented. This report summarizes the nine analysis options of EASY, EASY program organization for analyzing ECS, data input to the program and resulting data output, and a discussion of EASY limitations. Appendices provide general definitions for dynamic analysis, and samples of input and output for EASY.

The Environmental Control Analysis SYstem (EASY) computer program is summarized in this report. Development of this computer program initially was sponsored by the U.S. Air Force Flight Dynamics Laboratory. (See References 1, 2, 3, and 4.) It provides techniques for determination of steady state and dynamic (transient) ECS performance, and of control system stability; and for synthesis of optimal ECS control systems. The program is available from the U.S. Air Force, or as a proprietary commercial version. General uses of a transient analysis computer program for ECS design and development, and general features of EASY relative to these uses, are presented. This report summarizes the nine analysis options of EASY, EASY program organization for analyzing ECS, data input to the program and resulting data output, and a discussion of EASY limitations. Appendices provide general definitions for dynamic analysis, and samples of input and output for EASY.

This AIR is arranged in the following four sections: 2A - Properties of the Natural Environment 2B - Properties of Gases 2C - Properties of Liquids 2D - Properties of Solids A summary of each section is given below. Section 2A - This section includes currently applicable earth atmosphere standards (Refs. 101 and 103) and data on the near-Earth environment. Limited data on Mars and Venus reflected solar and planetary-emitted radiation and on micrometeorite data are also included. For space vehicle applications, environmental models are of two general types: orbital and reentry. For orbital models, variable properties such as time and solar flux are usually averaged. Reentry atmospheres are chiefly a function of location and altitude, and selection may be based on reentry location. Variation with latitude is an important local effect (Ref. 106). The electromagnetic solar radiation data in this section are for altitudes above the Earth’s atmosphere.

This AIR is arranged in the following four sections: 2A - Properties of the Natural Environment 2B - Properties of Gases 2C - Properties of Liquids 2D - Properties of Solids A summary of each section is given below.

This Aerospace Recommended Practice outlines the design, installation, testing and field maintenance criteria for aerospace vehicle cryogenic duct systems. These recommendations are considered currently applicable guides and are subject to revision due to the continuing development within industry.

This SAE Aerospace Information Report (AIR) provides information on aircraft cabin air quality, including: Airborne contaminant gases, vapors, and aerosols. Identified potential sources. Comfort, health and safety issues. Airborne chemical measurement. Regulations and standards. Operating conditions and equipment that may cause aircraft cabin contamination by airborne chemicals (including Failure Conditions and normal Commercial Practices). Airborne chemical control systems. It does not deal with airflow requirements.

This SAE Aerospace Information Report (AIR) provides information on aircraft cabin air quality, including: Origins of chemical airborne contaminants during routine operating and failure conditions. Exposure control measures, including design, maintenance, and worker training/education. This AIR does not deal with airflow requirements.