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In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. ...In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. The spacecraft thermal balance between cold space and solar, planetary, and equipment heat sources is the means by which the desired range of equipment and structural temperatures are obtained. ...With the total spacecraft balance set, subsystem and component temperatures can be analyzed for their corresponding thermal requirements.

This part of the manual presents methods for arriving at a solution to the problem of spacecraft inflight equipment environmental control. The temperature aspect of this problem may be defined as the maintenance of a proper balance and integration of the following thermal loads: equipment-generated, personnel-generated, and transmission through external boundary.

A life support system (LSS) is usually defined as a system that provides elements necessary for maintaining human life and health in the state required for performing a prescribed mission. The LSS, depending upon specific design requirements, will provide pressure, temperature, and composition of local atmosphere, food, and water. It may or may not collect, dispose, or reprocess wastes such as carbon dioxide, water vapor, urine, and feces. It can be seen from the preceding definition that LSS requirements may differ widely, depending on the mission specified, such as operation in Earth orbit or lunar mission. In all cases the time of operation is an important design factor. An LSS is sometimes briefly defined as a system providing atmospheric control and water, waste, and thermal management.

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.

Space applications include spacecraft, such as satellites, space stations, launch vehicles and space shuttles, and servicing equipment and components used for ground systems and launching and for servicing in space.

This SAE Metric Aerospace Recommended Practice (MAP) establishes the requirements for preparing a specification for fluid couplings for spacecraft servicing. The objective of this document is to provide design, development, verification, storage, and delivery requirement guidelines for the preparation of specifications for fluid couplings and the ancillary hardware for use with serviceable spacecraft designed for use in the space environment. ...The objective of this document is to provide design, development, verification, storage, and delivery requirement guidelines for the preparation of specifications for fluid couplings and the ancillary hardware for use with serviceable spacecraft designed for use in the space environment. The couplings shall be capable of resupplying storable propellants, cryogenic liquids, and gases to a variety of spacecrafts. ...The couplings shall be capable of resupplying storable propellants, cryogenic liquids, and gases to a variety of spacecrafts.

Several research programs which have applied thermal scale modeling to a radiation-conduction heat transfer system (unmanned spacecraft) and to a radiation-conduction-convection heat transfer system (manned spacecraft) are reviewed and evaluated. ...The utilization of scaled models in the development of spacecraft thermal control systems is discussed. The criteria necessary to establish thermal similitude are developed as well as techniques for designing scaled thermal models.

An evolutionary survey of spacecraft landing systems with mission requirements and landing system performance as the evolutionary yardstick is presented. ...The conclusions contain a prognosis of what the next decade may hold for spacecraft landing systems and indicate areas wherein continued improvement is highly desirable.

The functions performed by pyrotechnic systems and devices in the Apollo spacecraft during a lunar exploration mission and in aborts are presented. The devices and systems are described. ...The modular cartridge concept and the standard electroexplosive device used throughout the spacecraft are innovations and are discussed in detail. Some of the techniques used to attain the high levels of reliability, to assure crew safety, to control quality, and to eliminate human errors are briefly presented.

A detailed account of the development and use of bladders in Ranger and Mariner spacecraft is presented. The final section describes an advanced development program aimed at providing technology for future spacecraft. ...The final section describes an advanced development program aimed at providing technology for future spacecraft.

The large difference between the total numbers of manned and unmanned spacecraft and their respective missions is discussed. The environmental and functional requirements having different effects on the two spacecraft types are described. ...The environmental and functional requirements having different effects on the two spacecraft types are described. The materials characteristics involved in those requirements and the resulting typical configurations are reviewed. ...It is concluded that vibration and pressurized gas containment have the outstanding influence on spacecraft structural systems. It is noted that new structural factors of safety have not been derived on the basis of any rational consideration of the design conditions for stability or pressure critical structure.

Because of the capability of extended accuracy, digital systems are indicated for guidance and control of spacecraft. Furthermore, by implementing these systems with integrated microelectronic components, substantial improvement in reliability can be expected. ...A study and experimental evaluation program was performed to apply such digital techniques to the spacecraft stabilization and control problem. Of major consideration were the selection of appropriate mathematical techniques for system analysis and the development of suitable fabrication methods for hardware implementation. ...A discrete state model of a spacecraft reaction wheel and jet attitude control system was developed and computer simulations were performed.

The design of a spacecraft requires performing of a series of trade-offs, either at component level, sub-system or system level. ...This paper aims to focus the attention of space engineers on the detailed definition and choice of temperature sensors for spacecraft applications. Although the use of previous experiences and lessons-learned should be taken into consideration, the “already flown before” philosophy (If it has flown before in design-X then it has to work in our design-Y!!)

These neutrons are produced from several sources: from the terrestrial albedo and as secondary particles produced by the interaction of cosmic rays, solar protons and trapped protons with the material of the spacecraft. Recently, neutrons have also been observed originating in solar flares, at the solar surface. ...Theoretical estimates and experimental measurements of the neutron fluxes inside manned spacecraft in near-Earth orbit are reviewed and discussed. The anticipated neutron fluxes and their resulting dose-equivalents, as a function of shielding depth for exploration class missions, are presented and discussed.

The mission consists of three spacecraft which will accurately monitor the variations in the Earth's magnetic field. This leads to constraints, for the Thermal Control Sub-System, on the selection of thermal finishes and in the selection of heater mats. ...This paper discusses the thermal design of the SWARM spacecraft and how the difficult issues were overcome.

The MUSES-B spacecraft will be launched in 1996 by the Institute of Space and Astronautical Science (ISAS). ...The thermal design and verification has been performed separately for the major modules of the spacecraft; a main structure, a deployable antenna and Reaction Control System (RCS). Special attention is paid to the exposed RCS whose solar input varies significantly depending on the sun angle.

How much integrated system level test should be performed on a spacecraft before it is launched? Although sometimes system test is minimized, experience shows that systems level testing should be thorough and complete. ...Human-rated spacecraft test planning is informal, subjective, and inconsistent, and its extent is often determined by the decision maker's risk tolerance, decision-making style, and long-term or short-term view.

It is therefore imperative to develop a safe, effective method of microbial control. Spacecraft application dictates a more stringent set of requirements for biocide selection than is usually necessary for terrestrial situations. ...Toxicity of the biocide is the driving factor for disinfectant choice in spacecraft. This concern greatly reduces the number and types of chemical agents that can be used as disinfectants. ...Furthermore, the chemical and toxicological properties of these biocides and others are considered in relation to disinfection of spacecraft and allied hardware.

Radarsat is a Canadian remote sensing satellite designed to gather earth resource data from a low earth orbit. The spacecraft consists of four major entities: the payload module, the bus module, the SAR antenna and the solar arrays.