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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.

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.

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.

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.

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.

Vacuum and radiation conditions in space are discussed, as these appear to cause the major limitations on lubrication for spacecraft equipment. While many lubricants suffer a drastic loss in lifetime as a result of these environments, experimental studies have demonstrated that certain oils and greases can lubricate lightly loaded ball bearings without replenishment for periods of two years and more under the following conditions of operation: speeds of 8000 rpm, temperatures of 160 to 200 F, and vacuum of 10−8 torr.

This paper highlights the role of electrochemical processes in spacecraft environmental systems development and, by example, describes the fundamentals of these processes.

A method that exploits certain properties of a recirculating gas has been investigated as a means of achieving a sustained accelerative vector force without either the expulsion of mass from or a reaction against an external mass by the accelerated body. A theory of operation is presented that defines the capabilities and limitations of the method, and which has resulted in functioning prototypes. The prototype devices require only a source of electric power and a means of cooling to achieve an internally generated, externally measurable accelerative vector force that is sustained for as long as power is supplied to the device.

Research in microgravity (low-gravity) combustion promises innovations and improvements in fire prevention and response for human-crew spacecraft. Findings indicate that material flammability and fire spread in microgravity are significantly affected by atmospheric flow rate, oxygen concentration, and diluent composition. ...Research on smoke-particle changes in microgravity promises future improvements and increased sensitivity of smoke detectors in spacecraft. Research on fire suppression by extinguishing agents and venting can yield new information on effective control of the rare, but serious fire events in spacecraft. ...Research on fire suppression by extinguishing agents and venting can yield new information on effective control of the rare, but serious fire events in spacecraft.

In recent years, with the advent of large spacecraft, thermal balance testing techniques using infrared lamp sources have become increasingly attractive. ...In addition to cost savings, the IR technique is more versatile in terms of spacecraft orientation and supplied flux conditions. Because of the differences between solar illumination and IR simulation the IR lamp flux characteristics must be accurately determined. ...The radiation absorbed by spacecraft surfaces under test conditions can be obtained from a computer code incorporating lamp arrays, specular baffles and surface property variations with lamp power level and radiation angle of incidence.

Followed by brief discussions of the primary natural particle radiation sources and the operational sensitivities imposed by them on crew and spacecraft, the analytical system and methods are described. The use of this automated analytical tool called Brem (Boeing radiation exposure model), is then addressed regarding spacecraft design and the optimization of radiation shielding. ...The use of this automated analytical tool called Brem (Boeing radiation exposure model), is then addressed regarding spacecraft design and the optimization of radiation shielding.

The Ranger Telerobotic Flight Experiment is a highly complex teleoperated spacecraft, requiring direct human control of 36 major degrees of freedom. The University of Maryland Space Systems Laboratory and the NASA Ames Research Center are cooperating on the development of a virtual reality control station to streamline human interfaces with the Ranger spacecraft. ...The University of Maryland Space Systems Laboratory and the NASA Ames Research Center are cooperating on the development of a virtual reality control station to streamline human interfaces with the Ranger spacecraft. This describes the design and integration of the Ranger Command Chair, a system incorporating fully immersive helmet-mounted stereo displays with head tracking, hand tracking for direct positional control, and supplemental controls and displays to allow a single operator to functionally control the entire vehicle.

(ADA) is developing a handheld fine water mist fire extinguisher for use on manned spacecraft and in future planetary habitats. This design employs only water and nitrogen as suppression agents to allow local refill and reuse. ...Continued development will result in prototype hardware suitable for use on future manned spacecraft.

Experience with free-flying space payloads in the current era of reduced budgets has led to a continuing need for an easier-to-use and more cost-effective capability for spacecraft thermal analyses. Preliminary thermal design of the MSX spacecraft has been developed using an 80386-based MS-DOS microcomputer. ...These programs provide both an interactive geometry editor and a graphical representation of the current spacecraft geometry. The output of VIEWI is converted to a SSPTA2 geometry input file. SSPTA, a software package that simplifies the procedures for conducting sophisticated thermal analyses of orbiting payloads, consists of CONSHAD, a view factor calculation program, SCRIPTF, a radiation conductance calculation program, ORBITAL, a satellite orbital heat flux program, and ABSORB, a program to calculate absorbed power.

There are not only large amounts of energy, but also many different kinds of energy in manned spacecraft, which provide chance to optimize a thermal management system in the spacecraft. When water in atmosphere in pressured cabins was removed, waste heat in atmosphere was removed synchronously.

To provide spacecraft thermal design engineers with the data needed to define the earth albedo and emission, we have analyzed data from the Earth Radiation Balance Experiment (ERBE) over a period of 36 months, covering orbital inclinations of 57 and 99 degrees.

Thermal conductances are computed for relatively simple node geometries that are typical of analytical models of spacecraft. Heat-transfer rates computed with these conductances are compared to heat-transfer rates computed from exact, closed-form mathematical formulas.

NASA's Earth Observing System (EOS) Program will place a series of unmanned polar-orbiting spacecraft in low-earth orbit to support a variety of scientific and Earth-observing missions. The EOS AM spacecraft has a requirement for an advanced heat transportation system for thermal energy. ...The EOS AM spacecraft has a requirement for an advanced heat transportation system for thermal energy. A Capillary Pumped Heat Transportation System (CPHTS) using Capillary Pumped Loop (CPL) technology was selected to accommodate the instruments requiring advanced heat transport.

Spacecraft have previously used passive cooling or pumped liquid loops to maintain proper thermal environments. ...Future large spacecraft, such as the Space Station, will have higher power levels and longer heat transport distances.