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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.

Heat dissipated in conduction cooled spacecraft components must be transported across the component base plate/spacecraft mounting plate interface preparatory to final radiation to the space sink.

Several areas for improvement in the thermal and mechanical properties of the passive thermal control optical solar reflectors (OSRs) have been identified and discussed in a previous paper (1). These include the use of specialised optical coatings to optimise the emittance and absorptance of OSRs and also chemical treatments to provide greater resistance to handling and better conductivity where necessary. Each of the proposed techniques have been demonstrated and the most promising have been incorporated into development programmes leading to production. In parallel with this activity, examination of aspects of the whole passive thermal control system, in terms of optimal construction and assembly, and thermal and conductive properties is expected to commence shortly. It is anticipated that these will result in the specification and use of optimal thermal control systems for future satellites.

The Spacecraft Radiative Thermal Model Exchange System is a technology developed for the bi-directional exchange of spacecraft radiative thermal models via the TMG thermal software package. ...The Spacecraft Radiative Thermal Model Exchange System is a technology developed for the bi-directional exchange of spacecraft radiative thermal models via the TMG thermal software package. It provides a means for quickly and accurately transferring models between TMG and theree of the major thermal radiation codes used in the spacecraft industry, particularly the ESARAD and Thermica packages, which are widely used by contractors to the European Space Agency, and the TSS code which is prevalent in the United States space industry. ...It provides a means for quickly and accurately transferring models between TMG and theree of the major thermal radiation codes used in the spacecraft industry, particularly the ESARAD and Thermica packages, which are widely used by contractors to the European Space Agency, and the TSS code which is prevalent in the United States space industry.

This paper attempts to expand the knowledge in beryllium mechanical joining technology to develop a structural and fabrication confidence level in utilizing solid shank and blind rivet fasteners in assembling beryllium spacecraft structures.

In 1998, the first element of the Earth Observing System, the EOS-AM1 spacecraft, will be launched into a sun-synchronous polar orbit. The EOS-AM1 platform will include five instruments that will form the payload used to provide information on global climate change. ...The EOS-AM1 platform will include five instruments that will form the payload used to provide information on global climate change. The spacecraft will also include a dual frequency (Ku- and S-band) High Gain Antenna (HGA) which will serve as the primary system for transmitting the science data and spacecraft telemetry & command data to the ground via the TRDSS (Tracking and Data Relay Satellite System) network. ...The spacecraft will also include a dual frequency (Ku- and S-band) High Gain Antenna (HGA) which will serve as the primary system for transmitting the science data and spacecraft telemetry & command data to the ground via the TRDSS (Tracking and Data Relay Satellite System) network.

This paper describes the continued development of a membrane-based subsystem designed to recover up to 99.5% of the water from various spacecraft waste waters. Specifically discussed are 1) the design and fabrication of an energy-efficient reverse-osmosis (RO) breadboard subsystem; 2) data showing the performance of this subsystem when operated on a synthetic wash-water solution-including the results of a 92-day test; and 3) the results of pasteurization studies, including the design and operation of an in-line pasteurizer.

Vapor Compression Distillation technology has proved its readiness as a spacecraft wastewater processor as evidenced by selection of this technology for the Urine Processor Assembly aboard Space Station Freedom.

A need exists for a controlled, clean rigidization technology to harden inflatable spacecraft once they have achieved the required shape. This study addressed the space environment for typical orbits, development of UV curing cationic epoxy resin systems, mechanical properties of UV cured composites, and fabrication of demonstration tubes using the photocurable resin technology.

As assembly of the International Space Station (ISS) proceeds, predictive techniques are used to determine the best approach for handling a variety of cabin air quality challenges. These techniques use equipment offgassing data collected from each ISS module before flight to characterize the trace chemical contaminant load. Combined with crew metabolic loads, these data serve as input to a predictive model for assessing the capability of the onboard atmosphere revitalization systems to handle the overall trace contaminant load as station assembly progresses. The techniques for predicting in-flight air quality are summarized along with results from early ISS mission analyses. Results from ground-based analyses of in-flight air quality samples are compared to the predictions to demonstrate the technique’s relative conservatism.

The development of this computerized system was sponsored by NASA specifically for the Acceptance Checkout Equipment for the Apollo Spacecraft (or ACE-S/C). This checkout equipment is being used to monitor Apollo Spacecraft performance at the Grumman facility at Bethpage, Long Island; at the NAA facility at Downey, California; at the Manned Spacecraft Center at Houston, Texas; and at the NASA Merritt Island complex at Cape Kennedy. ...This checkout equipment is being used to monitor Apollo Spacecraft performance at the Grumman facility at Bethpage, Long Island; at the NAA facility at Downey, California; at the Manned Spacecraft Center at Houston, Texas; and at the NASA Merritt Island complex at Cape Kennedy. Although the computerized system was designed for a specific hardware project, the surveillance and product improvement tools used are of such a generalized nature that they would be applicable in other hardware projects, whether intended for earth or space applications.

The temperature predictions of many scanner components in the original thermal model had poor agreement with the spacecraft and instrument integrated sun-pointing safehold (SPSH) thermal balance (T/B) test results. ...The temperature predictions of many scanner components in the original thermal model had poor agreement with the spacecraft and instrument integrated sun-pointing safehold (SPSH) thermal balance (T/B) test results. The spacecraft and instrument integrated T/B test led to a change of the Full Aperture Calibrator (FAC) motor stack “solar shield” coating from MIL-C-5541 to multi-layer insulation (MLI) thermal blanket. ...The flight temperature predictions in the nominal 15-orbit mission profile, plus margins, were used as the yellow limits for most of the ETM+ components. The spacecraft and instrument integrated T/B and T/V test also revealed that the standby heater capacity on the Scan Mirror Assembly (SMA) was insufficient when the Earth Background Simulator (EBS) was 15°C or colder, and the baffle heater possibly caused the coherent noise in the narrow band data when it was on.

Microbial biofilms representing both Gram-positive and Gram-negative bacteria were artificially coated onto aluminum metal surfaces that are commonly used in building spacecraft. Changes in bacterial numbers were monitored over time on metal test sections by conventional spread plate technique and polymerase chain reaction (PCR). ...In ongoing investigations to map and archive the microbial footprints in various components of spacecraft and its accessories, we examined the microbial populations of the JPL-Spacecraft Assembly Facility (SAF). ...We exposed witness plates that are made up of spacecraft materials and/or painted with spacecraft-quality paints for ~7 to 9 months. In the initial studies reported here, we examined the total cultivable aerobic heterotrophs.

Catalytic combustion coupled with activated carbon and molecular sieve adsorbents is applicable to all areas of air and gas clean up ranging from high to low levels of pollutants and trace contaminants control in a spacecraft environment is of no exception. In this study we propose a combined activated charcoal and catalytic combustion system based on a 70 watt power input achieving 350°C, operating on a 6 hour per 24 hour day catalytic cycle with an actual flow of 10.6 l min-1 in a residual free volume of 60 m3.

Measurement of thermal emittance of hardanodized coating on aluminium sample at different temperatures from −80°C to +100°C has been made using steady state calorimetric method. The measurement sample consists of two aluminium circular discs hardanodized on all surfaces except on assembly contact areas. A thin circular heater was sandwiched between the discs. The assembled sample was suspended inside a vacuum chamber with LN2 cooled shroud and maintained at different temperature levels using electrical power. The thermal emittance of the sample is determined from the sample equilibrium temperatures and from the elect rical power input. An error estimation has been performed, it shows a maximum uncertainty of ±3.3% on the emittance.

The first element of the International Space Station (ISS), Zarya, was funded by NASA and built by the Russian aerospace company Khrunichev State Research and Production Space Center (KhSC). NASA Glenn Research Center (GRC) and KhSC collaborated in performing analytical predictions of the on-orbit electrical performance of Zarya’s solar arrays. GRC assessed the pointing characteristics of and shadow patterns on Zarya’s solar arrays to determine the average solar energy incident on the arrays. KhSC used the incident energy results to determine Zarya’s electrical power generation capability and orbit-average power balance. The power balance analysis was performed over a range of solar beta angles and vehicle operational conditions. This analysis enabled identification of problems that could impact the power balance for specific flights during ISS assembly and was also used as the primary means of verifying that Zarya complied with electrical power requirements.

Novel mesoporous bimetallic oxidation catalysts are described, which are currently under development for the deep oxidation (mineralization) of aqueous organic contaminants in wastewater produced on-board manned spacecraft, and lunar and planetary habitats. The goal of the ongoing development program is to produce catalysts capable of organic contaminant mineralization near ambient temperature.

This report describes the design, assembly, and testing of a modified, re-circulating drip flow reactor to quantify the electrical, optical, and thermal performance of solid-state ultraviolet (UV) lighting and semi-conducting photocatalyst for potable water disinfection by advanced oxidation processes. The reactor test assembly incorporates high-output UV-A Light Emitting Diodes (LEDs) with active thermal control to reject heat and generate reactive oxygen species from immobilized titanium dioxide attached to borosilicate glass in the laminar flow stream. Compared with UV-excimer and UV-mercury arc lamps, the UV-A LED system demonstrated excellent thermal stability and good electrical and optical performance.

A failure during the Liquid Apogee Engine (LAE) firing with Thermal Shield, forced Selenia Spazio to critically review the thermal design concept of the LAE/Shield Assembly of ITALSAT Program. This review led to: the change of Thermal Shield design criteria (in order to increase the safety margin on the LAE firing temperatures); the identification of thermal failure modes of the utilized LAE (together with the contribution of many other US and European LAE utilizers and of LAE Supplier as well); the definition and implementation of a LAE Firing Control Strategy. This Paper describes the performed efforts and the resulting engineering considerations.

Technicians and engineers from Lockheed Martin, NASA, and supporting contractors meticulously assembled the capsule into its finished state, including installing the capsule's avionic computers, harnesses, propulsion system and its 12 engines, 11 parachutes, its large 16-foot-diameter heat shield, and forward bay cover.