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An advanced development helmet mounted display (HMD) was designed and fabricated under NASA-Johnson Space Center (NASA/JSC) contract, NAS 9-17543, by Hamilton Standard Division of United Technologies, Windsor Locks, CT. The work was initiated in December 1985 and culminated in June 1988 with the delivery of an extravehicular mobility unit (EMU) HMD demonstration unit as an alternative to the current low-resolution, chest-mounted display and cuff-mounted checklists. Important design goals achieved with this HMD include the use of transmissive liquid crystal display (LCD) image sources with fairly high resolution (i.e., text, graphics, and video compatible), binocular viewing with total image overlap, virtual image projection, low profile packaging, low power design, and demonstration of voice control of the HMD data.

Most of the studies conducted on the design of inflated fabric structures for space applications have focused on types of yarns and coating selection. The design of seams along with materials selection considerations is also crucial to the design of inflatable structures. This paper presents a pilot study of the modes of failure for fabrics with two selected sewn seams under biaxial stress loading. A literature review of sewn seam testing techniques reveals that conventional methods do not accurately simulate the biaxial stresses to which inflated fabrics are subjected. In this study, biaxial stresses are obtained by using a cylindrical pressure testing apparatus developed originally for testing seam design for an inflatable Lunar habitat. The unique features of the test method for sewn seams of fabrics by cylindrical pressure loading are described. Test data is presented, and the sensitivity of the test to changes is also discussed.

The Crew Exploration Vehicle (CEV) is the first crew transport vehicle to be developed by the National Aeronautics and Space Administration (NASA) in the last thirty years. The CEV is being developed to transport the crew safely from the Earth to the International Space Station and then later, from the Earth to the Moon . This year, the vehicle continued to go through design refinements to reduce weight, meet requirements, and operate reliably while preparing for Preliminary Design Review in the summer of 2009. The design of the Orion Environmental Control and Life Support (ECLS) system, which includes the life support and active thermal control systems, is progressing through the design stage. This paper covers the Orion ECLS development from April 2008 to April 2009.

The Extravehicular Mobility Unit (EMU) used by astronauts during space walks is powered by an 11-cell, silver-zinc battery. The present battery is certified for 6 cycles with a minimum discharge requirement of 7 hours above 16.0 volts at a 3.8 Amp load. Its certified wet-life is 170 days. Operational requirements for the International Space Station (ISS) led to a design capable of 32 cycles over a 425 day wet-life. Other battery parameters including capacity, rate capability, weight, volume, safety and the need for continuing compatibility with the EMU and the Space Shuttle charger dictate that the new battery will also be silver-zinc.

The Crew and Thermal Systems Division (CTSD) at NASA's Johnson Space Center under the support of the Office of Life and Microgravity Sciences and Applications is conducting the Early Human Testing Initiave (EHTI) project with the goal of validating regenerative life support technologies through a series of integrated tests with human subjects. The EHTI project is organized into three distinct phases, each with progressively more complex integration of biological and physicochemical (P/C) life support technologies. The goal of Phase I is to conduct a 15-day one-person test to verify the performance of an air revitalization system based on higher plants with physicochemical systems as complements and backups. The test will be performed in CTSD's Variable Pressure Growth Chamber (VPGC), a tightly closed controlled-environment test chamber configured with approximately 11 m2 of area for plant growth.

Water transferred from the Space Shuttle to the International Space Station (ISS) is generated as a by-product from the Shuttle fuel cells, and is generally preferred over the Progress which has to launch water from the ground. However, launch mass and volume are still required for the transfer and storage hardware. Some of these up-mass requirements have been reduced since ISS assembly began due to changes in the storage hardware (CWC). This paper analyzes the launch mass and volume required to transfer water from the Shuttle and analyzes the up-mass savings due to modifications in the CWC. Suggestions for improving the launch mass and volume are also provided.

An experiment was performed to observe flow regimes and measure pressure drops of two-phase (liquid/vapor) flow and condensation in reduced gravity. Testing was conducted aboard the NASA-JSC KC-135 reduced gravity aircraft using a prototype two-phase thermal management system for large spacecraft. A clear section of two-phase line enabled visual and photographic observation of the flow regimes. The two-phase mixture was generated by pumping nearly saturated liquid refrigerant 114 through an evaporator and adding heat through electric heaters. The resultant two-phase flow was varied by changing the evaporator heat load, creating qualities from 0.05 to 0.80. Visual and photographic observation of vapor condensation was also made through a clear cover on the system condenser. During the flight tests, the experiment hardware was exposed to gravitational acceleration ranging from near-zero to 1.8 g's.

Comments of the Space Shuttle crew indicate that the Launch Entry Suit (LES) may provide inadequate cooling before launch and after reentry. During these periods some crewmembers experienced thermal discomfort induced by localized cabin heating, middeck experiments, and crewmembers' body heat and humidity. The NASA Johnson Space Center(JSC) Crew and Thermal System Division (CTSD) executed a two phase study, analysis and testing, to investigate this problem. The analysis phase used a computer model of the LES to study the transient heat dissipation and temperature response under the various Space Shuttle flight cabin environments. After the completion of the analysis, the testing phase was conducted to collect the engineering data in order to validate the analysis results. Due to the constraint of the test facility, the test was conducted on the air cooled techniques only. This paper presents the analytical model, its solution and an evaluation and summary of the test results.

Space-faring crews must have safe breathing air throughout their missions to ensure adequate performance and good health. Toxicological assessment of air quality depends on the standards that define acceptable air quality, measurements of pollutant levels during the flight, and reports from the crew on their in-flight perceptions of air quality. Air samples from ISS flights 2A.2a, 2A.2b, 3A, and 4A were analyzed for trace pollutants. On average the air during each flight was safe for human respiration. However, there were reports from the crew that they experienced a headache when in certain areas, and strong odors were reported from specific locations of the ISS complex. Inspection of air samples in these locations suggested that several of the solvent-type pollutants (e.g. ethyl acetate, xylenes, and n-butanol) were present in concentrations that would cause a strong odor to be perceived by some individuals.