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From November 2010 until May of 2011, NASA's Icing Remote Sensing System was positioned at Platteville, Colorado between the National Science Foundation's S-Pol radar and Colorado State University's CHILL radar (collectively known as FRONT, or ‘Front Range Observational Network Testbed’). This location was also underneath the flight-path of aircraft arriving and departing from Denver's International Airport, which allowed for comparison to pilot reports of in-flight icing. This work outlines how the NASA Icing Remote Sensing System's derived liquid water content and in-flight icing hazard profiles can be used to provide in-flight icing verification and validation during icing and non-icing scenarios with the purpose of comparing these times to profiles of polarized moment data from the two nearby research radars.

Ice accretions that have formed inside gas turbine engines as a result of flight in clouds of high concentrations of ice crystals in the atmosphere have recently been identified as an aviation safety hazard. NASA's Aviation Safety Program (AvSP) has made plans to conduct research in this area to address the hazard. This paper gives an overview of NASA's engine ice-crystal icing research project plans. Included are the rationale, approach, and details of various aspects of NASA's research.

Operational issues encountered by Apollo astronauts relating to lunar dust were catalogued, including material abrasion that resulted in scratches and wear on spacesuit components, ultimately impacting visibility, joint mobility and pressure retention. Standard methods are being developed to measure abrasive wear on candidate construction materials to be used for spacesuits, spacecraft, and robotics. Calibration tests were conducted using a standard diamond stylus scratch tip on the common spacecraft structure aluminum, Al 6061-T6. Custom tips were fabricated from terrestrial counterparts of lunar minerals for scratching Al 6061-T6 and comparing to standard diamond scratches. Considerations are offered for how to apply standards when selecting materials and developing dust mitigation strategies for lunar architecture elements.

A fire in spacecraft or habitat supporting NASA's Exploration mission could jeopardize the system, mission, and/or crew. Given adequate measures for fire prevention, the hazard from a fire can be significantly reduced if fire detection is rapid and occurs in the early stages of fire development. The simultaneous detection of both particulate and gaseous products has been proven to rapidly detect fires and accurately distinguish between real fires and nuisance sources. This paper describes the development status of gaseous and particulate sensor elements, integrated sensor systems, and system testing. It is concluded that while development is still necessary, the fundamental approach of smart, miniaturized, multisensor technology has the potential to significantly improve the safety of NASA space exploration systems.

Two separate experimental rigs used in tests on NASA and Zero-G Corporation aircrafts flying low-gravity trajectories, and in the NASA 2.2 Second Drop Tower have been developed to test the functioning of the Flexible Membrane Commode (FMC) concept under reduced gravity conditions. The first rig incorporates the flexible, optically opaque membrane bag and the second rig incorporates a transparent chamber with a funnel assembly for evacuation that approximates the size of the membrane bag. Different waste dispensers have been used including a caulking gun and flexible hose assembly, and an injection syringe. Waste separation mechanisms include a pair of wire cutters, an iris mechanism, as well as discrete slug injection. The experimental work is described in a companion paper. This paper focuses on the obtained results and analysis of the data.

The thick oxide layer of silicon-on-insulator (SOI) devices significantly reduces the junction leakage current at elevated temperatures compared to similar Si devices, resulting in an elevated maximum operating temperature. The maximum operating temperature, specified by manufacturers, of commercial SOI devices/circuits with conventional packaging is usually 225°C. It is important to understand the performance and de-ratings of these SOI circuits at temperatures above 225°C without the temperature limit imposed by commercial packaging technology. This work tested a low frequency square-wave oscillator based on an SOI 555 Timer with a special high temperature ceramic packaging technology from room temperature to 375°C. The timer die was attached to a 96% aluminum oxide substrate with high temperature durable gold (Au) thick-film metallization, and interconnected with Au wires.

Spacecraft radiators reject heat to their surroundings. Radiators can be deployable or mounted on the body of the spacecraft. NASA's Crew Exploration Vehicle is to use body mounted radiators. Coatings play an important role in heat rejection. The coatings provide the radiator surface with the desired optical properties of low solar absorptance and high infrared emittance. These specialized surfaces are applied to the radiator panel in a number of ways, including conventional spraying, plasma spraying, or as an appliqué. Not specifically designed for a weathering environment, little is known about the durability of conventional paints, coatings, and appliqués upon exposure to weathering and subsequent exposure to solar wind and ultraviolet radiation exposure. In addition to maintaining their desired optical properties, the coatings must also continue to adhere to the underlying radiator panel.

Smoke transport and detection were modeled numerically in the ISS Destiny module using the NIST, Fire Dynamics Simulator code. The airflows in Destiny were modeled using the existing flow conditions and the module geometry included obstructions that simulate the currently installed hardware on orbit. The smoke source was modeled as a 0.152 by 0.152 m region that emitted smoke particulate ranging from 1.46 to 8.47 mg/s. In the module domain, the smoke source was placed in the center of each Destiny rack location and the model was run to determine the time required for the two smoke detectors to alarm. Overall the detection times were dominated by the circumferential flow, the axial flow from the intermodule ventilation and the smoke source strength.

Using a new fiber electrode technology, currently developed and produced by Bekaert Corporation (Bekaert), Electro Energy, Inc., (EEI) Mobile Energy Products Group (formerly, Eagle-Picher Technologies, LLC, Power Systems Department) in Colorado Springs, CO has demonstrated that it is feasible to manufacture flight weight nickel hydrogen cells having about twice the specific energy (80 vs. 40 watt-hr./kg) as state-of-the-art nickel hydrogen cells that are currently flown on geosynchronous communications satellites. Although lithium-ion battery technology has made large in-roads to replace the nickel alkaline technology (nickel-cadmium, nickel-metal hydride), the technology offered here competes with lithium-ion weight and offers alternatives not present in the lithium-ion chemistry such as: ability to undergo a continuous overcharge, reversal on discharge, and sustain rate capability sufficient to start automotive and aircraft engines at subzero temperatures.

The problem of determining equilibrium temperatures for re-radiating surfaces in space vacuum was analyzed and the resulting mathematical relationships were incorporated in a code to determine space sink temperatures in the solar system. A brief treatment of planetary atmospheres is also included. Temperature values obtained with the code are in good agreement with available spacecraft telemetry and meteorological measurements for Venus and Earth. The code has been used in the design of space power system radiators for future interplanetary missions.

NASA and the FAA are funding the development of ground-based remote sensing systems specifically designed to detect and quantify the icing environment aloft. The goal of the NASA activity is to develop a relatively low cost stand-alone system that can provide practical icing information to the flight community. The goal of the FAA activity is to develop more advanced systems that can identify supercooled large drop (SLD) as well as general icing conditions and be integrated into the existing weather information infrastructure. Both activities utilize combinations of sensing technologies including radar, radiometry, and lidar, along with Internet-available external information such as numerical weather model output where it is found to be useful. In all cases the measured data of environment parameters will need to be converted into a measure of icing hazard before it will be of value to the flying community.

To support NASA's goal to improve aviation safety, the Aircraft Icing Project of the Aviation Safety Program has developed a number of education and training aids for pilots and operators on the hazards of atmospheric icing. A review of aircraft incident and accident investigations has revealed that flight crews have not always understood the effects of ice contamination on their aircraft. To increase this awareness, NASA has partnered with regulatory agencies and pilot trade organizations to assure relevant and practical materials that are focused toward the intended pilot audience. A number of new instructional design approaches and media delivery methods have been introduced to increase the effectiveness of the training materials by enhancing the learning experience, expanding user interactivity and participation, and, hopefully, increasing learner retention rates.

Development of a high specific energy battery is one of the objectives of the lightweight nickel-hydrogen (Ni-H2) program at the NASA Glenn Research Center. The approach has been to improve the nickel electrode by continuing combined in-house and contract efforts to develop a lighter weight electrode for the nickel-hydrogen cell. Small fiber diameter nickel plaques are used as conductive supports for the nickel hydroxide active material. These plaques are commercial products and have an advantage of increased surface area available for the deposition of active material. Initial tests include activation and capacity measurements at five different discharge levels, C/2, 1.0C, 1.37C, 2.0C, and 2.74C. The electrodes are life cycle tested using a half-cell configuration at 40 and 80% depths-of-discharge (DOD) in a low-Earth-orbit regime. The electrodes that pass the initial tests are life cycle-tested in a boilerplate nickel-hydrogen cell before flightweight designs are built and tested.

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. This information can lead to modifications and correlations to standard material-assessment tests for prediction of fire resistance in space. 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.