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Wet oxidation was used to oxidize a spacecraft model waste under different oxidation conditions. The variables studied were pressure, temperature, duration of oxidation, and the use of one homogeneous and three heterogeneous catalysts. Emphasis is placed on the final oxidation state of carbon and nitrogen since these are the two major components of the spacecraft model waste and two important plant nutrients.

Piloted, moving-base simulations have been performed in the evaluation of several VTOL control system concepts during landings on a destroyer in adverse weather conditions. All the systems incorporated attitude control augmentation; most systems incorporated various types of translational control augmentation implemented either through aircraft attitude or, more directly, through the propulsion system (thrust magnitude and deflection). Only one of the control systems failed to provide satisfactory handling qualities in calm seas. Acceptable handling qualities in sea state 6 seem to require a system with control augmentation in all translational degrees of freedom.

The first step in verifying the design of the rodent Research Animal Holding Facility (RAHF) as a barrier to environmental contaminants was successfully completed at NASA Ames Research Center (ARC) during a 12-day bio-compatibility test. Environmental contaminants considered were solid particulates, microorganisms, ammonia, and odor-producing organics. The 12-day test at ARC was conducted in August 1988, and was designed to verify that the rodent RAHF system would adequately support and maintain animal specimens during normal system operations. Additional objectives of this test were to demonstrate that: 1) typical particulate debris produced by the animal, i.e., feces and food bar crumbs, would be captured by the system; 2) microorganisms would be contained; and 3) the passage of odor-producing organics and ammonia generated by the animals was adequately controlled. In addition, the amount of carbon dioxide exhausted by the RAHF system was to be quantified.

The Spacelab Life Sciences 2 mission (SLS-2) is the second in a planned series of dedicated Life Sciences missions utilizing the European Space Agency-provided Spacelab module. The mission, tentatively scheduled for a mid-1992 launch, will comprise a total of eighteen experiments encompassing both human and animal research. Eight of the eighteen experiments will involve animal life sciences research and will be managed by the Space Life Sciences Payloads Office (SLSPO) at NASA's Ames Research Center (ARC). The ARC payload complement of eight experiments will include six which use rodents and two which use primates (squirrel monkeys). SLS-2 provides an opportunity for even more extensive investigations into the effects of weightlessness upon the anatomy and physiology of rodent and primate systems.

The evolutionary history of life on Earth has occurred under the omnipresent influence of a gravitational force. The exposure to the microgravity environment of space produces an array of biochemical and physiological changes in plants and animals. These changes extend from the cellular to the whole organism level. In order to manipulate gravity as an experimental variable and to separate the effects of weightlessness from the other variables in spaceflight, it is essential to provide a source of gravity in space. The scientific user community was consulted on the potential need and science requirements for a centrifuge to be designed for and flown on Space Station Freedom.

The Space Station Freedom will provide a wealth of new opportunities for life sciences research in the microgravity environment of Earth orbit. Such research will require the long-term housing of plant and animal subjects, as well as cell and tissue culture support systems. In addition to newly designed plant and animal vivaria for micro-g, housing for control subjects at one g and fractional g will be required to provide scientific controls, support gravity threshold studies, and perform experiments at Lunar and Mars gravity levels. A natural adjunct to a set of microgravity vivaria in space is, therefore, a centrifuge which could expose the same specimens to variable gravity levels. The larger the centrifuge, the more subjects that can be housed, the smaller the gravity gradient on the subjects, and the smaller the Coriolis effects. Early studies recommended a 4.0 meter diameter centrifuge, the largest that could be accommodated in a Shuttle launchable module.

An inventory was made of the quantities and types of wastes to be produced by typical missions proposed by NASA's Office of Space Science and Applications (OSSA) for the initial operational phase (IOC) of the Space Station. Of the 35 missions inventoried, 21 missions involve “payloads” (instrument packages) attached externally to the Space Station, 12 involve payloads that are located on “free-flying” platforms remote from the Station and 2 missions, (Life Sciences and Materials Sciences laboratories) comprise a complex series of experiments to be carried out inside the Station's pressurized volume. The study objective was to acquire the information needed to define preliminary OSSA waste management requirements for the Space Station and the National Space Transportation System. The study revealed that all missions combined will generate approximately 5350 kg (11800 lbs) of waste (solid, liquid and gas) every 90 days.

The facilities being planned for animal research on Space Station Freedom are considered in the context of the development of animal habitats from early ballistic and orbital flights to long-term missions aimed at more detailed scientific studies of the effects of space conditions on the vertebrate organism. Animal habitats are becoming more elaborate, requiring systems for environmental control, waste management, physiological monitoring, as well as ancillary facilities such as a 1-G control centrifuge and a glovebox. Habitats in use or to be used in various types of manned and unmanned spacecraft, and particularly those planned for Space Station Freedom, are described. The characteristics of the habitats are compared with each other and with current standards for animal holding facilities on the ground.

An integrated engineering breadboard subsystem for the recovery of potable water from untreated urine was designed, fabricated and tested. It was fabricated from commercially available components without emphasis on weight, volume and power requirement optimization. Optimizing these parameters would make this process competitive with other spacecraft water recovery systems. Unlike other phase change systems, this process is based on the catalytic oxidation at elevated temperatures of ammonia and volatile hydrocarbons to innocuous products; therefore, no urine pretreatment is required. The testing program consisted of parametric tests, one month of daily tests, and a continuous run of 165 hours. The recovered water is low in ammonia, hydrocarbons and conductivity and requires only adjustment of its pH to meet drinking water standards.

The effectiveness of an aerodynamic boattail on a tractor/trailer road vehicle was measured in the NASA Ames Research Center 80- by 120- Foot Wind Tunnel. Results are examined for the tractor/trailer with and without the drag reduction device. Pressure measurements and flow visualization show that the aerodynamic boattail traps a vortex or eddy in the corner formed between the device and the rear corner of the trailer. This recirculating flow turns the flow inward as it separates from the edges of the base of the trailer. This modified flow behavior increases the pressure acting over the base area of the truck, thereby reducing the net aerodynamic drag of the vehicle. Drag measurements and pressure distributions in the region of the boattail device are presented for selected configurations. The optimum configuration reduces the overall drag of the tractor/trailer combination by about 10 % at a zero yaw angle.