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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.

Takeoff predictions for powered lift short takeoff (STO) aircraft have been added to NASA AMES Research Center's aircraft synthesis (ACSYNT) code. The new computer code predicts the aircraft engine and nozzle settings required to achieve the minimum takeoff roll. As a test case, it predicted takeoff ground rolls and nozzle settings for the YAV-8B Harrier that were close to the actual values. Analysis of takeoff performance for an ejector-augmentor design and a vectoring-nozzle design indicated that ground roll can be decreased, for either configuration, by horizontally moving the rear thrust vector closer to the center of gravity, by increasing the vertical position of the ram drag-vector, or by moving the rear thrust vector farther below the center of gravity.

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.

Using a generalized simulation model developed for piloted evaluations of short take-off/vertical landing aircraft, an initial fixed-base simulation of a mixed-flow, remote-lift configuration has been completed. Objectives of the simulation were to evaluate the integration of the aircraft's flight and propulsion controls to achieve good flying qualities throughout the low-speed flight envelope; to determine control power used during transition, hover, and vertical landing; and to evaluate the transition flight envelope considering the influence of thrust deflection of the remote-lift component. Pilots’ evaluations indicated that Level 1 flying qualities could be achieved for deceleration to hover in instrument conditions, for airfield landings, and for recovery to a small ship when attitude and velocity stabilization and command augmentation control modes were provided.

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.

Ames Research Center is developing the technology for turbine-powered jet engine simulators so that airframe/propulsion system interactions on V/STOL fighter aircraft and other highly integrated configurations can be studied. This paper describes the status of the compact multimission aircraft propulsion simulator (CMAPS) technology. Three CMAPS units have accumulated a total of 340 hr during approximately 1-1/2 yr of static and wind-tunnel testing. A wind-tunnel test of a twin-engine CMAPS-equipped close-coupled canard-wing V/STOL model configuration with nonaxisymmetric nozzles was recently completed. During this test approximately 140 total hours were logged on two CMAPS units, indicating that the rotating machinery is reliable and that the CMAPS and associated control system provide a usable test tool. However, additional development is required to correct a drive manifold O-ring problem that limits the engine-pressure-ratio (EPR) to approximately 3.5.

Optimal turning climb-out and descent flight-paths from and to runway headings are derived to provide the missing elements of a complete flight-path optimization for minimum fuel consumption. The paths are derived by generating a field of extremals, using the necessary conditions of optimal control. Results show that the speed profiles for straight and turning flight are essentially identical, except for the final horizontal accelerating or decelerating turn. The optimal turns, which require no abrupt maneuvers, could easily be integrated with present climb-cruise-descent fuel-optimization algorithms.

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.

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 Life Sciences Glovebox will provide the bioisolated environment to support on-orbit operations involving non-human live specimens and samples for human life sciences experiments. It will be part of the Centrifuge Facility, in which animal and plant specimens are housed in bioisolated Habitat modules and transported to the Glovebox as part of the experiment protocols supported by the crew. At the Glovebox, up to two crew members and two Habitat modules must be accommodated to provide flexibility and support optimal operations. This paper will present several innovative design concepts that attempt to satisfy the basic Glovebox requirements. These concepts were evaluated for ergonomics and ease of operations using computer modeling and full-scale mockups. The more promising ideas were presented to scientists and astronauts for their evaluation. Their comments, and the results from other evaluations are presented.

This paper reports the results of a project supported by the National Aeronautics and Space Administration, Office of Aeronautics and Space Technology (NASA-OAST) under the Advanced Life Support Development Program. It is an initial attempt to integrate artificial intelligence techniques (via expert systems) with conventional quantitative modeling tools for advanced physical-chemical life support systems. The addition of artificial intelligence techniques will assist the designer in the definition and simulation of loosely/well-defined life support processes/problems as well as assist in the capture of design knowledge, both quantitative and qualitative. Expert system and conventional modeling tools are integrated to provide a design workstation that assists the engineer/scientist in creating, evaluating, documenting and optimizing physical-chemical life support systems for short-term and extended duration missions.

Several studies performed in support of the Space Exploration Initiative have identified the need for development or improvement of new or existing regenerative life support process technologies. In part, the need to develop such technologies is dependent on the quantities of consumables that are required by the mission and hence on mission design. Trade studies will be needed to determine appropriate life support system designs that provide consumables to the crew and support systems and dispose of waste materials that are generated. These studies will require quantitative estimates of consumables and waste stream disposal requirements that support a given mission scenario. The NASA Exploration Programs Office (ExPO) is attempting to define the details and logistics of a design reference mission for the first human return to the Moon. The mission is referred to as the First Lunar Outpost.

A new flight research vehicle, the Rotorcraft-Aircrew Systems Concepts Airborne Laboratory (RASCAL), is being developed by the U.S. Army and NASA at Ames Research Center. The requirements for this new facility stem from a perception of rotorcraft system technology requirements for the next decade together with operational experience with the Boeing Vertol CH-47B research helicopter that was operated as an in-flight simulator at Ames during the past 10 years. Accordingly, both the principal design features of the CH-47B variable-stability system and the flight-control and cockpit-display programs that were conducted using this aircraft at Ames are reviewed. Another U.S. Army helicopter, a Sikorsky UH-60A Black Hawk, has been selected as the baseline vehicle for the RASCAL. The research programs that influence the design of the RASCAL are summarized, and the resultant requirements for the RASCAL research system are described.