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NASA NTRS1991

Science requirements for a global change technology initiative architecture trade study

Science requirements for a Global Change Technology Initiative (GCTI) Architecture Trade Study were established by reviewing and synthesizing results from recent studies. A scientific rationale was adopted and used to identify a comprehensive set of measurables and their priorities. Spatial and temporal requirements for a number of measurement parameters were evaluated based on results from several working group studies. Science requirements were defined using these study results in conjunction with guidelines for investigating global changes over a time scale of decades to centuries. Requirements are given separately for global studies and regional process studies. For global studies, temporal requirements are for sampling every 1 to 12 hours for atmospheric and radiation parameters and 1 day or more for most Earth surface measurements. Therefore, the atmospheric measurables provide the most critical drivers for temporal sampling. Spatial sampling requirements vary from 1 km for land and ocean surface characteristics to 50 km for some atmospheric parameters. Thus, the land and ocean surface parameters have the more significant spatial variations and provide the most challenging spatial sampling requirements.

Suttles, John T.↗
NASA NTRS1991

Information data systems for a global change technology initiative architecture trade study

The Global Change Technology Initiative (GCTI) was established to develop technology which will enable use of satellite systems of Earth observations on a global scale, enable use of the observations to predictively model Earth's changes, and provide scientists, government, business, and industry with quick access to the resulting information. At LaRC, a GCTI Architecture Trade Study was undertaken to develop and evaluate the architectural implications to meet the requirements of the global change studies and the eventual implementation of a global change system. The output of the trade study are recommended technologies for the GCTI. That portion of the study concerned with the information data system is documented. The information data system for an earth global change modeling system can be very extensive and beyond affordability in terms of today's costs. Therefore, an incremental approach to gaining a system is most likely. An options approach to levels of capability versus needed technologies was developed. The primary drivers of the requirements for the information data system evaluation were the needed science products, the science measurements, the spacecraft orbits, the instruments configurations, and the spacecraft configurations and their attendant architectures. The science products requirements were not studied here; however, some consideration of the product needs were included in the evaluation results. The information data system technology items were identified from the viewpoint of the desirable overall information system characteristics.

Murray, Nicholas D.↗
NASA NTRS1991

Global change technology initiative architecture trade study plan

The overall objective of the trade study is to define the architectural mix of missions, spacecraft/platforms, and sensors to meet the science requirements of the Mission to Planet Earth/Global Change Technology Initiative (MPE/GCTI) beyond the early Earth Observing System (Eos) and Geosynchronous Earth Orbit (GEO) spacecraft missions. Within the overall objective, the study includes the following specific objectives: (1) Substantiate the selected mix of Low Earth Orbit (LEO), GEO, or intermediate orbit spacecraft/platforms; (2) Define the required number and size of spacecraft related to objective (1); (3) Define a generic sensor complement for the spacecraft/platforms; (4) Evaluate current spacecraft capabilities to meet the mission requirements and develop conceptual designs of spacecraft/platforms as required. (5) Identify advanced or new technology needed to most efficiently accomplish the MPE/GCTI Program.

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NASA NTRS1991

Kappa Group: The initial guess. A proposal in response to a commercial air transportation study

Kappa Aerospace presents their Aeroworld Aircraft, the Initial Guess (IG). This aircraft is designed to generate profit in the market which is currently controlled by the train and boat industry. The main priority of the design team was to develop an extremely efficient aircraft that could be sold at a reasonable price. The IG offers a quick and safe alternative to the existing means of transportation at a competitive price. The cruise velocity of 28 ft/sec. allows all flights to be between 20 and 45 minutes, which is a remarkable savings in time compared to travel by boat or train. The IG is propelled by a single Astro-05 engine with a Zinger 10-6 propeller. The Astro-05 is not an extremely powerful engine; however, it provides enough thrust to meet the design and safety requirements. The major advantage of the Astro-05 is that it is the most efficient engine available. The fuel efficiency of the Astro-05 is what puts the aircraft ahead of the competition. The money saved on an efficient engine can be passed on as lower ticket prices or increased revenue. The IG has a payload of 56 passengers and a wingspan of 7 ft. The 7 ft. wingspan allows the aircraft to fit into the gates of all of the cities that are targeted. Future endeavors of Kappa Aerospace will include fitting a stretch version of the IG with a larger propulsion system. This derivative aircraft will be able to carry more passengers and will be placed on the routes which have the greatest demand for travel. The fuselage and empennage are made of a wooden truss configuration, while the wing is made of a rib/spare configuration. The stress carrying elements are made of spruce, the nonstress carrying elements are made of balsa. The wing is removable for easy access into the fuselage. The easy access to the batteries will keep maintenance costs down.

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NASA NTRS1992

The NASA Langley laminar-flow-control experiment on a swept, supercritical airfoil: Evaluation of initial perforated configuration

The initial evaluation of a large-chord, swept, supercritical airfoil incorporating an active laminar-flow-control (LFC) suction system with a perforated upper surface is documented in a chronological manner, and the deficiencies in the suction capability of the perforated panels as designed are described. The experiment was conducted in the Langley 8-Foot Transonic Pressure Tunnel. Also included is an evaluation of the influence of the proximity of the tunnel liner to the upper surface of the airfoil pressure distribution.

Harris, Charles D.↗
NASA NTRS1991

Applications of the Strategic Defense Initiative's compact accelerators

The Strategic Defense Initiative's (SDI) investment in particle accelerator technology for its directed energy weapons program has produced breakthroughs in the size and power of new accelerators. These accelerators, in turn, have produced spinoffs in several areas: the radio frequency quadrupole linear accelerator (RFQ linac) was recently incorporated into the design of a cancer therapy unit at the Loma Linda University Medical Center, an SDI-sponsored compact induction linear accelerator may replace Cobalt-60 radiation and hazardous ethylene-oxide as a method for sterilizing medical products, and other SDIO-funded accelerators may be used to produce the radioactive isotopes oxygen-15, nitrogen-13, carbon-11, and fluorine-18 for positron emission tomography (PET). Other applications of these accelerators include bomb detection, non-destructive inspection, decomposing toxic substances in contaminated ground water, and eliminating nuclear waste.

Montanarelli, Nick↗
NASA NTRS1991

Automation and robotics for the Space Exploration Initiative: Results from Project Outreach

A total of 52 submissions were received in the Automation and Robotics (A&R) area during Project Outreach. About half of the submissions (24) contained concepts that were judged to have high utility for the Space Exploration Initiative (SEI) and were analyzed further by the robotics panel. These 24 submissions are analyzed here. Three types of robots were proposed in the high scoring submissions: structured task robots (STRs), teleoperated robots (TORs), and surface exploration robots. Several advanced TOR control interface technologies were proposed in the submissions. Many A&R concepts or potential standards were presented or alluded to by the submitters, but few specific technologies or systems were suggested.

Gonzales, D.↗
NASA NTRS1991

Human support issues and systems for the space exploration initiative: Results from Project Outreach

The analyses and evaluations of the Human Support panel are discussed. The Human Support panel is one of eight panels created by RAND to screen and analyze submissions to the Space Exploration Initiative (SEI) Outreach Program. Submissions to the Human Support panel were in the following areas: radiation protection; microgravity; life support systems; medical care; and human factors (behavior and performance).

Aroesty, J.↗
NASA NTRS1992

NASA/DOD Aerospace Knowledge Diffusion Research Project. Report 12: An initial investigation into the production and use of Scientific and Technical Information (STI) at five NASA centers: Results of a telephone survey

A study was conducted to provide NASA management with an 'initial' look at the production and use of scientific and technical information (STI) at five NASA centers (Ames, Goddard, Langley, Lewis, and Marshall). The 550 respondents who were interviewed by telephone held favorable views regarding the NASA STI system. About 65 percent of the respondents stated that it is either very or somewhat important for them to publish their work through the NASA STI system. About 10 percent of those respondents encountered problems using the NASA STI system services for publication. The most frequently reported problem was 'the process is too time consuming' (8.6 percent). Overall, those respondents using the NASA STI system to publish their work rated the system as excellent (24.6 percent) or good (37.6 percent). About 79 percent of the respondents stated that it is either very or somewhat important for them to use the NASA STI system to access information. The most frequently reported problems were 'the time and effort it takes to locate and obtain information through the system' (14.4 percent). Overall, about 83 percent of the respondents stated that the NASA STI system is important to performing their work. Overall, about 73 percent of the respondents stated that the NASA STI system meets their information needs.

Glassman, Nanci A.↗
NASA NTRS1992

The benchmark aeroelastic models program: Description and highlights of initial results

An experimental effort was implemented in aeroelasticity called the Benchmark Models Program. The primary purpose of this program is to provide the necessary data to evaluate computational fluid dynamic codes for aeroelastic analysis. It also focuses on increasing the understanding of the physics of unsteady flows and providing data for empirical design. An overview is given of this program and some results obtained in the initial tests are highlighted. The tests that were completed include measurement of unsteady pressures during flutter of a rigid wing with an NACA 0012 airfoil section and dynamic response measurements of a flexible rectangular wing with a thick circular arc airfoil undergoing shock boundary layer oscillations.

Bennett, Robert M.↗
NASA NTRS1991

The Space Exploration Initiative

The goals of the Space Exploration Initiative (SEI) and the content and current status of NASA activities and studies relevant to the SEI are briefly reviewed. The principal way points of the program are discussed with particular reference to lunar exploration, preparations for a Martian mission, habitation, and fuels. Attention is also given to the problem of enhancing energy delivery on earth, the use of asteroids as way points, and activities related to the human exploration of Mars.

Aldrich, Arnold D.↗
NASA NTRS1991

Space transportation options for the Space Exploration Initiative

The candidate architectures of space transportation vehicles designed for the Space Exploration Initiative are discussed together with the launch systems concepts. Special attention is given to the lunar mission and Mars mission scenarios and the launch- and transfer-vehicle options for Mars and moon missions.

Huber, William G.↗
NASA NTRS1991

Status of robotic mission studies for the Space Exploration Initiative - 1991

Results of studies of robotic missions to the moon and Mars planned under the U.S. Space Exploration Initiative are summarized. First, an overall strategy for small robotic missions to accomplish the information gathering required by human missions is reviewed, and the principal robotic mission requirements are discussed. The discussion covers the following studies: the Lunar Observer, the Mars Environmental Survey mission, Mars Sample Return missions using microtechnology, and payloads.

Bourke, Roger D.↗
NASA NTRS1992

From a lunar outpost to Mars - Science, policy and the U.S. Space Exploration Initiative

The technological developments required for the Space Exploration Initiative (SEI) objectives are discussed in terms of scientific investigation and present U.S. space policy. The results of the 90-Day Study are listed which include explicit suggestions for the successful exploration of the moon and Mars. The Outreach/Synthesis program is described which provides four methods for eliciting ideas, technologies, and research venues for lunar and Martian missions. The results of the studies include 5 scientific objectives such as the relationship between the sun, planetary atmospheres, and climate. The protection of human life from potential extraterrestrial hazards such as radiation is also found to be a key objective of SEI as are the theoretical and practical issues of scientific research.

Pilcher, Carl B.↗
NASA NTRS1991

ECLSS instrumentation technology development for the Space Exploration Initiative

A study of ECLSS instrumentation technologies and an evaluation of SEI ECLSS mission requirements have identified several areas where instrumentation enhancements are required. Attention is given to the ECLSS instrument database fields including development potential, accuracy, cycle time, reliability, resolution, and selectivity. An initial list of instrumentation technologies is recommended for further development to correct each of the deficiencies identified.

Diamant, Bryce L.↗
NASA NTRS1991

Analysis of an initial lunar outpost life support system preliminary design

A preliminary design of a life-support system (LSS) was developed as part of an ongoing comprehensive trade study of advanced processor technologies and system architectures for an initial lunar outpost. The design is based on a mission scenario requiring intermittent occupation of a lunar-surface habitat by a crew of four. It incorporates physiochemical process technologies that were considered for Space Station Freedom. A system-level simulation model of the design was developed to obtain steady-state material balances for each LSS processor. The mass-flow rate predictions were used to obtain estimates of the LSS mass, volume, and power consumption by means of processor-sizing correlations that were extrapolated from Space Station Freedom processor designs. The results were used to analyze the impacts of varying crew size, mission duration, processor-operation strategy, and crew-cabin loads on the LSS mass, average power consumption, volume, periodic resupply mass, and waste-accumulation rates. The merits of the design were quantified relative to an open-loop LSS, and the implications of this assessment for future LSS research and technology development were identified.

Ballin, Mark G.↗
NASA NTRS1992

Initial operation of the UTA shock tunnel

Initial experience in operating a small UTA (University of Texas at Arlington) shock tunnel at high Reynolds numbers for perfect gas simulation of hypersonic flow and boundary layer studies is described. Particular attention is given to tradeoffs between various constraints for achieving the test requirements, and methods for obtaining precise control of test conditions and protecting low-range pressure transducers from overpressure damage.

Lu, Frank K.↗
NASA NTRS1992

Constant reverse thrust activated reorientation of liquid hydrogen with Geyser initiation

A key objective of the cryogenic fluid management of the spacecraft propulsion system is to develop the technology necessary for acquisition or positioning of liquid outflow or vapor venting. Numerical simulation of positive liquid acquisition is attempted by introducing reverse gravity acceleration, resulting from the propulsive thrust of auxiliary engines, which exceeds critical value for the initiation of geyser. Based on the computer simulation of flowfields during the course of fluid reorientation, six dimensionless parameters resulted in this study. It shows that these parameters hold near-constant values through the entire ranges of liquid filled levels, from 30-80 percent, during the course of fluid reorientation.

Hung, R. J.↗