08 AIRCRAFT STABILITY AND CONTROL Includes aircraft handling qualities; piloting; flight controls; and autopilots. For related information see also 05 Aircraft Design, Testing and Performance. N91-10077 National Aerospace Lab., Tokyo (Japan). STOL Aircraft Project Group. THE FULL-BODY GROUND VIBRATION TESTS USING THE LOW-NOISE STOL TEST PLANE [TEISOUON SUTORU JIKKENKI NO ZENKI CHIJOU SHINDOU SHIKEN (SHINDOU DETA KANRISHISUTEMU)] Oct. 1987 30 p In JAPANESE (NAL-TM-576; ISSN-0452-2982; JTN-90-80005) Avail: NTIS HC/MF A03 Experimental oscillation test equipment of NAL (National Aerospace Laboratory) was used for the whole-craft terrestrial oscillation test of the low-noise experimental STOL craft. The main components of the equipment include a system for analyzing multi-point applied oscillation, an oscillation data control system and a model analyzer. An oscillation test of the actual craft will need the exchange between several large scale or personal computers of the data obtained in the oscillation analyses and the experimental oscillation test. The oscillation control system assures the interexchange of data between different data types and the conversion of information media. This report presents the configuration and funtions of the system for analyzing multi-point applied oscillation and describes the role of the oscillation data control system in the whole-craft oscillation test. The report also described the developed software and its actual applications. NASDA N91-10078*# National Aeronautics and Space Administration. DETERMINATION OF THE PRESSURE DRAG OF AIRFOILS BY (NASA-TM-102722; NAS 1.15:102722) Avail: NTIS HC/MF_A03 CSCL 01C A study was conducted of the causes of pressure drag of subsonic airfoils. In a previous paper by the author, the pressure drag is obtained by calculating the total drag from the momentum defect in the boundary layer at the trailing edge and subtracting the friction drag obtained from integration of surface friction along the chord. Herein, the pressure drag is obtained by integrating the streamwise components of surface pressure around the airfoil. Studies were made to verify the accuracy of the integration procedure. The values of pressure drag were much smaller than those obtained by the previous method. This lack of agreement is attributed to the difficulty of calculating boundary layer conditions in the vicinity of the trailing edge and to the extreme sensitivity of the circulation and lift to the trailing edge conditions. The results of these studies are compared with those of previous investigations. Author 09 RESEARCH AND SUPPORT FACILITIES (AIR) Includes airports, hangars and runways; aircraft repair and overhaul facilities; wind tunnels; shock tubes; and aircraft engine test stands. For related information see also 14 Ground Support Systems and Facilities (Space). N91-10080 National Aerospace Lab., Tokyo (Japan). Hiroyasu Kawahara, Masanori Okabe, Akira Watanabe, Toshio The National Aerospace Laboratory (NAL) has fixed the simulation control unit, the visual simulation unit and the motion simulation unit over a period of three years and four months since 1980. The present report explains the configuration, function, and capacity of the motion simulation unit. For multi-freedom-degree motion simulation units, various kinds of systems have been developed and are in use such as Zimbal method, joint-motion suspension method, joint-motion support method, and special drive method. The joint-motion six-freedom-degree support method was adopted. NASDA N91-10081 National Aerospace Lab., Tokyo (Japan). Masamitsu Suzuki, Nobuhiro Toda, Yukio Komatsu, and Toshio As a part of the improvement of the two meter times two meter Transonic Wind Tunnel, the National Aerospace Laboratory decide to modify the main air blower unit, which is located at the center of this tunnel. Repair of this unit was completed at the end of May, 1987. The improvement plan and modified unit configulation are described. NASDA N91-10082 National Aerospace Lab., Tokyo (Japan). The visual simulation unit with CGI (Computer Generated Imagery) enables a simulation of natural conditions by obtaining a wide view thanks to an increase in the number of display channels which catch sight of a wider range of flight. It is characterized by the ability to indicate an object in motion within sight as well as to add, delete, change, or otherwise revise the configuration of the ground or buildings generated as a simulated vision. The configuration, function, and capacity of the visual simulation unit with the CGI was introduced in consideration of the necessity to cope with a simulation test intended for the research and development of a new aircraft model including STOL at the National Aerospace Laboratory (NAL). Attention was paid in the designing of the unit to the ease of preparation of a three-dimensional visual model, the ability to simulate a daytime sight in color and nighttime lights of various kinds, the ability to easily simulate natural conditions and the ease of maintenance. NASDA (NASA-CR-186958; NAS 1.26:186958) Avail: NTIS HC/MF A03 CSCL 14B The flow in the transonic test facility was investigated using the three dimensional computational fluid dynamics techniques. The application of the full Navier-Stokes three dimensional code to the flow qualities in the contraction section of transonic wind tunnel is discussed. Initially, two dimensional solutions indicated the possibility for large secondary flow to exist as a result of the asymmetries involved in the contraction section as it is constructed. The results of a full three dimensional solution indicate that only minor pressure variations actually occur in the contraction section within any given cross flow plane. Further analysis of the three dimensional solution indicated that these slight lateral pressure gradients lead to negligible secondary flows, except within a small region in the corners within the boundary layer. On the basis of present solution, it would not be expected that any flow asymmetries and/or secondary flow present within contraction section are associated with the methods by which the contraction is implemented in its present configuration. Author N91-10084# Federal Aviation Administration, Atlantic City, NJ. The results of the Federal Aviation Administration (FAA) Air Traffic Operational Evaluation of Automated Surface Observing System (ASOS) at the Tulsa International Airport, Oklahoma are detailed. The evaluation was conducted in order to obtain operational air traffic controller reaction to the AAI Corporation preproduction ASOS. The evaluation resulted in numerous recommendations to improve the ASOS prior to production. THE DESIGN AND FABRICATION OF THE CENTAUR NEUTRAL BUOYANCY TRAINER AND RELATED HARDWARE Final Report Alan S. Ware and Michael Hollingsworth 5 Apr. 1986 74 p (Contract NAS9-17325) (NASA-CR-171944; NAS 1.26:171944; H-86-04) Avail: NTIS HC/MF A04 CSCL 14B Two full scale mockups of the Centaur upper stage were designed, fabricated and delivered to NASA. One was the Centaur Weightless Environment Training Facility (WETF) trainer and the other was the Centaur 1-G mockup. The Centaur upper stage booster is designed to carry the spacecraft Galileo to Jupiter, and the spacecraft Ulysses to an orbit around the Sun after launch from the Space Shuttle. The flight vehicle has several Extravehicular Activity (EVA) contingency tasks that require crew training. This need for crew training generated the requirement for the Centaur WETF crew trainer, which is high fidelity in areas of expected crew interface. During the production of the Centaur WETF crew trainer, the need for a jumper cable from Centaur to the Orbiter was identified. This EVA contingency task would be the installation of a cable from the Orbiter cargo bay sill to various command data boxes on Centaur to allow crew control deployment should a failure occur. This task required the upgrading of volumetric boxes on the trainer to a high fidelity configuration including electrical connector installation and cable routing. Author N91-10086# Institut Franco-Allemand de Recherches, Saint-Louis (France). THE ISL HYPERSONIC SHOCK TUNNEL AND ITS G. Smeets 1 Jun. 1989 22 p (ISL-CO-213/89; ETN-90-97572) Avail: NTIS HC/MF A03 Th ISL hypersonic shock tunnel is described and the characteristics of hypersonic flows which can be produced in the shock tunnel are given. The five essential measuring techniques developed or collected during the last three decades when operating the tunnel, are presented: differential interferometry for flow vizualization and/or quantitative flow density measurements; laser differential interferometry for precise measurements of optical paths in a low density gas medium; heat flux measurements with thin film resistance thermometers; laser Doppler velocimetry; and the measurement of aerodynamic forces and moments in milliseconds. ESA (NAL-TR-1054; ISSN-0389-4010) Avail: NTIS HC/MF A03 A low turbulence calibration wind tunnel for laser velocimeters was constructed at NAL. Detailed flow quality measurements in this facility were successively achieved to obtain a better understanding of the characteristics of facility disturbances and identification of their sources, using two hot-wire anemometers, a microphone and an accelerometer. Experimental results show that overall residual turbulence levels in free stream are 0.04 and 0.06 percent at fan speeds of 600 RPM and 1200 RPM, respectively. Extensive analyses of turbulence fluctuations show that the free stream velocity is unexpectedly contaminated by acoustic disturbances, which are regarded as non-vortical fluctuations generated by fan blades and vibratory resonance of a portion of the wind tunnel. Such pressure disturbances acoustically propagate into the flow direction. Cross correlation measurements between two distant anemometers indicate that the contamination level reaches 70 percent in the overall axial fluctuation energy at 600 RPM. It is estimated that the vortical turbulence level is about 0.022 percent at this speed. Author N91-10089# Joint Publications Research Service, Arlington, VA. JPRS REPORT: SCIENCE AND TECHNOLOGY. USSR: SPACE 15 Mar. 1990 72 p Transl. into ENGLISH of various Russian documents (JPRS-USP-90-001) Avail: NTIS HC/MF A04 A collection of short news articles, many of which appeared in U.S.S.R. newspapers, and abstracts of scientific articles is presented. Topics covered include manned space mission highlights, space science research, interplanetary sciences, life sciences, space engineering, space applications, and space policy and administration. Author N91-10090# Joint Publications Research Service, Arlington, VA. JPRS REPORT: SCIENCE AND TECHNOLOGY. USSR: SPACE 15 May 1990 65 p Transl. into ENGLISH from various Russian articles (JPRS-USP-90-002) Avail: NTIS HC/MF A04 Abstracts of Soviet literature in various areas of the space sciences are compiled. The following subject areas are covered: manned missions; space sciences; interplanetary sciences; space engineering; space applications; and space policy administration. N91-10091# and M.G. Messerschmitt-Boelkow-Blohm/Entwicklungspring Nord, Bremen (Germany, F.R.). Dienstleistungsbereich. H. J. C. Koopmann and Mike C. Attwood 1990 9 p In order to logistically support the systems included in the Columbus program, logistic support concepts and facilities are developed. The logistics support functions for the Columbus operational phase includes the identification of major facility requirements and recommendations for support of the implementation planning. These tasks have to be complemented by the definition and implementation of a logistics support system and its related facilities and proceedings. Emphasis is given to the logistics functions which drive facility requirements, on general considerations for a long term support program, e.g., centralization aspects, and on the intended implementation approach. ESA N91-10418# Imperial Coll. of Science and Technology, London (England). Space and Atmospheric Physics Group. MULTISPACECRAFT MEASUREMENT AT VARYING SCALELENGTHS: THE CLUSTER/REGATTA OPPORTUNITY D. J. Southwood In ESA, Space Plasma Physics Investigation by Cluster and Regatta May 1990 p 1-5 (For primary document see N91-10417 01-46) Copyright Avail: NTIS HC/MF A08; EPD, ESTEC, Noordwijk, Netherlands HC 40 Dutch guilders 13 ASTRODYNAMICS Includes powered and free-flight trajectories; and orbital and launching dynamics. N91-10092*# National Aeronautics and Space Administration. Long-term orbital lifetime predictions are analyzed. Predictions were made for three satellites: the Solar Max Mission (SMM), the Long Duration Exposure Facility (LDEF), and the Pegasus Boiler Plate (BP). A technique is discussed for determining an appropriate ballistic coefficient to use in the lifetime prediction. The orbital decay rate should be monitored regularly. Ballistic coefficient updates should be done whenever there is a significant change in the actual decay rate or in the solar activity prediction. Author N91-10420# Imperial Coll. of Science and Technology, London M. W. Dunlop In ESA, Space Plasma Physics Investigation by Cluster and Regatta May 1990 p 17-22 (For primary document see N91-10417 01-46) Copyright Avail: NTIS HC/MF A08; EPD, ESTEC, Noordwijk, Netherlands HC 40 Dutch guilders 14 GROUND SUPPORT SYSTEMS AND FACILITIES (SPACE) Includes launch complexes, research and production facilities; ground support equipment, e.g., mobile transporters; and simulators. For related information see also 09 Research and Support Facilities (Air). N91-10093# National Oceanic and Atmospheric Administration, EDUCATOR'S GUIDE FOR BUILDING AND OPERATING R. Joe Summers (Chambersburg Area Senior High School, PA.) A great deal of meteorological and weather information is transmitted from satellites via direct readout to ground stations where it can be displayed and analyzed. This publication is designed to provide teachers with the basic information needed to operate a direct readout ground station so that they can introduce students to this new technology. With a direct readout ground station, every classroom can have access to millions of dollars of high tech equipment every day. Author N91-10094# Department of Energy, Washington, DC. Ronald S. Hawke, inventor (to DOE) (Lawrence Livermore National (DE90-014573; US-Patent-Appl-SN-341019; Patents-US-A7341019) Avail: NTIS HC/MF A03 An electromagnetic railgun accelerator system for accelerating projectiles by a plasma arc, introduces a breakdown inhibiting gas into the railgun chamber behind the accelerating projectile. The breakdown inhibiting gas, which absorbs electrons, is a halide or a halide compound such as fluorine or SF6. The gas is introduced between the railgun rails after the projectile has passed through inlets in the rails or the projectile; by coating the rails or the projectile with a material which releases the gas after the projectile passes over it; by fabricating the rails or the projectile or insulators out of a material which releases the gas into the portions of the chamber through which the projectile has traveled. The projectile may have a cavity at its rear to control the release of ablation DOE products. 10 P DOE N91-10096# Lawrence Livermore National Lab., CA. (DE90-015612; UCRL-102468; CONF-900756-26) Avail: NTIS HC/MF A02 The Fabry-Perot (F-P) velocimeter is our main diagnostic tool N91-10097# Bertin et Cie., Plaisir (France). C. Fumoux and G. Marquette 1990 5 p Presented at Internoise 1990, Goteberg, Sweden, 13-18 Aug. 1990 Sponsored by CNES (ETN-90-97584) Avail: NTIS HC/MF A01 A satellite placed under the cap of a space launcher is submitted to severe vibro-acoustic conditions especially during lift off and transonic phases. This high acoustic level field, which can be damaging for the satellite, is mainly nonstationary. Thus, caution must be taken about results produced by classical Fourier analysis, since they rely on strong stationary hypotheses. To characterize in an appropriate way nonstationary data, time frequency was analyzed by means of wavelet transform. Conceptually, the wavelet transform is similar to a Fourier transform, as there is convolution between the signal and an analyzing window, but it differs in that this window is frequency dependent, leading to a constant accuracy for all frequencies. In addition, the chosen wavelet, Morlet's wavelet, permits a direct reconstruction of the original time signature. This method was successfully applied to the analysis of the Ariane 4 launcher vibro-acoustic behavior. This study was based on real data, signals of transducers located at different places on the launcher and its proximity. Results show the interest of this technique for shock and transient analysis, nonstationarities, identification, and localization in the time/frequency plane. ESA The dynamics of the motion of the Small Expendable Deployer System (SEDS) is studied by using a simplified model in which no external forces (except the gravity gradient field) are applied on the tethered body and the tether is assumed massless. The dynamics of SEDS operation is modeled as a sequence of two phases: the deployment phase and the swing phase. For the first one the velocity dependent forces are found to force the tether forward from the local vertical. When the deployment ends, Coriolis effects vanish and the swing phase begins, which is characterized by a wide free libration. The time duration as well as velocity, acceleration and tension of the tethered body are estimated for both deployment and swing phases. Author N91-10099# National Aerospace Lab., Tokyo (Japan). Masakatsu Minegishi, Masaaki Sano, Keiji Komatsu, Toshiyuki 156 p A 1/5 scale replica model of the H-2 launch vehicle was constructed and tested for study of vehicle dynamics. This model was designed to duplicate, in miniature, as many of the full scale structural elements as was economically and technically feasible. A series of vibration tests, from the moving launcher phase to the second-state burn-out phase, were carried out, and resonant frequencies, mode shapes, and modal dampings were measured for each case. The test data verified the mathematical modeling techniques used for predicting the vibration characteristics of the various configurations of the H-2 launch vehicle. Author NATIONAL SPACE TRANSPORTATION SYSTEM REFERENCE. (NASA-TM-89785; NAS 1.15:89785) Avail: NTIS HC/MF A07 CSCL 22B An overview of the Space Transportation System is presented in which aspects of the program operations are discussed. The various mission preparation and prelaunch operations are described including astronaut selection and training, Space Shuttle processing, Space Shuttle integration and rollout, Complex 39 launch pad facilities, and Space Shuttle cargo processing. Also, launch and flight operations and space tracking and data acquisition are described along with the mission control and payload operations control center. In addition, landing, postlanding, and solid rocket booster retrieval operations are summarized. Space Shuttle program management is described and Space Shuttle mission summaries and chronologies are presented. A glossary of acronyms and abbreviations are provided. M.G. 18 SPACECRAFT DESIGN, TESTING AND PERFORMANCE Includes satellites; space platforms; space stations; spacecraft systems and components such as thermal and environmental controls; and attitude controls. For life support systems see 54 Man/System Technology and Life Support. For related information see also 05 Aircraft Design, Testing and Performance, 39 Structural Mechanics, and 16 Space Transportation. N91-10101*# Joint Oceanographic Inst., Inc., Washington, DC. THE SCIENTIFIC CASE FOR MAGNETIC FIELD SATELLITES Final Report George E. Backus, ed., Edward R. Benton, Christopher G. A. Harrison, and James R. Heirtzler (Woods Hole Oceanographic Inst., MA.) Sep. 1987 18 p (Grant NAGw-856) (NASA-CR-186532; NAS 1.26:186532) Avail: NTIS HC/MF_A03 CSCL 22B To make full use of modern magnetic data and the paleomagnetic record, we must greatly improve our understanding of how the geodynamo system works. It is clearly nonlinear, probably chaotic, and its dimensionless parameters cannot yet be reproduced on a laboratory scale. It is accessible only to theory and to measurements made at and above the earth's surface. These measurements include essentially all geophysical types. Gravity and seismology give evidence for undulations in the core-mantle boundary (CMB) and for temperature variations in the lower mantle which can affect core convection and hence the dynamo. VLBI measurements of the variations in the Chandler wobble and length of day are affected by, among other things, the electromagnetic and mechanical transfer of angular momentum across the CMB. Finally, measurements of the vector magnetic field, its intensity, or its direction, give the most direct access to the core dynamo and the electrical conductivity of the lower mantle. The 120 gauss coefficients of degrees up to 10 probably come from the core, with only modest interference by mantle conductivity and crustal magnetization. By contrast, only three angular accelerations enter the problem of angular momentum transfer across the CMB. Satellite measurements of the vector magnetic field are uniquely able to provide the spatial coverage required for extrapolation to the CMB, and to isolate and measure certain magnetic signals which to the student of the geodynamo represent noise, but which are of great interest elsewhere in geophysics. Here, these claims are justified and the mission parameters likely to be scientifically most useful for observing the geodynamo system are described. Author (NASA-CR-185614; NAS 1.26:185614; CSDL-T-1053) Avail: NTIS HC/MF A08 CSCL 22B Future missions to Mars may require pin-point landing precision, possibly on the order of tens of meters. The ability to reach a target while meeting a dynamic pressure constraint to ensure safe parachute deployment is complicated at Mars by low atmospheric density, high atmospheric uncertainty, and the desire to employ only bank angle control. The vehicle aerodynamic performance requirements and guidance necessary for 0.5 to 1.5 lift drag ratio vehicle to maximize the achievable footprint while meeting the constraints are examined. A parametric study of the various factors related to entry vehicle performance in the Mars environment is undertaken to develop general vehicle aerodynamic design requirements. The combination of low lift drag ratio and low atmospheric density at Mars result in a large phugoid motion involving the dynamic pressure which complicates trajectory control. Vehicle ballistic coefficient is demonstrated to be the predominant characteristic affecting final dynamic pressure. Additionally, a speed brake is shown to be ineffective at reducing the final dynamic pressure. An adaptive precision entry atmospheric guidance scheme is presented. The guidance uses a numeric predictor-corrector algorithm to control downrange, an azimuth controller to govern crossrange, and analytic control law to reduce the final dynamic pressure. Guidance performance is tested against a variety of dispersions, and the results from selected tests are presented. Precision entry using bank angle control only is demonstrated to be feasible at Mars. Author N91-10103*# National Aeronautics and Space Administration. Marshall Space Flight Center, Huntsville, AL. SPACE STATION FREEDOM ENVIRONMENTAL CONTROL J. L. Perry Washington Oct. 1990 30 p Space Station Freedom environmental control and life support system testing has been conducted at Marshall Space Flight Center since 1986. The phase 3 simplified integrated test (SIT) conducted from July 30, 1989, through August 11, 1989, tested an integrated air revitalization system. During this test, the trace contaminant control subsystem (TCCS) was directly integrated with the bleed stream from the carbon dioxide reduction subsystem. The TCCS performed as expected with minor anomalies. The test set the basis for further characterizing the TCCS performance as part of advance air revitalization system configurations. Author N91-10104# Pacific Northwest Lab., Richland, WA. Nuclear Systems and Concepts Dept. ADVANCED CERAMIC FABRIC BODY MOUNTED RADIATOR FOR SPACE STATION FREEDOM PHASE O DESIGN Brent J. Webb, Zen I. Antoniak, and Keith A. Pauley Jun. 1990 4 p Presented at the 5th AIAA/ASME Thermal Physics and Heat Transfer Conference, Seattle, WA, 18-20 Jun. 1990 (Contract DE-AC06-76RL-01830) (DE90-016361; PNL-SA-17526; CONF-900619-7) Avail: NTIS HC/MF A01 A body mounted radiator concept constructed of advanced ceramic fabric materials for use with the Phase O design of Space Station Freedom is described. The radiator is expected to weigh between 1.4 and 3.5 kg/sq m of single sided radiating surface, use ammonia working fluid, be highly deployable, and exhibit good reliability characteristics. This compares well with the 11.8 kg/sq m for two sided radiators proposed for the current space station design. DOE N91-10105*# Jet Propulsion Lab., California Inst. of Tech., A MOBILE SATELLITE EXPERIMENT (MSAT-X) NETWORK Charles C. Wang and Tsun-Yee Yan 15 Aug. 1990 56 p (NASA-CR-187336; JPL-Publ-90-19; NAS 1.26:187336; MSAT-X-164) Avail: NTIS HC/MF A04 CSCL 22B The network architecture development of the Mobile Satellite Experiment (MSAT-X) project for the past few years is described. The results and findings of the network research activities carried out under the MSAT-X project are summarized. A framework is presented upon which the Mobile Satellite Systems (MSSs) operator can design a commercial network. A sample network configuration and its capability are also included under the projected scenario. The Communication Interconnection aspect of the MSAT-X network is discussed. In the MSAT-X network structure two basic protocols are presented: the channel access protocol, and the link connection protocol. The error-control techniques used in the MSAT-X project and the packet structure are also discussed. A description of two testbeds developed for experimentally simulating the channel access protocol and link control protocol, |