« iepriekšējāTurpināt »
Includes sound generation, transmission, and attenuation.
For noise pollution see 45 Environment Pollution.
AND SPACE POLICY
3234 Includes NASA appropriation hearings; aviation law; space law and policy; international law; international cooperation, and patent policy.
72 ATOMIC AND MOLECULAR PHYSICS 3221
Includes atomic structure, electron properties, and molecular spectra.
73 NUCLEAR AND HIGH-ENERGY PHYSICS
N.A. Includes elementary and nuclear particles; and reactor theory.
For space radiation see 93 Space Radiation.
85 URBAN TECHNOLOGY AND
3235 Includes applications of space technology to urban problems; technology transfer; technology assessment; and surface and mass transportation.
For related information see 03 Air Transportation and Safety, 16 Space Transportation, and 44 Energy Production and Conversion.
Includes space sciences (general); astronomy; as
trophysics; lunar and planetary exploration; solar physics; 75 PLASMA PHYSICS
and space radiation.
For related information see also Geosciences. Includes magnetohydrodynamics and plasma fusion. For ionospheric plasmas see 46 Geophysics. For
88 SPACE SCIENCES (GENERAL)
N.A. space plasmas see 90 Astrophysics.
89 ASTRONOMY 76 SOLID-STATE PHYSICS
3227 Includes superconductivity.
Includes radio, gamma-ray, and infrared astronomy; For related information see also 33 Electronics and
and astrometry. Electrical Engineering and 36 Lasers and Masers.
3235 T7 THERMODYNAMICS AND
Includes cosmology; celestial mechanics; space plasSTATISTICAL PHYSICS
mas; and interstellar and interplanetary gases and dust.
For related information see also 75 Plasma Physics. Includes quantum mechanics; theoretical physics; and Bose and Fermi statistics.
91 LUNAR AND PLANETARY For related information see also 25 Inorganic and Phys
3238 ical Chemistry and 34 Fluid Mechanics and Heat Transfer.
Includes planetology; and manned and unmanned
flights. SOCIAL SCIENCES
For spacecraft design or space stations see 18 SpaceIncludes social sciences (general); administration and
craft Design, Testing and Performance. management; documentation and information science; economics and cost analysis; law, political science, and
92 SOLAR PHYSICS
3239 space policy; and urban technology and transportation.
Includes solar activity, solar flares, solar radiation and
sunspots. 80 SOCIAL SCIENCES (GENERAL)
For related information see 93 Space Radiation. Includes educational matters.
93 SPACE RADIATION
3239 81 ADMINISTRATION AND
Includes cosmic radiation; and inner and outer earth's MANAGEMENT
radiation belts. Includes management planning and research.
For biological effects of radiation see 52 Aerospace
Medicine. For theory see 73 Nuclear and High-Energy 82 DOCUMENTATION AND
Physics INFORMATION SCIENCE
3233 Includes information management; information stor
GENERAL age and retrieval technology; technical writing; graphic arts; and micrography.
Includes aeronautical, astronautical, and space sciFor computer documentation see 61 Computer Pro
ence related histories, biographies, and pertinent reports gramming and Software.
too broad for categorization; histories or broad overviews
of NASA programs. 83 ECONOMICS AND COST ANALYSIS
3234 Includes cost effectiveness studies.
N.A. Note: N.A. means that no abstracts were assigned to this category for this issue.
1-1 1-51 1-59 1-69
CONTRACT OR GRANT
The second Control Of Flexible Structures Flight Experiment
VOLUME 27 NUMBER 22 / NOVEMBER 23, 1989
Scientific and Technical Aerospace Reports
A Semimonthly Publication of the National Aeronautics and Space Administration
01 AERONAUTICS (GENERAL)
N89-27632# Army Aviation Engineering Flight Activity, Edwards
Testing was conducted to establish a performance baseline of the 12th year production UH-60A helicopter. A total of 19.5 productive hours were flown at two different test sites between 15 August and 2 September 1988. The performance of the 12th year production UH-60A Black Hawk was similar to or slightly degraded from the sixth year production UH-60A. At the primary mission gross weight, the performance met the requirement of the Prime Item Development Specification (PIDS). The out-of-ground effect hover gross weight capability was 17,416 pounds for 95 percent intermediate (30 minute limit) rated power available at 4000 feet pressure altitude and 35 C temperature. The vertical rate of climb of the 12th year aircraft exceeded the PIDS requirement by 21 ft/min. The 12th year production aircraft has an increase in equivalent flat plate area over the sixth year production aircraft. At 4000 ft pressure altitude, 35 C, and maximum continuous power, the cruise airspeed is 139 knots true airspeed, equal to the PIDS requirement.
N89-27634*# National Aeronautics and Space Administration.
An investigation was conducted in the Static Test Facility of the Langley 16-Foot Transonic Tunnel
dual-port, nonaxisymmetric, block-and-turn type thrust reverser model with vane cascades in the reverser ports which turned the flow in the splay direction and aided in turning the flow in the reverse direction. Splaying reverser flow is a method of delaying to lower landing ground roll speeds the reingestion of hot exhaust flow into the inlets. Exhaust flow splay can also help prevent the impingement of hot exhaust gases on the empennage surfaces when the reverser is integrated into an actual airframe. The vane cascades consisted of two sets of perpendicular vanes with a variable number of turning and splay vanes. A skewed vane box was also tested which had only one set of vanes angled to provide both turning and splay. Vane cascades were designed to provide different amounts of flow splay in the top and bottom ports. Inner doors, trim tabs, and an orifice plate all provided means of varying the port area for reverser flow modulation. The outer door position was varied as a means of influencing the flow reverse angle. Nozzle pressure ratio was varied from 1.75 to approximately 6.00.
Includes aerodynamics of bodies, combinations, wings, rotors, and control surfaces; and internal flow in ducts and turbomachinery.
For related information see also 34 Fluid Mechanics and Heat Transfer.
N89-27635# Pacific-Sierra Research Corp., Los Angeles, CA. AEROSTAT COLD WEATHER STUDY Technical Report, 6 Mar.
31 Dec. 1988 Dennis L. Kane 13 Mar. 1989 59 p (Contract MDA903-88-C-0020) (AD-A207299; PSR-1925) Avail: NTIS HC A04/MF A01 CSCL 04/2
The artic environment and its potential impact on Aerostat design and operations are discussed. Predictive meteorological resources available are summarized. Results of previous Aerostat operations in cold climates are reviewed and potential solutions discussed for the problems encountered.
N89-27633# Vigyan Research Associates, Inc., Hampton, VA. LOW DENSITY FLOW EFFECTS FOR HYPERVELOCITY VEHICLES Final Report, Aug. 1986 - Jul. 1987 Roop N. Gupta Mar. 1989 41 p (Contract F33615-86-C-3009) (AD-A206218; WRDC-TR-89-3034) Avail: NTIS HC A03/MF A01 CSCL 20/4
This work presents results for the surface pressure, drag, heat transfer and skin-friction coefficients for hyperboloids and sphere-cone shaped slender and wide-angle bodies under varying degrees of low-density flow conditions. Recently obtained surface-slip and the corrected shock-slip conditions are employed to account for the low-density effects. The flow cases analyzed include highly cooled and very long slender bodies in high Mach number flows. The present method (limited to the analysis of a perfect gas here) is found to predict various flow field quantities quite accurately when compared with the experimental data.
N89-27636# Air Force Armament Lab., Eglin AFB, FL. HYPERSONIC PREDICTION COMPARISONS WITH EXPERIMENTAL DATA FOR A CONE-CYLINDER AT MACH 6.86 Final Report, Oct. 1988 - Jan. 1989 Montgomery C. Hughson and Charles J. Cottrell Mar. 1989 10 p Previously announced in IAA as A89-25419 (AD-A207583; AFATL-TP-89-04) Avail: NTIS HC A02/MF A01 CSCL 20/4
Comparisons of computed flowfield predictions to experimental data for a cone-cylinder configurations at Mach 6.86 and angles of attack of 0, 6.7, 14, and 20 degrees are presented. The two inviscid computer codes used were EAGLE and ZEUS, which represent a time-iterative and a space-marching approach, respectively. Specific comparisons were made between the predicted and the experimental pressure distributions along the body at various circumferential locations, as well as aerodynamic characteristics of normal force coefficient and the location of the center of pressure. The inviscid calculations compare well with experimental data where viscous effects are minimal. GRA
and Mach numbers of eddies, the Fourier spectrum of the velocity, and pressure field at a number of locations within the shear layer.
N89-27637# National Aeronautical Lab., Bangalore (India).
A simple approach has been developed to use the two dimensional grid generation method by solving elliptic partial differential equations to generate the three dimensional grid for wing-fuselage configurations. This simple method can be applied to generate grids for an arbitrary fuselage fitted with any swept wing with dihedral. A three dimensional transonic analysis code TWING, with an approximate factorization (AF2) scheme has been suitably used as a flow solver. As an example, RAE-WING-A with body-B2 configuration has been considered. The results obtained have been compared with available numerical and experimental results. It has been observed in the present computations that AF2 scheme is not sensitive to grid stretching.
N89-27640# McDonnell Douglas Research Labs., Saint Louis, MO. Dept. of Flight Sciences. TERMINAL SHOCK RESPONSE IN RAMJET INLETS TO ABRUPT DOWNSTREAM PERTURBATIONS Final Report, 29 Sep. 1983 - 30 Jun. 1987 Miklos Sajben, Thomas J. Bogar, and Joseph C. Kroutil Sep. 1988 47 p (Contract N60530-83-C-0186) (AD-A209788; AD-E900851; MDC-Q1285; NWC-TP-6846) Avail: NTIS HC A03/MF A01 CSCL 21/5
The response of a nominally two-dimensional transonic diffuser flow to abrupt downstream perturbations examined experimentally.
N89-27641# University of Southern California, Los Angeles. Dept. of Aerospace Engineering. STUDIES OF UNSTEADY VORTEX FLAP AERODYNAMICS Final Report, 1 Aug. 1985 - 31 Jan. 1989 T. Maxworthy and H. K. Cheng 20 Jun. 1989 5p (Grant AF-AFOSR-0318-85; AF Proj. 2307) (AD-A209837; AFOSR-89-0933TR) Avail: NTIS HC A02/MF A01 CSCL 01/1
A joint theoretical and experimental program on the unsteady aerodynamics associated with active vortex flaps employed on delta wings was conducted. Flow visualizations were performed along with quantitative flow field measurements via particle tracking techniques for a range of dynamic conditions. Additionally, a theoretical point vortex approach was employed to study the vortex dynamics and resultant unsteady loads.
N89-27638# General Dynamics Corp., Fort Worth, TX. SMALL SCALE MODEL TESTS IN SMALL WIND AND WATER TUNNELS AT HIGH INCIDENCE AND PITCH RATES. VOLUME 3: WATER TUNNEL (HFF) DATA BASE Final Report, Sep. 1985 - Sep. 1988 Atlee M. Cunningham, Jr., Todd Bushlow, John R. Mercer, Tim A. Wilson, and Steve N. Schwoerke Apr. 1989 179 p (Contract N00014-85-C-0419) (AD-A208690) Avail: NTIS HC A09/MF A01 CSCL 01/1
The force testing of small scale models in either a small wind tunnel or a water tunnel was investigated as an inexpensive and quick means to obtain meaningful dynamic force and moment data representative of rapidly maneuvering full scale aircraft. Force tests of flatplate semispan models were conducted in the General Dynamics Aerodynamic Development Facility (ADF) which is a small 14x14 sq in. low speed wind tunnel. Oscillatory model motions up to 48 deg (peak to peak) amplitude were tested at frequencies of 1 to 3 Hz. Force tests of flat and three-dimensional full span models were conducted in the General Dynamics Hydroflow Facility (HFF) which is a horizontal flow water tunnel with a 24x24 sq in. test section.
03 AIR TRANSPORTATION AND SAFETY
Includes passenger and cargo air transport operations; and aircraft accidents.
For related information see also 16 Space Transportation and
85 Urban Technology and Transportation.
N89-27639# Georgia Inst. of Tech., Atlanta. School of Aerospace Engineering. NUMERICAL SIMULATION OF CONTROL OF SUPERSONIC SHEAR LAYERS Semiannual Progress Report, 1 Dec. 1988 31 May 1989 L. N. Sankar and Tang Wei 31 May 1989 33 p (Contract N00014-89-J-1319) (AD-A209703) Avail: NTIS HC A03/MF A01 CSCL 2074
The objective of the present research is to investigate the stability and growth characteristics of 2-D and 3-D supersonic free shear layers through direct numerical solution of the 3-D compressible viscous flow equations. An explicit time marching method, patterned after the well known MacCormack scheme is used to integrate the 2-D and 3-D Navier-Stokes equations in time, on a stretched Cartesian grid. The flow being studied consists of shear layers formed at the juncture of two parallel streams at different Mach numbers, densities and temperatures. Assuming an initial velocity, density and temperature distribution at an upstream location, the mean steady flow characteristics of the shear layer are first computed. This is done by marching in time, until an asymptotically steady state solution for the mean flow is obtained. Next, acoustic disturbances composed of streamwise, normal or spanwise sinusoidal velocity perturbations at known frequencies are imposed on the shear layer. The limit cycle behavior of the shear layer is then computed by carrying out the calculations for several cycles of the imposed disturbance. The computed flow field properties are post-processed using standard graphics, techniques to obtain vorticity, pressure and density plots, velocity
N89-27642# Sandia National Labs., Albuquerque, NM.
The objective of this paper is to analyze the severity of aircraft accidents that may involve the air transport of radioactive materials (RAM). One of the basic aims of this paper is to provide a numerical description of the severity of aircraft transport accidents so that the accident severity can be compared with the accident performance standards that are specified in the International Atomic Energy Authority (IAEA) Safety Series 6, the international packaging standards for the safe movement of RAM. The existing packaging regulations in most countries embrace the packaging standards developed by the IAEA. Historically, the packaging standards for Type B packages have been independent of the transport mode. That is, if the shipment occurs in a certified packaging, then the shipment can take place by any transport mode. In 1975, a legislative action in the U.S. Congress led to the development of a package designed specifically for the air transport of plutonium. Changes were subsequently made to the U.S. packaging regulations to incorporate the plutonium air transport performance standards. These standards were used to certify the air transport package for plutonium which is commonly referred to as PAT-1 (U.S. NRC). The PAT-1 was certified by the U.S. Nuclear Regulatory Commission in September 1978.
DOE protecting (for future use) an available maneuver option for one or more of the involved aircraft. Routinely, a single such maneuver option causes complex problems to be broken into independent, smaller, and simpler problems.
N89-27643# Lockheed Aeronautical Systems Co., Burbank, CA.
Three contemporary fuel tank installation configurations investigated in this study include: (1) a conformable tank containing a bladder and supported within a dedicated structure; (2) a double wall cylindrical strap in an auxiliary tank; and (3) bladder cells fitted in the lower fuselage. Existing crash design criteria are reviewed, as well as current proposals which could affect fuel tank installations. Program KRASH was used to help evaluate the performance of a fuselage mounted tank when subjected to dynamic loads. A total of 21 cases were analyzed, including 12 vertical impacts and 9 longitudinal pulse conditions and/or configurations. The analytical models included 120-inch sections, 300-inch segments and full airplane representations. Results in the form of floor and fuel tank accelerations, floor and fuel tank attachment loads and fuselage crush were obtained. Two test conditions are proposed to represent conditions that best meet the crash design criteria developed in a previous FAA sponsored parametric study, as well as to recognize realistic structures and tests that can be run.
N89-27646# Mitre Corp., McLean, VA. Civil Systems Div.
An algorithm, called Gentle-Strict (GS), is given for automated resolution of crossing conflicts between two aircraft, using parallel lateral offset maneuvers. Though other algorithms have been proposed for this purpose, GS uniquely facilitates quantitative analysis of the conflict resolution process itself, as well as quantitative analysis of the links between pairwise conflict resolution and longer lookahead air traffic control (ATC) strategies. The main result of this document is a closed form mathematical formula which relates parameterizations of: (1) the encounter geometry; (2) the pathkeeping uncertainties; (3) the minimum separation achieved by GS; and (4) the gentleness of parallel lateral offset resolution maneuvers (as parameterized by magnitude of offset and by induced delay upon the aircraft).
N89-28178*# National Aeronautics and Space Administration.
p 223-225 (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 17G
N89-27644# Federal Aviation Administration, Washington, DC.
Forecasts are present for aviation activity of 850 airports in the United States for fiscal years 1989 to 2005. These include 398 airports with FAA air traffic control towers and radar approach control service and 17 FAA contract towers. For each, airport, detailed forecasts are made for the four major users of the air traffic system: air carriers, air taxi/commuters, aviation, and military. Summary tables contain national, FAA regional, and State aviation data and other airport specific highlights. The forecasts have been prepared to meet the budget and planning needs of the constituent units of the FAA headquarters and regional offices and to provide airport-specific information that can be used by State and local aviation authorities, the aviation industry, as a whole, and the general public.
N89-28179*# National Aeronautics and Space Administration.
p 227-229 (For primary document see N89-28118 22-48) Avail: NTIS HC A12/MF A01 CSCL 17G
05 AIRCRAFT DESIGN, TESTING AND
Includes aircraft simulation technology.
For related information see also 18 Spacecraft Design, Testing and Performance and 39 Structural Mechanics.For land transportation vehicles see 85 Urban Technology and Transportation.
04 AIRCRAFT COMMUNICATIONS AND
Includes digital and voice communication with aircraft; air navigation systems (satellite and ground based); and air traffic control.
For related information see also 17 Space Communications, Spacecraft Communications, Command and Tracking and Communications and Radar.
N89-27645# Mitre Corp., McLean, VA. Civil Systems Div.
The Maneuver Option Manager (MOM), a methodology to simplify complex air traffic control (ATC) problems is described. A complex problem is identified here as a set of interrelated potential conflicts between pairs of aircraft. It may involve arbitrarily many aircraft. MOM determines which of six simple maneuver options is available (free of such potential conflicts) for each aircraft. These options involve limited displacements left/right ahead/behind above/below nominal. MOM simplifies a complex problem by
N89-27647*# Boeing Commercial Airplane Co., Seattle, WA.
A system of study of the potential for a high speed commercial transport aircraft addressed technology, economic, and environmental constraints. Market projections indicated a need for fleets of transport with supersonic or greater cruise speeds by the years 2000 to 2005. The associated design requirements called for a vehicle to carry 250 to 300 passengers over a range of 5000 to 6000 nautical miles. The study was initially unconstrained in terms of vehicle characteristics, such as cruise speed, propulsion systems, fuels, or structural materials. Analyses led to a focus on the most promising vehicle concepts. These were concepts that used a kerosene type fuel and cruised at ach numbers between 2.0 to 3.2. Further systems study identified the impact of