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Partner
Collection
Technical Report Archive and Image Library
740
National Advisory Committee for Aeronautics Collection
509
Office of Scientific & Technical Information Technical Reports
227
TRAIL Microcard Collection
116
Texas State Publications
5
Docs In The News
2
Stillwater History Museum at the Sheerar, Stillwater, Oklahoma
2
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2
Boy and Girl Scout Annual Reports
1
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1
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NACA Research Memorandums
269
NACA Technical Notes
133
Atomic Energy Commission Reports
113
NACA Technical Reports
54
NACA Technical Memorandums
50
United States Bureau of Mines Reports
47
Hanford Works Reports
33
Report of investigations (United States. Bureau of Mines)
30
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29
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27
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Results:
961 - 980 of
980
Use of the Characteristics of Permalloy in Detecting a Predetermined Value of Magnetic Field or Current in a Time-Varying Electromagnet: 1/4 Scale Bevatron Operating Model, Magnetic Field Strength-Magnet Current Correspondence
In programming the sequence of events in the operational cycle of the bevatron, certain devices must be triggered at specific values of magnetic field strength in the gap. It is desirable that the time-jitter, which corresponds to field jitter, of the tirggering pulses be small. In the synchrotron this is done with peaking strips which are located in the fringing field of the gap.
Date:
March 24, 1949
Creator:
Richardson, R. E.; Shuey, R. L.; Younkin, R. & Stephan, W. J.
System:
The UNT Digital Library
Vibration of loosely mounted turbine blades during service operation of a turbojet engine with centrifugal compressor and straight-flow combustion chambers
Report presenting an experimental investigation to determine the vibration characteristics of loosely mounted turbine blades during service operation of a turbojet engine. High-temperature strain gages were used to measure turbine-blade vibrations. Results regarding oscillograph records, critical speeds and frequencies, vibratory-stress levels, and effect of tightening the blade mount are provided.
Date:
November 3, 1949
Creator:
Morgan, W. C.; Kemp, R. H. & Manson, S. S.
System:
The UNT Digital Library
Vibration Survey of Blades in 10-Stage Axial-Flow Compressor 1: Static Investigation
"An investigation was conducted to determine the cause of failures in the seventh- and tenth-stage blades of an axial-flow compressor. The natural frequencies of all rotor blades were measured and critical-speed diagrams were plotted. These data show that the failures were possibly caused by resonance of a first bending-mode vibration excited by a fourth order of the rotor speed in the seventh stage and a sixth order in the tenth stage" (p. 1).
Date:
January 31, 1949
Creator:
Meyer, André J., Jr. & Calvert, Howard F.
System:
The UNT Digital Library
Vibrational modes of several hollow turbine blades and of solid turbine blade of similar aerodynamic design
Experimental study to determine the vibrational modes of several hollow turbine blades and a solid turbine blade of similar aerodynamic design. Results regarding the significance of nodal patterns, vibrational modes of six blade types, and the probability of excitation in some of the blades are provided.
Date:
October 3, 1949
Creator:
Kemp, R. H. & Shifman, J.
System:
The UNT Digital Library
Water Pools in Pennsylvania Anthracite Mines
Report issued by the Bureau of Mines discussing water pools that accumulate in Pennsylvania anthracite mines. Factors that lead to underground water pools, and methods for water drainage are presented. This report includes tables, maps, illustrations, and photographs.
Date:
1949
Creator:
Ash, S. H.; Eaton, W. L.; Hughes, Karl; Romischer, W. M. & Westfield, J.
System:
The UNT Digital Library
Wind-Tunnel Investigation at Low Speeds of Various Plug-Aileron and Lift-Flap Configurations on a 42 Degree Sweptback Semispan Wing
Report presenting a wind-tunnel investigation on a 42 degree sweptback-wing model to determine the lateral control characteristics of a plug-aileron configuration. The configuration consisted of six segments extending from the wing 20-percent-span to the wing 80-percent-span stations and with the center of each plug on the wing 70-percent-chord line. Results regarding wing aerodynamic characteristics and lateral control characteristics are provided.
Date:
January 26, 1949
Creator:
Schneiter, Leslie E. & Watson, James M.
System:
The UNT Digital Library
Wind-tunnel investigation of a tailless triangular-wing fighter aircraft at Mach numbers from 0.5 to 1.5
Report presenting a wind-tunnel investigation to determine the respective variations with Mach number of the static longitudinal stability, the drag, and the effectiveness of a constant-chord control surface for a tailless fighter aircraft with a triangular wing of aspect ratio 2.31.
Date:
June 24, 1949
Creator:
Lawrence, Leslie F. & Summers, James L.
System:
The UNT Digital Library
Wind-Tunnel Investigation of an NACA 65-210 Semispan Wing Equipped With Circular Plug Ailerons and a Full-Span Slotted Flap
Note presenting a wind-tunnel investigation made of the lateral-control characteristics of a thin, low-drag, semispan wing equipped with three configurations of circular plug ailerons and a full-span, 25-percent-chord, slotted flap. The investigation was performed through a Mach number range of 0.13 to 0.61. Results regarding wing aerodynamic characteristics, aileron control characteristics, comparison of lateral-control characteristics of the three configurations of circular plug aileron, comparison of lateral-control characteristics of the circular plug ailerons, a conventional plug aileron, and a retractable aileron, and a comparison of lateral-control characteristics of the circular plug ailerons with those of a sealed plain aileron are provided.
Date:
January 1949
Creator:
Fischel, Jack
System:
The UNT Digital Library
Wind-tunnel investigation of horizontal tails. 5: 45 degree swept-back plan form of aspect ratio 2
Report presenting the results of a wind-tunnel investigation of the low-speed aerodynamic characteristics of a 45 degree sweptback horizontal-tail model of aspect ratio 2 and a comparison of these results with results for a model of the same aspect ratio with an unswept hinge line. Results regarding the lift and hinge-moment parameters, static longitudinal stability, effect of Reynolds number, effect of standard roughness, effect of removing elevator nose seal, and visualization of the air flow are provided.
Date:
September 27, 1949
Creator:
Dods, Jules B., Jr.
System:
The UNT Digital Library
Wind-Tunnel investigation of NACA 65,3-418 airfoil section with boundary-layer control through a single suction slot applied to a plain flap
Report presenting an investigation in the two-dimensional low-turbulence tunnel of the NACA 65,3-418 airfoil section with a 25-percent-airfoil-chord plain flap and a suction slot on the flap. The primary purpose of the investigation is to determine the effect of the type of boundary-layer control on the section lift-drag ratio.
Date:
February 23, 1949
Creator:
Horton, Elmer A. & von Doenhoff, Albert E.
System:
The UNT Digital Library
Wind-Tunnel Investigation of the Low-Speed Static Stability and Control Characteristics of a Model of Bell MX-776
An investigation has been made in the Langley stability tunnel to determine the low-speed static stability and control characteristics of a model of the Bell MX-776. The results of the investigation indicated that the basic model configuration was longitudinally stable in the angle-of-attack range from about -16 deg. to 16 deg. but that the stability was a minimum near O deg angle of attack. The data indicated an aerodynamic-center position about 0.64 body diameters behind the center of gravity at low angles of attack. Reduction in the size of the front horizontal fins increased the longitudinal stability. With 20 percent of the span of the normal front horizontal fins cut off the aerodynamic center was about 1.04 body diameters behind the center of gravity, and with front horizontal fins having the same area as the front vertical fins, the aerodynamic center was 2.26 body diameters behind the center of gravity (at low angles of attack).
Date:
July 6, 1949
Creator:
Queijo, M. J. & Michael, W. H., Jr.
System:
The UNT Digital Library
Wind-tunnel investigation of the opening characteristics, drag, and stability of several hemispherical parachutes
Report presenting an investigation to determine the opening characteristics of several hemispherical parachutes at airspeeds up to 200 miles per hour and to study the influence of the parachute design variables on the opening characteristics. The effects of design variables on the drag and stability characteristics of the parachutes were also evaluated.
Date:
April 1949
Creator:
Scher, Stanley H. & Gale, Lawrence J.
System:
The UNT Digital Library
Wind-tunnel investigation of the spinning characteristics of a model of a twin-tail low-wing personal-owner-type airplane with linked and unlinked rudder and aileron controls
Report presenting a spin investigation in the 20-foot free-spinning tunnel of a model of a twin-tail low-wing personal-owner-type airplane with linked and unlinked rudder and aileron controls. The model was tested for two wing loadings and three mass distributions. When the rudders and ailerons were linked for two-control operation, the model generally would not spin.
Date:
January 1949
Creator:
Klinar, Walter J. & Gale, Lawrence J.
System:
The UNT Digital Library
Wind-tunnel investigation of transonic aileron flutter
Report presenting a partial-span wing tested to determine the cause of a flutter which had occurred in high-speed flight. Changes were made to the wing stiffness, location of the center of gravity of the wing, and the mass balance of the aileron. Results regarding the effect of wing changes on flutter, effect of aileron changes on flutter, shock-wave study, and static aerodynamic coefficients are provided.
Date:
June 9, 1949
Creator:
Erickson, Albert L. & Mannes, Robert L.
System:
The UNT Digital Library
Wind-Tunnel Tests of a 0.16-Scale Model of the Douglas MX-656 Airplane at High Subsonic Speeds, 1, Stability and Control Characteristics
Wind tunnel tests of the 0.16-scale Douglas MX-656 model were made at low and high subsonic Mach numbers to investigate the static longitudinal- and lateral stability characteristics. The tests shows that undesirable changes in longitudinal stability at the stall were apparently caused by an altered downwash pattern at the tail. The jettisonable nose fins were highly destabilizing. Compressibility effects for the test Mach numbers were not detrimental to the longitudinal- or lateral-stability characteristics.
Date:
April 26, 1949
Creator:
Hamilton, William T. & Cleary, Joseph W.
System:
The UNT Digital Library
Wind-Tunnel Tests of a 0.16-Scale Model of the Douglas MX-656 Airplane at High Subsonic Speeds. 2 - Wing and Fuselage Pressure Distribution
From Summary: "Measurements of wing and fuselage pressure distributions were made at low and high subsonic Much numbers on a 0.16-scale model of the projected MX-656 research airplane. The MX-656 is a supersonic design utilizing a low-aspect-ratio wing and tail. Pressure-distribution measurements indicated that, although the critical Mach number of the wing was approximately 0.81 at 0 degree angle of attack, compressibility effects were of little significance below a Mach number of at least 0.90. The principal effect of compressibility was an increase in the pressure gradient over the after 30 percent of the wing chord, causing a tendency for the flow to separate."
Date:
August 22, 1949
Creator:
Cleary, Joseph W. & Mellenthin, Jack A.
System:
The UNT Digital Library
Wind-Tunnel Tests on Various Types of Dive Brakes Mounted in Proximity of the Leading Edge of the Wing
"The present report is concerned with a series of tests on a model airplane fitted with four types of dive flaps of various shapes, positions, and incidence located near the leading edge of the wing (from 5 to 20 percent of the wing chord). Tests were also made on a stub airfoil fitted with a ventral dive (located at 8 percent of the wing chord). The hinge moments of the dive flaps were measured" (p. 1).
Date:
May 1949
Creator:
Lattanzi, Bernardino & Bellante, Erno
System:
The UNT Digital Library
Wing-Tunnel Investigation at High Subsonic Speeds of the Lateral-Control Characteristics of an Aileron and a Stepped Spoiler on a Wing With Leading Edge Swept Back 51.3 Degrees
Report presenting a wind-tunnel investigation through a speed range from Mach number 0.30 to 0.90 to determine the lateral-control characteristics of a 20-percent-chord by 39-percent-semispan aileron and a 60-percent-semispan stepped spoilers on a semispan-wing model with aspect ratio of 3.06 with 51.3 degrees sweepback of the wing leading edge. The aileron rolling effectiveness decreased as the Mach number increased, while the spoiler rolling-moment effectiveness decreased with Mach number.
Date:
June 7, 1949
Creator:
Schneiter, Leslie E. & Hagerman, John R.
System:
The UNT Digital Library
Wing-tunnel investigation at low transonic speeds of the effects of number of wings on the lateral-control effectiveness of an RM-5 test vehicle
Report presenting an investigation to determine the effects of number of wings on the aileron rolling effectiveness of an RM-5 test vehicle using the free-rolling wind-tunnel testing technique through a speed range to Mach number 0.9. The wings tested had neither taper nor sweepback and were equipped with full-span 20-percent-chord sealed and faired ailerons. Results indicated that increasing the number of wings resulted in a decrease in rolling effectiveness so that results obtained from the test of the three-wing model were closer to conventional-airplane-configuration results than the four-wing data.
Date:
November 29, 1949
Creator:
Johnson, Harold S.
System:
The UNT Digital Library
Zinc-Lead Ore Reserves of the Tri-State District, Missouri-Kansas-Oklahoma
Report issued by the Bureau of Mines over studies of zinc-lead reserves in the tri-state area. The results of the studies are presented. This report includes tables, maps, and illustrations.
Date:
July 1949
Creator:
Ruhl, Otto; Allen, Simeon A. & Holt, Stephen P.
System:
The UNT Digital Library