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Congressional Research Service Reports
1,370
Office of Scientific & Technical Information Technical Reports
1,318
Technical Report Archive and Image Library
305
National Advisory Committee for Aeronautics Collection
183
Government Accountability Office Reports
141
TRAIL Microcard Collection
92
Texas State Publications
64
Harris and Eliza Kempner
25
John F. Kennedy Memorial Collection
13
John F. Kennedy, Dallas Police Department Collection
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NACA Research Memorandums
142
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70
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32
109th Congress
25
Oak Ridge National Laboratory Reports
25
San Antonio Board of Adjustment Monthly Report
23
San Antonio Monthly Permit Report
23
San Antonio Monthly Reports
23
Personal Papers (MS 80-0002)
21
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Results:
1 - 24 of
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Spontaneous Combustion of Hydrogen
It is shown by the author's experiments that hydrogen which escapes to the atmosphere through openings in the system may burn spontaneously if it contains dust. Purely thermal reasoning can not account for the combustion. It seems to be rather an electrical ignition. In order to determine whether the cause of the spontaneous ignition was thermo-chemical, thermo-mechanical, or thermo-electrical, the experiments in this paper were performed.
Date:
March 4, 1922
Creator:
Pothmann, P. & Nusselt, Wilhelm
System:
The UNT Digital Library
Water pressure distribution on a flying boat hull
This is the third in a series of investigations of the water pressures on seaplane floats and hulls, and completes the present program. It consisted of determining the water pressures and accelerations on a Curtiss H-16 flying boat during landing and taxiing maneuvers in smooth and rough water.
Date:
December 4, 1929
Creator:
Thompson, F. L.
System:
The UNT Digital Library
The effect of valve timing upon the performance of a supercharged engine at altitude and an unsupercharged engine at sea level
This investigation was conducted to determine the comparative effects of valve timing on the performance of an unsupercharged engine at sea level and a supercharged engine at altitude. The tests were conducted on the NACA universal test engine. The timing of the four valve events was varied over a wide range; the engine speeds were varied between 1,050 and 1,500 r.p.m.; the compression ratios were varied between 4.35:1 and 7.35:1. The conditions of exhaust pressure and carburetor pressure of a supercharged engine were simulated for altitudes between 0 and 18,000 feet. The results show that optimum valve timing for a supercharged engine at an altitude of 18,000 feet differs slightly from that for an unsupercharged engine at sea level. A small increase in power is obtained by using the optimum timing for 18,000 feet for altitudes above 5,000 feet. The timing of the intake opening and exhaust closing becomes more critical as the compression ratio is increased.
Date:
February 4, 1931
Creator:
Schey, Oscar W. & Biermann, Arnold E.
System:
The UNT Digital Library
Span-load distribution as a factor in stability in roll
"This report gives the results of pressure-distribution tests made to study the effects on lateral stability of changing the span-load distribution on a rectangular monoplane wing model of fairly thick section. Three methods of changing the distribution were employed: variation in profile along the span to a thin symmetrical section at the tip, twist from +5 degrees to -15 degrees at the tip, and sweepback from +20 degrees to -20 degrees. The tests were conducted in a 5-foot closed-throat atmospheric wind tunnel" (p. 567).
Date:
March 4, 1931
Creator:
Knight, Montgomery & Noyes, Richard W.
System:
The UNT Digital Library
Fuel vaporization and its effect on combustion in a high-speed compression-ignition engine
"The tests discussed in this report were conducted to determine whether or not there is appreciable vaporization of the fuel injected into a high-speed compression-ignition engine during the time available for injection and combustion. The effects of injection advance angle and fuel boiling temperature were investigated. The results show that an appreciable amount of the fuel is vaporized during injection even though the temperature and pressure conditions in the engine are not sufficient to cause ignition either during or after injection, and that when the conditions are such as to cause ignition the vaporization process affects the combustion. The results are compared with those of several other investigators in the same field" (p. 629).
Date:
May 4, 1932
Creator:
Rothrock, A. M. & Waldron, C. D.
System:
The UNT Digital Library
General Potential Theory of Arbitrary Wing Sections
The problem of determining the two dimensional potential flow around wing sections of any shape is examined. The problem is condensed into the compact form of an integral equation capable of yielding numerical solutions by a direct process. An attempt is made to analyze and coordinate the results of earlier studies relating to properties of wing sections. The existing approximate theory of thin wing sections and the Joukowski theory with its numerous generalizations are reduced to special cases of the general theory of arbitrary sections, permitting a clearer perspective of the entire field. The method which permits the determination of the velocity at any point of an arbitrary section and the associated lift and moments is described. The method is also discussed in terms for developing new shapes of preassigned aerodynamical properties.
Date:
November 4, 1932
Creator:
Theodorsen, T. & Garrick, I. E.
System:
The UNT Digital Library
Working Charts for the Determination of Propeller Thrust at Various Air Speeds
A set of propeller performance charts, based on a torque speed coefficient has been constructed from full-sized metal propeller data obtained in the NACA propeller-research tunnel.
Date:
December 4, 1933
Creator:
Hartman, Edwin P.
System:
The UNT Digital Library
A comparison of fuel sprays from several types of injection nozzles
This report presents the tests results of a series of tests made of the sprays from 14 fuel injection nozzles of 9 different types, the sprays being injected into air at atmospheric density and at 6 and 14 times atmospheric density. High-speed spark photographs of the sprays from each nozzle at each air density were taken at the rate of 2,000 per second, and from them were obtained the dimensions of the sprays and the rates of spray-tip penetration. The sprays were also injected against plasticine targets placed at different distances from the nozzles, and the impressions made in the plasticine were used as an indication of the distribution of the fuel within the spray. Cross-sectional sketches of the different types of sprays are given showing the relative sizes of the spray cores and envelopes. The characteristics of the sprays are compared and discussed with respect to their application to various types of engines.
Date:
December 4, 1934
Creator:
Lee, Dana W.
System:
The UNT Digital Library
Cooling characteristics of a 2-row radial engine
This report presents the results of cooling tests conducted on a calibrated GR-1535 Pratt and Whitney Wasp, Jr. Engine installed in a Vought X04U-2 airplane. The tests were made in the NACA full-scale tunnel at air speeds from 70 to 120 miles per hour, at engine speeds from 1,500 to 2,600 r.p.m., and at manifold pressures from 19 to 33 inches of mercury absolute. A Smith controllable propeller was used to facilitate obtaining the different combinations of engine speed, power, and manifold pressure.
Date:
December 4, 1934
Creator:
Schey, Oscar W. & Rollin, Vern G.
System:
The UNT Digital Library
Notes on New French Commercial Airplanes
This document discusses the types of commercial planes ordered by Air France. Characteristics of the Wibault 670, the Dewoitine D.620, Bloch 300, and the Potez 620 airplanes are included. Pictures and diagrams of these aircraft are also included.
Date:
April 4, 1935
Creator:
unknown
System:
The UNT Digital Library
Turbulence factors of NACA wind tunnels as determined by sphere tests
Report presents the results of drag and pressure tests of spheres having diameters of 2, 4, 6, 8, 10, and 12 inches in eight NACA wind tunnels, in the air ahead of the carriage in the NACA tank, and beneath an autogiro in flight .
Date:
February 4, 1936
Creator:
Platt, Robert C.
System:
The UNT Digital Library
Propulsion of a flapping and oscillating airfoil
Formulas are given for the propelling or drag force experience in a uniform air stream by an airfoil or an airfoil-aileron combination, oscillating in any of three degrees of freedom; vertical flapping, torsional oscillations about a fixed axis parallel to the span, and angular oscillations of the aileron about a hinge.
Date:
May 4, 1936
Creator:
Garrick, I. E.
System:
The UNT Digital Library
Characteristics of six propellers including the high-speed range
This investigation is part of an extensive experimental study that has been carried out at full scale in the NACA 20-foot tunnel, the purpose of which has been to furnish information in regard to the functioning of the propeller-cowling-nacelle unit under all conditions of take-off, climbing, and normal flight. This report presents the results of tests of six propellers in the normal and high-speed flight range and also includes a study of the take-off characteristics.
Date:
June 4, 1936
Creator:
Theodorsen, Theodore; Stickle, George W. & Brevoort, M. J.
System:
The UNT Digital Library
Tank Tests of the Effect of Rivet Heads, etc., on the Water Performance of a Seaplane Float, Special Report
"A 1/3.5 full-size model of the Mark V float of the Bureau of Aeronautics, Navy Department, was tested in the NACA tank both with smooth painted bottom surfaces and with roundhead rivets, plate laps, and keel plates fitted to simulate the actual bottom of a metal float. The augmentation in water resistance due to the added roughness was found to be from 10-12% at the hum speed and from 12-14% at high speeds. The effect of the roughness of the afterbody was found to be negligible except at high trims" (p. 1).
Date:
June 4, 1936
Creator:
Parkinson, J. B. & Robertson, J. B., Jr.
System:
The UNT Digital Library
Pressure-distribution measurements at large angles of pitch on fins of different span-chord ratio on a 1/40-scale model of the U. S. Airship "Akron"
Report presents the results of pressure-distribution measurements on a 1/40-scale model of the U. S. Airship "Akron" conducted in the NACA 20-foot wind tunnel. The measurements were made on the starboard fin of each of four sets of horizontal tail surfaces, all of approximately the same area but differing in span-chord ratio, for five angles of pitch varying from 11.6 degrees to 34 degrees, for four elevator angles, and at air speeds ranging from 56 to 77 miles per hour. Pressures were also measured at 13 stations along the rear half of the port side of the hull at one elevator setting for the same five angles of pitch and at an air speed of approximately 91 miles per hour. The normal force on the fin and the moment of forces about the fin root were determined. The results indicate that, ignoring the effect on drag, it would be advantageous from structural considerations to use a fin of lower span-chord ratio than that used on the "Akron.".
Date:
April 4, 1937
Creator:
McHugh, James G.
System:
The UNT Digital Library
Experimental Investigation of Wind-Tunnel Interference on the Downwash Behind an Airfoil
"The interference of the wind-tunnel boundaries on the downwash behind an airfoil has been experimentally investigated and the results have been compared with the available theoretical results for open-throat wind tunnels. As in previous studies, the simplified theoretical treatment that assumes the test section to be an infinite free jet has been shown to be satisfactory at the lifting line. The experimental results, however, show that this assumption may lead to erroneous conclusions regarding the corrections to be applied to the downwash in the region behind the airfoil where the tail surfaces are normally located" (p. 689).
Date:
June 4, 1937
Creator:
Silverstein, Abe & Katzoff, S.
System:
The UNT Digital Library
A theoretical study of lateral stability with an automatic pilot
"The influence of automatic operation of the aileron and rudder controls on the lateral stability of an airplane is discussed. The control deflections are assumed to be proportional to the deviations and to the rates of deviation of the airplane from steady-flight conditions. The effects of changes in the types of deviation governing control application are considered. For one simple method of control in which the aileron deflection is proportional to the angle of bank and the rudder deflection is proportional to the angle of yaw, the effect of lag in control application is studied and regions of stability with and without lag are given" (p. 273).
Date:
March 4, 1940
Creator:
Imlay, Frederick H.
System:
The UNT Digital Library
Preliminary Report on High Concentration Deuterium by Catalytic Exchange Reactions
From abstract: "This report contains the theoretical analysis of a plant to concentrate deuterium from 2 atoms% to 90 atoms% by the NH3-H2 exchange reaction."
Date:
February 4, 1943
Creator:
Mayer, Harris & Bonner, Robert
System:
The UNT Digital Library
A Theoretical Investigation of the Lateral Oscillations of an Airplane With Free Rudder With Special Reference to the Effect of Friction
"Charts showing the variation in dynamic stability with the rudder hinge-moment characteristics are presented. A stabilizing rudder floating tendency combined with a high degree of aerodynamic balance is shown to lead to oscillations of increasing amplitude. This dynamic instability is increased by viscous-friction in the rudder control system" (p. 147).
Date:
March 4, 1943
Creator:
Greenberg, Harry & Sternfield, Leonard
System:
The UNT Digital Library
The Effect of Fast Fission on k
The importance of fast neutron fission (i.e., fission caused by neutrons before being slowed down) was recognized by Szilard, and calculations similar to the present one have already been carried out by him, Feld, Ashkin, Wheeler, Wigner and others. The purpose of the present paper is to give a general formula for the contribution of fast fission to the multiplication constant, which will include all the cases already considered and will be applicable to more complicated geometries than those considered by the previous writers.
Date:
May 4, 1943
Creator:
Castle, H.; Ibser, H.; Sacher, G. & Weinberg, Alvin Martin, 1915-2006
System:
The UNT Digital Library
Progress Report: Development and Construction of Alpha-Counting Equipment
Abstract: An ionization chamber for use in counting alpha particle activity from the air has been devised for counting samples collected with the electrostatic precipitator. The chamber is an adaptation of the breech-locking standard chamber, with a cylindrical high voltage electrode into which the collection foil is placed, and a coaxial rod as a collecting electrode. A geometrical efficiency of close to 50% is obtained.
Date:
July 4, 1944
Creator:
Borkowski, C. J.; Dandl, R. A.; East, J. K. & Firminhac, R. H.
System:
The UNT Digital Library
Engineering Group Instrument Specification Report : Tests on Aquadag Treated Polyethylene Cable
Effect of aquadag coating on noise reduction in polyethylene coaxial cable was tested. A satisfactory combination of coaxial cables and connectors interconnecting sources of small ion currents or ionizing impulses with the measuring device is described.
Date:
September 4, 1944
Creator:
Weller, Barton L. & Dorsey, John M.
System:
The UNT Digital Library
[Tolerance requirements]
This report consists of a discussion concerning maximum allowable tolerance dose for personnel working in a contaminated area on an 8 hour per day basis. It is a follow up of a telephone conversation between the Medical Superintendent at Hanford Works and Dr. Robert Lash of Knoxville, Tennessee on April 13, 1943. (CBS)
Date:
September 4, 1944
Creator:
Norwood, W. D.
System:
The UNT Digital Library
Flying Qualities of a High-Speed Bomber With a Dual Pusher Propeller Aft of the Empennage as Estimated From Wind-Tunnel Tests of a 1/8-Scale Powered Model
Report discussing the flying qualities of a high-speed bomber with a dual pusher propeller aft of the empennage. The airplane was found to have satisfactory flying qualities except for stability issues with aft center of gravity, high elevator control forces in landing, insufficient elevator control in take-off, and low rudder-free directional stability.
Date:
November 4, 1944
Creator:
Weiberg, James A. & Schnurbusch, Alfred W.
System:
The UNT Digital Library