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Preliminary tests in the NACA free-spinning wind tunnel

Description: Typical models and the testing technique used in the NACA free-spinning wind tunnel are described in detail. The results of tests on two models afford a comparison between the spinning characteristics of scale models in the tunnel and of the airplanes that they represent.
Date: October 29, 1935
Creator: Zimmerman, C. H.
Partner: UNT Libraries Government Documents Department
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Theory of High Frequency Rectification by Silicon Crystals

Description: The excellent performance of British ''red dot'' crystals is explained as due to the knife edge contact against a polished surface. High frequency rectification depends critically on the capacity of the rectifying boundary layer of the crystal. C. For high conversion efficiency, the product of this capacity and of the ''forward'' (bulk) resistance R{sub b} of the crystal must be small. For a knife edge, this product depends primarily on the breadth of the knife edge and very little upon its length. The contact can therefore have a rather large area which prevents burn-out. For a wavelength of 10 cm. the computations show that the breadth of the knife edge should be less than about 10{sup -3} cm. For a point contact the radius must be less than 1.5 x 10{sup -3} cm. and the resulting small area is conductive to burn-out. The effect of ''tapping'' is probably to reduce the area of contact.
Date: October 29, 1942
Creator: Bethe, H. A.
Partner: UNT Libraries Government Documents Department
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Metabolism and Distribution of Inhaled Plutonium in Rats

Description: From abstract: "Several different techniques were used to introduce tracer quantities of plutonium into the lungs of rats. When aerosols were produced by atomizing aqueous solutions of the nitrates it was found that approximately 20 per cent of the dose was absorbed and deposited in the skelton [sic] with tetra-, hexa-, and trivalent plutonium. Thus with these compounds, the lungs represent a more dangerous portal of entry than either oral (0.05 per cent) or intramuscular (13 per cent) administration. Tetravalent Pu was eliminated most slowly from the lung, the average half-time during the first month being 15 days. But when citrate was added to complex the Pu, over 70 per cent was eliminated within 1 day. This was accompanied by a deposition of over 30 per cent in the skelton [sic] and over 20 per cent in the liver. Presumably citrate breaks up the insoluble colloid in which Pu exists in the lungs. Complexing with cupferron which, unlike citrate, produces a "fat soluble" compound, greatly diminished the extent of absorption from the lungs. Plutonium oxide smokes which were produced at high temperatures were eliminated more slowly from the lungs (average half time of 30 days during the first month) and were deposited in the skeleton to a much lesser extent (6.2 per cent) than was the case with the nitrates."
Date: October 29, 1946
Creator: Abrams, Richard; Siebert, H. C.; Potts, A. M.; Forker, L. L.; Greenberg, D.; Postel, A. et al.
Partner: UNT Libraries Government Documents Department
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Aeronautical Characteristics of a Three-Blade Propeller Having NACA 10-(3)(08)-03 Blades

Description: "Data obtained in tests of a 10-foot diameter, three-blade propeller, having NACA 10-(3)(08)-03 blades, conducted in the Langley 16-foot high-speed tunnel are presented. The propeller performance quantities related by the tests are thrust, torque, efficiency, and advance ratio for various rotational speeds or stream Mach numbers with blade angle as a parameter. Advance Mach numbers varied from 0.12 to 0.64" (p. 1).
Date: October 29, 1948
Creator: Davidson, Robert E.
Partner: UNT Libraries Government Documents Department
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Flight Investigation of Loads on a Bubble-Type Canopy

Description: Report presenting the results of pressure-distribution measurements obtained in flight over the free-blown canopy of a fighter-type airplane. The measurements were compared to those of the same canopy in wind-tunnel testing to determine the degree of correlation and effects of Mach number and distortion on the pressure distribution.
Date: October 29, 1948
Creator: Matheny, Cloyce E. & Huston, Wilber B.
Partner: UNT Libraries Government Documents Department
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History of the reactivation of 100-B pile

Description: This report summarizes the preparations made for reactivation of the 100-B pile and the operational activities associated with the reactivation and subsequent operation up to the time of reaching desired power level. The period covered is from approximately June 1, 1948 until July 16, 1948.
Date: October 29, 1948
Creator: Filip, E. J.
Partner: UNT Libraries Government Documents Department
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Experimental investigation of base pressure on blunt-trailing-edge wings at supersonic velocities

Description: From Summary: "Measurements of base pressure are presented for 29 blunt-trailing-edge wings having an aspect ratio of 3.0 and various airfoil profiles. The different profiles comprised thickness ratios between 0.05 and 0.10, boattail angles between -2.9 degrees and 20 degrees, and ratios of trailing-edge thickness to airfoil thickness between 0.2 and 1.0. The tests were conducted at Mach numbers of 1.25, 1.5, 2.0, and 3.1. For each Mach number, the Reynolds number and angle of attack were varied. The lowest Reynolds number investigated was 0.2 x 10(6) and the highest was 3.5 x 10(6). Measurements on each wing were obtained separately with turbulent flow and laminar flow in the boundary layer. Span-wise surveys of the base pressure were conducted on several wings."
Date: October 29, 1951
Creator: Chapman, Dean R.; Wimbrow, William R. & Kester, Robert H.
Partner: UNT Libraries Government Documents Department
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Process considerations additional product concentration facilities in 202-S

Description: This memorandum discusses investigations concerning the coupling step required to adapt a Redox IIBP to a 234-5 feed which have indicated that a single peroxide strike from a solution 50--60 g./1. in product and about 2 M in nitric acid is adequate. Additional work is planned to demonstrate both peroxide and Pu(IV) oxalate strikes under these conditions. The present Redox PR cage product contains 10 g./1. in product and over 500 g./1. in nitric acid, and probably requires tow peroxide strikes; in addition, the operating capacity of the PR cage may be inadequate to process the throughputs desired in the Redox plant. A two stage continuous concentration process for Redox IIBP is jointly suggested by Design and Development and Chemical Development personnel, and is described in this document. This process is believed to be simple and easily operable. Acid is removed from the product solution adequately for the single peroxide strike coupling procedure. Batch size appears to be easily controllable.
Date: October 29, 1951
Creator: Tomlinson, R. E.
Partner: UNT Libraries Government Documents Department
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Influence of fuselage-mounted rocket boosters on flow field at inlet and on diffuser performance of strut-mounted engine at Mach numbers of 1.8 and 2.0

Description: Report presenting an investigation of the effect of fuselage-mounted rocket boosters on a strut-mounted engine in the 8- by 6-foot supersonic wind tunnel at Mach numbers of 1.8 and 2.0. The boosters were pairs of circular cylinders with conical forebodies mounted on the top and bottom of the fuselage, and the engine was mounted on a horizontal strut. Results regarding the characteristics of the flow field, effect of putting the boosters in several positions, and effect of angle of attack are provided.
Date: October 29, 1952
Creator: Wise, George A. & Obery, Leonard J.
Partner: UNT Libraries Government Documents Department
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Investigation of liquid fluorine and hydrazine-ammonia mixture in 100-pound-thrust rocket engine

Description: Report presenting the specific impulse, characteristic velocity, thrust coefficient, and heat rejection of liquid fluorine and a fuel consisting of a hydrazine-ammonia mixture for a range of fuel percentages in a 100-pound-thrust rocket engine designed for a combustion-chamber pressure of 300 pounds per square inch absolute. The fuel consisted of 59 percent hydrazine, 37 percent ammonia, and 4 percent water. The attainment of maximum performance with liquid fluorine as a rocket oxidant will require a critical study of injector design.
Date: October 29, 1952
Creator: Ordin, Paul M.; Rothenberg, Edward A. & Rowe, William H.
Partner: UNT Libraries Government Documents Department
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Investigation of several techniques for improving altitude starting limits of turbojet engines

Description: Report presenting a study of the altitude-starting limits of a production turbojet engine with an axial-flow compressor and a multiple through-flow combustor. The ignition limits, flame-propagation limits, and acceleration limits of the engine were improved to increase the starting limits to relatively high altitude.
Date: October 29, 1952
Creator: Armstrong, John C. & Wilsted, H. D.
Partner: UNT Libraries Government Documents Department
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Drag Measurements on Equivalent Bodies of Revolution of Six Configurations of the Convair MX-1964 (Originally MX-1626) Proposed Supersonic Bomber

Description: "Tests on equivalent bodies of revolution of six configurations of the Consolidated Vultee Aircraft Corporation proposed supersonic bomber (Convair MX-1964) have indicated that it is possible to reduce the drag of the configuration by designing it to have a favorable area distribution. The method of NACA RM L53I22c to predict the peak pressure drag of a configuration on the basis of its area distribution gave generally good agreement with the subject models" (p. 1).
Date: October 29, 1953
Creator: Hall, James Rudyard
Partner: UNT Libraries Government Documents Department
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Effect of Inlet-Air Temperature on Performance of a 16-Inch Ram-Jet Combustor

Description: Report presenting an investigation of the effect of inlet-air temperature on the combustion efficiency of a 16-inch ram-jet engine in a connected-pipe installation. The engine was operated over a range of fuel-air ratios with several different combustor configurations and two fuel types. Configurations tested included a sloping baffle and a can-type combustor in three configurations.
Date: October 29, 1953
Creator: Cervenka, A. J.; Dangle, E. E. & Friedman, Robert
Partner: UNT Libraries Government Documents Department
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Effective Thermal Conductivities of Magnesium Oxide Stainless Steel, and Uranium Oxide Powders

Description: Memorandum presenting testing conducted to determine the conductivity of magnesium oxide, stainless steel, and uranium oxide powders in various gases at a range of temperatures. Results regarding the experimental effective conductivities, comparison of analytical and experimental results, and effect of pressure on conductivity are provided.
Date: October 29, 1953
Creator: Eian, C. S. & Deissler, R. G.
Partner: UNT Libraries Government Documents Department
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Free-flight-tunnel investigation of the low-speed stability and control characteristics of a canard airplane model

Description: From Summary: "Since canard configurations have been found to possess unusual static stability characteristics, an investigation has been conducted in the Langley free-flight tunnel to determine the dynamic stability and control characteristics of a model of this type. The characteristics of the model were unsatisfactory in the higher lift-coefficient range because of lightly damped lateral oscillations and because of erratic behavior in pitch and yaw which was apparently caused by random trim changes associated with the irregular fluctuations in the vortex flow from the horizontal tail."
Date: October 29, 1953
Creator: Johnson, Joseph L., Jr. & Paulson, John W.
Partner: UNT Libraries Government Documents Department
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Investigation of translating-spike supersonic inlet as means of mass-flow control at Mach numbers of 1.5, 1.8, and 2.0

Description: Report presenting an investigation in the supersonic wind tunnel on a 50 degree conical-spike inlet at three Mach numbers over a range of angles of attack. The additive-drag penalty associated with inlet mass-flow spillage was significantly reduced by using a translating-spike inlet rather than a fixed-geometry inlet.
Date: October 29, 1953
Creator: Gorton, Gerald C.
Partner: UNT Libraries Government Documents Department
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Minimum Spark-Ignition Energies of 12 Pure Fuels at Atmospheric and Reduced Pressure

Description: Memorandum presenting minimum spark-ignition energies for 12 pure fuels measured at reduced pressure, and the data obtained were extrapolated to 1 atmosphere. Some of the fuels investigated included normal and cycloparaffins, olefins, carbon disulfide, and oxygenated compounds such as alcohol, ether, propylene oxide, and tetrahydropyran.
Date: October 29, 1953
Creator: Metzler, Allen J.
Partner: UNT Libraries Government Documents Department
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Stability and Control Characteristics at High Subsonic Speeds of a 1/30-Scale Model of the MX-1554A Design

Description: Report discussing testing on a model of the proposed MX-1554A design to determine its stability and control characteristics in high speed flight. Information about the effect of speed brakes, tanks, and fences on the longitudinal characteristics is also provided.
Date: October 29, 1953
Creator: Lockwood, Vernard E.; Luoma, Arvo A. & Solomon, Martin
Partner: UNT Libraries Government Documents Department
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Criticality studies of interacting cylindrical systems

Description: From introduction: "As a part of this program, this report presents the results of a study of an interacting system in which the conditions for criticality are given in terms of the concentration of fissionable material and the geometry of the system."
Date: October 29, 1954
Creator: Miraldi, F. D.; Farquhar, J., III & Perry, P. I.
Partner: UNT Libraries Government Documents Department
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Performance of 15-Stage Experimental J71 Axial-Flow Compressor: 2 - Individual Stage Performance Characteristics

Description: The first four stages were found to cause a major part of the poor low-speed efficiency of this compressor. The low design-speed over-all pressure ratio at surge was caused by the first and the twelfth to fifteenth stages. The multiple over-all performance curves in the intermediate-speed range were at least partly the result of double-branched characteristic curves for the third and seventh stages.
Date: October 29, 1954
Creator: Lucas, James G. & Filippi, Richard E.
Partner: UNT Libraries Government Documents Department
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Summary of Free-Flight Zero-Lift Drag Results from Tests of 1/5-Scale Models of the Convair YF-102 and F-102A Airplanes and Several Related Small Equivalent Bodies at Mach Numbers from 0.70 to 1.46

Description: From Summary: "One-fifth-scale rocket-propelled models of the Convair YF-102 and F-102A airplanes were tested to determine free-flight zero-lift drag coefficients through the transonic speed range at Reynolds numbers near those to be encountered by the full-scale airplane. Trim and duct characteristics were obtained along with measurements of total-, internal-, and base-drag coefficients. Additional zero-lift drag tests involved a series of small equivalent-body-of-revolution models which were launched to low supersonic speeds by means of a helium gun."
Date: October 29, 1954
Creator: Wallskog, Harvey A.
Partner: UNT Libraries Government Documents Department
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