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The effect of high solidity on propeller characteristics at high forward speeds from wind-tunnel tests of the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 two-blade propellers

Description: From Summary: "Tests of two-blade propellers having the NACA 4-(3)(06.3)-06 and NACA 4-(3)(06.4)-09 blade designs (blade activity factors of 179 and 263, respectively) have been made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 70 degrees for free-stream Mach numbers from 0.165 to 0.725 to determine the effects of high solidity and compressibility on propeller characteristics. The tests are part of a general investigation of propellers at high forwar… more
Date: February 27, 1947
Creator: Delano, James B.
Partner: UNT Libraries Government Documents Department
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Lateral Stability Characteristics of a 1/8.33-Scale Powered Model of the Republic XF-12 Airplane

Description: "The XF-12 airplane is a high-performance photo-reconnaissance aircraft designed for the Army Air Forces by the Republic Aviation Corporation. An investigation of a 1/8.33 - scale powered model was made in the Langley l9-foot pressure tunnel to obtain information relative to the aerodynamic design of the airplane. The model was tested with and without the original vertical tail. and with two revised tails. For the revised tail no. 1, the span of the original vertical .tail was increased about 1… more
Date: February 27, 1947
Creator: Pepper, Edward & Foster, Gerald V.
Partner: UNT Libraries Government Documents Department
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Minimum Specific Fuel Consumption of a Liquid-Cooled Multicylinder Aircraft Engine as Affected by Compression Ratio and Engine Operating Conditions

Description: From Summary: "An investigation was conducted on a 12-cylinder V-type liquid-cooled aircraft engine of 1710-cubic-inch displacement to determine the minimum specific fuel consumption at constant cruising engine speed and compression ratios of 6.65, 7.93, and 9.68. At each compression ratio, the effect.of the following variables was investigated at manifold pressures of 28, 34, 40, and 50 inches of mercury absolute: temperature of the inlet-air to the auxiliary-stage supercharger, fuel-air ratio… more
Date: February 26, 1947
Creator: Brun, Rinaldo J.; Feder, Melvin S. & Harries, Myron L.
Partner: UNT Libraries Government Documents Department
open access

Drag characteristics of rectangular and swept-back NACA 65-009 airfoils having aspect ratios of 1.5 and 2.7 as determined by flight tests at supersonic speeds

Description: Report presenting tests to determine the effects of sweepback angle and aspect ratio on the drag of an NACA 65-009 airfoil at supersonic speeds. The results indicated that for the range of Mach numbers investigated, increasing the sweepback angle and decreasing the aspect ratio reduced the value of the wing drag coefficient.
Date: February 24, 1947
Creator: Alexander, Sidney R. & Katz, Ellis
Partner: UNT Libraries Government Documents Department
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Calculations of the Supersonic Wave Drag of Nonlifting Wings with Arbitrary Sweepback and Aspect Ratio: Wings Swept Behind the Mach Lines

Description: "On the basis of a recently developed theory for finite sweptback wings at supersonic speeds, calculations of the supersonic wave drag at zero lift were made for a series of wings having thin symmetrical biconvex sections with untapered plan forms and various angles of sweepback and aspect ratios. The results are presented in a unified form so that a single chart permits the direct determination of the wave drag for this family of airfoils for an extensive range of aspect ratio and sweepback an… more
Date: February 21, 1947
Creator: Harmon, Sidney M. & Swanson, Margaret D.
Partner: UNT Libraries Government Documents Department
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Investigation of High-Performance Fuels in Multicylinder and in Single-Cylinder Engines at High and Cruising Engine Speeds

Description: "An investigation was conducted to compare the knock-limited performance of a 20-percent triptane blend in 28-K fuel with that of 28-R and 33-R fuels at high engine speeds, cruising speeds, and two compression ratios in an K-1830-94 multicylinder engine. Data were obtained with the standard compression ratio of 6.7 and with a compression ratio of 3.0. The three fuels were investigated at engine speeds of 1800, 2250, 2600, and 2800 rpm at high and low blower ratios" (p. 1).
Date: February 21, 1947
Creator: Bell, Arthur H.; Nelson, R. Lee & Richard, Paul H.
Partner: UNT Libraries Government Documents Department
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Preliminary Tests at Supersonic Speeds of Triangular and Swept-Back Wings

Description: Report presenting testing of a series of thin, triangular plan-form wings, including eight triangular wings of vertex angles and three swept-back wings with circular-arc sections. Results regarding lift, center of pressure, and ideal operation of different types of wings are provided.
Date: February 21, 1947
Creator: Ellis, Macon C., Jr. & Hasel, Lowell E.
Partner: UNT Libraries Government Documents Department
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Drag Measurements of a 34 Degree Swept-Forward and Swept-Back NACA 65-009 Airfoil of Aspect Ratio 2.7 as Determined by Flight Tests at Supersonic Speeds

Description: Report presenting the results of flight testing to determine the zero-lift drag of an NACA 65-009 airfoil at a specified aspect ratio. The results are compared to previous testing of unswept and swept-back arrangements. The swept-forward and swept-back airfoils were found to produce lower values of zero-drag lift than the unswept airfoil.
Date: February 20, 1947
Creator: Alexander, Sidney R.
Partner: UNT Libraries Government Documents Department
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An Analytical Investigation of the Heat Losses from a U.S. Navy K-Type Airship

Description: From Summary: "The heat losses from the envelope surface of a U.S. Navy K-type airship are evaluated to determine if the use of heat is a feasible means of preventing ice and snow accumulations on lighter-than-air craft during flight and when moored uncovered. Consideration is given to heat losses in clear air (no liquid water present in the atmosphere) and in probable conditions of icing and snow. The results of the analysis indicate that the amount of heat required in flight to raise the surf… more
Date: February 17, 1947
Creator: Hillendahl, Wesley H. & George, Ralph E.
Partner: UNT Libraries Government Documents Department
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Tank Tests of 1/5.5-Scale Forward Dynamic Model of the Columbia XJL-1 Amphibian - Langley Tank Model 208, TED No. NACA 2336

Description: Tests of a powered dynamic model of the Columbia XJL-1 amphibian were made in Langley tank no.1 to determine the hydrodynamic stability and spray characteristics of the basic hull and to investigate the effects of modifications on these characteristics. Modifications to the forebody chime flare, the step, and the afterbody, and an increase in the angle of incidence of the wing were included in the test program. The seaworthiness and spray characteristics were studied from simulated taxi runs in… more
Date: February 17, 1947
Creator: Havens, Robert F.
Partner: UNT Libraries Government Documents Department
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Flight Comparison of Performance and Cooling Characteristics of Exhaust-Ejector Installation with Exhaust-Collector-Ring Installation

Description: Flight and ground investigations have been made to compare an exhaust-ejector installation with a standard exhaust-collector-ring installation on air-cooled aircraft engines in a twin-engine airplane. The ground investigation allowed that, whereas the standard engine would have overheated above 600 horsepower, the engine with exhaust ejectors cooled at take-off operating conditions at zero ram. The exhaust ejectors provided as much cooling with cowl flaps closed as the conventional cowl flaps i… more
Date: February 14, 1947
Creator: Acker, Loren W. & Kleinknecht, Kenneth S.
Partner: UNT Libraries Government Documents Department
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High-Speed Wind-Tunnel Tests of a Model of the Lockheed YP-80A Airplane Including Correlation with Flight Tests and Tests of Dive-Recovery Flaps

Description: "This report contains the results of tests of a 1/3-scale model of the Lockheed YP-90A "Shooting Star" airplane and a comparison of drag, maximum lift coefficient, and elevator angle required for level flight as measured in the wind tunnel and in flight. Included in the report are the general aerodynamic characteristics of the model and of two types of dive-recovery flaps, one at several positions along the chord on the lower surface of the wing and the other on the lower surface of the fuselag… more
Date: February 14, 1947
Creator: Cleary, Joseph W. & Gray, Lyle J.
Partner: UNT Libraries Government Documents Department
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An Investigation of the Effects of Sweep on the Characteristics of a High-Aspect-Ratio Wing in the Langley 8-Foot High-Speed Tunnel

Description: "An untwisted wing, which when unswept has an NACA 65-210 section, an aspect ratio of 9.0 and a taper ration of 2.5:1.0, has been tested with no sweep, and 30 deg and 45 deg of sweepback and sweepforward in conjunction with a typical fuselage at Mach numbers from 0.60 to 0.96 at angles of attack generally between -2 deg and 10 deg in the Langley 8-foot high-speed tunnel. Sweep was obtained by rotating the wing semispans about a point in the plane of symmetry. The normal-force, pitching-moment, … more
Date: February 14, 1947
Creator: Whitcomb, Richard T.
Partner: UNT Libraries Government Documents Department
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Aerodynamic Characteristics at High Speeds of Full-Scale Propellers Having Different Shank Designs

Description: "Tests of two 10-foot-diameter two-blade propellers which differed only in shank design have been made in the Langley 16-foot high-speed tunnel. The propellers are designated by their blade design numbers, NACA 10-(5)(08)-03, which had aerodynamically efficient airfoil shank sections, and NACA 10-(5)(08)-03R which had thick cylindrical shank sections typical of conventional blades. The propellers mere tested on a 2000-horsepower dynamometer through a range of blade-angles from 20 degrees to 55 … more
Date: February 13, 1947
Creator: Maynard, Julian D.
Partner: UNT Libraries Government Documents Department
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Comparison of Wind-Tunnel Predictions with Flight Measurements of the Longitudinal-Stability and -Control Characteristics of a Douglas BTD-1 Airplane

Description: "Low Mach number longitudinal-stability and control characteristics as predicted by use of wind tunnel data from a powered 3/16-scale model are compared with flight test measurements of a Navy BTD-1 airplane. The accuracy of the wind tunnel data and the discrepancies involved in attempting to correlate with flight data are discussed and analyzed. The comparison showed that wind tunnel predictions were, in general, in good agreement with flight test data" (p. 1).
Date: February 13, 1947
Creator: Bunnell, Mort V. & Delany, Noel K.
Partner: UNT Libraries Government Documents Department
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Full-Scale Investigation of the Maximum Lift and Flow Characteristics of an Airplane Having Approximately Triangular Plan Form

Description: Report discussing an investigation of the DM-1 glider, which has an approximately triangular plan form, with auxiliary studies of a model of triangular wings. The pitching-moment coefficient, drag coefficient, and angle of attack with the lift coefficient are provided. Results indicated that the angles of descent without power are likely to be prohibitive and airplanes with the tested type of wings will not be able to land safely without power.
Date: February 12, 1947
Creator: Wilson, Herbert A., Jr. & Lovell, J. Calvin
Partner: UNT Libraries Government Documents Department
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Investigation of Rim Cracking in Turbine Wheels with Welded Blades

Description: Rim cracking in turbine wheels with welded blades was evaluated. The problem is explained on the basis of the occurrence of plastic flow in the rim during transient starting conditions when thermal compressive stresses resulting from high-temperature gradients exceed the proportional elastic limit of the material.
Date: February 12, 1947
Creator: Millenson, M. B. & Manson, S. S.
Partner: UNT Libraries Government Documents Department
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Computed Temperature Distribution and Cooling of Solid Gas-Turbine Blades

Description: "Computations were made to determine the temperature distribution and cooling of solid gas-turbine blades.A range of temperatures was used from 1500 degrees to 2500 degrees F, blade-root temperatures from 100 degrees to 1000 degrees F, blade thermal conductivity from 8 to 220 BTU/(hr)(sq ft)(degrees F/ft), and net gas to metal heat transfer coefficients from 75 to 250 BTU/(hr)(sq ft)(degrees F)" (p. 1).
Date: February 11, 1947
Creator: Reuter, J. George & Gazley, Carl, Jr.
Partner: UNT Libraries Government Documents Department
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Cooling of Gas Turbines 1 - Effects of Addition of Fins to Blade Tips and Rotor, Admission of Cooling Air Through Part of Nozzles, and Change in Thermal Conductivity of Turbine Components

Description: "An analysis was developed for calculating the radial temperature distribution in a gas turbine with only the temperatures of the gas and the cooling air and the surface heat-transfer coefficient known. This analysis was applied to determine the temperatures of a complete wheel of a conventional single-stage impulse exhaust-gas turbine. The temperatures were first calculated for the case of the turbine operating at design conditions of speed, gas flow, etc. and with only the customary cooling a… more
Date: February 11, 1947
Creator: Brown, W. Byron
Partner: UNT Libraries Government Documents Department
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Cooling of Gas Turbines, 3, Analysis of Rotor and Blade Temperatures in Liquid-Cooled Gas Turbines

Description: A theoretical analysis of the radial temperature distribution through the rotor and constant cross sectional area blades near the coolant passages of liquid cooled gas turbines was made. The analysis was applied to obtain the rotor and blade temperatures of a specific turbine using a gas flow of 55 pounds per second, a coolant flow of 6.42 pounds per second, and an average coolant temperature of 200 degrees F. The effect of using kerosene, water, and ethylene glycol was determined. The effect … more
Date: February 11, 1947
Creator: Brown, W. Byron & Livingood, John N. B.
Partner: UNT Libraries Government Documents Department
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Development of Inboard Nacelle for the XB-36 Airplane

Description: From Summary: "A series of investigations of several 1/14-scale models of an inboard nacelle for the XB-36 airplane was made in the Langley two-dimensional low-turbulence tunnels. The purpose of these investigations was to develop a low-drag wing-nacelle pusher combination which incorporated an internal air-flow system. As a result of these investigations, a nacelle was developed which had external drag coefficients considerably lower than the original basic form with the external nacelle drag … more
Date: February 11, 1947
Creator: Nuber, Robert J.
Partner: UNT Libraries Government Documents Department
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Investigation of Pressure Losses in Several Turbosupercharger Nozzle Hoses

Description: Memorandum presenting surveys of the impact pressure of the flow to obtain information for determining pressure losses in four different turbosupercharger nozzle boxes. The data indicated substantial differences in total head loss among the boxes and the existence of sharply defined high-loss regions in portions of the nozzle annulus.
Date: February 11, 1947
Creator: Lord, Albert M. & Donnola, Joseph
Partner: UNT Libraries Government Documents Department
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Theoretical Evaluation of Methods of Cooling the Blades of Gas Turbines

Description: A study was made of heat transfer in turbine blades and the effects on blade temperature of cooling the blade root and tip, changing the dimensions of the blades, raising the cycle temperatures, insulating with ceramics, and cooling by circulation of air or water through hollow blades. The results indicated that cooling of the root of the blade, shortening the blade, and cooling hollow blades internally with air or liquid offer possibilities of substantial increases in permissible gas temperatu… more
Date: February 11, 1947
Creator: Sanders, J. C. & Mendelson, Alexander
Partner: UNT Libraries Government Documents Department
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Analytical Comparison of a Standard Turbojet Engine, a Turbojet Engine with a Tail-Pipe Burner, and a Ram-Jet Engine

Description: From Introduction: "Experimental investigations (reference 1) have shown that in some cases the thrust can be more than doubled by means of tail-pipe burning. A comparison is made of a standard turbojet engine, whose thrust is augmented by tail-pipe burning, and a ram-jet engine. The performance characteristics for the ram-jet engine were computed entirely from theoretical considerations and on the assumption that the burner-inlet velocity was constant."
Date: February 10, 1947
Creator: Krebs, Richard P. & Palasics, John
Partner: UNT Libraries Government Documents Department
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