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The aerodynamic characteristics of six full-scale propellers having different airfoil sections

Description: From Summary: "Wind-tunnel tests are reported of six 3-blade 10-foot propellers operated in front of a liquid-cooled engine nacelle. The propellers were identical except for blade airfoil sections, which were: Clark y, R.A.F. 6, NACA 4400, NACA 2400-34, NACA 2rsub200, and NACA 6400. The range of blade angles investigated extended for 15 degrees to 40 degrees for all propellers except the Clark y, for which it extended to 45 degrees. The results showed that the range in maximum efficiency betwee… more
Date: 1939
Creator: Biermann, David & Hartman, Edwin P.
Partner: UNT Libraries Government Documents Department
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Aircraft rate-of-climb indicators

Description: From Summary: "The theory of the rate-of-climb indicator is developed in a form adapted for application to the instrument in its present-day form. Certain dynamic effects, including instrument lag, and the use of the rate-of-climb indicator as a statoscope are also considered. Modern instruments are described. A laboratory test procedure is outlined and test results are given."
Date: 1939
Creator: Johnson, Daniel P.
Partner: UNT Libraries Government Documents Department
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Airfoil section characteristics as affected by variations of the Reynolds number

Description: Report presents the results of an investigation of a systematically chosen representative group of related airfoils conducted in the NACA variable-density wind tunnel over a wide range of Reynolds number extending well into the flight range. The tests were made to provide information from which the variations of airfoil section characteristics with changes in the Reynolds number could be inferred and methods of allowing for these variations in practice could be determined. This work is one phas… more
Date: 1939
Creator: Jacobs, Eastman N. & Sherman, Albert
Partner: UNT Libraries Government Documents Department
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Airfoil section data obtained in the NACA variable-density tunnel as affected by support interference and other corrections

Description: From Introduction: "The purpose of this report is to present the corrections for application to published results from the variable-density tunnel to give more reliable values of section profile-drag coefficient for airfoils of various thickness."
Date: 1939
Creator: Jacobs, Eastman N. & Abbott, Ira H.
Partner: UNT Libraries Government Documents Department
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Calculation of the Aerodynamic Characteristics of Tapered Wings With Partial-Span Flaps

Description: "Factors derived from wing theory are presented. By means of these factors, the angle of zero lift, the lift-curve slope, the pitching moment, the aerodynamic-center position, and the induced drag of tapered wings with partial-span flaps may be calculated. The factors are given for wings of aspect ratios 6 and 10 , of taper ratios from 0.25 to 1.00, and with flaps of various length. An example is presented of the method of application of the factors. Fair agreement with experimental results is … more
Date: January 23, 1939
Creator: Pearson, Henry A. & Anderson, Raymond F.
Partner: UNT Libraries Government Documents Department
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Cooling on the front of an air-cooled engine cylinder in a conventional engine cowling

Description: Measurements were made of the cooling on the fronts of model cylinders in a conventional cowling for cooling in both the ground and the cruising conditions. The mechanisms of front and rear cooling are essentially different. Cooling on the rear baffled part of the cylinders continually increases with increasing fin width. For the front of the cylinder, an optimum fin width was found to exist beyond which an increase in width reduced the heat transfer. The heat transfer coefficient on the front … more
Date: April 5, 1939
Creator: Brevoort, M. J. & Joyner, U. T.
Partner: UNT Libraries Government Documents Department
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Correlation of Cooling Data From an Air-Cooled Cylinder and Several Multicylinder Engines

Description: "The theory of engine-cylinder cooling developed in a previous report was further substantiated by data obtained on a cylinder from a Wright R-1820-G engine. Equations are presented for the average head and barrel temperatures of this cylinder as functions of the engine and the cooling conditions. These equations are utilized to calculate the variation in cylinder temperature with altitude for level flight and climb" (p. 59).
Date: August 15, 1939
Creator: Pinkel, Benjamin & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
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The design of fins for air-cooled cylinders

Description: From Summary: "An analysis was made to determine the proportions of fins made of aluminum, copper, magnesium, and steel necessary to dissipate maximum quantities of heat for different fin widths, fin weights, and air-flow conditions. The analysis also concerns the determination of the optimum fin proportions when specified limits are placed on the fin dimensions. The calculation of the heat flow in the fins is based on experimentally verified, theoretical equations. The surface heat-transfer co… more
Date: June 28, 1939
Creator: Biermann, Arnold E. & Ellerbrock, Herman H., Jr.
Partner: UNT Libraries Government Documents Department
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Determination of the Profile Drag of an Airplane Wing in Flight at High Reynolds Numbers

Description: Report presenting flight tests to determine the profile-drag coefficients of a portion of the original wing surface of an all-metal airplane and a portion of the wing made aerodynamically smooth and more nearly fair than the original section. Tests were also carried out to determine the point of transition from laminar to turbulent boundary layer and to determine the velocity distribution along the upper surface of the wing.
Date: 1939
Creator: Bicknell, Joseph
Partner: UNT Libraries Government Documents Department
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Determination of the Profile Drag of an Airplane Wing in Flight at High Reynolds Numbers

Description: "Flight tests were made to determine the profile-drag coefficients of a portion of the original wing surface of an all-metal airplane and of a portion of the wing made aerodynamically smooth and more nearly fair than the original section. The wing section was approximately the NACA 2414.5. The tests were carried out over a range of airplane speeds giving a maximum Reynolds number of 15,000,000. Tests were also carried out to locate the point of transition from laminar to turbulent boundary laye… more
Date: January 6, 1939
Creator: Bicknell, Joseph
Partner: UNT Libraries Government Documents Department
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Effect of exit-slot position and opening on the available cooling pressure for NACA nose-slot cowlings

Description: Report presents the results of an investigation of full-scale nose-slot cowlings conducted in the NACA 20-foot wind tunnel to furnish information on the pressure drop available for cooling. Engine conductances from 0 to 0.12 and exit-slot conductances from 0 to 0.30 were covered. Two basic nose shapes were tested to determine the effect of the radius of curvature of the nose contour; the nose shape with the smaller radius of curvature gave the higher pressure drop across the engine. The best ax… more
Date: January 18, 1939
Creator: Stickle, George W.; Naiman, Irven & Crigler, John L.
Partner: UNT Libraries Government Documents Department
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Effect of fuel-air ratio, inlet temperature, and exhaust pressure on detonation

Description: From Summary: "An accurate determination of the end-gas condition was attempted by applying a refined method of analysis to experimental results. The results are compared with those obtained in Technical Report no. 655. The experimental technique employed afforded excellent control over the engine variables and unusual cyclic reproducibility. This, in conjunction with the new analysis, made possible the determination of the state of the end-gas at any instant to a fair degree of precision. Resu… more
Date: November 15, 1939
Creator: Taylor, E. S.; Leary, W. A. & Diver, J. R.
Partner: UNT Libraries Government Documents Department
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The effect of nacelle-propeller diameter ratio on body interference and on propeller and cooling characteristics

Description: Report presents the results of an investigation conducted in the NACA 20-foot tunnel to determine the slipstream drag, the body interference, and the cooling characteristics of nacelle-propeller diameter. Four combinations of geometrically similar propellers and nacelles, mounted on standard wing supports, were tested with values of the ratio of nacelle diameter to propeller diameter of 0.25, 0.33, and 0.44.
Date: April 17, 1939
Creator: McHugh, James G. & Derring, Eldridge H.
Partner: UNT Libraries Government Documents Department
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Effect of Service Stress on Impact Resistance, X-Ray Diffraction Patterns, and Microstructure of 25S Aluminum Alloy

Description: Report presents the results of a great number of tests made to determine the effect of service stresses on the impact resistance, the x-ray diffraction patterns, and the microstructure of 25s aluminum alloy. Many of the specimens were taken from actual propeller blades and others were cut from 13/16-inch rod furnished by the Aluminum Company of America.
Date: 1939
Creator: Kies, J. A. & Quick, G. W.
Partner: UNT Libraries Government Documents Department
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Effective Gust Structure at Low Altitudes as Determined From the Reactions of an Airplane

Description: "Measurements of gust structure and gust intensity were made in the lower levels of the atmosphere (0 to 3,500 ft.). An Aeronca C-2 airplane was used as the measuring instrument, the gust structure being derived from the recorded motions of the airplane. Data were also obtained on wind velocities and temperatures as functions of altitude for use in attempting to correlate the gust-structure data with various meteorological quantities" (p. 263).
Date: October 19, 1939
Creator: Donely, Philip
Partner: UNT Libraries Government Documents Department
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Effects of elevator nose shape, gap, balance, and tabs on the aerodynamic characteristics of a horizontal tail surface

Description: Results are presented showing the effects of gap, elevator, nose shape, balance, cut-out, and tabs on the aerodynamic characteristics of a horizontal tail surface tested in the NACA full-scale tunnel.
Date: April 27, 1939
Creator: Goett, Harry J. & Reeder, J. P.
Partner: UNT Libraries Government Documents Department
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Experimental Investigation of the Momentum Method for Determining Profile Drag

Description: Report presents the results of an experimental investigation conducted in the full-scale tunnel to determine the accuracy of the Jones and the Betz equations for computing profile drag from total and static pressure surveys in the wake of wings. Surveys were made behind 6 by 8-foot airfoils of the NACA 0009, and 0018 sections at zero lift and behind the NACA 0012 at positive lifts. The surveys were made at various spanwise positions and at distances behind the airfoil ranging from 0.05c to 3.00… more
Date: 1939
Creator: Goett, Harry J.
Partner: UNT Libraries Government Documents Department
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Experimental Verification of the Theory of Oscillating Airfoils

Description: "Measurements have been made of the lift on an airfoil in pitching oscillation with a continuous-recording, instantaneous-force balance. The experimental values for the phase difference between the angle of attack and the lift are shown to be in close agreement with theory" (p. 619).
Date: April 24, 1939
Creator: Silverstein, Abe & Joyner, Upshur T.
Partner: UNT Libraries Government Documents Department
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Flame Speeds and Energy Considerations for Explosions in a Spherical Bomb

Description: "Simultaneous measurements were made of the speed of flame and the rise in pressure during explosions of mixtures of carbon monoxide, normal heptane, iso-octane, and benzene in a 10-inch spherical bomb with central ignition. From these records, fundamental properties of the explosive mixtures, which are independent of the apparatus, were computed. The transformation velocity, or speed at which flame advances into and transforms the explosive mixture, increases with both the temperature and the … more
Date: September 28, 1939
Creator: Fiock, Ernest F.; Marvin, Charles F., Jr.; Caldwell, Frank R. & Roeder, Carl H.
Partner: UNT Libraries Government Documents Department
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Free-spinning wind-tunnel tests of a low-wing monoplane with systematic changes in wings and tails IV: effect of center-of-gravity location

Description: Eight wings and three tails, covering a wide range of aerodynamic characteristics, were independently ballasted so as to be interchangeable with no change in mass distribution. For each of the 24 resulting wing-tail combinations, observations were made of the steady spin for four control settings and of recoveries for five control manipulations. The results are presented in the form of charts comparing the spin characteristics. The tests are part of a general investigation being made in the NAC… more
Date: March 28, 1939
Creator: Seidman, Oscar & Neihouse, A. I.
Partner: UNT Libraries Government Documents Department
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High-Speed Tests of Conventional Radial-Engine Cowlings

Description: The drag characteristics of eight radial-engine cowlings have been determined over a wide speed range in the NACA 8-foot high-speed wind tunnel. The pressure distribution over all cowlings was measured, to and above the speed of the compressibility burble, as an aid in interpreting the force tests. One-fifth-scale models of radial-engine cowlings on a wing-nacelle combination were used in the tests.
Date: March 30, 1939
Creator: Robinson, Russell G. & Becker, John V.
Partner: UNT Libraries Government Documents Department
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An investigation of the drag of windshields in the 8-foot high-speed wind tunnel

Description: Report presents the results of tests made to determine the drag of closed-cockpit and transport-type windshields. The tests were made at speeds corresponding to a Mach number range of approximately 0.25 to 0.58 in the NACA 8-foot high-speed wind tunnel. This speed range corresponds to a test Reynolds number range of 2,510,000 to 4,830,000 based on the mean aerodynamic chord of the full-span model (17.29 in.). The shapes of the windshield proper, the hood, and the tail fairing were systematicall… more
Date: May 22, 1939
Creator: Robinson, Russell G. & Delano, James B.
Partner: UNT Libraries Government Documents Department
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Longitudinal Stability and Control With Special Reference to Slipstream Effects

Description: Report presents the results of a study of data obtained in the NACA full-scale wind tunnel concerning the effects of interference and of propeller operation on longitudinal stability and control. The data include pitching moments for various power conditions for airplanes with tails removed and with tails set at various stabilizer and elevator angles. A number of surveys of the dynamic pressure and the flow direction in the region of the horizontal tail surface are also included.
Date: August 24, 1939
Creator: Katzoff, S.
Partner: UNT Libraries Government Documents Department
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