National Advisory Committee for Aeronautics (NACA) - 359 Matching Results

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An analysis of the factors that determine the periodic twist of an autogiro rotor blade, with a comparison of predicted and measured results

Description: Report presents an analysis of the factors that determine the periodic twist of a rotor blade under the action of the air forces on it. The results of the analysis show that the Fourier coefficients of the twist are linear expressions involving only the tip-speed ratio, the pitch setting, the inflow coefficient, the pitching-moment coefficient of the blade airfoil section, and the physical characteristics of the rotor blade and machine.
Date: April 14, 1937
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Analytical and Experimental Study of the Effect of Periodic Blade Twist on the Thrust, Torque, and Flapping Motion of an Autogiro Rotor

Description: From Summary: "An analysis is made of the influence on autogiro rotor characteristics of a periodic blade twist that varies with the azimuth position of the rotor blade and the results are compared with experimental data. The analysis expresses the influence of this type of twist upon the thrust, torque, and flapping motion of the rotor. The check against experimental data shows that the periodic twist has a pronounced influence on the flapping motion and that this influence is accurately predi… more
Date: January 28, 1937
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Application of Practical Hydrodynamics to Airship Design

Description: The purpose of the first two parts of this report is to present in concise format all the formulas required for computation of the hydrodynamic forces, so that they can be easily computed for either straight or curvilinear flight. Improved approximations are also introduced having a high degree of accuracy throughout the entire range of practical proportions. The remaining two parts of the report are devoted respectively to stability and skin friction, as functions of the same hydrodynamic forc… more
Date: 1933
Creator: Upson, Ralph H. & Klikoff, W. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Approximate Stress Analysis of Multistringer Beams With Shear Deformation of the Flanges

Description: "The problem of the skin-stringer combinations used as axially loaded panels or as covers for box beams is considered from the point of view of the practical stress analyst. By a simple substitution the problem is reduced to the problem of the single-stringer structure, which has been treated in NACA Report no. 608. The method of making this substitution is essentially empirical; in order to justify it, comparisons are shown between calculations and strain-gage tests of three beams tested by th… more
Date: April 20, 1938
Creator: Kuhn, Paul
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Auto-Ignition and Combustion of Diesel Fuel in a Constant-Volume Bomb

Description: Report presents the results of a study of variations in ignition lag and combustion associated with changes in air temperature and density for a diesel fuel in a constant-volume bomb. The test results have been discussed in terms of engine performance wherever comparisons could be drawn. The most important conclusions drawn from this investigation are: the ignition lag was essentially independent of the injected fuel quantity. Extrapolation of the curves for the fuel used shows that the lag cou… more
Date: October 5, 1937
Creator: Selden, Robert F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Automotive Ignition Coil

Description: This report gives the results of a series of measurements on the secondary voltage induced in an ignition coil of typical construction under a variety of operating conditions. These results show that the theoretical predictions hitherto made as to the behavior of this type of apparatus are in satisfactory agreement with the observed facts. The large mass of data obtained is here published both for the use of other investigators who may wish to compare them with other theoretical predictions and… more
Date: 1932%
Creator: Darnell, T. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Blower Cooling of Finned Cylinders

Description: "Several electrically heated finned steel cylinders enclosed in jackets were cooled by air from a blower. The effect of the air conditions and fin dimensions on the average surface heat-transfer coefficient q and the power required to force the air around the cylinders were determined. Tests were conducted at air velocities between the fins from 10 to 130 miles per hour and at specific weights of the air varying from 0.046 to 0.074 pound per cubic foot. The fin dimensions of the cylinders cover… more
Date: November 14, 1936
Creator: Schey, Oscar W. & Ellerbrock, Herman H., Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calculated and measured pressure distributions over the midspan section of the NACA 4412 airfoil

Description: Pressures were simultaneously measured in the variable-density tunnel at 54 orifices distributed over the midspan section of 5 by 30 inch rectangular model of the NACA 4412 airfoil at 17 angles of attack ranging from -20 degrees to 30 degrees at a Reynolds number of approximately 3,000,000. Accurate data were thus obtained for studying the deviations of the results of potential-flow theory from measured results. The results of the analysis and a discussion of the experimental technique are pres… more
Date: March 25, 1936
Creator: Pinkerton, Robert M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The calculation of take-off run

Description: From Summary: "A comparatively simple method of calculating length of take-off run is developed from the assumption of a linear variation in net accelerating force with air speed and it is shown that the error involved is negligible. Detailed instructions are given for application of the formula and for the calculation of all factors involved."
Date: January 1934
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calculation of the chordwise load distribution over airfoil sections with plain, split, or serially hinged trailing-edge flaps

Description: From Summary: "A method is presented for the rapid calculation of the incremental chordwise normal-force distribution over an airfoil section due to the deflection of a plain flap or tab, a split flap, or a serially hinged flap. This report is intended as a supplement to NACA Report no. 631, wherein a method is presented for the calculation of the chordwise normal-force distribution over an airfoil without a flap or, as it may be considered, an airfoil with flap (or flaps) neutral. The method e… more
Date: 1938
Creator: Allen, H. Julian
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The characteristics of 78 related airfoil sections from tests in the variable-density wind tunnel

Description: An investigation of a large group of related airfoils was made in the NACA variable-density wind tunnel at a large value of the Reynolds number. The tests were made to provide data that may be directly employed for a rational choice of the most suitable airfoil section for a given application. The variation of the aerodynamic characteristics with variations in thickness and mean-line form were systematically studied. (author).
Date: December 20, 1932
Creator: Jacobs, Eastman N.; Ward, Kenneth E. & Pinkerton, Robert M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Characteristics of a Clark Y Wing Model Equipped With Several Forms of Low-Drag Fixed Slots

Description: This investigation was undertaken to develop a low-drag fixed slot for an airplane wing which would avoid the complications and maintenance difficulties of the present movable-type Handley Page slot. Tests were conducted on a series of fixed slots in an attempt to reduce the minimum drag coefficient without decreasing the maximum lift coefficient or the stalling angle of the slotted wing. The tests were made in the NACA 5-foot vertical wind tunnel on a Clark Y basic section having a 10-inch cho… more
Date: 1932
Creator: Weick, Fred E. & Wenzinger, Carl J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characteristics of Clark Y airfoils of small aspect ratios

Description: This report presents the results of a series of wind tunnel tests showing the force, moment, and autorotational characteristics of Clark Y airfoils having aspect ratios varying from 0.5 to 3. An airfoil of rectangular plan form was tested with rectangular tips, flared tips, and semicircular tips. Tests were also made on one airfoil of circular plan form and two airfoils of elliptical plan form. The tests revealed a marked delay of the stall and a decided increase in values of maximum lift coeff… more
Date: May 5, 1932
Creator: Zimmerman, C. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characteristics of six propellers including the high-speed range

Description: 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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Characteristics of the NACA 23012 airfoil from tests in the full-scale and variable-density tunnels

Description: "This report gives the results of tests in the NACA full-scale and variable-density tunnels of a new wing section, the NACA 23012, which is one of the more promising of an extended series of related airfoils recently developed. The tests were made at several values of the Reynolds number between 1,000,000 and 8,000,000. The new airfoil develops a reasonably high maximum lift and a low profile drag, which results in an unusually high value of the speed-range index. In addition, the pitching-mome… more
Date: March 1, 1935
Creator: Jacobs, Eastman N. & Clay, William C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Coefficients of discharge of fuel-injection nozzles for compression-ignition engines

Description: "This report presents the results of an investigation to determine the coefficients of discharge of nozzles with small, round orifices of the size used with high-speed compression-ignition engines. The injection pressures and chamber back pressures employed were comparable to those existing in compression-ignition engines during injection. The construction of the nozzles was varied to determine the effect of the nozzle design on the coefficient. Tests were also made with nozzles assembled in an… more
Date: September 11, 1930
Creator: Gelalles, A. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Collection of wind-tunnel data on commonly used wing sections

Description: This report groups in a uniform manner the aerodynamic properties of commonly used wing sections as determined from tests in various wind tunnels. The data have been collected from reports of a number of laboratories. Where necessary, transformation has been made to the absolute system of coefficients and tunnel wall interference corrections have been applied. Tables and graphs present the data in the various forms useful to the engineer in the selection of a wing section.
Date: January 1930
Creator: Louden, F. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Column Strength of Tubes Elastically Restrained Against Rotation at the Ends

Description: Report presents the results of a study made of the effects of known end restraint on commercially available round and streamline tubing of chromium-molybdenum steel, duralumin, stainless steel, and heat-treated chromium-molybdenum steel; and a more accurate method than any previously available, but still a practical method, was developed for designing compression members in riveted or welded structures, particularly aircraft. Two hundred specimens were tested as short, medium-length, and long c… more
Date: September 9, 1937
Creator: Osgood, William R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Column Strength of Two Extruded Aluminum-Alloy H-Sections

Description: "Extruded aluminum-alloy members of various cross sections are used in aircraft as compression members either singly or as stiffeners for aluminum-alloy sheet. In order to design such members, it is necessary to know their column strength or, in the case of stiffeners, the value of the double modulus, which is best obtained for practical purposes from column tests. Column tests made on two extruded h-sections are described, and column formulas and formulas for the ratio of the double modulus to… more
Date: September 30, 1938
Creator: Osgood, William R. & Holt, Marshall
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Combustion in a Bomb With a Fuel-Injection System

Description: "Fuel injected into a spherical bomb filled with air at a desired density and temperature could be ignited with a spark a few thousandths of a second after injection, an interval comparable with the ignition lag in fuel-injection engines. The effect of several variables on the extent and rate of combustion was investigated: time intervals between injection and ignition of fuel of 0.003 to 0.06 second and one of 5 minutes; initial air temperatures of 100 degrees C. to 250 degrees C.; initial air… more
Date: August 9, 1935
Creator: Cohn, Mildred & Spencer, Robert C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Combustion in a High-Speed Compression-Ignition Engine

Description: "An investigation conducted to determine the factors which control the combustion in a high-speed compression-ignition engine is presented. Indicator cards were taken with the Farnboro indicator and analyzed according to the tangent method devised by Schweitzer. The analysis show that in a quiescent combustion chamber increasing the time lag of auto-ignition increases the maximum rate of combustion. Increasing the maximum rate of combustion increases the tendency for detonation to occur" (p. 63… more
Date: May 21, 1931
Creator: Rothrock, A. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparative Flight and Full-Scale Wind-Tunnel Measurements of the Maximum Lift of an Airplane

Description: "Determinations of the power-off maximum lift of a Fairchild 22 airplane were made in the NACA full-scale wind tunnel and in flight. The results from the two types of test were in satisfactory agreement. It was found that, when the airplane was rotated positively in pitch through the angle of stall at rates of the order of 0.1 degree per second, the maximum lift coefficient was considerably higher than that obtained in the standard tests, in which the forces are measured with the angles of atta… more
Date: October 26, 1937
Creator: Silverstein, Abe; Katzoff, S. & Hootman, James A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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