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Barnyard Manure.

Description: Describes the benefits of more economical management of organic farm resources, namely barnyard manure. Discusses the management and application of methods for using fertilizers on the farm.
Date: May 10, 1906
Creator: United States. Department of Agriculture.
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Effect of variation of chord and span of ailerons on rolling and yawing moments in level flight

Description: This report presents the results of an investigation of the rolling and yawing moments due to ailerons of various chords and spans on two airfoils having the Clark Y and U. S. A. 27 wing sections. Some attention is devoted to a study of the effect of scale on rolling and yawing moments and to the effect of slightly rounding the wing tips. The results apply to level flight with the wing chord set at an angle of attack of +4 degrees and to conditions of zero pitch, zero yaw, and zero roll of the … more
Date: July 10, 1928
Creator: Heald, R. H. & Strother, D. H.
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Full-scale wind-tunnel tests of a propeller with the diameter changed by cutting off the blade tips

Description: Tests were conducted in order to determine how the characteristics of a propeller are affected by cutting off the tips. The diameter of a standard 10-foot metal propeller was changed successively to 9 feet 6 inches, 9 feet 0 inches, 8 feet 6 inches, and 8 feet 0 inches. Each propeller thus formed was tested at four pitch settings using an open cockpit fuselage and a D-12 engine. A small loss in propulsive efficiency is indicated. Examples are given showing the application of the results to prac… more
Date: December 10, 1929
Creator: Wood, Donald H.
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Wind-Tunnel Research Comparing Lateral Control Devices, Particularly at High Angles of Attack 1: Ordinary Ailerons on Rectangular Wings

Description: "This report is the first in a series in which it is intended to compare the relative merits of all ordinary and some special forms of ailerons and other lateral control devices in regard to their effect on lateral controllability, lateral stability, and airplane performance. The comparisons are based on wind-tunnel test data, all the control devices being fitted to model wings having the same span, area, and airfoil section, and being subjected to the same series of force and rotation tests. T… more
Date: December 10, 1931
Creator: Weick, Fred E. & Wenzinger, Carl J.
open access

Increasing the air charge and scavenging the clearance volume of a compression-ignition engine

Description: The object of the investigation presented in this report was to determine the effects of increasing the air charge and scavenging the clearance volume of a 4-stroke-cycle compression-ignition engine having a vertical-disk form combustion chamber. Boosting the inlet-air pressure with normal valve timing increased the indicated engine power in proportion to the additional air inducted and resulted in smoother engine operation with less combustion shock. Scavenging the clearance volume by using a … more
Date: June 10, 1933
Creator: Spanogle, J. A.; Hicks, C. W. & Foster, H. H.
open access

Strength Tests of Thin-Walled Duralumin Cylinders in Compression

Description: "This report is the second of a series presenting the results of strength tests of thin-walled duralumin cylinders and truncated cones of circular and elliptic section. It contains the results obtained from compression tests on 45 thin-walled duralumin cylinders of circular section with ends clamped to rigid bulkheads. In addition to the tests on duralumin cylinders, there are included the results of numerous tests on rubber, celluloid, steel, and brass cylinders obtained from various sources" … more
Date: June 10, 1933
Creator: Lundquist, Eugene E.
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Wind-Tunnel Tests on Combinations of a Wing With Fixed Auxiliary Airfoils Having Various Chords and Profiles

Description: This report presents the results of wind tunnel tests on various auxiliary airfoils having three different airfoil sections and several different chord lengths in combination with a Clark Y model wing in a sufficient number of relative positions to determine the optimum with regard to certain criterions of aerodynamic performance. The airfoil sections included a symmetrical profile, one of medium camber, and a highly cambered one. The chord sizes of the auxiliary airfoils ranged from 7.5 to 25 … more
Date: June 10, 1933
Creator: Weick, Fred E. & Sanders, Robert
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A Flight Investigation of the Effect of Mass Distribution and Control Setting on the Spinning of the XN2Y-1 Airplane

Description: "The investigation of the effect of mass distribution on the spinning of airplanes initiated with tests on the NY-1 airplane has been continued by tests on another airplane in order to increase the scope of the information and to observe particularly the behavior of an airplane that shows considerable change in sideslip angle for its various conditions of spinning. The XN2Y-1 naval training biplane was used for the present tests in which changes of ballast along the longitudinal and lateral axe… more
Date: January 10, 1934
Creator: Scudder, N. F.
open access

Analysis of 2-Spar Cantilever Wings With Special Reference to Torsion and Load Transference

Description: "This paper deals with the analysis of 2-spar cantilever wings in torsion, taking cognizance of the fact that the spars are not independent, but are interconnected by ribs and other structural members. The principles of interaction are briefly explained, showing that the mutual relief action occurring depends on the "pure torsional stiffness" of the wing cross section. Various practical methods of analysis are outlined" (p. 45).
Date: April 10, 1934
Creator: Kuhn, Paul
open access

Vibration response of airplane structures

Description: This report presents test results of experiments on the vibration-response characteristics of airplane structures on the ground and in flight. It also gives details regarding the construction and operation of vibration instruments developed by the National Advisory Committee for Aeronautics.
Date: May 10, 1934
Creator: Theodorsen, Theodore & Gelalles, A. G.
open access

General equations for the stress analysis of rings

Description: In this report it is shown that the shear, axial force, and moment at one point in a simple ring subjected to any loading condition can be given by three independent equations involving certain integrals that must be evaluated regardless of the method of analysis used. It is also shown how symmetry of the ring alone or of the ring and the loading about 1 or 2 axes makes it possible to simplify the three equations and greatly reduces the number of integrals that must be evaluated. Application of… more
Date: August 10, 1934
Creator: Lundquist, Eugene E. & Burke, Walter F.
open access

Experimental investigation of the Robinson-type cup anemometer

Description: This report presents the results of wind tunnel tests on a Robinson-type anemometer. The investigation covered force measurements on individual cups, as well as static and dynamic torque measurements and calibrations on complete cup wheels. In the tests on individual cups 5 cup forms were used and in the measurements on complete cup wheels 4 cup wheels with 3 arm lengths for each cup wheel were tested. All the results are presented in graphical form.
Date: October 10, 1934
Creator: Brevoort, M. J. & Joyner, U. T.
open access

The Effect of Water Vapor on Flame Velocity in Equivalent Carbon Monoxide and Oxygen Mixtures

Description: This report presents the results of an investigation to study the effect of water vapor upon the spatial speed of flame in equivalent mixtures of carbon monoxide and oxygen at various total pressures from 100 to 780 mm.hg. These results show that, within this pressure range, an increase in flame speed is produced by increasing the mole fraction of water vapor at least as far as saturation at 25 degrees c., and that the rate of this increase is greater the higher the pressure. It is evident that… more
Date: January 10, 1935
Creator: Fiock, Ernest F. & King, H. Kendall
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The Soap-Bubble Method of Studying the Combustion of Mixtures of Carbon Monoxide and Oxygen

Description: This investigation is a detailed description of the soap-bubble, or constant-pressure, method as applied to the explosive oxidation of carbon monoxide. A series of values of the speed of flame in space in various mixtures of CO and O2 containing a constant percentage of water vapor was obtained by the constant-volume method. These results served as a guide in the perfection of the soap-bubble method.
Date: January 10, 1935
Creator: Fiock, Ernest F. & Roeder, Carl H.
open access

Investigation of Full-Scale Split Trailing-Edge Wing Flaps With Various Chords and Hinge Locations

Description: This report gives the results of an investigation conducted in the NACA full-scale wind tunnel on a small parasol monoplane equipped with three different split trailing-edge wing flaps. The object of the investigation was to determine and correlate data on the characteristics of the airplane and flaps as affected by variation in flap chord, flap deflection, and flap location along the wing chord. The results give the lift, the drag, and the pitching moment characteristics of the airplane, and t… more
Date: May 10, 1935
Creator: Wallace, Rudolf
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A study of the torque equilibrium of an autogiro rotor

Description: From Summary: "Two improvements have been made in the method developed in NACA Reports nos. 487 and 591 for the estimation of the inflow velocity required to overcome a given decelerating torque in an autogiro rotor. At low tip-speed ratios, where the assumptions necessary for the analytical integrations of the earlier papers are valid, the expressions therein derived are greatly simplified by combining and eliminating terms with a view of minimizing the numerical computations required. At high… more
Date: January 10, 1938
Creator: Bailey, F. J., Jr.
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The influence of directed air flow on combustion in spark-ignition engine

Description: "The air movement within the cylinder of the NACA combustion apparatus was regulated by using shrouded inlet valves and by fairing the inlet passage. Rates of combustion were determined at different inlet-air velocities with the engine speed maintained constant and at different engine speeds with the inlet-air velocity maintained approximately constant. The rate of combustion increased when the engine speed was doubled without changing the inlet-air velocity; the observed increase was about the… more
Date: October 10, 1938
Creator: Rothrock, A. M. & Spencer, R. C.
open access

Preliminary wind-tunnel investigation of an NACA 23012 airfoil with various arrangements of venetian-blind flaps

Description: Report presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of a large-chord NACA 23012 airfoil with several arrangements of venetian-blind flaps to determine the aerodynamic section characteristics as affected by the over-all flap chord, the chords of the slats used to form the flap, the slat spacing, the number of slats and the position of the flap with respect to the wing. Complete section data are given in the form of graphs for all the combinations tested.
Date: January 10, 1939
Creator: Wenzinger, Carl J. & Harris, Thomas A.
open access

Wind-tunnel investigation of NACA 23012, 23021, and 23030 airfoils with various sizes of split flap

Description: Report presents the results of an investigation made in the NACA 7 by 10-foot wind tunnel of large-chord NACA and 23021, and 23030 airfoils with split flaps 10, 20, 30, and 40 percent of the wing chord to determine the section aerodynamic characteristics of the airfoils as affected by airfoil thickness, flap chord, and flap deflection. The complete section aerodynamic characteristics of all the combinations tested are given in the form of graphs of lift, drag, and pitching-moment coefficients, … more
Date: March 10, 1939
Creator: Wenzinger, Carl J. & Harris, Thomas A.
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Heat treating and inspection of metals

Description: This report discusses these topics: I. Principles of heat treating -- II. Heat-treating equipment -- III. General heat treatment of steel -- IV. Specific heat treatments for aircraft steels -- V. General heat treatment of aluminum alloys -- VII. Hardness testing -- VIII. Magnaflux inspection.
Date: September 10, 1941
Creator: United States. War Department.
open access

Normal-pressure tests of circular plates with clamped edges

Description: A fixture is described for making normal-pressure tests of flat plates 5 inches in diameter in which particular care was taken to obtain rigid clamping at the edges. Results are given for 19 plates, ranging in thickness form 0.015 to 0.072 inch. The center deflections and the extreme-fiber stresses at low pressures were found to agree with theoretical values; the center deflections at high pressures were 4 to 12 percent greater than the theoretical values. Empirical curves are derived of the pr… more
Date: October 10, 1941
Creator: McPherson, Albert E.; Ramberg, Walter & Levy, Samuel
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