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Determination of ground effect from tests of a glider in towed flight

Description: Report presents the results of an investigation made to find the effect of ground on the aerodynamic characteristics of a Franklin PS-2 glider. The lift, the drag, and the angle of attack of the glider in towed flight were determined at several heights from 0.14 to 1.19 span lengths and at various speeds for each height. Two wing arrangements were tested: the plain wing, and the wing with a nearly full-span 30-percent-chord split flap deflected 45 degrees. The experimental results for the plain… more
Date: April 8, 1940
Creator: Wetmore, J. W. & Turner, L. I., Jr.
Item Type: Refine your search to only Report
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Mechanism of flutter: A theoretical and experimental investigation of the flutter problem

Description: From Summary: "The results of the basic flutter theory originally devised in 1934 and published as NACA Technical Report no. 496 are presented in a simpler and more complete form convenient for further studies. The paper attempts to facilitate the judgement of flutter problems by a systematic survey of the theoretical effects of the various parameters. A large number of experiments were conducted on cantilever wings, with and without ailerons, in the NACA high-speed wind tunnel for the purpose … more
Date: September 22, 1938
Creator: Theodorsen, Theodore & Garrick, I. E.
Item Type: Refine your search to only Report
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Stability of Castering Wheels for Aircraft Landing Gears

Description: "A theoretical study was made of the shimmy of castering wheels. The theory is based on the discovery of a phenomenon called kinematic shimmy. Experimental checks, use being made of a model having low-pressure tires, are reported and the applicability of the results to full scale is discussed. Theoretical methods of estimating the spindle viscous damping and the spindle solid friction necessary to avoid shimmy are given. A new method of avoiding shimmy -- lateral freedom -- is introduced" (p. 1… more
Date: August 11, 1937
Creator: Kantrowitz, Arthur
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
open access

Tests in the variable-density wind tunnel of the NACA 23012 airfoil with plain and split flaps

Description: From Summary: "Section characteristics for use in wing design are presented for the NACA 23012 airfoil with plain and split flaps of 20 percent wing chord at a value of the effective Reynolds number of about 8,000,000. The flap deflections covered a range from 60 degrees upward to 75 degrees downward for the plain flap and from neutral to 90 degrees downward for the split flap. The split flap was aerodynamically superior to the plain flap in producing high maximum lift coefficients and in havin… more
Date: January 21, 1938
Creator: Abbott, Ira H. & Greenberg, Harry
Item Type: Refine your search to only Report
open access

Design of NACA Cowlings for Radial Air-Cooled Engines

Description: "The information on the propeller-cowling-nacelle combinations, presented in Technical Reports nos. 592, 593, and 596 and in Technical Note 620, is applied to the practical design of NACA cowlings. The main emphasis is placed on the method of obtaining the dimensions of the cowling; consequently, the physical functioning of each part of the cowling is treated very briefly. A practical method of designing cowlings and some examples are presented" (p. 383).
Date: March 5, 1938
Creator: Stickle, George W.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
open access

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.
Item Type: Refine your search to only Report
open access

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.
Item Type: Refine your search to only Report
open access

Static Thrust and Power Characteristics of Six Full-Scale Propellers

Description: "Static thrust and power measurements were made of six full-scale propellers. The propellers were mounted in front of a liquid-cooled-engine nacelle and were tested at 15 different blade angles in the range from -7 1/2 degrees to 35 degrees at 0.75r. The test rig was located outdoors and the tests were made under conditions of approximately zero wind velocity" (p. 85).
Date: January 25, 1939
Creator: Hartman, Edwin P. & Biermann, David
Item Type: Refine your search to only Report
open access

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.
Item Type: Refine your search to only Report
open access

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.
Item Type: Refine your search to only Report
open access

Preliminary investigation of the flying qualities of airplanes

Description: "The National Advisory Committee for Aeronautics is undertaking an investigation of the flying qualities of airplanes. The work consists in the determination of the significant qualities susceptible of measurement, the development of the instruments required to make the measurements, and the accumulation of data on the flying qualities of existing airplanes, which data are to serve as a basis for quantitative specifications for the flying qualities of future designs" (p. 449).
Date: March 29, 1940
Creator: Soulé, H. A.
Item Type: Refine your search to only Report
open access

Pressure available for cooling with cowling flaps

Description: Report presents the results of a full-scale investigation conducted in the NACA 20-foot tunnel to determine the pressure difference available for cooling with cowling flaps. The flaps were applied to an exit slot of smooth contour at 0 degree flap angle. Flap angles of 0 degree, 15 degrees, and 30 degrees were tested. Two propellers were used; propeller c which has conventional round blade shanks and propeller f which has airfoil sections extending closer to the hub. The pressure available for … more
Date: May 9, 1940
Creator: Stickle, George W.; Naiman, Irven & Crigler, John L.
Item Type: Refine your search to only Report
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A simplified theoretical method of determining the characteristics of a lifting rotor in forward flight

Description: Theoretical derived expressions for the flapping, the thrust, the torque, and the profile drag-lift ratio of nonfeathering rotor with hinged, rectangular, linearly twisted blades are given as simple functions of the inflow velocity and the blade pitch. Representative values of the coefficients of each of the terms in these expressions are tabulated for a series of specified values of the tip-speed ratio. Analysis indicates that the tabulated values can be used to calculate, with reasonable accu… more
Date: March 17, 1941
Creator: Bailey, F. J., Jr.
Item Type: Refine your search to only Report
open access

Flow coefficients of monosleeve valves

Description: The flow coefficients of the intake and the exhaust ports of a sleeve-valve cylinder were measured by attaching the cylinder to a large tank and measuring the changes in pressure and temperature in the tank that were caused by short periods of air flow through the valve ports. The derivation of the equations on which the flow coefficients are based is given. The distribution of total pressure in the arms of the sleeve-valve intake manifold was measured. The arms are found to have as little as 7… more
Date: February 8, 1940
Creator: Waldron, C. D.
Item Type: Refine your search to only Report
open access

Downwash and Wake Behind Plain and Flapped Airfoils

Description: "Extensive experimental measurements have been made of the downwash angles and the wake characteristics behind airfoils with and without flaps and the data have been analyzed and correlated with the theory. A detailed study was made of the errors involved in applying lifting-line theory, such as the effects of a finite wing chord, the rolling-up of the trailing vortex sheet, and the wake. The downwash angles, as computed from the theoretical span load distribution by means of the Biot-Savart eq… more
Date: June 23, 1938
Creator: Silverstein, Abe; Katzoff, S. & Bullivant, W. Kenneth
Item Type: Refine your search to only Report
open access

Air Flow in the Boundary Layer of an Elliptic Cylinder

Description: From Introduction: "The present investigation was carried out for the purpose of supplementing the earlier work with information on the boundary layer under such conditions of air speed and turbulence that transition occurs and the layer is partly laminar and partly turbulent. In the work reported in reference 1, the air speed was about 12 feet per second, and it was assumed that the boundary layer remained in the laminar condition until after separation because the separation point remained fi… more
Date: August 6, 1938
Creator: Schubauer, G. B.
Item Type: Refine your search to only Report
open access

Pressure distribution over NACA 23012 airfoil with a slotted and a split flap

Description: A pressure-distribution investigation has been conducted in the NACA 4 by 6-foot vertical wind tunnel to determine the air loads on an NACA 23012 airfoil in combination with a 25.66-percent-chord slotted flap and a 20-percent-chord split flap. Pressures were measured on both the upper and the lower surfaces of the main airfoil and the flaps for several angles of attack and at several flap settings. The data, presented as pressure diagrams and as graphs of the section coefficients for the flap a… more
Date: May 28, 1940
Creator: Harris, Thomas A. & Lowry, John G.
Item Type: Refine your search to only Report
open access

The problem of cooling an air-cooled cylinder on an aircraft engine

Description: An analysis of the cooling problem has been to show by what means the cooling of an air-cooled aircraft engine may be improved. Each means of improving cooling is analyzed on the basis of effectiveness in cooling with respect to power for cooling. The altitude problem is analyzed for both supercharged and unsupercharged engines. The case of ground cooling is also discussed. The heat-transfer process from the hot gases to the cylinder wall is discussed on the basis of the fundamentals of heat tr… more
Date: April 22, 1940
Creator: Brevoort, M. J. & Joyner, U. T.
Item Type: Refine your search to only Report
open access

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.
Item Type: Refine your search to only Report
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