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Aerodynamic theory and test of strut forms. Part I

Description: This report presents the first part of a two part study made under this title. In this part the symmetrical inviscid flow about an empirical strut of high service merit is found by both the Rankine and the Joukowsky methods. The results can be made to agree as closely as wished. Theoretical stream surfaces as well as surfaces of constant speed and pressure in the fluid about the strut are found. The surface pressure computed from the two theories agrees well with the measured pressure on the fo… more
Date: May 1928
Creator: Smith, R. H.
Item Type: Refine your search to only Report
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The prediction of airfoil characteristics

Description: This report describes and develops methods by which the aerodynamic characteristics of an airfoil may be calculated with sufficient accuracy for use in airplane design. These methods for prediction are based on the present aerodynamic theory and on empirical formulas derived from data obtained in the N. A. C. A. variable density wind tunnel at a Reynolds number corresponding approximately to full scale. (author).
Date: March 14, 1928
Creator: Higgins, George J.
Item Type: Refine your search to only Report
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Drag and Cooling With Various Forms of Cowling for A "Whirlwind" Radial Air-Cooled Engine - 1

Description: "This report presents the results of an investigation undertaken in the 20-foot Propeller Research Tunnel at Langley Field on the cowling of radial air-cooled engines. A portion of the investigation has been completed, in which several forms and degrees of cowling were tested on Wright "Whirlwind" J-5 engine mounted in the nose of a cabin fuselage. The cowlings varied from the one extreme of an entirely exposed engine to the other in which the engine was entirely inclosed. Cooling tests were ma… more
Date: October 5, 1928
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
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Drag and Cooling With Various Forms of Cowling for A "Whirlwind" Radial Air-Cooled Engine - 2

Description: "This report gives the results of the second portion of an investigation in the twenty-foot Propeller Research Tunnel of the National Advisory Committee for Aeronautics, on the cowling and cooling of a "Whirlwind" J-5 radial air-cooled engine. The first portion pertains to tests with a cabin fuselage. This report covers tests with several forms of cowling, including conventional types, individual fairings behind the cylinders, individual hoods over the over the cylinders, and the new N. A. C. A… more
Date: December 17, 1928
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
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Tables for pressure of air on coming to rest from various speeds

Description: From Summary: "In Technical Report no. 247 of the National Advisory Committee for Aeronautics theoretical formulas are given from which was computed a table for the pressure of air on coming to rest from various speeds, such as those of aircraft and propeller blades. In that report, the table gave incompressible and adiabatic stop pressures of air for even-speed intervals in miles per hour and for some even-speed intervals in knots per hour. Table II of the present report extends the above-ment… more
Date: December 17, 1928
Creator: Zahm, A. F. & Louden, F. A.
Item Type: Refine your search to only Report
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Speed and deceleration trials of U.S.S. Los Angeles

Description: From Summary: "The trials reported in this report were instigated by the Bureau of Aeronautics of the Navy Department for the purpose of determining accurately the speed and resistance of the U. S. S. "Los Angeles" with and without water recovery apparatus, and to clear up the apparent discrepancies between the speed attained in service and in the original trials in Germany. The trials proved very conclusively that the water recovery apparatus increases the resistance about 20 per cent, which i… more
Date: June 12, 1928
Creator: De France, S. J. & Burgess, C. P.
Item Type: Refine your search to only Report
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Investigation of Air Flow in Open-Throat Wind Tunnels

Description: "Tests were conducted on the 6-inch wind tunnel of the National Advisory Committee for Aeronautics to form a part of a research on open-throat wind tunnels. The primary object of this part of the research was to study a type of air pulsation which has been encountered in open-throat tunnels, and to find the most satisfactory means of eliminating such pulsations. In order to do this it was necessary to study the effects of different variable on all of the important characteristics of the tunnel"… more
Date: September 26, 1928
Creator: Jacobs, Eastman N.
Item Type: Refine your search to only Report
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Flow and Force Equations for a Body Revolving in a Fluid

Description: Part I gives a general method for finding the steady-flow velocity relative to a body in plane curvilinear motion, whence the pressure is found by Bernoulli's energy principle. Integration of the pressure supplies basic formulas for the zonal forces and moments on the revolving body. Part II, applying this steady-flow method, finds the velocity and pressure at all points of the flow inside and outside an ellipsoid and some of its limiting forms, and graphs those quantities for the latter forms.… more
Date: December 17, 1928
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
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Flight tests on U.S.S. Los Angeles Part 1: full scale pressure distribution investigation

Description: The primary purpose of this investigation was to obtain simultaneous data on the loads and stress experience in flight by the U. S. S. Los Angeles which could be used in rigid airship structure design. A secondary object of the investigation was to determine the turning and drag characteristics of the airship. The aerodynamic loading was obtained by measuring the pressure at 95 locations on the tail surfaces, 54 on the hull, and 5 on the passenger car. These measurements were made during a seri… more
Date: August 14, 1928
Creator: De France, S. J.
Item Type: Refine your search to only Report
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Water pressure distribution on a twin-float seaplane

Description: This is the second of a series of investigations to determine water pressure distribution on various types of seaplane floats and hulls, and was conducted on a twin-float seaplane. It consisted of measuring water pressures and accelerations on a TS-1 seaplane during numerous landing and taxiing maneuvers at various speeds and angles. The results show that water pressures as great as 10 lbs. per sq. in.may occur at the step in various maneuvers and that pressures of approximately the same magnit… more
Date: December 28, 1928
Creator: Thompson, F. L.
Item Type: Refine your search to only Report
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The torsional strength of wings

Description: This report describes a simple method for calculating the position of the elastic axis of a wing structure having any number of spars. It is shown that strong drag bracing near the top and bottom of a wing greatly increases the torsional strength. An analytical procedure for finding the contribution of the drag bracing to the torsional strength and stiffness is described, based upon the principle of least work, and involving only one unknown quantity. A coefficient for comparing the torsional r… more
Date: December 1928
Creator: Burgess, C. P.
Item Type: Refine your search to only Report
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Experimental and analytical determination of the motion of hydraulically operated valve stems in oil engine injection systems

Description: This research on the pressure variations in the injection system of the N.A.C.A. Spray Photography Equipment and on the effects of these variations on the motion of the timing valve stem was undertaken in connection with the study of fuel injection systems for high-speed oil engines. The methods of analysis of the pressure variations and the general equation for the motion of the spring-loaded stem for the timing valve are applicable to a spring-loaded automatic injection valve, and in general … more
Date: December 26, 1928
Creator: Gelalles, A. G. & Rothrock, A. M.
Item Type: Refine your search to only Report
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Pressure Distribution Over a Wing and Tail Rib of a VE-7 and of a TS Airplane in Flight

Description: "This investigation was made to determine the pressure distribution over a rib of the wing and over a rib of the horizontal tail surface of an airplane in flight and to obtain information as to the time correlation of the loads occurring on these ribs. Two airplanes, VE-7 and TS, were selected in order to obtain the information for a thin and a thick wing section. In each case the pressure distribution was recorded for the full range of angle of attack in level flight and throughout violent man… more
Date: January 1928
Creator: Crowley, J. W., Jr.
Item Type: Refine your search to only Report
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Some factors affecting the reproducibility of penetration and the cut-off of oil sprays for fuel-injection engines

Description: This investigation was undertaken at the Langley Memorial Aeronautical Laboratory in connection with a general research on fuel-injection for aircraft. The purpose of the investigation was to determine the factors controlling the reproducibility of spray penetration and secondary discharges after cut-off. The development of single sprays from automatic injection valves was recorded by means of special high-speed photographic apparatus capable of taking 25 consecutive pictures of the moving spra… more
Date: 1928
Creator: Beardsley, E. G.
Item Type: Refine your search to only Report
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Characteristics of Propeller Sections Tested in the Variable Density Wind Tunnel

Description: "Tests were carried out in the variable density wind tunnel of the National Advisory Committee for Aeronautics on six airfoil sections used by the Bureau of Aeronautics as propeller sections. The sections were tested at pressures of 1 and 20 atmospheres corresponding to Reynolds numbers of about 170,000 and 3,500,000. The results obtained, besides providing data for the design of propellers, should be of special interest because of the opportunity afforded for the study of scale effect on a fam… more
Date: 1928
Creator: Jacobs, Eastman N.
Item Type: Refine your search to only Report
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Resistance and cooling power of various radiators

Description: "This reports combines the wind tunnel results of radiator tests made at the Navy Aerodynamical Laboratory in Washington during the summers of 1921, 1925, and 1926. In all, 13 radiators of various types and capacities were given complete tests for figure of merit. Twelve of these were tested for resistance to water flow and a fourteenth radiator was tested for air resistance alone, its heat dissipating capacity being known. All the tests were conducted in the 8 by 8 foot tunnel, or in its 4 by … more
Date: 1928
Creator: Smith, R. H.
Item Type: Refine your search to only Report
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Friction of aviation engines

Description: "The first portion of this report discusses measurements of friction made in the altitude laboratory of the Bureau of Standards between 1920 and 1926 under research authorization of the National Advisory Committee for Aeronautics. These are discussed with reference to the influence of speed, barometric pressure, jacket-water temperature, and throttle opening upon the friction of aviation engines. The second section of the report deals with measurements of the friction of a group of pistons diff… more
Date: 1928
Creator: Sparrow, S. W. & Thorne, M. A.
Item Type: Refine your search to only Report
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Differential Pressures on a Pitot-Venturi and a Pitot-Static Nozzle Over 360 Degrees Pitch and Yaw

Description: "Measurements of the differential pressures on two navy air-speed nozzles, consisting of a Zahm type Pitot-Venturi tube and a SQ-16 two-pronged Pitot-static tube, in a tunnel air stream of fixed speed at various angles of pitch and yaw between 0 degrees and plus or minus 180 degrees. This shows for a range over -20 degrees to +20 degrees pitch and yaw, indicated air speeds varying very slightly over 2 per cent for the Zahm type and a maximum of about 5 per cent for the SQ-16 type from the calib… more
Date: 1928
Creator: Bear, R. M.
Item Type: Refine your search to only Report
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A full-scale investigation of ground effect

Description: "This report describes flight tests which were made with the Vought VE-7 airplane to determine the effects of flying close to the ground. It is found that the drag of an airplane is materially reduced upon approaching the ground and that the reduction may be satisfactorily calculated according to theoretical formulas. Several aspects of ground effect which have had much discussion are explained" (p. 3).
Date: 1928
Creator: Reid, Elliott G.
Item Type: Refine your search to only Report
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Wind Tunnel Tests on Autorotation and The "Flat Spin"

Description: "This report deals with the autorotational characteristics of certain differing wing systems as determined from wind tunnel tests made at the Langley Memorial Aeronautical Laboratory. The investigation was confined to autorotation about a fixed axis in the plane of symmetry and parallel to the wind direction. Analysis of the tests leads to the following conclusions: autorotation below 30 degree angle of attack is governed chiefly by wing profile, and above that angle by wing arrangement" (p. 34… more
Date: 1928
Creator: Knight, Montgomery
Item Type: Refine your search to only Report
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The effect of the walls in closed type wind tunnels

Description: "A series of tests has been conducted during the period 1925-1927 by the National Advisory Committee for Aeronautics in the variable-density wind tunnel on several airfoil models of different sizes and sections to determine the effect of tunnel-wall interference and to determine a correction which can be applied to reduce the error caused thereby. The use of several empirical corrections was attempted with little success. The Prandtl theoretical corrections give the best results, and their use … more
Date: 1928
Creator: Higgins, George J.
Item Type: Refine your search to only Report
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The Performance of Several Combustion Chambers Designed for Aircraft Oil Engines

Description: "Several investigations have been made on single-cylinder test engines to determine the performance characteristics of four types of combustion chambers designed for aircraft oil engines. Two of the combustion chambers studied were bulb-type precombustion chambers, the connecting orifice of one having been designed to produce high turbulence by tangential air flow in both the precombustion chamber and the cylinder. The other two were integral combustion chambers, one being dome-shaped and the o… more
Date: 1928
Creator: Joachim, William F. & Kemper, Carlton
Item Type: Refine your search to only Report
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Aerodynamic Characteristics of Airfoils 5: Continuation of Reports Nos. 93, 124, 182, and 244

Description: "This collection of data on airfoils has been made from published reports of a number of the leading aerodynamic laboratories of this country and Europe. The information which was originally expressed according to the different customs of the several laboratories is here presented in a uniform series of charts and tables suitable for the use of designing engineers and for purposes of general reference. The authority for the results here presented is given as the name of the laboratory at which … more
Date: April 1928
Item Type: Refine your search to only Report
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Theories of flow similitude

Description: The laws of comparison of dynamically similar fluid motions are derived by three different methods based on the same principle and yielding the same or equivalent formulas. This report outlines the three current methods of comparing dynamically similar motions, more especially of fluids, initiated respectively by Newton, Stokes (or Helmholtz), and Rayleigh. These three methods, viz., the integral, the differential, and the dimensional, are enough alike to be studied profitably together. They ar… more
Date: May 7, 1928
Creator: Zahm, A. F.
Item Type: Refine your search to only Report
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