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Charts expressing the time, velocity, and altitude relations for an airplane diving in a standard atmosphere

Description: In this report charts are given showing the relation between time, velocities, and altitude for airplanes having various terminal velocities diving in a standard atmosphere. The range of starting altitudes is from 8,000 to 32,000 feet, and the terminal velocities vary from 150 to 550 miles per hour. A comparison is made between an experimental case and the results obtained from the charts. Examples pointing out the use of the charts are included.
Date: April 1937
Creator: Pearson, H. A.
Partner: UNT Libraries Government Documents Department
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Stability of Structural Members Under Axial Load

Description: "The principles of the Cross method of moment distribution are used to check the stability of structural members under axial load. A brief theoretical treatment of the subject, together with an illustrative problem, is included as well as a discussion of the reduced modulus at high stresses and a set of tables to aid in the solution of practical problems" (p. 1).
Date: October 1937
Creator: Lundquist, Eugene E.
Partner: UNT Libraries Government Documents Department
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Theoretical span loading and moments of tapered wings produced by aileron deflection

Description: "The effect of tapered ailerons on linearly tapered wings is theoretically determined. Four different aileron spans are considered for each of three wing aspect ratios and each of four wing taper ratios. The change in lift on one half of the wing, the rolling moment, the additional induced drag, and the yawing moment, due to aileron deflection, are represented by non dimensional coefficients" (p. 1).
Date: January 1937
Creator: Pearson, H. A.
Partner: UNT Libraries Government Documents Department
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Hydrodynamic tests in the N.A.C.A. tank of a model of the hull of the Short Calcutta flying boat

Description: "The hydrodynamic characteristics of a model of the hull of the Short Calcutta (N.A.C.A. Model 47) are presented in non-dimensional form. This model represents one of a series of hulls of successful foreign and domestic flying boats the characteristics of which are being obtained under similar test conditions in the N.A.C.A. tank. The take-off distance and time for a flying boat having the hull of the Calcutta are compared at two values of the gross load with the corresponding distances and tim… more
Date: January 1937
Creator: Ward, Kenneth E.
Partner: UNT Libraries Government Documents Department
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Increasing the Strength of Aluminum-Alloy Columns by Prestressing

Description: A series of tests was made in which the column strength of 17ST tubing was increased as much as 50 percent by prestressing the tubing to 40,000 pounds per square inch in compression under conditions of support that prevented column failure at this stress. This prestressing achieves it's beneficial effects entirely by improving the compressive properties of the material, principally the proportional limit.
Date: October 1937
Creator: Holt, M. & Hartman, E. C.
Partner: UNT Libraries Government Documents Department
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The Behavior of Thin-Will Monocoque Cylinders Under Torsional Vibration

Description: "Curves of forced frequency against amplitude are presented for the conditions where the forced frequency is both increased and decreased into the resonant range. On the basis of these curves it is shown that the practical resonance frequency is the point where wrinkling first occurs and that the resonance frequency will be subject to considerable travel once permanent wrinkles appear in the vibrating shell. The decreasing mode of striking resonance is found to be by far the most destructive co… more
Date: August 1937
Creator: Pekelsma, Robert E.
Partner: UNT Libraries Government Documents Department
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Free-spinning wind-tunnel tests of a low-wing monoplane with systemic changes in wings and tails 1: Basic loading condition

Description: A series of tests was made at the National Advisory Committee for Aeronautics (NACA) free-spinning tunnel to determine the effect of systematic changes in wing and tail arrangement upon steady-spinning and recovery characteristics of a conventional low-wing monoplane model for a basic loading condition. 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 2… more
Date: August 1937
Creator: Seidman, Oscar & Neihouse, A. I.
Partner: UNT Libraries Government Documents Department
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Considerations affecting the additional weight required in mass balance of ailerons

Description: "This paper is essentially a consideration of mass balance of ailerons from a preliminary design standpoint, in which the extra weight of the mass counterbalance is the most important phase of the problem. Equations are developed for the required balance weight for a simple aileron and this weight is correlated with the mass-balance coefficient. It is concluded the location of the c.g. of the basic aileron is of paramount importance and that complete mass balance imposes no great weight penalty… more
Date: August 1937
Creator: Diehl, W. S.
Partner: UNT Libraries Government Documents Department
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Full scale span load distribution on a tapered wing with split flaps of various spans

Description: Pressure-distribution tests were conducted in the full-scale wind tunnel on a 2:1 tapered U.S.A. 45 airfoil equipped with 20 percent chord split trailing-edge flaps of various spans. A special installation was employed in the tests utilizing a half-span airfoil mounted vertically above a reflection plane. The airfoil has a constant chord center section and rounded tips and is tapered in thickness from 18 percent c at the root to 9 percent c at the tip. The aerodynamic characteristics, given by … more
Date: February 1937
Creator: Parsons, John F. & Silverstein, Abe
Partner: UNT Libraries Government Documents Department
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Effect of Air-Entry Angle on Performance of a 2-Stroke-Cycle Compression-Ignition Engine

Description: "An investigation was made to determine the effect of variations in the horizontal and vertical air-entry angles on the performance characteristics of a single-cylinder 2-stroke-cycle compression-ignition test engine. Performance data were obtained over a wide range of engine speed, scavenging pressure, fuel quantity, and injection advance angle with the optimum guide vanes. Friction and blower-power curves are included for calculating the indicated and net performances" (p. 1).
Date: August 1937
Creator: Earle, Sherod L. & Dutee, Francis J.
Partner: UNT Libraries Government Documents Department
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Pressure Distribution Over a Clark Y-H Airfoil Section With a Split Flap

Description: "An investigation was made in the N.A.C.A. 7 by 10 foot wind tunnel of the distribution of air pressure over one chord section of a Clark Y-H airfoil with a split flap. The results obtained are given in the form of diagrams showing the chordwise distribution of pressure on both airfoil and flap as plots of calculated aerodynamic coefficients for both airfoil and flap" (p. 1).
Date: December 1937
Creator: Wenzinger, Carl J.
Partner: UNT Libraries Government Documents Department
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Plastics as structural materials for aircraft

Description: The purpose here is to consider the mechanical characteristics of reinforced phenol-formaldehyde resin as related to its use as structural material for aircraft. Data and graphs that have appeared in the literature are reproduced to illustrate the comparative behavior of plastics and materials commonly used in aircraft construction. Materials are characterized as to density, static strength, modulus of elasticity, resistance to long-time loading, strength under repeated impact, energy absorptio… more
Date: December 1937
Creator: Kline, G. M.
Partner: UNT Libraries Government Documents Department
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A Sound Pressure-Level Meter Without Amplification

Description: "The N.A.C.A. has developed a simple pressure-level meter for the measurement of sound-pressure levels above 70 db. The instrument employs a carbon microphone but has no amplification. The source of power is five flashlight batteries. Measurements may be made up to the threshold of feeling with an accuracy of plus or minus 2 db; band analysis of complex spectra may be made if desired" (p. 1).
Date: December 1937
Creator: Stowell, E. Z.
Partner: UNT Libraries Government Documents Department
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Free spinning wind-tunnel tests of a low-wing monoplane with systematic wings and tails 2: Mass distributed along the fuselage

Description: Report presenting a study of eight wings and three tails covering a wide range of aerodynamic characteristics in 24 wing-tail combinations. Observations were made of the steady spin for four control settings and of recoveries for five control manipulations. The effect of wing shape, tail arrangement, control settings, relationships between spin characteristics, and comparison with results for basic loading are provided.
Date: December 1937
Creator: Seidman, Oscar & Neihouse, A. I.
Partner: UNT Libraries Government Documents Department
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Static Thrust Analysis of the Lifting Airscrew

Description: "This report presents the results of a combined theoretical and experimental investigation conducted at the Georgia School of Technology on the static thrust of the lifting air screw of the type used in modern autogiros and helicopters. The theoretical part of this study is based on Glauert's analysis but certain modifications are made that further clarify and simplify the problem. Of these changes the elimination of the solidity as an independent parameter is the most important" (p. 1).
Date: December 1937
Creator: Knight, Montgomery & Hefner, Ralph A.
Partner: UNT Libraries Government Documents Department
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Wing-Fuselage Interference - Comparison of Conventional and Airfoil-Type-Fuselage Combinations

Description: Report presenting tests of wing-fuselage combinations employing an airfoil-type fuselage in the variable-density wind tunnel as part of a wing-fuselage program. The models were designed to simulate an existing moderate-size transport airplane of that type. Results regarding some general comparisons, lift distribution and induced drag, and drag in high-speed flight are provided.
Date: March 1937
Creator: Jacobs, Eastman N. & Sherman, Albert
Partner: UNT Libraries Government Documents Department
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Tapered Wings, Tip Stalling, and Preliminary Results From Tests of the Stall-Control Flap

Description: Report presenting a consideration of the general problem of stalling as affecting the safety of airplanes. The increased difficulties associated with modern efficient wings, particularly highly tapered wings and high-life devices, are discussed and means are considered for avoiding these difficulties.
Date: November 1937
Creator: Jacobs, Eastman N.
Partner: UNT Libraries Government Documents Department
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The Scale Effect in Towing Tests With Airplane-Float Systems

Description: "The present report includes a description of the making of three-component measurements on a full-size float mounted on an actual airplane and the comparison of the results with those from two models of the same form but of different size which had been tested in the towing tank. The purpose of the comparison is to determine the effect of the Reynolds Number on the results of model tank tests. Following a brief discussion of previous tests intended to elucidate the problem of scale effect on f… more
Date: May 1937
Creator: Schmidt, Rudolph
Partner: UNT Libraries Government Documents Department
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The Source of Propeller Noise

Description: A two blade propeller of 40 cm diameter and zero pitch was explored for its noise development; it could be whirled up to 17,000 rpm - i.e., a tip speed of 355 meters/second. To obtain the power loss N(sub m) of the propeller for comparison with the produced acoustical power N(sub A) the engine performance characteristics were measured with and without propeller. The result is the sought-for relation c, that is, curve c' after correction with the engine efficiency.
Date: May 1937
Creator: Ernsthausen, W.
Partner: UNT Libraries Government Documents Department
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Experimental investigation of the problem of surface roughness

Description: Based on the universal laws of turbulent velocity distribution at rough and smooth walls, there is in the present work presented a method that allows surface roughness tests and in particular, measurements on the roughness of ship surfaces to be carried out in a much simpler manner. The types of roughness investigated were in the form of flat, rough plates installed in a square-section rectangular channel, the other three walls always being smooth. Twenty-one plates of various roughness were in… more
Date: April 1937
Creator: Schlichting, H.
Partner: UNT Libraries Government Documents Department
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Turbulent Boundary Layer of an Airfoil

Description: A need has arisen for a new determination of the velocity profiles in the boundary layer. Assuming that the character of the velocity distribution depends to a large extent on the character of the shear distribution across the boundary layer, we shall consider the nature of the shear distribution for a boundary layer with a pressure gradient.
Date: April 1937
Creator: Fediaevsky, K.
Partner: UNT Libraries Government Documents Department
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On the Actual Loads on Airplane Landing Gears

Description: This investigation was intended to throw light on a number of problems: 1) obtain a time history of the force acting on the gear wheels during take-off and landing runs; 2) obtain the time history of the direction of this force (magnitude of its three components along the coordinate axes); 3) derive conclusions as to the design load factors. In connection with the latter, of special interest was the solution of such problems as: a) the dynamic loads in the three main landing attitudes; b) the p… more
Date: March 1937
Creator: Shiskin, S.
Partner: UNT Libraries Government Documents Department
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Some Experiments on the Slipstream Effect

Description: The models designated "Torino 30, 31, 32" are horizontal tail surfaces of rectangular, triangular, and elliptical plan form and all of the same profile section. Tests were carried out with the object being to determine the effect of the propeller slipstream on the aerodynamical characteristics of the horizontal stabilizer. The results presented correspond to a first series of tests made without an interposed wing and in which the distance between the plane of the propeller disk and the tail was… more
Date: March 1937
Creator: Ferrari, C.
Partner: UNT Libraries Government Documents Department
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