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The Aerodynamic Forces on Slender Plane- and Cruciform-Wing and Body Combinations

Description: From Introduction: "Since these results were not applicable to the present problem, a theoretical analysis of the aerodynamic properties of slender wing-body combinations was undertaken. The results of this investigation were first reported in reference 5 and were later extended in reference 6 to include cruciform-wing and body combinations. The present report summarizes and extends the theory and results previously presented in these references."
Date: 1950%
Creator: Spreiter, John R.
Partner: UNT Libraries Government Documents Department
open access

Blockage Corrections for Three-Dimensional-Flow Closed-Throat Wind Tunnels, with Consideration of the Effect of Compressibility

Description: "Theoretical blockage corrections are presented for a body of revolution and for a three-dimensional, unswept wing in a circular or rectangular wind tunnel. The theory takes account of the effects of the wake and of the compressibility of the fluid, and is based on the assumption that the dimensions of the model are small in comparison with those of the tunnel throat. Formulas are given for correcting a number of the quantities, such as dynamic pressure and Mach number, measured in wind tunnel … more
Date: 1950
Creator: Herriot, John G.
Partner: UNT Libraries Government Documents Department
open access

Blockage Corrections for Three-Dimensional-Flow Closed-Throat Wind Tunnels, With Consideration of the Effect of Compressibility

Description: "Theoretical blockage corrections are presented for a body of revolution and for a three-dimensional unswept wing in a circular or rectangular wind tunnel. The theory takes account of the effects of the wake and of the compressibility of the fluid, and is based on the assumption that the dimensions of the model are small in comparison with those of the tunnel throat. Formulas are given for correcting a number of the quantities, such as dynamic pressure and Mach number, measured in wing-tunnel t… more
Date: 1950
Creator: Herriot, John G.
Partner: UNT Libraries Government Documents Department
open access

Determination of plate compressive strengths at elevated temperatures

Description: The results of local-instability tests of h-section plate assemblies and compressive stress-strain tests of extruded 75s-t6 aluminum alloy, obtained to determine flat-plate compressive strength under stabilized elevated temperature conditions, are given for temperatures up to 600 degrees F. The results show that methods available for calculating the critical compressive stress at room temperature can also be used at elevated temperatures if the applicable compressive stress-strain curve for the… more
Date: 1950
Creator: Heimerl, George J. & Roberts, William M.
Partner: UNT Libraries Government Documents Department
open access

The effects of variations in Reynolds number between 3.0 x 10sub6 and 25.0 x 10sub6 upon the aerodynamic characteristics of a number of NACA 6-series airfoil sections

Description: Results are presented of an investigation made to determine the two-dimensional lift and drag characteristics of nine NACA 6-series airfoil section at Reynolds numbers of 15.0 x 10sub6, 20.0 x 10sub6, and 25.0 x 10sub6. Also presented are data from NACA Technical Report 824 for the same airfoils at Reynolds numbers of 3.0 x 10sub6, 6.0 x 10sub6, and 9.0 x 10sub6. The airfoils selected represent sections having variations in the airfoil thickness, thickness form, and camber. The characteristics … more
Date: 1950
Creator: Loftin, Laurence K., Jr. & Bursnall, William J.
Partner: UNT Libraries Government Documents Department
open access

Elastic and plastic buckling of simply supported solid-core sandwich plates in compression

Description: From Summary: "A solution is presented for the problem of the compressive buckling of simply supported, flat, rectangular, solid-core sandwich plates stressed either in the elastic range or in the plastic range. Charts for the analysis of long sandwich plates are presented for plates having face materials of 24S-T3 aluminum alloy, 76S-T6 Alclad aluminum alloy, and stainless steel. A comparison of computed and experimental buckling stresses of square solid-core sandwich plates indicates fair agr… more
Date: 1950
Creator: Seide, Paul & Stowell, Elbridge Z.
Partner: UNT Libraries Government Documents Department
open access

Flutter of a uniform wing with an arbitrarily placed mass according to a differential-equation analysis and a comparison with experiment

Description: A method is presented for the calculation of the flutter speed of a uniform wing carrying an arbitrarily placed concentrated mass. The method, an extension of recently published work by Goland and Luke, involves the solution of the differential equations of motion of the wing at flutter speed and therefore does not require the assumption of specific normal modes of vibration. The order of the flutter determinant to be solved by this method depends upon the order of the system of differential eq… more
Date: 1950
Creator: Runyan, Harry L. & Watkins, Charles E.
Partner: UNT Libraries Government Documents Department
open access

Free-Space Oscillating Pressures Near the Tips of Rotating Propellers

Description: "The theory is given for calculating the free-space oscillating pressures associated with a rotating propeller, at any point in space. Because of its complexity this analysis is convenient only for use in the critical region near the propeller tips where the assumptions used by Gutin to simplify his final equations are not valid. Good agreement was found between analytical and experimental results in the tip Mach number range 0.45 to two, three, four, five, six, on eight-blade propellers and fo… more
Date: 1950
Creator: Hubbard, Harvey H. & Regier, Arthur A.
Partner: UNT Libraries Government Documents Department
open access

Icing-Protection Requirements for Reciprocating-Engine Induction Systems

Description: Report presenting an investigation of the icing of aircraft-engine induction systems. Criterions for safe operation and for the design of new induction system are established through the investigation. The results were obtained from laboratory investigations of carburetor-supercharger combinations, wind-tunnel investigations of air scoops, multicylinder-engine studies, and flight investigations.
Date: 1950
Creator: Coles, Willard D.; Rollin, Vern G. & Mulholland, Donald R.
Partner: UNT Libraries Government Documents Department
open access

Method for determining the frequency-response characteristics of an element or system from the system transient output response to a known input function

Description: "A method is presented for the determination of the frequency-response characteristics of an element or system by utilizing the transient output response to a known but arbitrary input to the system. Since the application of special inputs, such as step functions or sinusoids, is often imperfect or impractical, a method for utilizing arbitrary inputs is desirable. Simple flight-test data may be reduced by this method to give the frequency response of an aircraft" (p. 1).
Date: 1950
Creator: Curfman, Howard J., Jr. & Gardiner, Robert A.
Partner: UNT Libraries Government Documents Department
open access

Small Bending and Stretching of Sandwich-Type Shells

Description: "A theory has been developed for small bending and stretching of sandwich-type shells. This theory is an extension of the known theory of homogeneous thin elastic shells. It was found that two effects are important in the present problem, which are not normally of importance in the theory of curved shells: (1) the effect of transverse shear deformation and (2) the effect of transverse normal stress deformation" (p. 1).
Date: 1950
Creator: Reissner, Eric
Partner: UNT Libraries Government Documents Department
open access

Effect of aspect ratio on the air forces and moments of harmonically oscillating thin rectangular wings in supersonic potential flow

Description: This report treats the effect of aspect ratio on the air forces and moments of an oscillating flat rectangular wing in supersonic potential flow. The linearized velocity potential for the wing undergoing sinusoidal torsional oscillations simultaneously with sinusoidal vertical translations is derived in the form of a power series in terms of a frequency parameter. The series development is such that the differential equation for the velocity potential is satisfied to the required power of the f… more
Date: January 6, 1950
Creator: Watkins, Charles E.
Partner: UNT Libraries Government Documents Department
open access

A Lift-Cancellation Technique in Linearized Supersonic-Wing Theory

Description: "A lift-cancellation technique is presented for determining load distributions on thin wings at supersonic speeds. The loading on a wing having a prescribed plan form is expressed as the loading of a known related wing (such as a two-dimensional or triangular wing) minus the loading of an appropriate cancellation wing. The lift-cancellation technique can be used to find the loading on a large variety of wings. Applications to swept wings having curvilinear plan forms and to wings having reentra… more
Date: January 16, 1950
Creator: Mirels, Harold
Partner: UNT Libraries Government Documents Department
open access

General method and thermodynamic tables for computation of equilibrium composition and temperature of chemical reactions

Description: From Summary: "A rapidly convergent successive approximation process is described that simultaneously determines both composition and temperature resulting from a chemical reaction. This method is suitable for use with any set of reactants over the complete range of mixture ratios as long as the products of reaction are ideal gases. An approximate treatment of limited amounts of liquids and solids is also included. This method is particularly suited to problems having a large number of products… more
Date: January 26, 1950
Creator: Huff, Vearl N.; Gordon, Sanford & Morrell, Virginia E.
Partner: UNT Libraries Government Documents Department
open access

Horizontal tail loads in maneuvering flight

Description: From Summary: "A method is given for determining the horizontal tail loads in maneuvering flight. The method is based upon the assignment of a load-factor variation with time and the determination of a minimum time to reach peak load factor. The tail load is separated into various components. Examination of these components indicated that one of the components was so small that it could be neglected for most conventional airplanes; therefore, the number of aerodynamic parameters needed in this … more
Date: February 9, 1950
Creator: Pearson, Henry A.; McGowan, William A. & Donegan, James J.
Partner: UNT Libraries Government Documents Department
open access

Analysis of spanwise temperature distribution in three types of air-cooled turbine blade

Description: From Summary: An approximate method for determining the allowable stress-limited blade-temperature distribution is included, with brief accounts of a method for determining the maximum allowable effective gas temperatures and the cooling-air requirements. Numerical examples that illustrate the use of the various temperature-distribution equations and of the nondimensional charts are also included.
Date: March 1, 1950
Creator: Livingood, John N. B. & Brown, W. Byron
Partner: UNT Libraries Government Documents Department
open access

Formulas for the Supersonic Loading, Lift, and Drag of Flat Swept-Back Wings With Leading Edges Behind the Mach Line

Description: "The method of superposition of linearized conical flows has been applied to the calculation of the aerodynamic properties, in supersonic flight, of thin flat, swept-back wings at an angle of attack. The wings are assumed to have rectilinear plan forms, with tips parallel to the stream, and to taper in the conventional sense. The investigation covers the moderately supersonic speed range where the Mach lines from the leading-edge apex lie ahead of the wing" (p. 1147).
Date: March 15, 1950
Creator: Cohen, Doris
Partner: UNT Libraries Government Documents Department
open access

Investigation of frequency-response characteristics of engine speed for a typical turbine-propeller engine

Description: Experimental frequency-response characteristics of engine speed for a typical turbine-propeller engine are presented. These data were obtained by subjecting the engine to sinusoidal variations of fuel flow and propeller-blade-angle inputs. Correlation is made between these experimental data and analytical frequency-response characteristics obtained from a linear differential equation derived from steady-state torque-speed relations.
Date: March 24, 1950
Creator: Taylor, Burt L., III & Oppenheimer, Frank L.
Partner: UNT Libraries Government Documents Department
open access

Effect on longitudinal stability and control characteristics of a Boeing B-29 airplane of variations in stick-force and control-rate characteristics obtained through use of a booster in the elevator-control system

Description: A longitudinal stability and control characteristics of a Boeing B-29 airplane have been measured with a booster incorporated in the elevator-control system. Tests were made to determine the effects on the handling qualities of the test airplane of variations in the pilot's control-force gradients as well as the effects of variations in the maximum rate of control motion supplied by the booster. The results of the control-rate investigation indicate that large airplanes may have satisfactory ha… more
Date: April 12, 1950
Creator: Mathews, Charles W.; Talmage, Donald B. & Whitten, James B.
Partner: UNT Libraries Government Documents Department
open access

Method of analysis for compressible flow through mixed-flow centrifugal impellers of arbitrary design

Description: A method is presented for analysis of the compressible flow between the hub and the shroud of mixed-flow impellers of arbitrary design. Axial symmetry was assumed, but the forces in the meridional (hub to shroud) plane, which are derived from tangential pressure gradients, were taken into account. The method was applied to an experimental mixed-flow impeller. The analysis of the flow in the meridional plane of the impeller showed that the rotational forces, the blade curvature, and the hub-shro… more
Date: April 13, 1950
Creator: Hamrick, Joseph T.; Ginsburg, Ambrose & Osborn, Walter M.
Partner: UNT Libraries Government Documents Department
open access

A Wind-Tunnel Investigation of the Effects of Thrust-Axis Inclination on Propeller First-Order Vibration

Description: "Data on the aerodynamic excitation of first-order vibration occurring in a representative three-blade propeller having its thrust axis inclined to the airstream at angles of 0 degree, 4.55 degrees, and 9.80 degrees are included in this report. For several representative conditions the aerodynamic excitation has been computed and compared with the measured values. Blade stresses also were measured to permit the evaluation of the blade stress resulting from a given blade aerodynamic excitation" … more
Date: April 20, 1950
Creator: Gray, W. H.; Hallissy, J. M., Jr. & Heath, A. R., Jr.
Partner: UNT Libraries Government Documents Department
open access

Comparison between theory and experiment for wings at supersonic speeds

Description: This paper presents a critical comparison made between experimental and theoretical results for the aerodynamic characteristics of wings at supersonic flight speeds. As a preliminary, a brief, nonmathematical review is given of the basic assumptions and general findings of supersonic wing theory in two and three dimensions. Published data from two-dimensional pressure-distribution tests are then used to illustrate the effects of fluid viscosity and to assess the accuracy of linear theory as com… more
Date: May 3, 1950
Creator: Vincenti, Walter G.
Partner: UNT Libraries Government Documents Department
open access

Experiments to Determine Neighborhood Reactions to Light Airplanes With and Without External Noise Reduction

Description: "The work reported was part of a program of experimentation with external noise reduction on light airplanes. This particular study was in effect a byproduct survey conceived to utilize already available equipment and personnel to further the findings of the original research and to determine reactions in populated neighborhoods to light aircraft with and without noise-reduction equipment. The findings indicate that at the 10 sites within and about metropolitan Boston the degree of noise reduct… more
Date: May 5, 1950
Creator: Elwell, Fred S.
Partner: UNT Libraries Government Documents Department
open access

The Stability of the Compression Cover of Box Beams Stiffened by Posts

Description: "An investigation is made of the buckling of the compression cover of post-stiffened box beams subjected to end moments. Charts are presented for the determination of the minimum post axial stiffnesses and the corresponding compressive buckling loads required for the compression cover to buckle with nodes through the posts. Application of the charts to design and analysis and the limitations of their use are discussed" (p. 1087).
Date: May 10, 1950
Creator: Seide, Paul & Barrett, Paul F.
Partner: UNT Libraries Government Documents Department
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