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Effect of Concentration on Ignition Delays for Various Fuel-Oxygen-Nitrogen Mixtures at Elevated Temperatures

Description: Note presenting measurements of ignition delays for mixtures of ethane, n-butane, isobutane, hydrogen, or propane with oxygen and nitrogen using a flow system with two experimental procedures. Delays were measured over a range of temperatures for each gas. Results regarding a comparison among fuels and effect of experimental procedure on absolute values of ignition delay are provided.
Date: December 1956
Creator: Anagnostou, E.; Brokaw, R. S. & Butler, J. N.
open access

Compressive Crippling of Structural Sections

Description: "A method is presented for calculating crippling stresses of structural sections as a function of material properties and the proportions of the section. The presence of formed or anisotropic material is accounted for by the use of an effective stress-strain curve. The method of analysis applies to many sections for which a procedure for calculating crippling was not previously available" (p. 1).
Date: January 1956
Creator: Anderson, Melvin S.
open access

Local Instability of the Elements of a Truss-Core Sandwich Plate

Description: The charts presented give the compressive buckling coefficients for a single-truss-core and a double-truss-core sandwich plate. These charts cover a wide range of sandwich proportions and may be used for sandwiches with unequal faces. They apply to inplane compressive loads acting parallel or perpendicular to the core direction or for various combinations of these loads. (author).
Date: July 1958
Creator: Anderson, Melvin S.
open access

Some Research Results on Sandwich Structures

Description: "The results of compressive-buckling tests of steel sandwich plates are given, and the significant parameters which affect the strength of the plates are discussed. The various types of sandwich construction are shown to be comparable on a weight-strength basis with conventional high-strength aluminum-alloy construction" (p. 1).
Date: June 1957
Creator: Anderson, Melvin S. & Updegraff, Richard G.
open access

The aerodynamic characteristics of six commonly used Airfoils over a large range of positive and negative angles of attack

Description: From Summary: "This paper presents the results of tests of six commonly used airfoils: the CYH, the N-22, the C-72, the Boeing 106, and the Gottingen 398. The lifts, drags, and pitching moments of the airfoils were measured through a large range of positive and negative angles of attack. The tests were made in the variable density wind tunnel of the National Advisory Committee for Aeronautics at a large Boeing 106, and the Gottingen 398 airfoils, the negative maximum lift coefficients were foun… more
Date: November 1931
Creator: Anderson, Raymond F.
open access

The aerodynamic characteristics of three tapered airfoils tested in the variable density wind tunnel

Description: From Summary: "This report contains the lift, drag, and moment characteristics of tapered Clark Y, Gottingen 393, and USA 45 airfoils as obtained from tests made in the Variable Density Wind Tunnel of the NACA. The results are given at both low and high Reynolds Numbers to show scale effect and to provide data for use in airplane design."
Date: February 1931
Creator: Anderson, Raymond F.
open access

Charts for determining the pitching moment of tapered wings with sweepback and twist

Description: From Summary: "This report presents a convenient method for calculating the pitching-moment characteristics of tapered wings with sweepback and twist. The method is based on the fact that the pitching-moment characteristics of a wing may be specified by giving the value of the pitching moment at zero lift and the location of the axis about which the axis is constant. Data for calculating these characteristics are presented by curves which apply to wings having a linear distribution of twist alo… more
Date: December 1933
Creator: Anderson, Raymond F.
open access

A comparison of several tapered wings designed to avoid tip stalling

Description: From Summary: "Optimum proportions of tapered wings were investigated by a method that involved a comparison of wings designed to be aerodynamically equal. The conditions of aerodynamic equality were equality in stalling speed, in induced drag at a low speed, and in the total drag at cruising speed. After the wings were adjusted to aerodynamic equivalence, the weights of the wings were calculated as a convenient method of indicating the optimum wing. The aerodynamic characteristics were calcula… more
Date: June 1939
Creator: Anderson, Raymond F.
open access

Tests of three tapered airfoils based on the N.A.C.A. 2200, the N.A.C.A.-M6, and the Clark Y sections

Description: Three tapered airfoils based on the N.A.C.A. 2200, the N.A.C.A.-M6, and the Clark Y sections were tested in the variable-density wind tunnel at a Reynolds Number of approximately 3,100,000. The models, which were of aspect ratio 6, had constant core center sections and rounded tips, and tapered in thickness from 18 percent at the roots to 9 percent at the tips. The aerodynamic characteristics are given by the usual dimensionless coefficients plotted for both positive and negative angles of atta… more
Date: January 1934
Creator: Anderson, Raymond F.
open access

An Investigation of the Effect of Blade Curvature on Centrifugal-Impeller Performance

Description: Note presenting an investigation of three centrifugal impellers, the same except for angular blade curvature, to determine the effect of the distribution of blade loading on impeller performance. Results regarding impeller efficiency, energy addition and pressure ratio, flow characteristics, and operating range are provided.
Date: May 1947
Creator: Anderson, Robert J.; Ritter, William K. & Dildine, Dean M.
open access

Charts Giving Critical Compressive Stress of Continuous Flat Sheet Divided Into Parallelogram-Shaped Panels

Description: "Charts giving the compressive-buckling stress coefficients for sheet panels of a shape occurring in swept-wing plan forms are presented. The panels are assumed to be a part of a continuous flat sheet divided by nondeflecting supports into parallelogram-shaped areas. The stability analysis was performed by the energy method and the results show that, over a wide range of panel aspect ratio, such panels are decidedly more stable than equivalent rectangular panels of the same area" (p. 1).
Date: July 1951
Creator: Anderson, Roger A.
open access

Correlation of Crippling Strength of Plate Structures With Material Properties

Description: "A correlation approach to the crippling-strength analysis of plate structures in new materials and at elevated temperatures is presented. Appropriately defined crippling-strength moduli and correlation procedures are given for predicting the effect of a change in material properties on the strength of a structure. The strength moduli are readily calculated from the effective compressive stress-strain curve for the structural material" (p. 1).
Date: January 1956
Creator: Anderson, Roger A. & Anderson, Melvin S.
open access

Determination of Coupled and Uncoupled Modes and Frequencies of Natural Vibration of Swept and Unswept Wings From Uniform Cantilever Modes

Description: Report presenting a solution for the coupled and uncoupled modes and frequencies of wings (swept or unswept) mounted on a fuselage. Characteristic equations describing symmetrical and antisymmetrical modes of vibrations are created and applied to various types of wing vibration in numerical examples.
Date: November 1948
Creator: Anderson, Roger A. & Houbolt, John C.
open access

Effect of Shear Lag on Bending Vibration of Box Beams

Description: "An analytical investigation is made of the effect of shear lag on the bending vibration of wings that are designed essentially as shallow box beams, and a procedure is outlined for incorporating this effect in the determination of bending modes and frequencies. Numerical examples show that shear-lag action in a box beam can have a large influence on its vibration characteristics. The calculations indicate that even though only a small shear-lag action may be observed in a simple static deflect… more
Date: May 1948
Creator: Anderson, Roger A. & Houbolt, John C.
open access

Charts Relating the Compressive Buckling Stress of Longitudinally Supported Plates to the Effective Deflectional and Rotational Stiffness of the Supports

Description: Report presenting a stability analysis of a long flat rectangular plate subjected to uniform longitudinal compressive stress and support along its longitudinal edges and one or more other longitudinal lines by elastic line supports. This was performed in order to provide more information about stabilization methods for thin-wing construction. The effective stiffness of different supports and the buckling observed in different structures is provided.
Date: August 1953
Creator: Anderson, Roger A. & Semonian, Joseph W.
open access

Design Data for Multipost-Stiffened Wings in Bending

Description: From Summary: "The results of a computational program are presented which give numerical values of the stiffnesses required of the various components of a multipost-stiffened wing to achieve desired buckling-stress values under bending loads. Two arrangements of the posts are considered, upright posts and posts used as diagonals of a Warren truss. This work extends and summarizes the calculations presented in NACA RM L52K10a."
Date: January 1954
Creator: Anderson, Roger A.; Johnson, Aldie E., Jr. & Wilder, Thomas W., III
open access

Effect of three design parameters on the operating characteristics of 75-millimeter-bore cylindrical roller bearings at high speeds

Description: Report presenting three experimental investigation conducted with 75-millimeter-bore cylindrical roller bearings to determine the effects of roller axial clearance ratio, cage diametral clearance ratio, and cage land width-diameter ratio on bearing operating temperatures, wear, cage slip, and high-speed operating characteristics.
Date: October 1956
Creator: Anderson, William J.
open access

Performance of 110-millimeter-bore M-1 tool steel ball bearings at high speeds, loads, and temperatures

Description: Report presenting eleven 110-millimeter-bore ball thrust bearings made of M-1 tool steel were operated over a range of DN values at mean outer-race temperatures to 678 degrees Fahrenheit. Testing occurred at a variety of thrust loads, radial loads, oil flows, and oil inlet temperatures. Results regarding the difference between tests without heat addition and tests with heat addition, fatigue failures, performance of cage materials, and oil-interruption tests are provided.
Date: January 1957
Creator: Anderson, William J.
open access

Fatigue Tests on 1/8-inch Aluminum Alloy Rivets

Description: Note presenting an investigation of the fatigue characteristics of riveted joints in aluminum alloy sheet. The purpose of this report is to summarize all the results of fatigue tests that have been made to date in the Aluminum Research Laboratories of lap joints with 1/8-inch aluminum alloy rivets.
Date: February 1945
Creator: Andrews, H. J. & Holt, M.
open access

Effects of Tip Dihedral on Lateral Stability and Control Characteristics as Determined by Tests of a Dynamic Wind Model in the Langley Free-Flight Tunnel

Description: Note presenting an investigation of the effects of tip dihedral on lateral stability and control characteristics by flight tests of models in the free-flight tunnel. The results indicate that at high lift coefficients, tip dihedral may cause a lightly damped lateral oscillation, which does not occur with full-span dihedral at similar values of effective dihedral and directional stability.
Date: July 1946
Creator: Ankenbruck, Herman O.
open access

Generalized Performance Comparison of Large Conventional, Tail Boom, and Tailless Airplanes

Description: Report presenting an investigation to determine the performance of large tailless and conventional airplanes. The primary conclusion drawn fro the testing is that large all-wing tailless airplanes may have better performance characteristics than their equivalent tail-boom airplanes for certain types of missions. Results regarding a general performance comparison, performance variations with structural weight, landing speed, and take-off distance, and performance comparison based on arbitrary de… more
Date: October 1947
Creator: Ankenbruck, Herman O. & McKinney, Marion O., Jr.
open access

An Investigation of Cotton for Parachute Cloth

Description: "This is a resume of the work of the Bureau of Standards on a cotton parachute cloth for use as a substitute for silk in the event of an emergency curtailing the supply. Cotton yarn of high strength in proportion to its weight and otherwise specially suitable for parachute cloth was developed. Cloth woven from this yarn in the bureau mill was equal or superior to parachute silk in strength and tear resistance, met the requirements with respect to air permeability, and weighed only a few tenths … more
Date: September 1931
Creator: Appel, William D. & Worner, R. K.
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