National Advisory Committee for Aeronautics (NACA) - 1,438 Matching Results

This system will be undergoing maintenance April 18th between 9:00AM and 12:00PM CDT.

Search Results

prev Results: 1177 - 1200 next
open access

Some New Problems on Shells and Thin Structures

Description: "Cylindrical shells of arbitrary section, reinforced by longitudinal and transverse members (stringers and ribs) are considered by us, for a sufficiently close spacing of the ribs, as in our previously published papers (references 1 end 2), as thin-walled orthotropic spatial systems at the cross-sections of which only axial (normal and shearing) forces can arise. The longitudinal bending and twisting moments, due to their weak effect on the stress state of the shell, are taken equal to zero. Al… more
Date: March 1949
Creator: Vlasov, V. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some New Tests at the Gottingen Laboratory

Description: The tests at the Gottingen laboratory included: friction tests on a surface treated with emaillite, verification tests on the M.V.A. 356 wing, and comparative tests of wing no. 36 at the Eiffel laboratory. The examination of all these experiments leads to the belief that, at large incidences, the speeds registered by the suction manometer of the testing chamber of the Eiffel laboratory wind tunnel are, owing to pressure drop, greater than the actual speeds. Therefore, the values of k(sub x) and… more
Date: April 1921
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Notes on Gasoline-Engine Development

Description: Experiments were carried out using a special engine with small glass windows and a stroboscope to record various aspects of engine performance. Valve position, supercharging, and torque recoil were all investigated with this experimental apparatus.
Date: July 1927
Creator: Ricardo, H. H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Principles Governing the Establishment of Meteorological Stations Along Air Routes

Description: The organization of a meteorological service for an air route involves the solution of two distinct problems: distribution and grouping of meteorological stations and communications. Experience gained in the establishment of two lines, Paris-Warsaw and Constantinople-Bucharest enables us to establish certain principles, which may be of interest to note here.
Date: March 1922
Creator: Aujames, P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Problems on the Theory of Creep

Description: "The term creep of metals is applied to the phenomenon in which, at temperatures beyond a certain limit, the metal subjected to a load slowly undergoes deformation with time. Very slow deformations for a prolonged period are cumulative and lead either to inadmissible changes in the dimensions of a structural part or to its failure. The theory of creep constitutes part of the mechanics of dense media and the mechanical formulation of the problem may be given as the following: a body is subjected… more
Date: April 1953
Creator: Rabotnov, Y. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Remarks Concerning Soaring Flight

Description: The publication of the following details is due to the desire of the editor to have the problems of soaring flight treated on the occasion of the Rhone Soaring Flight Contest. Soaring flight is defined as motorless flight without loss of height. Some calculations are provided in order to maximize the potential effects of wind and air currents.
Date: October 1921
Creator: Prandtl, L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Some Studies on the Flow of a Gas in the Region of Transition Through the Velocity of Sound

Description: "The two-dimensional motion of an incompressible fluid about a closed contour with a definite velocity in magnitude and direction at infinity is considered. If, without changing the direction of the velocity at infinity, the magnitude is increased, the configuration of the streamlines remains unchanged and only the numbering of the stream function changes. There exists only one family of curves that can serve as streamlines in the incompressible flow about a given contour (at a given angle of a… more
Date: April 1950
Creator: Kiebel, I. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

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.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Span as a Fundamental Factor in Airplane Design

Description: Previous theoretical investigations of steady curvilinear flight did not afford a suitable criterion of "maneuverability," which is very important for judging combat, sport and stunt-flying airplanes. The idea of rolling ability, i.e., of the speed of rotation of the airplane about its X axis in rectilinear flight at constant speed and for a constant, suddenly produced deflection of the ailerons, is introduced and tested under simplified assumptions for the air-force distribution over the span.… more
Date: September 1928
Creator: Lachmann, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Specializing for Record-Breaking

Description: This report seeks to determine what constitutes airplane performance and what line should be followed in seeking to break records if the designer is given a free hand. Some of the considerations for designers include the ratio of engine power to wing area, minor refinements, low wing loading, and duration.
Date: February 1924
Creator: Warner, Edward P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Speed and Pressure Recording in Three-Dimensional Flow

Description: "Van der Megge Zijnen's spherical Pitot tube with its 5 test holes insures a simultaneous record of static pressure and magnitude and direction of velocity in three-dimensional flow. The report treats the method as well as the range of application of this Pitot in the light of modern knowledge on flow around spheres" (p. 1).
Date: October 1932
Creator: Krisam, F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Speed Limits of Aircraft

Description: This paper is restricted to the question of attainable speed limits and attacks the problem from different angles. Theoretical limits due to air resistance are presented along with design factors which may affect speed such as wing loads, wing areas, wing section shifting, landing speeds, drag-lift ratios, and power coefficients.
Date: May 1923
Creator: Everling, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spindled and Hollow Spars

Description: "The most usual method of arriving at the maximum amount of spindling or hollowing out permissible in the case of any particular spar section is by trial and error, a process which is apt to become laborious in the absence of good guessing - or luck. The following tables have been got out with the object of making it possible to arrive with certainty at a suitable section at the first attempt" (p. 1).
Date: October 1926
Creator: Blyth, J. D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Spontaneous Combustion of Hydrogen

Description: It is shown by the author's experiments that hydrogen which escapes to the atmosphere through openings in the system may burn spontaneously if it contains dust. Purely thermal reasoning can not account for the combustion. It seems to be rather an electrical ignition. In order to determine whether the cause of the spontaneous ignition was thermo-chemical, thermo-mechanical, or thermo-electrical, the experiments in this paper were performed.
Date: March 4, 1922
Creator: Pothmann, P. & Nusselt, Wilhelm
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of Airplanes

Description: The author attempts to correct the misconception that piloting an airplane requires extraordinary skill and balance. He also tries to show that airplanes are extremely stable in flight. Some of the major points covered in this article include: automatic pilots, airplanes designed to be stable, and the reliance on mathematics to help in designing stable aircraft.
Date: May 1922
Creator: Warner, Edward P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of Cylindrical and Conical Shells of Circular Cross Section, with Simultaneous Action of Axial Compression and External Normal Pressure

Description: "We consider in this report the determination of the upper limit of critical loads in the case of simultaneous action of a compressive force, uniformly distributed over plane cross sections, and of isotropic external normal pressure on cylindrical or conical shells of circular cross section. As a starting point we use the differential equations for neutral equilibrium of conical shells which have been used for the solution of the problem of stability of conical shells under torsion and under ax… more
Date: April 1958
Creator: Mushtari, K. M. & Sachenkov, A. V.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Stability of Laminar Flow Past a Sphere

Description: "As a contribution to the problem of turbulence on a surface of rotation, the method of small oscillation is applied to the flow past a sphere. It was found that the method developed for two-dimensional flow is applicable without modifications. The frictional layer in the vicinity of the stagnation point of a surface of rotation is less stable against small two-dimensional disturbances than in the stagnation point itself, as proved from an analysis of the velocity distribution made by Homann" (… more
Date: June 1942
Creator: Pretsch, J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Stability of Orthotropic Elliptic Cylinders in Pure Bending

Description: "The theoretical critical bending stress of elliptic cylindrical shells is determined on the assumption of infinite shell length and absence of local instability phenomena. The results of the tests on isotropic elliptic cylindrical shells stressed in bending are compared with the theoretical results. The practical applicability of the theory is discussed" (p. 1).
Date: July 1937
Creator: Heck, O. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of Plates and Shells Beyond the Proportional Limit

Description: In the present paper is examined the method of investigating the stability of plates and shells beyond the elastic limit, that proceeds from the generalization of the Hencky-Mises theory of elastico-plastic deformations given in the works of Smirnov-Alyayev, Schmidt, and in our papers.
Date: October 1947
Creator: Ilyushin, A. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of Rectangular Plates With Longitudinal or Transverse Stiffeners Under Uniform Compression

Description: In the present paper, the complete buckling conditions of stiffened plates are being developed for uniform compression. We shall treat plates with one or two longitudinal or transverse stiffeners at any point, discuss the buckling conditions, and evaluate them for different cases.
Date: August 1939
Creator: Barbré, R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stability of the Cylindrical Shell of Variable Curvature

Description: "This report is a first attempt to devise a calculation method for representing the buckling behavior of cylindrical shells of variable curvature. The problem occurs, for instance, in dimensioning wing noses, the stability of which is decisively influenced by the variability of curvature. The calculation is made possible by simplifying the stability equations (permissible for the shell of small curvature) and by assuming that the curvature 1/R as a function of the arc lengths can be represented… more
Date: July 1951
Creator: Marguerre, Karl
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stagnation Temperature Recording

Description: "The present report deals with the development of a thermometer for recording stagnation temperature in compressible mediums in turbulent flow within 1 to 2 percent error of the adiabatic temperature in the stagnation point, depending upon the speed. This was achieved by placing the junction of a thermocouple near the stagnation point of an aerodynamically beneficial body, special care being taken to assure an uninterrupted supply of fresh compressed air on the junction together with the use of… more
Date: January 1941
Creator: Wimmer, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Stall-Proof Airplanes

Description: Report investigating some characteristics of aircraft stall, including the following: Is the danger of stalling necessarily inherent in the airplane in its present form and structure, or can it be diminished or eliminated by suitable means? Do we possess such means or devices and how must they operate?
Date: January 1927
Creator: Lachmann, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen