National Advisory Committee for Aeronautics (NACA) - 334 Matching Results

Search Results

Results: 1 - 24 next
open access

Determination of Stresses in Gas-turbine Disks Subjected to Plastic Flow and Creep

Description: From Summary: "A finite-difference method previously presented for computing elastic stresses in rotating disks is extended to include the computation of the disk stresses when plastic flow and creep are considered. A finite-difference method is employed to eliminate numerical integration and to permit nontechnical personnel to make the calculations with a minimum of engineering supervision. Illustrative examples are included to facilitated explanation of the procedure by carrying out the compu… more
Date: 1948
Creator: Millenson, M. B. & Manson, S. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

On the plane potential flow past a lattice of arbitrary airfoils

Description: The two-dimensional, incompressible potential flow past a lattice of airfoils of arbitrary shape is investigated theoretically. The problem is treated by usual methods of conformal mapping in several stages, one stage corresponding to the mapping of the framework of the arbitrary line lattice and another significant stage corresponding to the Theodorsen method for the mapping of the arbitrary single wing profile into a circle. A particular feature in the theoretical treatment is the special han… more
Date: November 19, 1943
Creator: Garrick, I. E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Icing-protection requirements for reciprocating-engine induction system

Description: From Summary: "Despite the development of relatively ice-free fuel-metering systems, the widespread use of alternate and heated-air intakes, and the use of alcohol for emergency de-icing, icing of aircraft-engine induction systems is a serious problem. Investigations have been made to study and to combat all phases of this icing problem. From these investigations, criterions for safe operation and for design of new induction systems have been established. The results were obtained from laborato… more
Date: June 20, 1949
Creator: Coles, Willard D.; Rollin, Vern G. & Mulholland, Donald R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Line-Vortex Theory for Calculation of Supersonic Downwash

Description: "The perturbation field induced by a line vortex in a supersonic stream and the downwash behind a supersonic lifting surface are examined to establish approximate methods for determining the downwash behind supersonic wings. Lifting-lines methods are presented for calculating supersonic downwash. A bent lifting-line method is proposed for computing the downwash field behind swept wings. When applied to triangular wings with subsonic leading edges, this method gives results that, in general, are… more
Date: April 29, 1949
Creator: Mirels, Harold & Haefeli, Rudolph C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A radar method of calibrating airspeed installations on airplanes in maneuvers at high altitudes and at transonic and supersonic speeds

Description: A method of calibrating the static-pressure source of a pitot static airspeed installation on an airplane in level flight, dives, and other maneuvers at high altitude and at transonic and supersonic speeds is described. The method principally involves the use of radar-phototheodolite tracking equipment. The various sources of error in the method are discussed and sample calibrations are included.
Date: August 31, 1949
Creator: Zalovcik, John A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The reversibility theorem for thin airfoils in subsonic and supersonic flow

Description: A method introduced by Munk is extended to prove that the light-curve slope of thin wings in either subsonic flow or supersonic flow is the same when the direction of flight of the wing is reversed. It is also shown that the wing reversal does not change the thickness drag, damping-in-roll parameter or the damping-in-pitch parameter.
Date: June 26, 1949
Creator: Brown, Clinton E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Equilibrium Operating Performance of Axial-Flow Turbojet Engines by Means of Idealized Analysis

Description: "A method of predicting equilibrium operating performance of turbojet engines has been developed, with the assumption of simple model processes for the components. Results of the analysis are plotted in terms of dimensionless parameters comprising critical engine dimensions and over-all operating variables. This investigation was made of an engine in which the ratio of axial inlet-air velocity to compressor-tip velocity is constant, which approximates turbojet engines with axial-flow compressor… more
Date: February 25, 1949
Creator: Sanders, John C. & Chapin, Edward C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Comparative drag measurements at transonic speeds of rectangular sweptback NACA 65-009 airfoils mounted on a freely falling body

Description: From Summary: "Directly comparable drag measurements have been made of an airfoil with a conventional rectangular plan form and an airfoil with a sweptback plan form mounted on freely falling bodies. Both airfoils had NACA 65-009 sections and were identical in span, frontal area, and chord perpendicular to the leading edge. The sweptback plan form incorporated a sweepback angle of 45 degrees. The data obtained have been used to establish the relation between the airfoil drag coefficients and th… more
Date: August 9, 1945
Creator: Mathews, Charles W. & Thompson, Jim Rogers
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Theoretical comparison of several methods of thrust augmentation for turbojet engines

Description: "A theoretical investigation of tail-pipe burning, water injection at the compressor inlet, combination tail-pipe burning plus water injection, bleedoff, and rocket-assist methods thrust augmentation for turbojet engines was made for an engine representative of those in current use. The effect of augmented liquid ratio on augmented thrust ratio and the effects of altitude and flight Mach number on the performance of various methods were determined. The additional take-off weight involved by the… more
Date: October 27, 1948
Creator: Hall, Eldon W. & Wilcox, E. Clinton
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Propeller charts for the determination of the rotational speed for the maximum ratio of the propulsive efficiency to the specific fuel consumption

Description: A set of propeller operating efficiency charts, based on a coefficient from which the propeller rotational speed has been eliminated, is presented. These charts were prepared with data obtained from tests of full-size metal propellers in the NACA propeller-research tunnel. Working charts for nine propeller-body combinations are presented, including results from tests of dual-rotating propellers. These charts are to be used in the calculation of the range and the endurance of airplanes equipped … more
Date: December 11, 1940
Creator: Biermann, David & Conway, Robert N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

High-Speed Tests of a Model Twin-Engine Low-Wing Transport Airplane

Description: Report presents the results of force tests made of a 1/8-scale model of a twin-engine low-wing transport airplane in the NACA 8-foot high-speed tunnel to investigate compressibility and interference effects of speeds up to 450 miles per hour. In addition to tests of the standard arrangement of the model, tests were made with several modifications designed to reduce the drag and to increase the critical speed.
Date: 1942
Creator: Becker, John V. & Leonard, Lloyd H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The mean aerodynamic chord and the aerodynamic center of a tapered wing

Description: A preliminary study of pitching-moment data on tapered wings indicated that excellent agreement with test data was obtained by locating the quarter-chord point of the average chord on the average quarter-chord point of the semispan. The study was therefore extended to include most of the available data on tapered-wing models tested by the NACA.
Date: June 16, 1942
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

On a New Method for Calculating the Potential Flow Past a Body of Revolution

Description: "A new method is presented for obtaining the velocity potential of the flow about a body of revolution moving uniformly in the direction of its axis of symmetry in a fluid otherwise at rest. This method is based essentially on the fact that the form of the differential equation for the velocity potential is invariant with regard to conformal transformation of the meridian plane. By means of the conformal transformation of the meridian profile into a circle a system of orthogonal curvilinear coo… more
Date: May 18, 1942
Creator: Kaplan, Carl
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Operating Temperatures of a Sodium-Cooled Exhaust Valve as Measured by a Thermocouple

Description: Report presents the results of a thermocouple installed in the crown of a sodium-cooled exhaust valve. The valve was tested in an air-cooled engine cylinder and valve temperatures under various engine operating conditions were determined. A temperature of 1337 degrees F. was observed at a fuel-air ratio of 0.064, a brake mean effective pressure of 179 pounds per square inch, and an engine speed of 2000 r.p.m.
Date: 1943
Creator: Sanders, J. C.; Wilsted, H. D. & Mulcahy, B. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Requirements for Satisfactory Flying Qualities of Airplanes

Description: Report discusses the results of an analysis of available data to determine what measured characteristics are significant in defining satisfactory flying qualities, what characteristics are reasonable to require of an airplane, and what influence the various design features have on the observed flying qualities.
Date: March 24, 1941
Creator: Gilruth, R. R.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The induction of water to the inlet air as a means of internal cooling in aircraft-engine cylinders

Description: Report presents the results of investigations conducted on a full-scale air-cooled aircraft-engine cylinder of 202-cubic inch displacement to determine the effects of internal cooling by water induction on the maximum permissible power and output of an internal-combustion engine. For a range of fuel-air and water-fuel ratios, the engine inlet pressure was increased until knock was detected aurally, the power was then decreased 7 percent holding the ratios constant. The data indicated that water… more
Date: 1943
Creator: Rothrock, Addison M.; Krsek, Alois, Jr. & Jones, Anthony W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Performance of NACA eight-stage axial-flow compressor designed on the basis of airfoil theory

Description: "The NACA has conducted an investigation to determine the performance that can be obtained from a multistage axial-flow compressor based on airfoil research. A theory was developed; an eight-stage axial-flow compressor was designed, constructed, and tested. The performance of the compressor was determined for speeds from 5000 to 14,000 r.p.m with varying air flow at each speed" (p. 81).
Date: August 1, 1944
Creator: Sinnette, John T., Jr.; Schey, Oscar W. & King, J. Austin
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Derivation of charts for determining the horizontal tail load variation with any elevator motion

Description: From Summary: "The equations relating the wing and tail loads are derived for a unit elevator displacement. These equations are then converted into a nondimensional form and charts are given by which the wing- and tail-load-increment variation may be determined under dynamic conditions for any type of elevator motion and for various degrees of airplane stability. In order to illustrate the use of the charts, several examples are included in which the wing and tail loads are evaluated for a numb… more
Date: November 23, 1942
Creator: Pearson, Henry A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Identification of knock in NACA high-speed photographs of combustion in a spark-ignition engine

Description: Report presents the results of a study of combustion in a spark-ignition engine given in NACA Technical Reports 704 and 727. The present investigation was made with the NACA high-speed motion-picture camera, operating at 40,000 photographs a second, and with a cathode-ray oscillograph operating on a piezoelectric pick-up in the combustion chamber. Photographs are presented showing that the origin of knock is not necessarily in the end gas. The data obtained indicates that knock takes place only… more
Date: November 14, 1942
Creator: Miller, Cearcy D. & Olsen, H. Lowell
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

A Theoretical Investigation of the Lateral Oscillations of an Airplane With Free Rudder With Special Reference to the Effect of Friction

Description: "Charts showing the variation in dynamic stability with the rudder hinge-moment characteristics are presented. A stabilizing rudder floating tendency combined with a high degree of aerodynamic balance is shown to lead to oscillations of increasing amplitude. This dynamic instability is increased by viscous-friction in the rudder control system" (p. 147).
Date: March 4, 1943
Creator: Greenberg, Harry & Sternfield, Leonard
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Tests of Airfoils Designed to Delay the Compressibility Burble

Description: "Fundamental investigations of compressibility phenomena for airfoils have shown that serious adverse changes of aerodynamic characteristics occur as the local speed over the surface exceeds the local speed of sound. These adverse changes have been delayed to higher free-stream speeds by development of suitable airfoil shapes. The method of deriving such airfoil shapes is described, and aerodynamic data for a wide range of Mach numbers obtained from tests of these airfoils in the Langley 24-inc… more
Date: 1943
Creator: Stack, John
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Theory of Propellers 2: Method for Calculating the Axial Interference Velocity

Description: "A technical method is given for calculating the axial interference velocity of a propeller. The method involves the use of certain weight functions P, Q, and F. Numerical values for the weight functions are given for two-blade, three-blade, and six-blade propellers" (p. 1).
Date: 1944
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Theory of Propellers 3: The Slipstream Contraction With Numerical Values for Two-Blade and Four-Blade Propellers

Description: "As the conditions of the ultimate wake are concerned both theoretically and practically, the magnitude of the slipstream contraction has been calculated. It will be noted that the contraction in a representative case is of the order of only 1 percent of the propeller diameter. In consequence, all calculations need involve only first-order effects. Curves and tables are given for the contraction coefficient of two-blade and four-blade propellers for various values of the advance ratio; the cont… more
Date: 1944
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

The Theory of Propellers 4: Thrust, Energy, and Efficiency Formulas for Single and Dual Rotating Propellers With Ideal Circulation Distribution

Description: "Simple and exact expressions are given for the efficiency of single and dual rotating propellers with ideal circulation distribution as given by the Goldstein functions for single-rotating propellers and by the new functions for dual-rotating propellers from part I of the present series. The efficiency is shown to depend primarily on a defined load factor and, to a very small extent, on an axial loss factor. Tables and charts are included for practical use of the results. The present paper is … more
Date: October 12, 1944
Creator: Theodorsen, Theodore
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
Back to Top of Screen