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Theoretical calculation of the power spectra of the rolling and yawing moments on a wing in random turbulence

Description: The correlation functions and power spectra of the rolling and yawing moments on an airplane wing due to the three components of continuous random turbulence are calculated. The rolling moments to the longitudinal (horizontal) and normal (vertical) components depend on the spanwise distributions of instantaneous gust intensity, which are taken into account by using the inherent properties of symmetry of isotropic turbulence. The results consist of expressions for correlation functions or spectr… more
Date: September 6, 1956
Creator: Eggleston, John M. & Diederich, Franklin W.
Item Type: Refine your search to only Report
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Application of several methods for determining transfer functions and frequency response of aircraft from flight data

Description: In the process of analyzing the longitudinal frequency-response characteristics of aircraft, information on some of the methods of analysis has been obtained by the Langley Aeronautical Laboratory of the National Advisory Committee for Aeronautics. In the investigation of these methods, the practical applications and limitations were stressed. In general, the methods considered may be classed as: (1) analysis of sinusoidal response, (2) analysis of transient response as to harmonic content thro… more
Date: 1954
Creator: Eggleston, John M. & Mathews, Charles W.
Item Type: Refine your search to only Report
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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.
Item Type: Refine your search to only Report
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Systematic two-dimensional cascade tests of NACA 65-series compressor blades at low speeds

Description: The performance of NACA 65-series compressor blade section in cascade has been investigated systematically in a low-speed cascade tunnel. Porous test-section side walls and for high-pressure-rise conditions, porous flexible end walls were employed to establish conditions closely simulating two-dimensional flow. Blade sections of design lift coefficients from 0 to 2.7 were tested over the usable angle-of-attack range for various combinations of inlet-flow angle. A sufficient number of combinatio… more
Date: January 31, 1958
Creator: Emery, James C.; Herrig, L. Joseph; Erwin, John R. & Felix, A. Richard
Item Type: Refine your search to only Report
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One-Dimensional Analysis of Choked-Flow Turbines

Description: "Turbines for most applications requiring high work output per stage have one or more blade rows which are choked. This analysis indicated that the area ratios and equivalent blade speed are the controlling factors in the design and operation of such turbines. Six criteria are stated that will aid in establishing from test data of multistage turbines which blade rows are choked and which are not" (p. 1).
Date: 1953
Creator: English, Robert E. & Cavicchi, Richard H.
Item Type: Refine your search to only Report
open access

Effect of chord size on weight and cooling characteristics of air-cooled turbine blades

Description: An analysis has been made to determine the effect of chord size on the weight and cooling characteristics of shell-supported, air-cooled gas-turbine blades. In uncooled turbines with solid blades, the general practice has been to design turbines with high aspect ratio (small blade chord) to achieve substantial turbine weight reduction. With air-cooled blades, this study shows that turbine blade weight is affected to a much smaller degree by the size of the blade chord.
Date: November 13, 1956
Creator: Esgar, Jack B.; Schum, Eugene F. & Curren, Arthur N.
Item Type: Refine your search to only Report
open access

The zero-lift drag of a slender body of revolution (NACA RM-10 research model) as determined from tests in several wind tunnels and in flight at supersonic speeds

Description: From Summary: "The results of tests of a slender body of revolution designated the NACA rm-10 have been compiled from various NACA test facilities. Zero-lift drag data are presented for a Reynolds number range from about 1 x 10(6) to 40 x 10(6) from several wind tunnels and from about 12 x 10(6) to 140 x 10(6) from free-flight tests. The Mach numbers covered include 1.5 to 2.4 for the wind-tunnel data and 0.85 to 2.5 for the flight results. The wind tunnel models were tested with and without 60… more
Date: April 16, 1953
Creator: Evans, Albert J.
Item Type: Refine your search to only Report
open access

A wind-tunnel investigation of the aerodynamic characteristics of a full-scale supersonic-type three-blade propeller at Mach numbers to 0.96

Description: From Summary: "An investigation of the characteristics of a full-scale supersonic-type propeller has been made in the Langley 16-foot transonic tunnel with the 6000-horsepower propeller dynamometer. The tests covered a range of blade angles from 20.2 degrees to 60.2 degrees at forward Mach numbers up to 0.96. The results showed that envelope efficiency at an advance ratio of 2.8 decreased from 86 percent to 72 percent when the forward Mach number was increased from 0.70 to 0.96."
Date: May 18, 1953
Creator: Evans, Albert J. & Liner, George
Item Type: Refine your search to only Report
open access

Influence of Hot-Working Conditions on High-Temperature Properties of a Heat-Resistant Alloy

Description: "The relationships between conditions of hot-working and properties at high temperatures and the influence of the hot-working on response to heat treatment were investigated for an alloy containing nominally 20 percent molybdenum, 2 percent tungsten, and 1 percent columbium. Commercially produced bar stock was solution-treated at 2,200 degrees F. to minimize prior-history effects and then rolled at temperatures of 2,200 degrees, 2,100 degrees, 2,000 degrees, 1,800 degrees, and 1,600 degrees F. … more
Date: May 20, 1955
Creator: Ewing, John F. & Freeman, J. W.
Item Type: Refine your search to only Report
open access

The Linearized Characteristics Method and Its Application to Practical Nonlinear Supersonic Problems

Description: "The methods of characteristics has been linearized by assuming that the flow field can be represented as a basic flow field determined by nonlinearized methods and a linearized superposed flow field that accounts for small changes of boundary conditions. The method has been applied to two-dimensional rotational flow where the basic flow is potential flow and to axially symmetric problems where conical flows have been used as the basic flows. In both cases the method allows the determination of… more
Date: July 24, 1951
Creator: Ferri, Antonio
Item Type: Refine your search to only Report
open access

Preliminary Investigation of a New Type of Supersonic Inlet

Description: "A supersonic inlet with supersonic deceleration of the flow entirely outside of the inlet is considered a particular arrangement with fixed geometry having a central body with a circular annular intake is analyzed, and it is shown theoretically that this arrangement gives high pressure recovery for a large range of Mach number and mass flow and, therefore, is practical for use on supersonic airplanes and missiles. Experimental results confirming the theoretical analysis give pressure recoverie… more
Date: 1952
Creator: Ferri, Antonio & Nucci, Louis M.
Item Type: Refine your search to only Report
open access

Investigation of Spoiler Ailerons for Use as Speed Brakes or Glide-Path Controls on Two NACA 65-Series Wings Equipped with Full-Span Slotted Flaps

Description: "A wind-tunnel investigation was made to determine the characteristics of spoiler ailerons used as speed brakes or glide-path controls on an NACA 65-210 wing and an NACA 65-215 wing equipped with full-span slotted flaps. Several plug aileron and retractable-aileron configurations were investigated on two wing models with the full-span flaps retracted and deflected.The results of this investigation have indicated that the use of plug or retractable ailerons, either alone or in conjunction with w… more
Date: 1951
Creator: Fischel, Jack & Watson, James M.
Item Type: Refine your search to only Report
open access

Effect of Aspect Ratio on the Low-Speed Lateral Control Characteristics of Untapered Low-Aspect-Ratio Wings Equipped With Flap and With Retractable Ailerons

Description: A low-speed wind-tunnel investigation was made to determine the lateral control characteristics of a series of untapered low-aspect-ratio wings. Sealed flap ailerons of various spans and spanwise locations were investigated on unswept wings of aspect ratios 1.13, 1.13, 4.13, and 6.13; and various projections of 0.60-semispan retractable ailerons were investigated on the unsweptback wings of aspect ratios 1.13, 2.13, and 4.13 and on a 45 degree sweptback wing. The retractable ailerons investigat… more
Date: February 8, 1952
Creator: Fischel, Jack; Naeseth, Rodger L.; Hagerman, John R. & O'Hare, William M.
Item Type: Refine your search to only Report
open access

Experimental determination of effects of frequency and amplitude on the lateral stability derivatives for a delta, a swept, and unswept wing oscillating in yaw

Description: "Three wing models were oscillated in yaw about their vertical axes to determine the effects of systematic variations of frequency and amplitude of oscillation on the in-phase and out-of-phase combination lateral stability derivatives resulting from this motion. The tests were made at low speeds for a 60 degree delta wing, a 45 degree swept wing, and an unswept wing; the swept and unswept wings had aspect ratios of 4. The results indicate that large changes in the magnitude of the stability der… more
Date: January 6, 1956
Creator: Fisher, Lewis R.
Item Type: Refine your search to only Report
open access

Ditching investigations of dynamic models and effects of design parameters on ditching characteristics

Description: From Summary: "Data from ditching investigations conducted at the Langley Aeronautical Laboratory with dynamic scale models of various airplanes are presented in the form of tables. The effects of design parameters on the ditching characteristics of airplanes, based on scale-model investigations and on reports of full-scale ditchings, are discussed. Various ditching aids are also discussed as a means of improving ditching behavior."
Date: November 16, 1956
Creator: Fisher, Lloyd J. & Hoffman, Edward L.
Item Type: Refine your search to only Report
open access

Investigation of a nonlinear control system

Description: A discontinuous variation of coefficients of the differential equation describing the linear control system before nonlinear elements are added is studied in detail. The nonlinear feedback is applied to a second-order system. Simulation techniques are used to study performance of the nonlinear control system and to compare it with the linear system for a wide variety of inputs. A detailed quantitative study of the influence of relay delays and of a transport delay is presented.
Date: October 18, 1957
Creator: Flügge-Lotz, I.; Taylor, C. F. & Lindberg, H. E.
Item Type: Refine your search to only Report
open access

Charts and approximate formulas for the estimation of aeroelastic effects of the lateral control of swept and unswept wings

Description: Charts and approximate formulas are presented for the estimation of static aeroelastic effects on the spanwise lift distribution, rolling-moment coefficient, and rate of roll due to the deflection of ailerons on swept and unswept wings at subsonic and supersonic speeds. Some design considerations brought out by the results of this report are discussed. This report treats the lateral-control case in a manner similar to that employed in NACA Report 1140 for the symmetric-flight case, and is inten… more
Date: 1953
Creator: Foss, Kenneth A. & Diederich, Franklin W.
Item Type: Refine your search to only Report
open access

Theoretical performance characteristics of sharp-lip inlets at subsonic speeds

Description: A method is presented for the estimation of the subsonic-flight-speed characteristics of sharp-lip inlets applicable to supersonic aircraft. The analysis, based on a simple momentum balance consideration, permits the computation of inlet-pressure-recovery mass-flow relations and additive-drag coefficients for forward velocities from zero to the speed of sound. The penalties for operation of a sharp-lip inlet at velocity ratios other than 1.0 may be severe; at lower velocity ratios an additive d… more
Date: 1954
Creator: Fradenburgh, Evan A. & Wyatt, DeMarquis D.
Item Type: Refine your search to only Report
open access

A Special Investigation to Develop a General Method for Three-Dimensional Photoelastic Stress Analysis

Description: The method of strain measurement after annealing is reviewed and found to be satisfactory for the materials available in this country. A new general method is described for the photoelastic determination of the principal stresses at any point of a general body subjected to arbitrary load. The method has been applied to a sphere subjected to diametrical compressive loads. The results show possibilities of high accuracy.
Date: 1953
Creator: Frocht, M. M. & Guernsey, R., Jr.
Item Type: Refine your search to only Report
open access

Effect of ground interference on the aerodynamic and flow characteristics of a 42 degree sweptback wing at Reynolds numbers up to 6.8 x 10(6)

Description: Report presents the results of an investigation of the effects of ground interference on the aerodynamic characteristics of a 42 degree sweptback wing at distances 0.68 and 0.92 of the mean aerodynamic chord from the simulated ground to the 0.25-chord point of the mean aerodynamic chord. Survey data behind the wing, both with and without the simulated ground, are presented in the form of contour charts of downwash, sidewash, and dynamic-pressure ratio at longitudinal stations of 2.0 and 2.8 mea… more
Date: December 17, 1954
Creator: Furlong, G. Chester & Bollech, Thomas V.
Item Type: Refine your search to only Report
open access

A summary and analysis of the low-speed longitudinal characteristics of swept wings at high Reynolds number

Description: An analysis of the longitudinal characteristics of swept wings which is based on available large-scale low-speed data and supplemented with low-scale data when feasible is presented. The emphasis has been placed on the differentiation of the characteristics by a differentiation between the basic flow phenomenon involved. Insofar as possible all large-scale data available as of August 15, 1951 have been summarized in tabular form for ready reference.
Date: May 14, 1952
Creator: Furlong, G. Chester & McHugh, James G.
Item Type: Refine your search to only Report
open access

An Investigation of the Maximum Lift of Wings at Supersonic Speeds

Description: This report presents the results of an exploratory investigation carried out in the Langley 9-inch supersonic tunnel to determine the maximum lift of wings operating at supersonic speeds. A variety of wing plan forms of random thickness distributions were tested at Mach numbers of 1.55, 1.90, and 2.32 and at Reynolds numbers varying between 0.74 x 10(6) and 0.27 x 10(6) at angles of attack ranging from zero up through the angle at which maximum lift occurred. Subsequent pressure-distribution te… more
Date: 1955
Creator: Gallagher, James J. & Mueller, James N.
Item Type: Refine your search to only Report
open access

A theoretical study of the effect of forward speed on the free-space sound-pressure field around propellers

Description: Report presenting an analysis of the sound-pressure field of a rotating propeller in forward flight in free space by replacing the normal-pressure distribution over the propeller associated with thrust and torque by a distribution of acoustic pressure doublets acting at the propeller disk. The result is presented for a moving and a fixed observer.
Date: 1954
Creator: Garrick, I. E. & Watkins, Charles E.
Item Type: Refine your search to only Report
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