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NACA Conference on Aircraft Loads, Structures, and Flutter

Description: This document contains reproductions of technical papers on some of the most recent research results on aircraft loads, flutter, and structures from the NACA laboratories. These papers were presented by members of the staff of the NACA laboratories at the Conference held at the Langley Aeronautical Laboratory March 5, 6, and 7, 1957. The primary purpose of this Conference was to convey to contractors of the military services and others concerned with the design of aircraft these recent research results and to provide those attending an opportunity to discuss the results. The papers in this document are in the same form in which they were presented at the Conference in order to facilitate their prompt distribution. The original presentation and this record are considered as complementary to, rather than as substitutes for, the Committee?s more complete and formal reports. Accordingly, if information from this document is utilized it is requested that this document not be listed as a reference. Individual reports dealing with most of the information presented at the Conference will subsequently be published by NACA and will therefore be suitable as reference material.
Date: March 5, 1957
Partner: UNT Libraries Government Documents Department

NACA: University Conference on Aerodynamics, A Compilation of the Papers Presented

Description: This document contains reproductions of the technical papers presented at the NACA - University Conference on Aerodynamics held at the Langley Aeronautical Laboratory on June 21, 22, and 23, 1948. The conference was held in recognition of the difficulties, imposed by security restrictions, in keeping abreast of the rapid advances in aerodynamics. The papers were prepared to review the status of a number of fields of interest, to summarize the more important wartime advances that are no longer classified, and to orient reference material for further study. The papers in this document are in the same form in which they were presented at the conference so that distribution of them might be prompt. The original presentation and this record are considered as complementary to, rather than as substitutes for, the Committee?s system of complete and formal reports.
Date: 1948-06-21/1948-06-23
Partner: UNT Libraries Government Documents Department

Summary of Section Data on Trailing-Edge High-Lift Devices

Description: A summary has been made of available data on the characteristics of airfoil sections with trailing-edge high-lift devices. Data for plain, split, and slotted flaps are collected and analyzed. The effects of each of the variables involved in the design of the various types of flap are examined and, in cases where sufficient data are given, optimum configurations are deduced. Wherever possible, the effects of airfoil section, Reynolds number, and leading-edge roughness are shown. For single and double slotted flaps, where a great mass of unrelated date are available, maximum lift coefficients of a large number of configurations are presented in tables.
Date: August 20, 1948
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Bodies at Supersonic Speeds: A Collection of Three Papers

Description: The three papers collected here are: 'The Effect of Nose Shape on the Drag of Bodies of Revolution at Zero Angle of Attack.', 'Base Pressure on Wings and Bodies with Turbulent Boundary Layers', and 'Flow over Inclined Bodies'. The subject of the first paper is the drag of the nose section of bodies of revolution at zero angle of attack. The main object of the second paper is to summarize the prinicpal results of the many wind tunnel and free flight measurements of base pressure on both bodies of revolution and blunt trailing edge airfoils.
Date: November 9, 1951
Partner: UNT Libraries Government Documents Department

Pressure Distribution Measurements on a Turbine Rotor Blade Passing Behind a Turbine Nozzle Lattice

Description: As a turbine rotor turns, the blades traverse the wake zones of the nozzle vanes. A periodic fluctuation of the pressure distribution around the circumference of the rotor blade is therefore caused. It was desired to investigate quantitatively this effect. At the same time, the magnitude of the force acting upon one profile of the rotor-blade lattice at various positions of this lattice relative to the nozzle lattice was to be determined.
Date: September 1, 1947
Creator: Hausenblas
Partner: UNT Libraries Government Documents Department

Flight Studies of the Horizontal-Tail Loads Experienced by a Fighter Airplane in Abrupt Maneuvers

Description: Field measurements were made on a fighter airplane to determine the approximate magnitude of the horizontal tail loads in accelerated flight. In these flight measurements, pressures at a few points were used as an index of the tail loads by correlating these pressures with complete pressure-distribution data obtained in the NACA full-scale tunnel. In addition, strain gages and motion pictures of tail deflections were used to explore the general nature and order of magnitude of fluctuating tail loads in accelerated stalls.
Date: January 1, 1944
Partner: UNT Libraries Government Documents Department

NACA Conference on Aerodynamics of High Speed Aircraft

Description: This document contains reproductions of technical papers presented by staff members of the NACA Laboratories at the NACA Conference on Aerodynamics of High-Speed Aircraft held at the Langley Aeronautical Laboratory November 1, 2, and 3, 1955. The primary purpose of the conference was to convey to contractors of the military services and others concerned with the design of aircraft the results of recent research and to provide those attending with an opportunity to discuss these results. The papers in this document are in the same form in which they were orally presented at the conference to facilitate their prompt distribution. The original presentation and this record are considered as complementary to, rather than as substitutes for, the Committee's more complete and formal reports.
Date: November 1, 1955
Partner: UNT Libraries Government Documents Department

Flight tests at supersonic speeds to determine the effect of taper on the zero-lift drag of sweptback low-aspect-ratio wings

Description: Report presenting testing using rocket-powered models to provide an experimental comparison with linearized theoretical calculations for zero-lift drag of sweptback tapered wings with thin, symmetrical, double-wedge airfoil sections. The theory compared favorably with experimental results over most of the test range. Taper was generally found to increase wing drag at low supersonic speeds but reduced drag at higher speeds.
Date: September 5, 1950
Creator: Pittel, Murray
Partner: UNT Libraries Government Documents Department

A preliminary study of machine-countersunk flush rivets subjected to a combined static and alternating shear load

Description: Report discusses the results of an investigation to study the effect of the height of a rivet head on the number of cycles required to cause failure of a machine-countersunk flush-riveted joint under a combined static and alternating shear load. A tight joint and a loose joint were tested and the number of cycles to failure and location of fatigue failure were compared.
Date: December 1943
Creator: Crate, Harold
Partner: UNT Libraries Government Documents Department

A low-speed experimental study of the directional characteristics of a sharp-nosed fuselage through a large angle-of-attack range at zero angle of sideslip

Description: Report presenting an investigation to determine the directional characteristics of a sharp-nosed fuselage through a large angle-of-attack range at zero angle of sideslip. The fuselage was found to experience a large increase in yawing moment as the angle of attack increases. The results also indicated that a ring or other roughness used on the nose caused a large decrease in the yawing moment obtained at high angles of attack.
Date: November 19, 1952
Creator: Letko, William
Partner: UNT Libraries Government Documents Department

Measurement of static pressure on aircraft

Description: From Summary: "Existing data on the errors involved in the measurement of static pressure by means of static-pressure tubes and fuselage vents are presented. The errors associated with the various design features of static-pressure tubes are discussed for the condition of zero angle of attack and for the case where the tube is included to the flow. Errors due to variations in the configuration of static-pressure vents are also presented."
Date: April 1, 1957
Creator: Gracey, William
Partner: UNT Libraries Government Documents Department

Exploratory investigation of transpiration cooling of a 40 degree double wedge using nitrogen and helium as coolants at stagnation temperatures of 1,295 to 2,910 degrees F

Description: Report presenting an investigation of transpiration cooling in a preflight jet model consisting of a double wedge of 40 degrees included angle with a porous stainless-steel specimen inserted flush with the top surface of the wedge. Nitrogen and helium were used as coolants and testing was conducted for flow rates ranging from about 0.03 to 0.30 percent of the local weight flow. The helium coolant required only about one-fourth to one-fifth the coolant flow weight as the nitrogen coolant for the same amount of heat-transfer reduction.
Date: August 1, 1957
Creator: Rashis, Bernard
Partner: UNT Libraries Government Documents Department

Full-scale-tunnel performance tests of the PV-2 helicopter rotor

Description: Report discussing basic performance data obtained on the PV-2 helicopter rotor. Blade motion, rotor forces, and power were measured for static-thrust condition and a limited range of forward-flight conditions. Recommendations are provided for further testing to obtain blade-motion data and force-test data in order to develop a more detailed analysis.
Date: April 1945
Creator: Migotsky, Eugene
Partner: UNT Libraries Government Documents Department

The aerodynamic effects of wing cut-outs

Description: From Introduction: "The information now available concerning wing cut-outs or applicable to the analysis of their effects is plentiful (references 1 to 7) but too disconnected and unorganized to be of the greatest possible usefulness. In connection with the interference program being conducted in the N.A.C.A. varible-density wind tunnel, an analysis was therefore made of existing material to determine the qualitative effects of the different features of wing cut-outs, and to obtain means of calculating wing characteristics as affected by them."
Date: 1934
Creator: Sherman, Albert
Partner: UNT Libraries Government Documents Department

An analytical investigation of the effect of the rate of increase of turbulent kinetic energy in the stream direction on the development of turbulent boundary layers in adverse pressure gradients

Description: From Introduction: "The purpose of this paper is to provide a derivation of the general integral form of the boundary equation without neglecting the Reynolds normal-stress term. Two special cases of this equation are given explicitly."
Date: November 1, 1953
Creator: Rashis, Bernard
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a two-blade NACA 10-(3)(062)-045 propeller and of a two-blade NACA 10-(3)(08)-045 propeller

Description: Report discussing characteristics are given for the two-blade NACA 10-(3)(062)-045 propeller and for the two-blade NACA 10-(3)(08)-045 propeller over a range of advance ratio from 0.5 to 3.8, through a blade-angle range from 20 degrees to 55 degrees measured at the 0.75 radius. Maximum efficiencies of the order of 91.5 to 92 percent were obtained for the propellers. The propeller with the thinner airfoil sections over the outboard portion of the blades, the NACA 10-(3)(062)-045 propeller, had lower losses at high tip speeds, the difference amounting to about 5 percent at a helical tip Mach number of 1.10.
Date: January 1953
Creator: Solomon, William
Partner: UNT Libraries Government Documents Department

Completed Tabulation in the United States of Tests of 24 Airfoils at High Mach Numbers (Derived from Interrupted Work at Guidonia, Italy in the 1.31- by 1.74-Foot High-Speed Tunnel)

Description: Two-dimensional data were obtained in Mach range of from 0.40 to 0.94 and Reynolds Number range of (3.4 - 4.2) X 10 Degrees. Results indicate that thickness ratio is dominating shape parameter at high Mach numbers and that aerodynamic advantages are attainable by using thinnest possible sections. Effects of jet boundaries, Reynolds Number, and Data presented are free from jet-boundary and humidity effects.
Date: June 1, 1945
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department

Analysis of factors affecting net lift increment attainable with trailing-edge split flaps on tailless airplanes

Description: From Introduction: "The lift increments of different flap arrangements were determined by the method of reference 1 with a simple chord correction factor being applied. This procedure is somewhat similar in basic principles to the method of reference 2. The accuracy of the present method was determined by calculating by means of this method the lift and moment increments of flaps on 10 different finite wing-flap combinations for which wind-tunnel data were available."
Date: September 1944
Creator: Maggin, Bernard
Partner: UNT Libraries Government Documents Department

Analysis of 2-spar cantilever wings with special reference to torsion and load transference

Description: From Summary: "This paper deals with the analysis of 2-spar cantilever wings in torsion, taking cognizance of the fact that the spars are not independent, but are interconnected by ribs and other structural members. The principles of interaction are briefly explained, showing that the mutual relief action occurring depends on the "pure torsional stiffness" of the wing cross section. Various practical methods of analysis are outlined."
Date: January 1, 1936
Creator: Kuhn, Paul
Partner: UNT Libraries Government Documents Department

An analysis of airspeeds attained by a Douglas DC-4 airplane in commercial operations during the early months of 1947

Description: Report presenting airspeed and altitude data for nonscheduled cargo operations of a Douglas DC-4 airplane between Seattle, Washington and Alaska during February and March of 1947 to determine the probability of reaching or exceeding given values of airspeed and Mach number. The total probability of exceeding a placard never-exceed speed of 266 mph depends primarily on exceeding the speed in descent. The probability was found to be about once in 100 hours of descent or once in 1000 hours of general flying time.
Date: October 6, 1949
Creator: Steiner, Roy
Partner: UNT Libraries Government Documents Department