Month

Application of the wire-mesh plotting device to incompressible cascade flows (open access)

Application of the wire-mesh plotting device to incompressible cascade flows

From Summary: "The methods used in the application of the wire-mesh plotting device to find the flow pattern about a cascade of airfoils in compressible inviscid flow and some mathematical checks that increase the accuracy of this application are described. Results for two typical turbine-blade cascades are shown to compare well with experimental data. A method of utilizing the wire mesh to design turbine blades with a prescribed pressure distribution in incompressible flow is presented."
Date: May 1950
Creator: Westphal, Willard R. & Dunavant, James C.
System: The UNT Digital Library
A Comparison of the Lateral Controllability with Flap and Plug Ailerons on a Sweptback-Wing Model (open access)

A Comparison of the Lateral Controllability with Flap and Plug Ailerons on a Sweptback-Wing Model

Note presenting an investigation to compare the dynamic lateral control characteristics provided by step plug ailerons with those provided by conventional flap ailerons on a sweptback-wing model. The model used had a 38 degree sweptback wing with an aspect ratio of 3 and a taper ratio of 0.5.
Date: May 1950
Creator: Lovell, Powell M., Jr. & Stassi, Paul P.
System: The UNT Digital Library
Comparison of theoretical and experimental heat transfer on a cooled 20 degrees cone with a laminar boundary layer at a Mach number of 2.02 (open access)

Comparison of theoretical and experimental heat transfer on a cooled 20 degrees cone with a laminar boundary layer at a Mach number of 2.02

Report presenting heat-transfer measurements on an air-cooled 20 degree cone with a laminar boundary layer at Mach number 2.02. The surface temperature in the instrumented area on the cone was essentially constant at all test conditions, but the area was preceded by severe surface-temperature gradients.
Date: May 1950
Creator: Scherrer, Richard & Gowen, Forrest E.
System: The UNT Digital Library
Correlation of physical properties with molecular structure for dicyclic hydrocarbons : I -2-n-alkylbiphenyl, 1,1-diphenylalkane,a,w-diphenylalkane; 1,1-dicyclohexylalkane, and a,w-dicyclohexylalkane series (open access)

Correlation of physical properties with molecular structure for dicyclic hydrocarbons : I -2-n-alkylbiphenyl, 1,1-diphenylalkane,a,w-diphenylalkane; 1,1-dicyclohexylalkane, and a,w-dicyclohexylalkane series

Report presenting a study of the correlation between molecular structure and physical properties of high-density hydrocarbons, including the net heat of combustion, melting point, boiling point, density, and kinematic viscosity. They are evaluated for their use as a fuel, especially in planes that are required to have smaller fuel tanks.
Date: May 1950
Creator: Wise, Paul H.; Serijan, Kasper T. & Goodman, Irving A.
System: The UNT Digital Library
Dynamics of a turbojet engine considered as a quasi-static system (open access)

Dynamics of a turbojet engine considered as a quasi-static system

Report presenting a determination of the dynamic characteristics of a typical turbojet engine with a centrifugal compressor, a sonic-flow turbine-nozzle diaphragm, and a fixed-area exhaust nozzle. Results indicate that a linear differential equation for engine acceleration as a function of fuel flow and engine speed for operation near a steady-state operating condition can be written.
Date: May 1950
Creator: Otto, Edward W. & Taylor, Burt L., III
System: The UNT Digital Library
The effects of amount and type of camber on the variation with Mach number of the aerodynamic characteristics of a 10-percent-thick NACA 64A- series airfoil section (open access)

The effects of amount and type of camber on the variation with Mach number of the aerodynamic characteristics of a 10-percent-thick NACA 64A- series airfoil section

Report presenting the results of a wind-tunnel investigation to determine the effect of varying the amount and type of camber on the section characteristics of 10-percent-chord-thick NACA 64A-series profiles. Results regarding lift- and drag-divergence characteristics, lift characteristics, drag characteristics, and pitching-moment characteristics are provided.
Date: May 1950
Creator: Summers, James L. & Treon, Stuart L.
System: The UNT Digital Library
The effects of stability of spin-recovery tail parachutes on the behavior of airplanes in gliding flight and in spins (open access)

The effects of stability of spin-recovery tail parachutes on the behavior of airplanes in gliding flight and in spins

Note presenting an investigation with airplane models in the free-flight and 20-foot free-spinning tunnels to determine whether a stable parachute could be safely towed behind an airplane in flight and whether it would be effective as a spin-recovery device. Results regarding the parachute characteristics, behavior in gliding flight, spin-recovery effectiveness, and effect of increasing towline length are provided.
Date: May 1950
Creator: Scher, Stanley H. & Draper, John W.
System: The UNT Digital Library
Evaluation of Several Adhesives and Processes for Bonding Sandwich Constructions of Aluminum Facings on Paper Honeycomb Core (open access)

Evaluation of Several Adhesives and Processes for Bonding Sandwich Constructions of Aluminum Facings on Paper Honeycomb Core

Note presenting testing of bonding processes evaluated by tension tests on sandwich specimens of 1-inch aluminum cubes bonded to a resin-impregnated paper honeycomb core. 6 of the 14 processes gave good-quality bonds which had average strengths of more than 350 psi or more than 75-percent failure in the core when tested at two different temperatures.
Date: May 1950
Creator: Eickner, H. W.
System: The UNT Digital Library
Experiments in External Noise Reduction of Light Airplanes (open access)

Experiments in External Noise Reduction of Light Airplanes

This note is part of a program with the objective of finding practical ways of reducing the external noise level of light airplanes in order to make them less objectionable to people on the ground. The current report covers noise measurements on standard light airplanes and on similar airplanes equipped with engine mufflers, propeller reduction gears, and propellers with various numbers of blades and blade shapes. The results indicate that reductions in noise level were found to result from muffling the engine and from reducing propeller tip speed and blade loading.
Date: May 1950
Creator: Beranek, Leo L.; Elwell, Fred S.; Roberts, John P. & Taylor, C. Fayette
System: The UNT Digital Library
Formulas and Charts for the Supersonic Lift and Drag of Flat Swept-Back Wings With Interacting Leading and Trailing Edges (open access)

Formulas and Charts for the Supersonic Lift and Drag of Flat Swept-Back Wings With Interacting Leading and Trailing Edges

Note presenting formulas and design charts for the lift in cases for wings with rectilinear plan forms swept so that both leading and trailing edges lie within their respective Mach cones. The charts cover a practical range of aspect ratios and plan forms of moderate taper, with tips parallel to the stream. Numerical results and an application of the charts are included.
Date: May 1950
Creator: Cohen, Doris
System: The UNT Digital Library
Further Experimental Studies of Area Suction for the Control of the Laminar Boundary Layer on a Porous Bronze NACA 64A010 Airfoil (open access)

Further Experimental Studies of Area Suction for the Control of the Laminar Boundary Layer on a Porous Bronze NACA 64A010 Airfoil

Note presenting a low-turbulence wind-tunnel investigation of an NACA 64A010 airfoil with a porous surface to determine the reduction in section total-drag coefficient that might be obtained at large Reynolds numbers by the use of area suction. This report primarily deals with additional tests of the same airfoil model equipped with a porous skin of lower porosity.
Date: May 1950
Creator: Braslow, Albert L. & Visconti, Fioravante
System: The UNT Digital Library
Further experimental studies of area suction for the control of the laminar boundary layer on a porous bronze NACA 64A010 airfoil (open access)

Further experimental studies of area suction for the control of the laminar boundary layer on a porous bronze NACA 64A010 airfoil

Report presenting a low-turbulence wind-tunnel investigation of an NACA 64A010 airfoil with a porous surface to determine the reduction in section total-drag coefficient that can be obtained at large Reynolds numbers by using area suction. While previous testing has been reported on, the focus of this paper is primarily the results of additional tests of the same airfoil model equipped with a porous skin of lower porosity.
Date: May 1950
Creator: Braslow, Albert L. & Visconti, Fioravante
System: The UNT Digital Library
Hovering and Low-Speed Performance and Control Characteristics of an Aerodynamic-Servocontrolled Helicopter Rotor System as Determined on the Langley Helicopter Tower (open access)

Hovering and Low-Speed Performance and Control Characteristics of an Aerodynamic-Servocontrolled Helicopter Rotor System as Determined on the Langley Helicopter Tower

Report presenting an investigation to obtain basic performance and control characteristics of an aerodynamic-servocontrolled rotor system. Results regarding the hovering performance, low-speed flight performance, control effectiveness, transient response to collective pitch, and transient response to cyclic pitch are provided.
Date: May 1950
Creator: Carpenter, Paul J. & Paulnock, Russell S.
System: The UNT Digital Library
An improved approximate method for calculating lift distributions due to twist (open access)

An improved approximate method for calculating lift distributions due to twist

Report presenting a method for calculating the lift distribution due to twist which gives a closer approximation than the current Schrenk empirical method and requires about the same amount of computing. The method uses the lifting-line theory and makes use of the lift distribution due to angle of attack and considers the aspect ratio of the wing. Examples are presented for four main types of twist: symmetrical, antisymmetrical, continuous, and discontinuous.
Date: May 24, 1950
Creator: Sivells, James C.
System: The UNT Digital Library
Improvement of high-temperature properties of magnesium-cerium forging alloys (open access)

Improvement of high-temperature properties of magnesium-cerium forging alloys

Report presenting an investigation to obtain an improvement in the high-temperature properties and resistance to creep of magnesium-cerium forging alloys. Preliminary testing was carried out to determine the most optimum alloy and then further testing was carried out on different heats of magnesium containing various amounts of cerium.
Date: May 1950
Creator: Grube, K.; Davis, J. A.; Eastwood, L. W.; Lorig, C. H. & Cross, H. C.
System: The UNT Digital Library
Investigation of spark-over voltage - density relation for gas-temperature sensing (open access)

Investigation of spark-over voltage - density relation for gas-temperature sensing

Report presenting the relation of spark-over voltage to gas density as a basis for a possible gas-temperature-sensing method. The investigation indicated that application of the spark-discharge mechanism to a gas-temperature-sensing method is feasible. Results regarding the types of electrode and effect of humidity, effect of cathode material, surface roughness, effect of gas velocity, effect of radiant energy, gas composition, effect of thermal expansion, miscellaneous effects, and reproducibility of spark-over voltage are provided.
Date: May 1950
Creator: Koenig, Robert J. & Cesaro, Richard S.
System: The UNT Digital Library
Maximum pitching angular accelerations of airplanes measured in flight (open access)

Maximum pitching angular accelerations of airplanes measured in flight

Report presenting a compilation of flight test data on pitching angular accelerations. An analysis of the data was also made to establish methods for determining maximum pitching accelerations.
Date: May 1950
Creator: Matheny, Cloyce E.
System: The UNT Digital Library
Performance and Load-Range Characteristics of Turbojet Engine in Transonic Speed Range (open access)

Performance and Load-Range Characteristics of Turbojet Engine in Transonic Speed Range

Note presenting an analysis of the performance and load-range characteristics of the turbojet engine for various flight speeds, altitudes, compressor pressure ratios, and turbine-inlet temperatures. The values of the lift-drag and structure-to-gross-weight ratios of the aircraft and the efficiencies of the engine components assumed for this analysis are representative of the best values obtained either in practice or in laboratory investigations. Results regarding engine performance, load-range characteristics, and effect of changes in engine weight and airplane characteristics are provided.
Date: May 1950
Creator: Lubarsky, Bernard
System: The UNT Digital Library
A Review of Information on the Mechanical Properties of Aluminum Alloys at Low Temperatures (open access)

A Review of Information on the Mechanical Properties of Aluminum Alloys at Low Temperatures

Report presenting the available sources of data on the mechanical properties of aluminum alloys at low temperatures and a summary of the material to be found in each source. General conclusions regarding commercially available aluminum alloys are also provided.
Date: May 1950
Creator: Bogardus, K. O.; Stickley, G. W. & Howell, F. M.
System: The UNT Digital Library
Review of Literature Pertinent to Fire-Extinguishing Agents and to Basic Mechanisms Involved in Their Action (open access)

Review of Literature Pertinent to Fire-Extinguishing Agents and to Basic Mechanisms Involved in Their Action

Note presenting a review of literature relating to fire-extinguishing agents in order to ascertain the extent of present knowledge and to determine what research might lead to the development of more efficient agents for extinguishing fires in aircraft. An analysis of the extinguishing data was made in order to determine the relative extinguishing effectiveness of different substances and the basic mechanisms involved in the action of extinguishing agents.
Date: May 1950
Creator: Fryburg, George
System: The UNT Digital Library
Stress-Strain and Elongation Graphs for Alclad Aluminum-Alloy 24S-T86 Sheet (open access)

Stress-Strain and Elongation Graphs for Alclad Aluminum-Alloy 24S-T86 Sheet

Note presenting results of tests on duplicate longitudinal and transverse specimens of Alclad aluminum alloy 24S-T86 sheets with three nominal thicknesses. The stress-strain and stress-deviation graphs are plotted on a dimensionless basis to make them applicable to sheets of the alloy with yield strengths which differ from those of the test specimens.
Date: May 1950
Creator: Miller, James A.
System: The UNT Digital Library
Theoretical analysis of various thrust-augmentation cycles for turbojet engines (open access)

Theoretical analysis of various thrust-augmentation cycles for turbojet engines

Report presenting the results of analytical studies of tail-pipe-burning, water-injection, and bleedoff methods of thrust augmentation that provide an insight into the operating characteristics and summarize the performance that may be obtained when applied to a typical turbojet engine. Results regarding bleedoff and water-injection rates, performance of the primary engine, and performance of the secondary engine, performance of the complete engine are provided.
Date: May 1950
Creator: Lundin, Bruce T.
System: The UNT Digital Library
Theoretical lift and damping in roll of thin wings with arbitrary sweep and taper at supersonic speeds: supersonic leading and trailing edges (open access)

Theoretical lift and damping in roll of thin wings with arbitrary sweep and taper at supersonic speeds: supersonic leading and trailing edges

Report presenting generalized expressions obtained by means of the linearized theory for the surface velocity potentials and the surface-pressure distributions due to lift and roll, the lift-curve slope, and the damping-in-roll derivative for a series of thin wings. The results of the investigation are presented in the form of generalized design curves for rapid estimation of the derivatives.
Date: May 1950
Creator: Harmon, Sidney M. & Jeffreys, Isabella
System: The UNT Digital Library