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Interference effects of longitudinal flat plates on low-drag airfoils

Description: Three airfoils were tested with an intersecting flat plate normal to the span as a preliminary study of interference effects on airfoils. Small interference effects were noted on the first two airfoils, while larger effects were noted on the NACA 66,2-422 section, which had previously been shown to be unconservative with respect to separation. Airfoils known to be conservative should be used for inboard sections subject to nacelle and fuselage interference.
Date: November 1942
Creator: Abbott, Ira H.
open access

Pressure-Distribution Measurements of a Model of a Davis Wing Section with Fowler Flap Submitted by Consolidated Aircraft Corporation

Description: Wing pressure distribution diagrams for several angles of attack and flap deflections of 0 degrees, 20 degrees, and 40 degrees are presented. The normal force coefficients agree with lift coefficients obtained in previous test of the same model, except for the maximum lifts with flap deflection. Pressure distribution measurements were made at Reynolds Number of about 6,000,000.
Date: January 1942
Creator: Abbott, Ira H.
open access

Pressure-distribution measurements of two airfoil models with Fowler flaps submitted by Consolidated Aircraft Corporation as alternative wing sections of the XB-32 airplane

Description: Report presenting pressure distribution measurements on two 24-inch chord models equipped with Fowler flaps in the two-dimensional low-turbulence pressure tunnel. Results regarding pressure-distribution diagrams and normal-force and moment coefficients are provided.
Date: January 1942
Creator: Abbott, Ira H.
open access

Tests of four models representing intermediate sections of the XB-33 airplane including sections with slotted flap and ailerons

Description: Report presenting testing in the two-dimensional tunnel of four models submitted by the Glenn L. Martin Company as intermediate sections of the wing of the XB-33 airplane. Each airfoil model had different types of flaps or no flaps at all. Results regarding the lift and drag data, lift coefficients, effect of flap positions, aileron effects, drag coefficients, and hinge-moment coefficients are provided.
Date: June 1942
Creator: Abbott, Ira H.
open access

Tests of a Highly Cambered Low-Drag-Airfoil Section with a Lift-Control Flap, Special Report

Description: Tests were made in the NACA two-dimensional low turbulence pressure tunnel of a highly cambered low-drag airfoil (NACA 65,3-618) with a plain flap designed for lift control. The results indicate that such a combination offers attractive possibilities for obtaining low profile-drag coefficients over a wide range of lift coefficients without large reductions of critical speed.
Date: December 1942
Creator: Abbott, Ira H. & Miller, Ralph B.
open access

Aerodynamic Heat-Power Engine Operating on a Closed Cycle

Description: "Hot-air engines with dynamic compressors and turbines offer new prospects of success through utilization of units of high efficiencies and through the employment of modern materials of great strength at high temperature. Particular consideration is given to an aerodynamic prime mover operating on a closed circuit and heated externally. Increase of the pressure level of the circulating air permits a great increase of limit load of the unit. This also affords a possibility of regulation for whic… more
Date: November 1942
Creator: Ackeret, J. & Keller, D. C.
open access

A method for calculating heat transfer in the laminar flow region of bodies

Description: Report presenting a practical method for determining the chordwise distribution of the rate of heat transfer from the surface of a wing or body of revolution to air. The method is limited to use to the determination of heat transfer fro the forward section of such bodies when the flow is laminar.
Date: December 1942
Creator: Allen, H. Julian & Look, Bonne C.
open access

Tensile and Pack Compressive Tests of Some Sheets of Aluminum Alloy, 1025 Carbon Steel, and Chromium-Nickel Steel

Description: "Tensile and compressive stress-strain curves, stress-deviation curves, and secant modulus-stress curves are given for longitudinal and transverse specimens of 17S-T, 24S-T, and 24S-RT aluminum-alloy sheet in thicknesses from 0.032 to 0.081 inch, 1025 carbon steel sheet in thicknesses of 0.054 and 0.120 inch, and chromium-nickel steel sheet in thicknesses form 0.020 to 0.0275 inch. Significant differences were found between the tensile and the compressive stress-strain curves, and also the corr… more
Date: February 1942
Creator: Atchison, C. S. & Miller, James A.
open access

A theoretical analysis of the effect of aileron inertia and hinge moment on the maximum rolling acceleration of airplanes in abrupt aileron rolls

Description: Report presenting data on the rolling accelerations of airplanes of different types and sizes in abrupt aileron rolls in connection with a number of maneuverability and flying qualities investigations. An analysis was made to determine the relation between the torque applied to the aileron system by the pilot, the motion of the system, and the subsequent rolling motion of the airplane in abrupt aileron roll.
Date: February 1942
Creator: Bailey, F. J., Jr. & O'Sullivan, William J.
open access

Flight investigation of the performance and cooling characteristics of a long-nose high-inlet-velocity cowling on the XP-42 airplane

Description: Report presenting the results of a series of flight tests of the maximum speed and cooling characteristics in high-speed level flight and in climb of the XP-42 airplane equipped with a long-nose high-inlet-velocity cowling. The results indicated that a maximum speed of 338 miles per hour at 870 horsepower at 17,000 feet was achievable, which is above the engine critical altitude. Pressure measurements in the entrances in the cylinder baffles showed a uniform distribution of pressure on the fron… more
Date: April 1942
Creator: Bailey, F. J., Jr.; Johnston, J. Ford & Voglewede, T. J.
open access

Effect of Changes in Aspect Ratio, Side Area, Flight-Path Angle, and Normal Acceleration on Lateral Stability

Description: Report presenting computations made to determine the effect of changes in wing aspect ratio, additional side area, flight-path angle, and normal acceleration on the relation between the fin area and the dihedral angle required for spiral and for oscillatory lateral stability for a hypothetical airplane of the pursuit or fighter categories. The diagrams indicate that the effect of wing aspect ratio on lateral stability is small.
Date: December 1942
Creator: Bamber, M. J.
open access

High-speed tests of radial-engine nacelles on a thick low-drag wing

Description: Report presenting testing in the high-speed wind tunnel to determine the drag characteristics of several types of radial-engine nacelle on a low-drag airfoil. The drag coefficients of nacelles incorporating cowling-nose shapes shown by previous tests to be efficient and afterbodies of adequate length were about the same magnitude as commonly obtained for comparable installations on conventional wings. Results regarding the reduction of data, effect of nacelles on lift, and pressures at wing-nac… more
Date: May 1942
Creator: Becker, John V.
open access

Analysis of Heat and Compressibility Effects in Internal Flow Systems and High-Speed Tests of a Ram-Jet System

Description: Report presenting an analysis of the effects of heat and compressibility in the flow through the internal systems of aircraft. Equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
Date: September 1942
Creator: Becker, John V. & Baals, Donald D.
open access

Analysis of Heat and Compressibility Effects in Internal Flow Systems and High-Speed Tests of a Ram-Jet System

Description: Report discussing an analysis has been made by the NACA of the effects of heat and compressibility in the flow through the internal systems of aircraft along with equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
Date: July 21, 1942
Creator: Becker, John V. & Baals, Donald D.
open access

High-Speed Tests of a Ducted Body with Various Air-Outlet Openings

Description: Test of a ducted body with Internal flow were made in the 8-foot high-speed wind tunnel for the purpose of studying the effects on external drag and an critical speed of the addition of efficient inlet and outlet openings to a basic streamline shape. Drag tests of a 13.6- inch-diameter streamline body of fineness ratio 6.14 were made at Mach numbers ranging from 0.20 to 0.75. The model was centrally mounted on a 9-percent-thick airfoil and was designed to have an efficient airfoil-body juncture… more
Date: May 1942
Creator: Becker, John V. & Baals, Donald D.
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.
open access

A Preliminary Investigation of the Characteristics of Air Scoops on a Fuselage

Description: Report presenting an investigation of the characteristics of air scoops in the NACA propeller-research tunnel. The investigation showed that, at inlet-velocity ratios equal to or greater than 0.3, scoops in a forward position on the fuselage gave total pressures in the inlet nearly equal to free-stream total pressure.
Date: December 1942
Creator: Bell, E. Barton & DeKoster, Lucas J.
open access

Test of a Dual-Rotation Axial-Flow Fan

Description: Report presenting a dual-rotation axial-flow fan composed of two oppositely rotating 24-blade rotors. The fan was tested with various combinations of front and rear blade angles and with two combinations of front and rear solidities. For quantity coefficients above 0.3 the greatest pressure rise was obtained from 24 blades in each rotor with the blades adjusted to absorb equal torque at maximum pressure.
Date: December 1942
Creator: Bell, E. Barton & DeKoster, Lucas J.
open access

The Porpoising Characteristics of a Planing Surface Representing the Forebody of a Flying-Boat Hull

Description: Porpoising characteristics were observed on V-body fitted with tail surfaces for different combinations of load, speed, moment of inertia, location of pivot, elevator setting, and tail area. A critical trim was found which was unaltered by elevator setting or tail area. Critical trim was lowered by moving pivot either forward or down or increasing radius or gyration. Increase in mass and moment of inertia increased amplitude of oscillations. Complete results are tabulated and shown graphically.
Date: May 1942
Creator: Benson, James M.
open access

An Investigation of Hydrofoils in the NACA Tank 1: Effect of Dihedral and Depth of Submersion

Description: Tests were conducted on hydrofoil assemblies approximating an arrangement for use under seaplanes or surface boats. A series of hydrofoils, each supported by two struts, was towed at various depths ranging from partial submersions to a depth of 5-chord lengths. At depths greater than 4 or 5 chords, the influence of the surface of the water is small; hydrofoils operating at low speed will have characteristics similar to those of airfoils of the same section.
Date: September 1942
Creator: Benson, James M. & Land, Norman S.
open access

The effect of dead rise upon the low-angle type of porpoising

Description: Report presenting data pertaining to forces and moments developed by V-bottom planing surfaces of different angles of dead rise in order to compute the effect of dead rise on the lower trim limit of stability on a seaplane. Increase of angle of dead rise in the range of 10 degrees to 30 degrees causes an important increase in the lower limit of stability.
Date: October 1942
Creator: Benson, James M. & Lina, Lindsay J.
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