Critical Compressive Stress for Outstanding Flanges (open access)

Critical Compressive Stress for Outstanding Flanges

"A chart is presented for the values of the coefficient in the formula for the critical compressive stress at which buckling may be expected to occur in outstanding flanges. These flanges are flat rectangular plates supported along the Loaded edges, supported and elastically restrained along one unloaded edge, and free along the other unloaded edge. The mathematical derivations of the formulas required for the construction of the chart are given" (p. 1).
Date: April 1941
Creator: Lundquist, Eugene E. & Stowell, Elbridge Z.
System: The UNT Digital Library
Propeller-Design Problems of High-Speed Airplanes, Special Report (open access)

Propeller-Design Problems of High-Speed Airplanes, Special Report

"It is shown that on the basis of existing high-speed airfoil data, propeller efficiencies appreciably in excess of 40% do not appear possible at speeds above 500 miles per hour at 20,000 feet. The assumption that present propeller-blade thicknesses cannot be reduced radically, is implied. Until the reliability and applicability of the airfoil data are established, this conclusion must not be regarded as infallible. Dive tests with airplanes equipped with thrust meters and torque meters are proposed to provide an urgently needed check" (p. 1).
Date: April 1941
Creator: Dickinson, H. B.
System: The UNT Digital Library
High-Speed Tests of a Model Twin-Engine Low-Wing Transport Airplane (open access)

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

"Force tests were made of a 1/8-scale model of a twin-engine low-wing transport airplane in the NACA 8-foot high-speed wind tunnel to investigate compressibility and interference effects at 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. The results show serious increases in drag at critical speeds below 450 miles per hour due to the occurrence of compressibility burbles on the standard radial-engine cowlings, on sections of the wing as a result of wing-nacelle interference, and on the semi-retracted main landing wheels" (p. 1).
Date: April 1940
Creator: Becker, John V. & Leonard, Lloyd H.
System: The UNT Digital Library
High-Speed Tests of Radial-Engine Cowlings (open access)

High-Speed Tests of Radial-Engine Cowlings

The drag characteristics of eight radial-engine cowlings have been determined over a wide speed range in the N.A.C.A. 8-foot high-speed wind tunnel. The pressure distribution over all cowlings was measured, to and above the speed of the compressibility burble, as an aid in interpreting the force tests. One-fifth-scale models of radial-engine cowlings on a wing-nacelle combination mere used in the tests.
Date: April 1939
Creator: Robinson, Russell G. & Becker, John V.
System: The UNT Digital Library
Energy Loss, Velocity Distribution, and Temperature Distribution for a Baffled Cylinder Model, Special Report (open access)

Energy Loss, Velocity Distribution, and Temperature Distribution for a Baffled Cylinder Model, Special Report

Report discusses the important principles involved in the operation of a baffle for an engine cylinder and how using a correctly designed baffle can improve cooling. The baffle-exit radius and width and exit-duct length were found to be the most important parts of the baffle and a baffle that gave a relatively uniform temperature distribution was designed.
Date: April 1937
Creator: Brevoort, Maurice J.
System: The UNT Digital Library
Notes on Factors Affecting Geometrical Arrangement of Tricycle-Type Landing Gears (open access)

Notes on Factors Affecting Geometrical Arrangement of Tricycle-Type Landing Gears

The effects of the geometrical arrangement of tricycle landing gears on various characteristics of an airplane equipped with such landing gear is discussed. The characteristics discussed include directional stability, overturning tendencies, steering and ground handling, shimmy, takeoff, and porpoising. The conclusions are summarized in a table.
Date: April 1937
Creator: Wenzinger, Carl J. & Kantrowitz, A. R.
System: The UNT Digital Library
Notes on New French Commercial Airplanes (open access)

Notes on New French Commercial Airplanes

This document discusses the types of commercial planes ordered by Air France. Characteristics of the Wibault 670, the Dewoitine D.620, Bloch 300, and the Potez 620 airplanes are included. Pictures and diagrams of these aircraft are also included.
Date: April 4, 1935
Creator: unknown
System: The UNT Digital Library
The Effect of Lateral Inclination of the Thrust Axis and of Sweepback of the Leading Edge of the Wing on Propulsive and Net Efficiencies of a Wing-Nacelle-Propeller Combination (open access)

The Effect of Lateral Inclination of the Thrust Axis and of Sweepback of the Leading Edge of the Wing on Propulsive and Net Efficiencies of a Wing-Nacelle-Propeller Combination

"This report describes and gives the results of tests made to determine the effect of lateral inclination of the propeller thrust axis to the direction of flight. A wing-nacelle-propeller combination with the nacelle axis located successively parallel to and at 15 degrees to the perpendicular to the leading edge of a wing was tested with the combination at several angles of yaw. Tests of the wing alone at the same angles of yaw were also made" (p. 1).
Date: April 1935
Creator: Wood, Donald H. & Windler, Ray
System: The UNT Digital Library
Large-Scale Boundary-Layer Control Tests on Two Wings in the NACA 20-Foot Wind Tunnel, Special Report (open access)

Large-Scale Boundary-Layer Control Tests on Two Wings in the NACA 20-Foot Wind Tunnel, Special Report

Report discussing tests performed on two different wings to determine the increase in lift obtainable by removing the boundary layer and power required for the blower. The results for the stub wing were more favorable than the large-span wing.
Date: April 1935
Creator: Freeman, Hugh B.
System: The UNT Digital Library
Resume of Present Data on Load Distribution on Slots and Flaps, Special Report (open access)

Resume of Present Data on Load Distribution on Slots and Flaps, Special Report

This report covers a study of the generally available data on load distribution on slots and flaps. The study was made by the National Advisory Committee for Aeronautics at the request of the Material Division, Army Air Corps to furnish information applicable to design criteria for slots and flaps of various types. The data are presented in three main sections: slots (Handley page type), auxiliary airfoils (fixed), and flaps.
Date: April 1934
Creator: Wenzinger, Carl J.
System: The UNT Digital Library