An Analysis of the Effects of Aeroelasticity on Static Longitudinal Stability and Control of a Swept-Wing Airplane (open access)

An Analysis of the Effects of Aeroelasticity on Static Longitudinal Stability and Control of a Swept-Wing Airplane

From Introduction: "The results of the aforementioned study are presented in this report together with the method of analysis employed. The net stability change is shown together with the individual contributions due to flexibility of wing, tail, and fuselage, both including and neglecting the effect of inertial loads."
Date: March 19, 1951
Creator: Skoog, Richard B.
System: The UNT Digital Library
Investigation of wear and friction properties under sliding conditions of some materials suitable for cages of rolling-contact bearings (open access)

Investigation of wear and friction properties under sliding conditions of some materials suitable for cages of rolling-contact bearings

"An investigation of wear and friction properties of a number of materials sliding against SAE 52100 steel was conducted. These materials included brass, bronze, beryllium copper, monel, nichrome v, 24S-T aluminum, nodular iron, and gray cast iron. The metals investigated may be useful as possible cage (separator or retainer) materials for rolling-contact bearings of high-speed turbine engines. The ability of materials to form surface films that prevent welding is a most important factor in both dry friction and boundary lubrication" (p. 117).
Date: March 26, 1951
Creator: Johnson, Robert L.; Swikert, Max A. & Bisson, Edmond E.
System: The UNT Digital Library
Flight investigation of the effect of control centering springs on the apparent spiral stability of a personal-owner airplane (open access)

Flight investigation of the effect of control centering springs on the apparent spiral stability of a personal-owner airplane

Report presents the results of a flight investigation conducted on a typical high-wing personal-owner airplane to determine the effect of control centering springs on apparent spiral stability. Apparent spiral stability is the term used to describe the spiraling tendencies of an airplane in uncontrolled flight as affected both by the true spiral stability of the perfectly trimmed airplane and by out-of-trim control settings. Centering springs were used in both the aileron and rudder control systems to provide both a positive centering action and a means of trimming the airplane.
Date: March 22, 1951
Creator: Campbell, John P.; Hunter, Paul A.; Hewes, Donald E. & Whitten, James B.
System: The UNT Digital Library
Sound from a two-blade propeller at supersonic tip speeds (open access)

Sound from a two-blade propeller at supersonic tip speeds

Report presents the results of sound measurements at static conditions made for a two-blade 47-inch-diameter propeller in the tip Mach number range 0.75 to 1.30. For comparison, spectrums have been obtained at both subsonic and supersonic tip speeds. In addition, the measured data are compared with calculations by the theory of Gutin which has previously been found adequate for predicting the sound at subsonic tip speeds. Curves are presented from which the maximum over-all noise levels in free space may be estimated if the power, tip Mach number, and distance are known.
Date: March 29, 1951
Creator: Hubbard, Harvey H. & Lassiter, Leslie W.
System: The UNT Digital Library
Experimental and theoretical studies of area suction for the control of the laminar boundary layer on an NACA 64A010 airfoil (open access)

Experimental and theoretical studies of area suction for the control of the laminar boundary layer on an NACA 64A010 airfoil

From Summary: "A low-turbulence wind-tunnel investigation was made of an NACA 64A010 airfoil having a porous surface to determine the reduction in section total-drag coefficient that might be obtained at large Reynolds numbers by the use of suction to produce continuous inflow through the surface of the airfoil (area suction). In addition to the experimental investigation, a related theoretical analysis was made to provide a basis of comparison for the test results."
Date: March 30, 1951
Creator: Braslow, Albert L.; Burrows, Dale L.; Tetervin, Neal & Visconti, Fioravante
System: The UNT Digital Library