Metal-Truss Wing Spars (open access)

Metal-Truss Wing Spars

The purpose of the study was to develop improvements in the current methods for the calculation of the loads in members of metal truss wing spars which are subjected to combined bending and compression. The theory developed here has two important practical applications. One is the calculation of the effective moment of inertia of a truss spar from the geometry of the spar and the loads to which the spar is to be subjected. The second is the determination of the most economical location of metal for stiffening a truss spar which has too much deflection.
Date: July 1931
Creator: Swickard, Andrew E.
System: The UNT Digital Library
The Effect of Injection-Valve Opening Pressure on Spray-Tip Penetration (open access)

The Effect of Injection-Valve Opening Pressure on Spray-Tip Penetration

"The effect of various injection-valve opening pressures on the spray-tip penetration was determined for several injection pressure. A common-rail fuel injection system was used. For a given injection pressure a maximum rate of penetration was obtained with an injection-valve opening pressure equal to the injection pressure" (p. 1).
Date: July 1931
Creator: Rothrock, A. M. & Marsh, E. T.
System: The UNT Digital Library
Tests of Six Symmetrical Airfoils in the Variable Density Wind Tunnel (open access)

Tests of Six Symmetrical Airfoils in the Variable Density Wind Tunnel

"This paper is the first of a series covering an investigation of a family of airfoils all formed from a basic profile. It gives in preliminary form the results of six symmetrical airfoils, differing only in maximum thickness. The maximum thickness-to-chord ratios are 0.06, 0.09, 0.12, 0.15, 0.18, and 0.21" (p. 1).
Date: July 1931
Creator: Jacobs, Eastman N.
System: The UNT Digital Library