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Reserves, Bed Characteristics, and Coking Properties of the Willow Creek Coal Bed, Kemmerer District, Lincoln County, Wyoming

Description: Report issued by the Bureau of Mines discussing the coal reserves and coking properties of the Willow Creek bed in Lincoln County, Wyoming. Analyses of the coal bed are presented in detail. This report includes tables, illustrations, photographs, and a map.
Date: 1945
Creator: Toenges, Albert L.; Davis, J. D.; Turnbull, Louis A. & Schopf, J. M.
Partner: UNT Libraries Government Documents Department

Study of the Alaska Tundra with Reference to its Reactions to Reindeer and other Grazing

Description: The Alaska tundra varies in width from a few miles to 200 miles along the Bering Sea and from 100 to 150 miles along the Arctic coast. Plant composition is largely lichens, grasses, sedges, alpines, and shrubs, of which 16 distinct vegetative types are described in this report.
Date: 1945
Creator: Palmer, L. J.
Partner: UNT Libraries Government Documents Department

Summary of Airfoil Data

Description: The historical development of NACA airfoils is briefly reviewed. New data are presented that permit the rapid calculation of the approximate pressure distributions for the older NACA four-digit and five-digit airfoils by the same methods used for the NACA 6-series airfoils. The general methods used to derive the basic thickness forms for NACA 6 and 7-series airfoils together with their corresponding pressure distributions are presented. Detail data necessary for the application of the airfoils to wing design are presented in supplementary figures placed at the end of the paper. The report includes an analysis of the lift, drag, pitching-moment, and critical-speed characteristics of the airfoils, together with a discussion of the effects of surface conditions. Available data on high-lift devices are presented. Problems associated with lateral-control devices, leading-edge air intakes, and interference are briefly discussed, together with aerodynamic problems of application. (author).
Date: January 1, 1945
Creator: Abbott, Ira H; Von Doenhoff, Albert E & Stivers, Louis, Jr
Partner: UNT Libraries Government Documents Department

Summary of measurements in Langley full-scale tunnel of maximum lift coefficients and stalling characteristics of airplanes

Description: The results of measurements in the Langley full-scale tunnel of the maximum lift coefficients and stalling characteristics of airplanes have been collected. The data have been analyzed to show the nature of the effects on maximum lift and stall of wing geometry, fuselages and nacelles, propeller slipstream, surface roughness, and wing leading-edge appendages such as ducts, armaments, tip slats, and airspeed heads. Comparisons of full-scale-tunnel and flight measurements of maximum lift and stall are included in some cases, and the effects of the different testing techniques on the maximum-lift measurements are also given.
Date: January 1, 1945
Creator: Sweberg, Harold H & Dingeldein, Richard C
Partner: UNT Libraries Government Documents Department

A systematic investigation of pressure distributions at high speeds over five representative NACA low-drag and conventional airfoil sections

Description: Pressure distributions determined from high-speed wind-tunnel tests are presented for five NACA airfoil sections representative of both low-drag and conventional types. Section characteristics of lift, drag, and quarter-chord pitching moment are presented along with the measured pressure distributions for the NACA 65sub2-215 (a=0.5), 66sub2-215 (a=0.6), 0015, 23015, and 4415 airfoils for Mach numbers up to approximately 0.85. A critical study is made of the airfoil pressure distributions in an attempt to formulate a set of general criteria for defining the character of high speed flows over typical airfoil shapes. Comparisons are made of the relative characteristics of the low-drag and conventional airfoils investigated insofar as they would influence the high-speed performance and the high-speed stability and control characteristics of airplanes employing these wing sections.
Date: January 1, 1945
Creator: Graham, Donald J; Nitzberg, Gerald E & Olson, Robert N
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Tests of a 1/5-Scale Semispan Model of the Republic XF-12 Horizontal Tail Surface

Description: Wind-tunnel tests of a 1/5-scale semispan model of the Republic XF-12 horizontal tail surface equipped with an internally balanced elevator were conducted in the 6- by 6-foot test section of the Langley stability tunnel. The tests included measurements of the aerodynamic characteristics of the horizontal tail with and without a beveled trailing edge and also included measurements of the tab characteristics. The variation of the aerodynamic characteristics with boundary-layer conditions and leakage in the internal-balance chambers, measurements of the boundary-layer displacement thickness near the elevator hinge axis, and pressure distributions at the mean geometric chord were also obtained. The results showed that the hinge-moment characteristics of the elevator were critical to boundary-layer conditions and internal-balance leakage. Increasing the boundary-layer displacement thickness by use of roughness strips reduced the rate of change of elevator hinge moments with tab deflection by about 20 percent. The present horizontal tail appears to be unsatisfactory for longitudinal stability with power on, however, an increase in horizontal-tail lift effectiveness should correct this difficulty. The maneuvering stick force per unit acceleration will be extremely critical to minor variations of the elevator hinge moments if the elevator is linked directly to the stick.
Date: January 1, 1945
Creator: Denaci, H. G.
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Tests of a 1/6-Scale Model of Republic XF-12 Vertical Tail Incorporating a De-Icing Air Duct

Description: A 1/6-scale model of the Republic XF-12 vertical tail with stub fuselage, stub horizontal tail, and a de-icing air duct was tested in the Langley stability tunnel. The investigation consisted of a study of the effects of the duct, with and without air flow, on the aerodynamic characteristics of the model. The model tested was a revision of a model previously tested in the Langley stability tunnel. The revised model differed from the original model in that it incorporated a de-icing air duct, included a dorsal fin, and had a larger stub fuselage. A comparison of data obtained form tests of the original and revised models was made. The results of the investigation indicated that the air duct had very little effect on the aerodynamic characteristics of the model. A small change occurred in the variation of rudder hinge-moment coefficient with angle of attack but it is believed that this change can be corrected by a properly applied spring tab.
Date: January 1, 1945
Creator: MacLachlan, Robert & Miller, Sadie M.
Partner: UNT Libraries Government Documents Department

Wind Tunnel Investigation of the Effects of Slot Shape and Flap Location on the Characteristics of a Low-Drag Airfoil Equipped with a 0.25-Chord Slotted Flap

Description: Tests were conducted at dynamic pressure of 50 lb per square foot with lift drag and pitch moment measurements throughout useful angle of attack range for constant flap deflection and position of a low-drag airfoil. Two slots were investigated and practical flap paths were selected for each Slot shape had a negligible effect on the maximum lift coefficient flap deflected, the rounded-entry slot had lower profile drag.
Date: December 28, 1944
Creator: Weisman, Yale & Holtzclaw, Ralph W.
Partner: UNT Libraries Government Documents Department