UNT Libraries Government Documents Department - 22 Matching Results

Search Results

Analysis of wind-tunnel stability and control tests in terms of flying qualities in full-scale airplanes

Description: From Summary: "The analysis of results of wind-tunnel stability and control tests of powered airplane models in terms of the flying qualities of full-scale airplanes is advocated. In order to indicate the topics upon which comments are considered desirable in the report of a wind-tunnel stability and control investigation and to demonstrate the nature of the suggested analysis, the present NACA flying-qualities requirements are discussed in relation to wind-tunnel tests. General procedures for the estimation of flying qualities from wind-tunnel tests are outlined."
Date: October 1943
Creator: Kayten, Gerald G.

Critical stresses for plates

Description: Report presenting the basic methods of theoretically calculating the critical stress for plates with elastically restrained edges. Design charts for various types of sections and columns and critical stress for flat plates and curved sheets are provided.
Date: October 1943
Creator: Lundquist, Eugene E. & Schuette, Evan H.

Effect of pH on strength of resin bonds

Description: Report presenting an investigation to determine the effect of acid on the strength and aging properties of various types of resin bonds for plywood. The pH values of the birch plywoods, flexural and impact strengths before and after aging of birch plywoods bonded with urea-formaldehyde resins and phenolic resins, and delamination properties of birch plywoods bonded with each type of resin are provided.
Date: October 1943
Creator: Rinker, R. C.; Reinhart, F. W. & Kline, G. M.

Flying qualities of a twin-engine patrol airplane as estimated from wind-tunnel tests

Description: Report presenting an estimate of the flying qualities of a twin-engine patrol airplane from wind-tunnel test results in comparison with flight observations as a possible guide in determining changes which would be necessary to improve these qualities. Results regarding the longitudinal and lateral stability and control of this airplane are provided.
Date: October 1943
Creator: Stevens, Victor I., Jr.

Heat Transfer Over the Circumference of a Heated Cylinder in Transverse Flow

Description: A method for recording the local heat-transfer coefficients on bodies in flow was developed. The cylinder surface was kept at constant temperature by the condensation of vapor except for a narrow strip which is heated separately to the same temperature by electricity. The heat-transfer coefficient at each point was determined from the electric heat output and the temperature increase. The distribution of the heat transfer along the circumference of cylinders was recorded over a range of Reynolds numbers of from 5000 to 426,000. The pressure distribution was measured at the same time. At Reynolds numbers up to around 100,000 high maximums of the heat transfer occurred in the forward stagnation point at and on the rear side at 180C, while at around 80 the heat-transfer coefficient on both sides of the cylinder behind the forward stagnation point manifested distinct minimums. Two other maximums occurred at around 115 C behind the forward stagnation point between 170,000 and 426,000. At 426,000 the heat transfer at the location of those maximums was almost twice as great as in the forward stagnation point, and the rear half of the cylinder diffused about 60 percent of the entire heat, The tests are compared with the results of other experimental and theoretical investigations.
Date: October 1, 1943
Creator: Schmidt, Ernst & Wenner, Karl

Investigation of surface irregularities on an NACA 63(420)-416, a=1.0 airfoil section for the Glenn L. Martin Company design 195

Description: Report presenting the results of an investigation made in the two-dimensional low-turbulence pressure tunnel of surface irregularities on a low-drag airfoil section. The primary objective was to determine the effects of riveted and piano-hinge-type skin joints and of an aileron slot of the drag characteristics. Any type of surface irregularities at the front spar were found to cause substantial increase in drag.
Date: October 1943
Creator: Braslow, Albert L.

The Measurement of Fuel-Air Ratio by Analysis of the Oxidized Exhaust Gas

Description: An investigation was made to determine a method of measuring fuel-air ratio that could be used for test purposes in flight and for checking conventional equipment in the laboratory. Two single-cylinder test engines equipped with typical commercial engine cylinders were used. The fuel-air ratio of the mixture delivered to the engines was determined by direct measurement of the quantity of air and of fuel supplied and also by analysis of the oxidized exhaust gas and of the normal exhaust gas. Five fuels were used: gasoline that complied with Army-Navy Fuel Specification, No. AN-VV-F-781 and four mixtures of this gasoline with toluene, benzene, and xylene. The method of determining the fuel-air ratio described in this report involves the measurement of the carbon-dioxide content of the oxidized exhaust gas and the use of graphs or the presented equation. This method is considered useful in aircraft, in the field, or in the laboratory for a range of fuel-air ratios from 0.047 to 0.124.
Date: October 1, 1943
Creator: Memm, J. Lawrence, Jr.

National Safety Competition of 1942

Description: Report issued by the U.S. Bureau of Mines on its annual safety contest between mine workers. Different types of mines enrolled in the competition and the winners and honorable mentions for 1942 are presented. This report includes tables.
Date: October 1943
Creator: Adams, William Waugh & Lawrence, T. D.

Report on Reserves and Production Situation of Vanadiferous and Related Ores in Colorado Plateau Region

Description: From introduction: The general distribution of known deposits of vanadium-bearing sandstone, which also contain some uranium and radium, is shown in figure 1 1/ and Exhibit A, plate 53. 2/ During 1939-41 the Geological Survey made detailed geological studies of these deposits in the Uravan district, Montrose County, Colorado, as well as preliminary examinations in other parts of the Colorado Plateau vanadium region. In 1942 detailed geological studies were made o the deposits in the Egnar-Slick Rock district, San Miguel Co., Colo.; 3/ the Carrizo Moungains district, Navajo Indian Reservation, Arizona and New Mexico; 4/ the Placerville district, San Miguel County, Colo. 5/ and the Monticello district, San Juan Co., Utah. 6/ Since May 3, 1943, the Gelogical Survey has guided the Bureau of Mines program of prospecting these deposits in parts of Colorado and Utah.
Date: October 10, 1943
Creator: Fischer, Richard P. & Stokes, William Lee

Stresses around rectangular cut-outs in skin-stringer panels under axial loads 2

Description: From Summary: "Cut-outs in wings or fuselages produce stress concentrations that present a serious problem to the stress analyst. As a partial solution of the general problem, this paper presents formulas for calculating the stress distribution around rectangular cut-outs in axially loaded panels. The formulas are derived by means of the substitute-stringer method of shear-lag analysis."
Date: October 1943
Creator: Kuhn, Paul; Duberg, John E. & Diskin, Simon H.

Use of stagnation temperature in calculating rate of heat transfer in aircraft heat exchangers

Description: From Summary: "Theoretical and experimental investigations of the effect of frictional heat on the rate of heat transmission at high fluid velocities are briefly reviewed. On the basis of these investigations, calculations are made which show that the use of the stagnation temperature of the cooling air as the effective temperature for heat transfer in an aircraft heat exchanger is sufficiently accurate."
Date: October 1943
Creator: Wood, George P.