Report presenting an experimental investigation concerned primarily with the extension of test data on the drag of revolving disks, cylinders, and streamline rods to high Mach numbers and Reynolds numbers. The tests generally confirm earlier theories and add in some new results. One of the primary findings of interest is that skin friction does not depend on Mach number.

Investigations were undertaken to improve the ailerons of a P-51 fighter so as to obtain greater effectiveness without increasing the stick forces. Modifications consisted of increasing the deflection range of the aileron to 70 percent and changing the original concave section to a thick section with beveled trailing edge. Results of the modified ailerons showed an increase in effectiveness over the original aileron of 70 percent at low speed and 55 percent at high speeds.

Report presenting flight measurements made on a modern pursuit airplane to determine the approximate magnitude of the horizontal tail loads in accelerated flight. Pressures at a few points were used as an index of the tail loads by correlating these pressures with complete pressure-distribution data obtained in the NACA full-scale tunnel.

From Summary: "A general representation of fan and turbine arrangements on a single classification chart is presented which is made possible by a particular definition of the stage of an axial-flow fan or turbine. Several unconventional fan and turbine arrangements are indicated and the applications of these arrangements are discussed."

Report details the development of design equations for double-panel, air-heated windshields with ice prevention properties. The application of the equations and suggestions for experimental flight testing are described.

The methods of NACA TN No. 995 have been slightly modified and extended in include flows with circulation by considering the alteration of the singularities of the incompressible solution due to the presence of the hypergeometric functions in the analytic continuation of the solution. It was found that for finite Mach numbers the only case in which the nature of the singularity can remain unchanged is for a ratio of specific heats equal to -1. From a study of two particular flows it seems that the effect of geometry cannot be neglected, and the conventional "pressure-correction" formulas are not valid, even in the subsonic region if the body is thick, especially if there is a supersonic region in the flow.

Report presenting a series of wind-tunnel tests made in the 7- by 10-foot tunnel of the Curtiss XBTC-2 model with power. The object of the tests was to determine and to improve, as necessary, the complete aerodynamic characteristics of the model. The report includes the results of the longitudinal stability investigation of the original model along with results from tests of various modifications.

Note presenting computations made to determine the effects of some airplane design trends on the fin area and the dihedral angle required for lateral stability. The specific factors studied were wing loading, moments of inertia in roll and yaw, wing chord, and tail length. The results of the computations are presented in the form of diagrams of variations of fin area with dihedral angle for neutral stability.

Report issued by the Bureau of Mines over studies of the processes used in oil-shale assay methods. Updated methods are provided from a previous report on the same topic. This report includes tables, graphs, and illustrations.

Report issued by the Bureau of Mines over petroleum-engineering studies conducted at the Atlanta oil field. The methods used for the study are presented and discussed. This report includes tables, maps, illustrations, and photographs.

Report issued by the Bureau of Mines over studies conducted on vanadium deposits in Lincoln County. As noted in the introduction, "the following report covers the history of the district, outlines the physical features and communications, mentions the property, and notes the ownership. The deposits and ore are described, and work performed by the Bureau of Mines is explained in detail" (p. 1). This report includes tables, and maps.

Report issued by the Bureau of Mines on exploration by diamond drilling in Pend Oreille County. Results of the exploration are presented. This report includes tables, maps, illustrations, and photographs.

Report issued by the U.S. Bureau of Mines on the magnetometer surveys conducted on the coastal region of Oregon. The methods, geology, and locations surveyed are presented. This report includes maps, graphs, and illustrations.

Report issued by the U.S. Bureau of Mines regarding specific manganese ore from Nevada and its use in electrolytic production. The development processes and methods are presented. This report includes tables, maps, illustrations, and photographs.

Report issued by the U.S. Bureau of Mines on the use of oil field brine in secondary recovery methods. Characteristics of the brine, and methods used in recovery processes are presented. This report includes tables, graphs, maps, and illustrations.

Report issued by the U.S. Bureau of Mines on the differing conditions of oxygen in explosives. Results from explosives samples with oxygen variations are presented. This report includes tables.

Report from the U.S. Bureau of Mines over the studies conducted on the Daisy mine and the Hillside mine in Hardin County, Illinois. Properties of the mines, and the types of mineral deposits found in each are presented. This report includes maps, and illustrations.

Report issued by the U.S. Bureau of Mines on the sampling of chrome ore deposits in the western United States. Physical properties of the samples collected are presented. This report includes tables.

Report issued by the Bureau of Mines over the manganese deposits in Sierra County, New Mexico. Descriptions of the physicality, and characteristics of the manganese ore are presented. This report includes tables, maps, and illustrations.

Report issued by the Bureau of Mines over briquetting of coal for development of more effective fuel. Materials, equipment, and processes are discussed. This report includes tables, illustrations, and photographs.

Abstract: "The sensitivity to fast neutrons of a CP Meter ionization chamber of the type used for health physics beta and gamma survey measurements has been investigated."

Introduction: "This report covers progress on the testing of the General Engineering and Consulting Laboratories Turbine Pump No. 1 from May 1, 1948 to Jun 15, 1948. All testing prior to April 30, 1948 has been described in Redox Experiment Testing Report No. 1 (Document HW-9474) and No. 2 (Document HW-9694)."

The following report studies an estimation of the amount of Pu(III) and Pu(IV) present in the IBP Stream, with the purpose of establishing an analytical, method suitable for routine control analysis. A method is discussed that is based on carrying Pu(IV) upon a zirconium phanylarsonate precipitate.

Abstract: "A method has been established for the estimation of volatile organic acids in aqueous process solutions containing UNH, nitric acid, ANN, sodium dichromate and small amounts of hexone. The practice is to distill a 400 ul or 500 ul sample in the presence of an excess of phosphoric acid and ferrous sulfate under a high vacuum; a special apparatus utilizing a receiver cooled with a dry ice-isopropanol mixture is employed. The distillate is taken up in isopropanol and then titrated potentiometrically with standard potassium hydroxide solution. Since nitric acid and organic acids are present, two end points are observed. The potassium hydroxide added between these end points is equivalent to the organic acids. In the titration, CO2 from the atmosphere or in the potassium hydroxide is a source of error. The former was avoided and correction was made for the latter."