From Summary: "The present report is, in the first place, a compilation of the test results now available from wing tests up to angles of attack 90^o. Reports are also given of tests with monoplane and auxiliary wings in the Gottingen wind tunnel for the purpose of plotting a steadily rising curve of the normal force as a foundation of the angle of attack."

These calculations were based on the shape of the ZR III, with the following simplifications: cars, fins, and rudders removed; all cross sections replaced by equivalent circular cross sections. Under these assumptions the pressure distribution was calculated for the following cases: symmetrical case, or flow parallel to the axis; unsymmetrical case, or flow at an angle to the axis. In both cases the simple potential flow first forms the basis for the determination of the pressure distribution.

Circular presenting a description of the Caproni 90 P.B., which is the largest airplane in existence at the time of the report. Details of the weight, construction, wings, controls, fuselage, tail, landing gear, flying qualities, and photographs are provided.

Circular presenting a description of the Comte A.C. 3, which is a high-wing monoplane with tow tandem 600 hp Hispano-Suiza engines mounted above the fuselage. Details of the design, fuel tanks, fuselage, pilot seating, engine, wings, safety factors, and flight qualities are provided.

Describes the steps taken to build and set traps for coyotes and wolves in the United States.

The present report gives the results of tests which were made for the purpose of solving the problem of whether diagrams obtained from pressure tests could be conclusive for the determination of the safe impact coefficients. It is first established that the rubber rings adhere firmly to the compression surfaces during deformation. Suggestions are thus obtained for a constructive simplification of the rubber rings. The hysteresis phenomenon is ascribed to external and internal friction forces. A device for falling tests is then described with which the process of shock absorption with rubber rings was tested.

Memorandum presenting an investigation to determine the variations in the velocity of the air when it was obliged to flow about a wing profile. Special interest was paid to the determination of velocity as compared with that of the undisturbed flow and of the velocity drop in successive planes perpendicular to the flow direction at increasing distances from the wing profile.

This report is concerned with the derivation of a chart for estimating the absolute ceiling of an airplane. This chart may be used in conjunction with the usual curves of power required and power available as an accurate substitute for extended calculation, or it may be used in the estimation of absolute ceiling when power curves are not available.

A review of various methods to prevent ice formation and adhesion to aircraft surfaces is given. It was concluded that the adhesion of ice to a surface may be reduced somewhat by the application of certain waxes and varnishes. In the experiments described, the varnishes containing calcium stearate and calcium oleate gave the best results. In wind tunnel tests, the adhesion was further reduced by the application of these waxes and varnishes to a thin, heat insulating layer of rubber.

Recipes for dishes made with rabbit meat.

The results presented in this note show the effect of twist and sweepback on the span load distribution over two monoplane wing models. The tests were made in the Atmospheric Wind Tunnel of the Langley Memorial Aeronautical Laboratory. The data are taken from the results of an investigation dealing primarily with lateral stability. As presented, they are suitable as an aid in the structural design of certain monoplane wings.

This report will present ideas closely related to the vortex conception and illustrate them in the simplest possible terms. In addition to these general considerations, this report will attempt to show the application of the vortex theory in connection with the wing theory.

This report presents an investigation of the design and construction of various types of landing gears. Some of the items discussed include: chassises, wheels, shock absorbers (rubber disk and rubber cord), as well as oleopneumatic shock absorbers. Various types of landing gears are also discussed such as the Messier, Bendix, Vickers, and Bleriot.

Circular presenting a description of the Bernard 80 aircraft. Details are provided on the body shape, wings, ribs, fuel requirements, and flight characteristics.

Describes steps for creating a brace system for farm buildings in order to prevent distortion and collapse.

Report issued by the U.S. Bureau of Mines on the coal mine related deaths that occurred during the month of June, 1931. The number of fatalities and the causes of each are presented. This report includes tables and a graph.

This report deals first with the fundamental data required for the investigation. These are chiefly the aerodynamic forces and moments acting on an airplane in a flat spin. It is shown that these forces and moments depend principally on the angle of attack and on the rotation about the path axis, and can therefore either be measured in a wind tunnel or calculated from wind-tunnel measurements of lift, drag and moment about the leading edge of the wing of an airplane model at rest.

"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).

The following discussion is at first restricted to the light-oil engines now in use. We shall consider how far it is possible to reduce fire hazards by changes in the design of the engines and carburetors and in the arrangement of the fuel pipes.

Report issued by the U.S. Bureau of Mines on the leaching of copper ores. The different strengths and cycles of solvents to extract impurities from the ore are presented. This report includes tables and graphs.

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.

Circular presenting a description of the Mono-Spar light airplane, which is a small twin-engined low-wing cabin monoplane. A description of the design, structural features, characteristics, flying qualities, photographs, and drawings are provided.

Volume provides a summary of the progress of each agricultural experiment station. Also includes statistics, a bibliography of experiment station publications, and selected studies.

Describes varieties of cotton fabrics and provides suggestions for their use in clothing and other sewn products. Provides suggestions for evaluating the quality of cotton fabrics.