This report is a description of a method of propelling airplanes by the reaction of jet propulsion. Air is compressed and mixed with fuel in a combustion chamber, where the mixture burns at constant pressure. The combustion products issue through a nozzle, and the reaction of that of the motor-driven air screw. The computations are outlined and the results given by tables and curves.

"In connection with the study of aircraft and propeller noises, the National Advisory Committee for Aeronautics has developed an instrument for sound-frequency analysis which differs fundamentally from previous types, and which, owing to its simplicity of principle, construction, and operation, has proved to be of value in this investigation. The method is based on the well-known fact that the Ohmic loss in an electrical resistance is equal to the sum of the losses of the harmonic components of a complex wave, except for the case in which any two components approach or attain vectorial identity, in which case the Ohmic loss is increased by a definite amount" (p. 605).

This report presents the results of an investigation of the corrosion of aluminum alloy sheet materials used in aircraft. It has for its purpose to study the causes of corrosion embrittlement in duralumin-type alloys and the development of methods for its elimination. The report contains results, obtained in an extensive series of weather-exposure tests, which reveal the extent to which the resistance of the materials to corrosion was affected by variable factors in their heat treatment and by the application of various surface protective coatings.

Annual report submitted by the Boy Scouts of America to Congress describing highlights from 1940, activities, organizational leadership, and other information about scouting programs.

Abstract. a method of recovering thorium from slag from the bomb process of producing thorium has been developed. HCl and NaOH are the only chemicals required in quantity. Materials required for a representative slag are given.

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Welding is used to fabricate titanium and titanium-alloy components for air-frames, Jet engines, missiles, and chemical equipment. Annong the most important considerations in adapting titanium and its alloys to welded components is to use proper welding procedures and to select alloys that have the required weld-joint properties. The chemical and metallurgical characteristics that affect the selection of welding processes and alloys are discussed. Also, information is presented on surface preparation, welding procedures, and quality control. In addition, detailed data on the mechanical properties of welded joints in the commercial grades of titanium and titanium alloys and how these properties are affected by heat treatment and elevated temperatures are presented. (auth)

From Summary: "Flight tests have been made to determine the longitudinal stability and control and stalling characteristics of a North American P-51H airplane. The results indicate that the airplane has satisfactory longitudinal stability in all the flight conditions tested at normal loadings up to 25,000 feet altitude. At Mach numbers above 0.7, the elevator push force required for longitudinal trim decreased somewhat because of compressibility effects."

"An extended analysis was made of the previously reported performance investigation of the original compressor from the XJ-41-V turbojet engine and a similar compressor revised a to obtain a 33-percent increase in the geometric passage area at the vaned-collector entrance. This analysis was based on the concept of the vaned-collector entrance as the throat section of a nozzle. Because of nonuniform air distribution at the vaned-collector entrance, approximately 90 percent of the available flow area was utilized in the original compressor and 94 percent in the revised compressor" (p. 1).

The cloud chamber is a means of observing the path of ionizing radiation. It does not reveal the radiation directly, but gives a visible trail of the path along which the radiation has traveled. The trail is formed by vapor condensing upon pairs of ions remaining after an ionizing particle has passed through the medium. The mutual interaction among rays, atoms, nuclei, and particles, can be studied and measured with the aid of vapor trails. Measurements of changes in direction and range as recorded on the photographs may be interpreted in terms of changes in momentum and energy of the particles in these reactions. To obtain a precision measurement is difficult with a cloud chamber. The dependence of the apparatus upon a sudden gas expansion is certain to create distortions resulting from turbulence. Furthermore, since any radiation is subject to variations, precision measurements can be obtained only be the collection of numerous observations for statistical analysis. This document details the design, operation, and limitations of cloud chambers.

Memorandum presenting an investigation of the effects of stator cone angle and tip leakage on turbine performance. A single-stage turbine with 40-percent reaction was operated with two stators and two stationary shrouds. The turbine was operated at an entrance temperature of 660 degrees R with total-pressure ratios from 1.25 to 3.70 and equivalent mean blade speeds from 166 to 655 feet per second.

A first approximation of the gas required to cool control rods for Pile Area G is presented in the following report. Since the results are based on a number of assumptions and approximations, they should be considered only as a first approximation and subject to revision. A gadolinium-stainless steel control rod can probably be readily cooled by gas. A boron-stainless steel control rod would be difficult to cool with gas and would probably require about 1,000 lbs./hr. of helium per rod. Carbon dioxide has a slight advantage over helium as a cooling agent for control rods. This advantage is so small that the problems of gas cooling control rods should not influence the decision whether to use helium or carbon dioxide in the pile.

This report studies tritium oxides and tritium in water vapor, a product of P-10.

Though the product of P-10 is T{sub 2}, the chief hazard is the tritium oxides, and tritium in water vapor might exchange with the hdyrogen in the water. If a catalyst is present, essentially all of the tritium would be exchanged. Because we do not know what catalyzers may exist at P-10 or in the lungs of a person breathing tritium, a ready answer cannot be given to the question of the importance of the exchange reactions. The HT + H{sub 2}O {r_reversible} HTO + H{sub 2} is also considered. The same conclusion holds, most of the tritium will be exchanged; however the equilibrium constant is needed. 1 fig.

The design of the present time of light mass spectrograph is similar to that of the isotron devised some time ago for isotope separation. The spectrograph will employ the time of flight principle only for the isotopic analysis of small samples.

Report presenting an investigation of zero-lift drag of a fin-stabilized wing-body combination from high-subsonic to supersonic speeds in a range of Reynolds numbers. The wing was unswept about the 74.5-percent-chord line, an aspect ratio of 3.04, a taper ratio of 0.394, and 4.5-percent-thick modified hexagonal airfoil sections. Results regarding total drag, wing-plus-interference drag, and base pressure are provided.

Annual report submitted by the Boy Scouts of America to Congress describing highlights from 1952, activities, finance, public relations, programming, organizational leadership, and other information about scouting programs.

Abstract: "A description of the demand computer and its functions is given. Methods of testing and adjusting, and gain and response curves for the system and its parts are included."

Force and pressure-recovery characteristics of a nacelle-type conical-spike inlet with a fixed-area bypass located in the top or bottom of the diffuser are presented for flight Mach numbers of 1.6, 1.8, and 2.0 for angles of attack from 0 degrees to 9 degrees. Top or bottom location of the bypass did not have significant effects on diffuser pressure-recovery, bypass mass-flow ratio, or drag coefficient over the range of angles of attack, flight Mach numbers, and stable engine mass-flow ratios investigated. A larger stable subcritical operating range was obtained with the bypass on the bottom at angles of attack from 3 degrees to 9 degrees at a flight Mach number of 2.0. At a flight Mach number of 2.0, the discharge of 14 percent of the critical mass flow of the inlet by means of a bypass increased the drag only one-fifth of the additive drag that would result for equivalent spillage behind an inlet normal shock without significant reductions in diffuser pressure recovery.

"The influence of triangular-shaped end plates on the lift and the flow field of a canard-type control surface mounted on a symmetrical fuselage was investigated in the Lewis 8- by 6-foot supersonic wind tunnel at a Mach number of 2.00, body angle of attack of 2 degrees, and control-surface deflection angles of 3 degrees, 6 degrees, 8 degrees, and 10 degrees. The investigation demonstrated that the addition of end plates to a canard-type control surface increased its lift and rearranged the single vortex into a two-vortex system. Perforating the end plates reduced these effects and resulted in a decrease in lift and a change in the flow-field characteristics" (p. 1).

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The following report analyzes results from studies made while applying chelating agents to ion exchange separations of the elements americium and curium.

This is a progress report of the production reactors on the Hanford Reservation for the month of February 1951. This report takes each division (e.g., manufacturing, medical, accounting, occupational safety, security, reactor operations, etc.) of the site and summarizes its accomplishments and employee relations for that month.

The following modifications are planned to facilitate greater usefulness of available target space in the west tangent tank: (1) A 3/32-inch x 6-inch x 106-inch aluminum window is to be added to the outer radius tank wall. (2) One 12-inch x 6-inch air lock is to be added on the inside centerline of the reentrant section on the west tangent tank. (3) Two 24-inch x 30-inch openings are to be cut on the beam centerline in the top of the west tangent tank, one at each end. These openings will accommodate photographic plate wells of various kinds and also a large air lock that is being designed. It is suggested that any other modifications to the target area be presented to E. Lofgren as soon as possible so that the modifications can be programmed with respect to operations. The same general policy holds for target location, viz: (a) Small targets - allocations in west tangent tank; and (b) Large targets - allocations in south tangent tank. The design of two general purpose magnets is in the final stages. Copper for the coils will be ordered soon. The characteristics of these magnets are given. Results of magnetic field measurements on the …