Report issued by the Bureau of Mines over investigations of coking coal reserves of Sequatchie County, Tennessee. Testing to determine suitability for producing metallurgical coke is also presented. This report includes tables, graphs, maps, illustrations, and photographs.

From introduction: "This report describes the second phase of the work on the application of protective coatings to uranium by vapor deposition to reduce or prevent its corrosion by water."

Abstract: "Refinement of grain size of the base uranium-chromium eutectic alloy (uranium-5 w/o chromium) by ternary additions is discussed. Thirteen additions to the base alloy were investigated, and three additions were found to exhibit worthwhile grain-refinement tendencies. The three alloys, uranium-5 w/o chromium-0.2 w.o molybdenum, uranium-5 w/o chromium-0.2 w/o germanium, and uranium-5 w/o chromium-0.2 w/o niobium, were heat treated to produce final grain-size structures of between 0.015 and 0.033 mm."

The following report focuses on an investigation made to determine if vacuum melting was an absolutely necessary step in the metallurgical process of melting and casting uranium.

Abstract: "A study of plastic flow during the extrusion of tubing was made by extruding colored Plasticine billets in a small-scale extrusion press. Decreasing the included angle of the conical die and tapering the ram end of the billet decreased the amount of coextrusion of the backer block into the tubing, lubricating the billet also decreased coextrusion."

The following report studies the dissolution of aluminum-canned thorium, providing results that suggest a dissolution cycle that permits the separation of the canned-slug components.

Introduction: Thorium and rare-earth metals have come into strategic importance in this country in the last few years with the potential use of thorium in the production of atomic power and the development of new uses for the rare earths in the aircraft industry.

Abstract: "By a simple illustration it is pointed out that, conceivably, the real coupled character of the general magnetohydrodynamic equations may lead to much slower instability growth rates, if not stabilization, than predicted from the linearized set of equations."

The following report provides results from investigations of torsional vibration stresses in the drive shafts of two Westinghouse motor generator sets in 1952.

From Introduction: "The purpose of this paper is to present and discuss skin temperature measurements from two flight tests. Temperature measurements were obtained to a Mach number of 5.4 on the first flight and to a Mach number of 10.4 on the second flight."

"An investigation was made of a 1/25-scale dynamically similar model of a 255,000-pound transport airplane in order to study its behavior when ditched. The model was free-launched from the Langley tank no. 2 monorail carriage into calm water. Various landing attitudes, flap settings, speeds, and configurations were investigated" (p. 1).

Report presenting fluid-dynamics studies of a tank of fineness ratio 7.0 which was pylon mounted on a simplified two-dimensional flutter model in order to determine the effects of the fluid on flutter. The flutter speed was determined for three cases: with various amounts of water in the tank, with weights with the same mass and moment of inertia as the fluid considered to be a frozen solid, and with weights with the same mass and moment of inertia as the actual fluid. Results regarding the flutter speed, effects of inertia on flutter, and amplitude of flutter are provided.

A flight investigation was made at altitudes of 40,000, 25,000 and 15,000 feet to determine the horizontal-tail loads of the Bell X-5 research airplane at a sweep angle of 58.7 deg over the lift range of the airplane for Mach numbers from 0.61 to 1.00. The horizontal-tail loads were found to be nonlinear with lift throughout the lift ranges tested at all Mach numbers except at a Mach number of 1.00. The balancing tail loads reflected the changes which occur in the wing characteristics with increasing angle of attack. The nonlinearities were, in general, more pronounced at the higher angles of attack near the pitch-up where the balancing tail loads indicate that the wing-fuselage combination becomes unstable.

Report presenting an examination of creep and thermal buckling in order to determine their effect on the design of structures for high-speed aircraft. Consideration is given to the use of insulation as a means of alleviating the effect of aerodynamic heating. Creep did not appear to be a significant factor, but thermal buckling may have a substantial effect on the structural design.

From Summary: "A flight test has been conducted to determine the longitudinal stability and control characteristics of a 0.125-scale model of the McDonnell F-101A airplane for the Mach number range between 0.82 and 1.84. The variation of lift-curve slope with Mach number was gradual with a maximum value of 0.107 occurring at a Mach number of 0.95. The minimum drag coefficient (including base and internal drag) has a value of 0.020 at a Mach number of 0.87. The drag rise begins at a Mach number of 0.90, and at Mach number of 1.10 the minimum drag is 0.070. Above this Mach number there is a gradual increase in minimum drag coefficient to a value of 0.074 when the Mach number is 1.83."

Report discussing testing on a model of the General Electric P-1 nuclear powerplant to determine its internal aerodynamic characteristics. The main purposes of testing were to measure the mass-flow distribution of air, to measure the total-pressure losses for the duct components and complete model, and to determine modifications necessary to attain the desired performance characteristics.

Report presenting heat-transfer data obtained in free flight at supersonic Mach numbers up to 4.90 and local Reynolds numbers per foot up to 27.7 million. Two 20 degree-included-angle cone-cylinder models were launched from a carrier airplane at 36,000 feet of altitude. Results regarding primary data and heat-transfer results are provided.

Memorandum presenting a theoretical analysis of an airplane automatic control system incorporating a compensating network. The compensating network is a computing network that has characteristics that are the inverse of the airframe; consequently, airplane dynamics are eliminated from the system response. Results regarding the displacement control system, the velocity command system, and the acceleration control system are provided.

Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effect of changes in body cross-section shape on the aerodynamic characteristics of bodies and wing-body combinations. A series of 13 bodies of a given length and volume but various cross-section shapes were tested at a Mach number of 2.01. The results showed that changes in drag at zero lift due to changes in body cross-section shape from the basic circular shape are small and of the same order as the test accuracy.

Report presenting a comparison of the buffet loads measured on wind-tunnel models with loads measured in flight, which indicate that a simple strain-gage measurement can be used in wind tunnel testing that can be used to predict the wing buffet loads on the airplane. The technique appears to be usable for both unswept and swept configurations.

Report presenting an investigation of aircraft which are required to maneuver rapidly at extreme altitudes, which involves reaching maximum loads at high angles of attack. Load information is necessary for that flight condition and for aircraft that reach their maximum loads at high speed and high dynamic pressures. Results regarding the wings and wing-body combinations are provided.

Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effects of body indentation on the minimum drag and maximum lift-drag ratio of a 60 degree swept-wing-body combination. A secondary goal of the tests was to determine the effect on the maximum lift-drag ratio of modifying the inboard plan form of the 60 degree swept wing. Lift, drag, and pitching-moment data are presented.

Report presenting an investigation to show the effects of systematic changes of leading-edge radius, aspect ratio, Reynolds number, and Mach number on the static longitudinal aerodynamic characteristics of sweptback wings in the 19-foot pressure tunnel. Results regarding the effects of leading-edge radius and aspect ratio and effect of Reynolds number and Mach number are provided.

Report presenting a free-jet investigation of the performance, burner-shell cooling, and ignition characteristics of a flight-weight 48-inch-diameter XRJ47-W-5 ramjet engine at an inlet Mach number of 2.75 and an angle of attack of 3 degrees. Data were obtained over a range of altitudes, inlet temperatures, and fuel-air ratios.