Report issued by the Bureau of Mines over studies conducted on manganese deposits of Aroostook County, Maine. Descriptions of the deposits, and the results of the study are presented. This report includes tables, maps, illustrations, and photographs.

From abstract: Radioactive manganese deposits have been found in two swamps and at one locality on the northeast bank of the Rio Itapicuru near Mosquete, municipio of Itapicuru, State of Bahia, Brazil. The occurrences are related to warm springs and consist of surficial manganiferous sinter and of sandstone impregnated with manganese.

Report discussing performance estimates for several airplanes using General Electric AC-210 ramjet nuclear-powered engines. Assumptions used for designing the engines, radiation shield, and airframe are described. Potential tradeoffs in regards to power and weight reduction are also discussed.

Abstract: A low-level airborne radioactivity survey of parts of Beaverhead and Madison Counties in southwestern Montana was undertaken from June 6 to October 14, 1955. Flying centered around the Ruby Range-Sweetwater Basin area and concentrated on the Precambrian metamorphic complex and Tertiary lake-bed sediments. No commercial uranium deposits were discovered, and no extensions were found of the few known small occurrences. Five areas of high background detected through the survey were investigated on the ground.

From abstract: This report describes geologic and oceanographic factors relevant to the selection of a site in northwestern Alaska, at which an experimental harbor can be created by the explosion of a nuclear device. Part I describes the results of a preliminary survey of the entire coastal and offshore region between Nome and Point Barrow: Part II consists of a more detailed evaluation of the Cape Thompson-Cape Seppings area; and Part III is a theoretical consideration of the effect of the ocean upon the temperature and distribution of permafrost. The report is based entirely upon the study of published and unpublished reports, field notes, and maps, interviews with the few geologists who have visited the region, and the interpretation of aerial photographs.

Introduction: The experimental work reported here was undertaken as a part of the over-all design and development program for a nuclear reactor pressure vessel.

A plot of overpressure versus distance is presented for the fractional psi pressure level. The plot provides a rapid and simple means of estimating the permissible yield at any distance from settled areas.

Memorandum presenting a transonic flutter investigation of models of the wing of a current fighter airplane. The models were dynamically and elastically scaled in accordance with criteria which include a flutter safety margin. Results regarding the presentation of data, interpretation of results, wings without leading-edge chord-extensions, and wings with leading-edge chord-extensions are provided.

Report presenting testing of gaseous hydrogen fuel burned in a connected-pipe combustor with a cross section equal to 35 degrees sector of a 28-inch diameter. Eleven shrouded fuel-injector configurations were used to obtain combustion data at specified high-altitude ramjet combustor conditions. Results regarding shroud air blockage, mixing tabs, higher equivalence-ratio burning, injector size, flameholder durability, burner length, combustion efficiency, and temperature profile are provided.

Memorandum presenting an investigation of the steady-state wing loads conducted on a Boeing B-52 airplane over a range of Mach numbers and altitudes. Results regarding flight tests and air-load calculations are provided.

Report presenting testing of specimens of various metals in selected geometric configurations exposed to liquid fluorine under controlled conditions of flow and pressure. None of the samples eroded, decomposed, or exhibited any measurable physical or chemical changes.

From Summary: "The effect of engine momentum on the longitudinal and directional stability of aircraft in steady rolling maneuvers has been investigated. The results presented indicate that the gyroscopic moments produced on the aircraft by a rotating engine in rolling maneuvers can have an appreciable effect on the range of rolling velocities for which longitudinal or directional instability might occur."

From Introduction: "First, an analysis of loads transmitted to the hub by balanced blades will be given. In the second section, the additional loads transmitted to the hub in a direction normal to the plane of rotation of the blades by imbalances in a rotor are derived. In the entire analysis, the results are given in terms of the forces transmitted to the hub by a single rotating helicopter blade in flight, and these are regarded as known or given."

Report presenting an investigation in the 2- by 2-foot transonic wind tunnel to determine the aerodynamic effects of fixing boundary-layer transition in a forward location on two unswept-wing models differing only in size and with unswept wings of aspect ratio 3.09 with sharp leading edges. Results regarding effects of fixing transition and wall effects in the Ames 2- by 2-foot transonic wind tunnel for an unswept-wing-body model are provided.

Note presenting the minimum thickness of the oil film as used as a basic variable in performance curves of plain journal bearings under steady load. The load capacity and the predicted film thickness at the hook point of the friction curves are shown to correlate with the peak-to-valley values of surface roughness when misalignment is absent.

Note presenting hot-wire anemometer measurements of the turbulent shearing stress in a turbulent boundary layer on a yawed flat plate. The measured velocity profiles are used to calculate the shear distribution and the result is compared with the result of experimental shear measurements.

Report presenting an experimental study of the drag of flat plates and cylinders in the slipstream of a hovering rotor. The dynamic pressure profile of the slipstream for stations close to the rotor was characterized by low or slightly negative values in the center, a rise to a peak near the edge of the slipstream, and a rapid decrease to small negative values farther from the center. Results regarding the drag-to-thrust ratio, ratio of percent thrust loss to percent blocked area, and drag coefficients are provided.

Note presenting a method for the design and analysis of two-dimensional subsonic-flow passages with isentropic nonviscous flow. The method is based on the relation between the pressure change across a stream tube and the centrifugal force resulting from the curvature of the flow. In an example, the method was applied to the design of an expanding elbow at each of two Mach numbers.

An approximate theory is developed for predicting the rate of heat transfer to the stagnation region of blunt bodies in hypersonic flight. Attention is focused on the case where wall temperature is small compared to stagnation temperature. The theoretical heat-transfer rate at the stagnation point of a hemispherical body is found to agree with available experimental data. The effect of yaw on heat transfer to a cylindrical stagnation region is treated at some length, and it is predicted that large yaw should cause sizable reductions in heat-transfer rate.

Report presenting an experimental investigation of the equivalence relationship and the related theory for lifting forces proposed by transonic slender-body theory. Two different models with different dimensions are tested over a range of Mach numbers. Results regarding flow equivalence at sonic speed, Mach number range of equivalence, and lifting pressures at transonic speeds are provided.

Report presenting a study of the shape, growth, and formation rate of turbulent bursts in supersonic boundary layers using spark shadowgraphs of small gun-launched models in free flight through still air. The model shapes include cones, ogive-cylinders, and hollow cylinders aligned with the stream. Results regarding the burst thickness profiles, burst plan form and transverse growth, three-dimensional burst shape, burst upstream-edge velocity, burst longitudinal growth rate, burst downstream-edge velocity, burst formation rate, and observations from the shadowgraphs are provided.

Note presenting heat-transfer data evaluated from temperature time histories on a cooled cylindrical model with a cone-shaped nose and with turbulent flow at Mach numbers 3.00, 3.44, 4.08, 4.56, and 5.04. The experimental data were compared with calculated values using a modified Reynolds analogy between skin friction and heat transfer. Results regarding the air flow and temperature-distribution results and heat-transfer results are provided.

A series of papers describing a system that will automatically record as many as 300 pressures, 200 voltages, and 24 frequencies in as little as 30 seconds to an accuracy of 0.15 percent or better of full-scale range. The information is able to be used in any high-speed, general-purpose digital computer. The computer will accept the encoded data produced by the recording system and automatically calibrates it, takes averages, forms ratios, and does terminal calculations such as mass flow, momentum, distortion numbers, drag coefficients, thrust, specific fuel consumption, and efficiency.

From Introduction: "In the turbulent case, however, the results of the various analyses disagree markedly because of the different assumptions made by various authors. These analyses are reviewed in references 1 to 3. The analysis is extended to flow and heat transfer in a boundary layer at high Mach numbers in this paper. (Some preliminary results were presented in ref. 11.)"