"This report presents the results obtained from pressure distribution tests on the fuselage of a PW-9 pursuit airplane in a number of conditions of flight. The investigation was made to determine the contribution of the fuselage to the total lift in conditions considered critical for the wing structure, and also to determine whether the fuselage loads acting simultaneously with the maximum tail loads were of such a character as to be of concern with respect to the structural design of other parts of the airplane. The results show that the contribution of the fuselage toward the total lift is small on this airplane" (p. 327).

Report presenting two blending equations that have been derived from an analysis based on certain assumptions relative to the cause of fuel knock. The main purpose of this study was to investigate the possibility of developing a method of predicting the knock ratings of fuel blends.

"The usefulness of the knock ratings of pure hydrocarbon compounds would be increased if some reliable method of calculating the knock ratings of fuel blends was known. The purpose of this study was to investigate the possibility of developing a method of predicting the knock ratings of fuel blends. Two blending equations have been derived from an analysis based on certain assumptions relative to the cause of fuel knock" (p. 1).

"The NACA has conducted an investigation to determine the performance that can be obtained from a multistage axial-flow compressor based on airfoil research. A theory was developed; an eight-stage axial-flow compressor was designed, constructed, and tested. The performance of the compressor was determined for speeds from 5000 to 14,000 r.p.m with varying air flow at each speed" (p. 81).

"The laws of conservation of mass, momentum, and energy are applied to the compressible flow through a two-dimensional cascade of airfoils. A fundamental relation between the ultimate upstream and downstream flow angles, the inlet Mach number, and the pressure ratio across the cascade is derived. Comparison with the corresponding relation for incompressible flow shows large differences. The fundamental relation reveals two ranges of flow angles and inlet Mach numbers, for which no ideal pressure ratio exists" (p. 123).

From Summary: "A V-type engine provided with a glass cylinder was used to study visually the lubrication characteristics of an aircraft-type piston. Photographs and data were obtained with the engine motored at engine speeds up to 1000 r.p.m. and constant cylinder-head pressures of 0 and 50 pounds per square inch. A study was made of the orientation of the piston under various operating conditions, which indicated that the piston was inclined with the crown nearest the major-thrust cylinder face throughout the greater part of the cycle. The piston moved laterally in the cylinder under the influence of piston side thrust."

A series of 11 fuels ranging in volatility and including various types of hydrocarbons were tested in a single tubular combustion chamber of a turbojet engine under inlet-air conditions simulating engine operation at two speeds at an altitude of 40,000 feet. Temperature-rise data at various fuel-air ratios were obtained for each set of air-flow conditions. Results regarding the effect of combustor inlet-air conditions on temperature rise, four different series of tests, and a review of some general considerations are provided.

The following documents were compiled into a quarterly report that was to be published in the Radiobiology Volume of the PPR. The following reports provide data from the Biology department of the University of Chicago between May and August of 1947.

Report discussing specifications for the design of a waste heat steam boiler "for the purpose of generating steam to operate a condensing steam turbine electric generator from the clean hot radioactive air that has cooled the atomic energy reactor of [a] laboratory under a pressure less than atmospheric."

Report presenting the results of an experimental investigation to determine the pressure-recovery and mass-flow characteristics of single and twin NACA submerged intakes on the sides of a fuselage at various angles of sideslip. Tests were conducted with single and twin submerged intakes on a model of a fighter-type airplane.

From summary: "A method for the preparation of normal uranyl carbonate has been developed. Heretofore, this compound has been known only as a rare, naturally occurring material." The report further discusses the physical properties of the compound, its solubility in water, and its interaction with sodium carbonate.

Report discussing a study to determine experimentally whether a low neutron binding energy must be assigned to Kr⁸⁷ to explain the neutron emission or whether the beta-decay energy is especially high, as well as to determine the fission yield of Br⁸⁷.

Report documenting the suitability of Mississippi for plant locations to produce synthetic liquid fuels, based on raw materials, water sources, and local interest.

The complexing of lanthanum by various anions and weak acids was investigated by observing the light absorption of the complex formed with thenoyltrifluoracetone (TTA). This species showed the properties needed for a satisfactory specgtrophotometric method of analysis.

From summary: "Various thermal and mechanical properties were measured for sintered tin oxide-matrix compacts which nominally were composed of 99 per cent by weight of tin oxide, SnO2, and one per cent by weight of zinc oxide ZnO...The tin oxide body might be expected to give good service under conditions of severe thermal shock and in an oxidizing atmosphere at temperatures up to 1500°F."

Report discussing progress made by the Chemistry Division (Section C-1) of the Argonne National Laboratory for the months of April, May and June, 1951. Information is divided into "Nuclear Chemistry and Radiochemistry" and "Basic Chemistry".

Report presenting an investigation in the 4- by 4-foot supersonic pressure tunnel at Mach number 2.01 to determine the effects of sweep angle and thickness ratio on the static lateral stability characteristics of a series of wings with taper ratio 0.2 and aspect ratio 3.5. The results are presented with little analysis.

Report describing the research and development activities related to nuclear chemistry and radiochemistry and basic chemistry conducted by the Argonne National Laboratory Chemistry Division, Section C-1.

A technique for the fusion welding of uranium has been under development and several methods of fusion welding have been investigated. The inert gas, shield arc method has proven to be the most satisfactory of the processes thus far examined. Uranium properly weld by this method was free from porosity, cracks, and oxide inclusions. Certain precautions and some special techniques were required to make good welds.

"Full-scale aircraft crashes were made to investigate the mechanism of the start and development of aircraft crash fires. The results are discussed herein. This investigation revealed the characteristics of the ignition sources, the manner in which the combustibles spread, the mechanism of the union of the combustibles and ignition sources, and the pertinent factors governing the development of a crash fire as observed in this program" (p. 547).

"Comparisons have been made of the shock phenomena and drag-rise increments for representative wing and central-body combinations with those for bodies of revolution having the same axial developments of cross-sectional areas normal to the airstream. On the basis of these comparisons, it is concluded that near the speed of sound the zero-lift drag rise of a low-aspect-ratio thin-wing and body combination is primarily dependent on the axial development of the cross-sectional areas normal to the airstream. It follows that the drag rise for any such configuration is approximately the same as that for any other with the same development of cross-sectional areas" (p. 519).

"A theoretical study is described of the aerodynamic characteristics at small angle of attack of a thin, double-wedge profile in the range of supersonic flight speed in which the bow wave is detached. The analysis is carried out within the framework of the transonic (nonlinear) small-disturbance theory, and the effects of angle of attack are regarded as a small perturbation on the flow previously calculated at zero angle. The mixed flow about the front half of the profile is calculated by relaxation solution of a suitably defined boundary-value problem for transonic small-disturbance equation in the hodograph plane (i.e., the Tricomi equation)" (p. 547).

The annealing or heat treatment of uranium in any medium other than a good vacuum or purified helium atmosphere, will lower the room temperature properties of ultimate strength, hardness and elongation. In general, the elongation of vacuum annealed uranium exceeds considerably the elongation of air or salt annealed uranium. Any annealing medium which permits contact of the uranium metal with atmospheric gases tends to produce low elongation and ductility and a lowering of the ultimate strength. The above is true for uranium in any solid form, whether it is rolled sheet, cast bars or plates, rolled rod, or extruded shapes. Annealing in the molten salt bath (65% potassium carbonate and 35% lithium carbonate), which is used by Los Alamos and other laboratories concerned with the fabrication of uranium, produces the lowest elongation or ductility and ultimate strength when compared to similar properties of metal annealed in the other media examined. Mass spectrometer analyses of the dissolved gases present in high ductility and low ductility uranium indicate that dissolved hydrogen is probably the chief cause of low physical properties.

Several improvements have been made in the gamma scintillation counter (GSC). The Model V gamma scintillation counter uses a canned thallium activated sodium iodide crystal as a detector. Although the electronic components remain unchanged, a modification of the sample support has been made to improve reproducibility of geometry. To assure comparable results between various counters, they must be operated at the same energy threshold and counting yield. Methods have been developed to assure operation at a preferred energy threshold of 0.1 Mev and an arbitrarily fixed counting yield of 3.36% for Cs-Ba-137. Partial pulse height discrimination against U 237 is also accomplished.