Memorandum presenting the buffet characteristics of a scale model of an attack airplane over a range of Mach numbers. The wing had a modified delta plan form with an NACA 0008 airfoil section at the root and an NACA 0005 airfoil section at the tip, a leading-edge sweep of 41.11 degrees, an aspect ratio of 2.91, and a taper ratio of 0.226. Results regarding the frequency spectrum of bending moment, effect of density on root-mean-square bending moment, system damping coefficients, and buffet input force are provided.

"On the basis of a recently developed theory for finite sweptback wings at supersonic speeds, calculations of the supersonic wave drag at zero lift were made for a series of wings having thin symmetrical biconvex sections with untapered plan forms and various angles of sweepback and aspect ratios. The results are presented in a unified form so that a single chart permits the direct determination of the wave drag for this family of airfoils for an extensive range of aspect ratio and sweepback angle for stream Mach numbers up to a value corresponding to that at which the Mach line coincides with the wing leading edge. The calculations showed that in general the wave-drag coefficient decreased with increasing sweepback" (p. 1).

Report presenting testing of a series of thin, triangular plan-form wings, including eight triangular wings of vertex angles and three swept-back wings with circular-arc sections. Results regarding lift, center of pressure, and ideal operation of different types of wings are provided.

Report presenting the results of a series of exploratory flights on a 35 degree swept-wing airplane up to Mach number 1.09 to show the effects of compressibility on imposing maneuverability limits. Results regarding the maneuvering accelerations and buffet boundary are provided.

Report presenting an investigation of the effects of three centrally mounted wing-tip tanks on the aerodynamic characteristics of a cambered wing with an aspect ratio of 10 and 35 degrees of sweepback. Testing occurred over a range of Mach and Reynolds numbers and lift, drag, and pitching-moment were measured.

"An investigation of the static and dynamic longitudinal stability characteristics of 1/3.7 scale rocket-powered model of the Bell MX-776A has been made for a Mach number range from 0.8 to 1.6. Two models were tested with all control surfaces at 0 degree deflection and centers of gravity located 1/4 and 1/2 body diameters, respectively, ahead of the equivalent design location. Both models were stable about the trim conditions but did not trim at 0 degree angle of attack because of slight constructional asymmetries" (p. 1).

"An investigation was conducted to compare the knock-limited performance of a 20-percent triptane blend in 28-K fuel with that of 28-R and 33-R fuels at high engine speeds, cruising speeds, and two compression ratios in an K-1830-94 multicylinder engine. Data were obtained with the standard compression ratio of 6.7 and with a compression ratio of 3.0. The three fuels were investigated at engine speeds of 1800, 2250, 2600, and 2800 rpm at high and low blower ratios" (p. 1).

Report presenting a continuous sampling-probe technique used to determine the percentage of JP-5 fuel spray evaporated under conditions common in ramjet engines. Fuel was injected contraststream from a multiple-orifice injector and sampling data were obtained at several distances downstream of the injector. An expression is generated for a description of this phenomenon.

Memorandum presenting an investigation in the 4- by 4-foot supersonic pressure tunnel to determine the effects of various vertical locations of the wing and horizontal tail on the aerodynamic characteristics in pitch and of a supersonic airplane configuration at Mach number 2.01. The model was equipped with a wing and horizontal tail, each having a 45 degree sweep and an aspect ratio of 4. The configurations investigated included a high-wing, a mid-wing, and a low-wing arrangement, each with four different horizontal tail locations varying from a position 0.208 semispan below to 0.556 semispan above the body center line.

An investigation was made to determine the effects of varying the spacing between the nozzle blades and the turbine blades of a turbo-jet engine on turbine-blade vibration for four turbine-blade designs of different degrees of stiffness. In general, there was a tendency toward increase in occurrence of vibration with decrease in spacing. The effect was most evident in the case of the turbine blades that had greater stiffness.

Report presenting an investigation of the performance of the Westinghouse XJ34-WE-32 engine with afterburner operative in the altitude wind tunnel at a range of simulated altitudes and Mach numbers. A study was also made to prevent the clogging of the fuel-injection holes due to coke or carbon deposits, which occurred during initial testing. Results regarding the characteristics of fuel manifold coking, influence of fuel distribution on performance, afterburner inlet conditions, effect of altitude and flight Mach number, afterburner pressure losses, and afterburner ignition and blowout are provided.

Report presenting testing of a rocket-propelled model of an airplane with an arrow wing with a 55 degree leading-edge sweep and a flat-sided fuselage mounting swept horizontal and vertical tails using the pulsed-control technique at a range of Mach numbers. Results regarding longitudinal trim, lift and stability, drag, lateral force, and thrust and jet effects are provided.

Report presenting an investigation of the buffet characteristics of a model of an attack airplane at a variety of Mach numbers. The wing had a modified delta plan form with two NACA airfoils, a leading-edge sweep of 41.11 degrees, an aspect ratio of 2.91, and a taper ratio of 0.226. Results regarding frequency spectrum of bending moment, effect of density on root-mean-square bending moment, system damping coefficients, and buffet input force are provided.

Report presenting an investigation in the 16-foot transonic tunnel at a variety of Mach numbers to determine the interference effects of a hot jet exhaust on the pressure distribution of a 60 degree delta wing. Results regarding the tabulated pressure coefficients for the wing and nacelle for the complete range of test conditions are provided.

Report issued by the Oak Ridge National Laboratory discussing quarterly progress made by the Molten-Salt Reactor Program. Descriptions of the progress and studies conducted is presented. This report includes tables, illustrations, and photographs.

From abstract: "Various physical and mechanical properties have been determined for high- and low-carbon base uranium, uranium-chromium, and uranium-zirconium alloys. These data complement those obtained at ANL on the same materials."

From abstract: "The purpose of this note is to consider the feasibility of conducting kiloton-weapons tests in underground holes sufficiently deep so that the explosion will be effectively contained. Such a shot would have the advantage that it could be detonated independently of weather conditions, and thus would allow greater freedom in the test program."

This report discusses the state of stress caused by pressure in process tubes, elaborating on five "theories of failure" that each explain the stress in process tubes in a different manner. These theories, which are depicted in a graph, include maximum normal stress, maximum strain, maximum shear stress, maximum strain energy, and maximum strain energy of distortion.

The following report describes data from the continuation of investigations which led to the observation and characterization of five artificial radioactive chains collateral to the natural radioactive families that has lead to the partial identification of one additional chain, collateral to the actinium family.

Report discussing the status of ductile zirconium preparation by the National Research Corporation up to February 20, 1950.

From Abstract : "The solubilities of the individual rare earth lactates and α-hysroxyisobutyrates in water at 20 and 60° were determined for comparison with the rare earth glycolate solubilities determined earlier."

The four types of respirator cartridges used at the 202 S Building were tested against aerosols found at that location, and in the laboratory against non-radioactive gaseous ruthenium tetroxide. Positive penetration of two types of cartridges was shown with one process aerosol. Gaseous ruthenium tetroxide penetrated all types of cartridges tested. Leaks were found in some of the cartridges. Particle size of aerosol particles was measured by means of cascade impactor samples and electron photomicrographs. A high percentage of the aerosol particles was found to be less than 0.2 microns in diameter. Ru¹⁰³ + Ru¹⁰⁶ and Zr⁹⁵ + Nb⁹⁵ were shown to be present in the process aerosol by gamma ray spectrometer analysis. Possible causes of penetration of respiratory equipment by ruthenium are discussed and suggestions made for alleviating the problem.

The calibration of mercury vapor detectors has always posed a problem because of the difficulty of generating known concentrations of mercury vapor in air. The purpose of this study was to design an apparatus that would generate and chemically measure known concentrations of mercury vapor in air for calibration work.

Consideration has been given to various forms of fissionable material for use in atomic reactors, including the pure metals, their alloys and compounds. Of particular interest is the dioxide of uranium which is refractory and corrosion resistant in some environments.The oxide is useful in both granular and bulk forms. Small grains of uranium oxide can be mixed with other materials to form matrix type elements where they serve either as a convenient or necessary form of fuel or fertile material. For other applications the oxide may be fabricated in bulk form such as pellets, rods, plates, or blocks.There is a need for knowledge of the properties of the properties of this oxide, particularly as it affects fabrication in the various forms required. This knowledge is also required by reactor designers and engineers. There is in addition a challenging field for basic studies of sintering rates, oxidation behavior and other phenomena. Fabrication techniques have been developed to produce uranium oxide in various forms with consideration given to the economy of production. The continued application of basic knowledge of these materials has led to simpler. more practical means of fabrication and has thus widened the scope of their use in atomic reactors.