This report for May, 1947 describes progress regarding analytical work, chemical work, beta-counting methods of analysis, ore-dressing and pyrometallurgical studies, and pyrometallurgical work.

Abstract: "Variations in receiver slot design produce changes in quantity and quality of product and recycle, not only instantaneously, but also as a function of time in approaching equilibrium. The case of fixed feed concentration and fixed inventory of Uranium is described here for standard and Dip-Lip wider R slot receivers. The effects of the two types of receivers on recycle and product X and W concentrations, X production rate, plant X utilization efficiency, integrated X production and effective mass output are shown graphically."

Report discusses the development and testing of a rocket-propelled test vehicle to investigate aerodynamic control effectiveness at high subsonic, transonic, and supersonic speeds. Modifications to the section thickness and wing sweepback to improve performance are also described. A description of the vehicle, instrumentation, accuracy, and evaluation of testing results is included.

Abstract: The procedures recommended for analysis in Department 190 Laboratories, in the Limits Control Laboratory, and in the Analytical Development Laboratories, of all process materials from the HCP cycle are presented in a stepwise manner. A description of the characteristics of each sample type along with a brief description of factors involved in the Analytical Quality Control program is included.

Report presenting wind-tunnel testing to determine the low-speed lift, drag, and pitching-moment characteristics of a 40 degree sweptback wing with high-lift and stall-control flaps and a fuselage with a fineness ratio of 10.2 to 1. Low, medium, and high-wing-fuselage combinations were tested at high Reynolds numbers. Results regarding the high-lift and stall-control flaps and wing-fuselage combinations are provided.

Report presenting tests of an NACA 4-(5)(08)-03 two-blade propeller in the 8-foot high-speed tunnel for blade angles of 45 and 60 degrees extending the Mach number range from that of previous tests of the propeller up to Mach number 0.913. When the forward speed was increased from a low value to a forward Mach number of 0.90, the loss in peak efficiency was found to be not more than 47 percent.

"The spin and recovery characteristics of the Curtiss-Wright XP-87 airplane, as well as the spin-recovery parachute requirements, the control forces that would be encountered in the spin, and the best method for the crew to attempt an emergency escape, are presented in this report. The characteristics were estimated rather than determined by model tests because the XP-87 dimensional and mass characteristics were considered to be noncritical and because data were available from model tests of several similar airplanes. The study indicated that the recovery characteristics of the airplane will be satisfactory for all loadings if the controls are reversed fully and rapidly" (p. 1).

Report discussing testing on a 42 degree swept-back wing to determine its low-speed aerodynamic characteristics in pitch and yaw at high Reynolds numbers. The main effect of increasing the Reynolds number was delayed wing stalling to higher angles of attack. Roughness on the wing leading edge also had a large adverse effect on lift, drag, and pitching-moment characteristics at higher Reynolds numbers.

From Summary: "An investigation was conducted to determine the coolant-flow distribution, the cylinder temperatures, and the heat rejections of the V-1650-7 engine . The tests were run a t several power levels varying from minimum fuel consumption to war emergency power and at each power level the coolant flows corresponded to the extremes of those likely to be encountered in typical airplane installations, A mixture of 30-percent ethylene glycol and 70-percent water was used as the coolant. The temperature of each cylinder was measured between the exhaust valves, between the intake valves, in the center of the head, on the exhaust-valve guide, at the top of the barrel on the exhaust side, and on each exhaust spark-plug gasket."

Wind tunnel tests haved been made at low speed to various small-scale models of swept-back, swept-forward, and yawed wings. Tests covered changes in aspect ratio, taper ratio, and tip shape.

Report presenting part of the results obtained to determine the effects of compressibility at high Mach numbers on a model of the Bell XS-1 transonic research airplane. General trends that can be qualitatively analyzed for level-flight Mach numbers up to 0.93 are given. Results regarding force characteristics and a comparison of results with wing-flow investigation are also provided.

Redux is a thermosetting synthetic resin manufactured by the Resinous Products & Chemical Co., Washington Square, Philadelphia 5, Pa. According to the manufacturer, it is intended for bonding metal to metal and metal to wood. It was apparently intended to replace rivets in aircraft structural parts and recent information indicates that a British airplane, the DeHaviland Dove, is in production using this resin. The adhesive was originally developed in England by Aero research Ltd. Experience at this laboratory has been confined to use of the resin for bonding electrical grade silicon steel laminations. Very strong bonds have been obtained under properly controlled conditions. The bond strength is sufficient to tear 29 gauge (.014") steel when attempting to peel off individual laminations. The bond is sufficiently homogeneous to prevent leaks parallel to the plane of the laminations into a high vacuum system. Experiments at the laboratory have been designed to test the adhesive for use in bonding the laminations which form the pole tips and vacuum chamber lids for the synchrontron magnet.

Report presenting testing of a standard turbojet engine by water injection at the inlet of the axial-flow compressor in the altitude wind tunnel. Engine performance at 7600 rpm was obtained over a wide range of water-air-pressure ratios and ram-pressure ratios. Results regarding the engine-component performance are also provided.

Report discussing an investigation on the effect of engine skew on the directional and lateral control characteristics of a single-engine airplane with a single-rotating propeller. The estimated and test results showed an advantage to skewing the propeller, as it assists with overcoming inadequate rudder control in power-on flight and aileron control, especially with flaps deflected.

"A compilation of free-spinning-airplane model data on the spin and recovery characteristics of 111 airplanes is presented. These data were previously published in separate memorandum reports and were obtained from free-spinning tests in the Langley 15-foot and the Langley 20-foot free-spinning tunnels. The model test data presented include the steady-spin and recovery characteristics of each model for various combinations of aileron and elevator deflections and for various loadings and dimensional configurations" (p. 1).

Report presenting an investigation of two 10-foot-diameter three-blade propellers to determine the effect of swept-back blade tips on propeller aerodynamic characteristics. Results regarding the effect of swept-back tips on maximum efficiency and constant-power propeller operation are provided.

Report discussing assaying techniques used in the Department of Metallurgy at the Massachusetts Institute of Technology, as well as the equipment used for the techniques.

Report discussing tests that were carried out to determine if a few parts per million of boron can be removed directly from beryllium oxide powder without chemically changing the BeO during the process.

Memorandum presenting high-speed wind-tunnel testing to investigate the aerodynamic characteristics at subsonic speeds of two symmetrical double-wedge airfoil sections of 4- and 6-percent-chord thickness suitable for application to supersonic aircraft. Section coefficients of lift, drag, and quarter-chord pitching moment are presented for a moderate range of angles of attack at Mach numbers up to approximately 0.93. The double-wedge airfoil exhibits no characteristics other than those common to the usual subsonic profile which would contribute to unsteady or uncontrollable flight at subsonic speeds of aircraft employing such a section for lifting surfaces.

In accordance with a request of the Bureau of Aeronautics, Navy Department, tests were performed in the Langley 20-foot free-spinning tunnel to determine the spin and recovery characteristics of a 1/24 scale model of the Grumman XTB3F-1 airplane. The airplane is a two-place, midwing torpedo bomber equipped with a tractor propeller and an auxiliary jet engine. The effect of control setting and movement on the erect and inverted spin and recovery characteristics of the model were determined for the normal loading.

"Results are presented of an investigation that has been undertaken to develop theoretical methods of treating the motions of hydrofoil systems and to determine some of the important parameters. Variations of parameters include three distributions of area between the hydrofoils, two rates of change of downwash angle with angle of attack, three depths of immersion, two dihedral angles, two rates of change of lift with immersion, three longitudinal hydrofoil spacings, two radii of gyration in pitching, and various horizontal and vertical locations of the center of gravity. Graphs are presented to show locations of the center of gravity for stable motion, values of the stability roots, and motions following the sudden application of a vertical force or a pitching moment to the hydrofoil system for numerous sets of values of the parameters" (p. 1).

Introduction. The main objective of the Metallurgical Project was the preparation of large quantities of plutonium 239, an isotope of element 94, by the interaction of neutrons and uranium. At the beginning, only predictions of its chemical and biological properties could be made since it is a new element. It was predicted that it would be toxic to tissue by virtue of its high atomic weight, and in addition, that it would be toxic by virtue of its radioactivity. Thus, the preparation and use of the element on a large scale meant the manipulation of, and possible exposure to, toxic quantities. It was, therefore, of practical importance to obtain data which would elaborate on the predicted toxicity. The objectives of the work reported here were to establish the acute toxicity of plutonium in experimental animals and to study the distribution of the element in the body after the administration of a wide range of doses. In the interest of economy of what was, at that time, a rare substance, and of animals and facilities, these two objectives were frequently pursued in the same experiment. The information obtained from the separate experiments is therefore frequently incomplete in one or another respect. …

Powered models of three different flying boats were landed in oncoming wave of various heights and lengths. The resulting motions and acceleration were recorded to survey the effects of varying the trim at landing, the deceleration after landing, and the size of the waves. One of the models had an unusually long afterbody. The data for landing with normal rates of deceleration indicated that the most severe motions and accelerations were likely to occur at some period of the landing run subsequent to the initial impact.

Report presenting a test-stand investigation conducted on a rectangular ramjet engine design for installation in an aircraft wing. The engine operated without excessive engine noise or vibration over the entire range of operating conditions. Results regarding inlet velocity, exhaust flame characteristics, fuel-air ratio, and total-temperature rise are provided.