Report presenting the lift, drag, and pitching-moment characteristics of a wing-fuselage combination employing a wing with the leading edge swept back 63 degrees and cambered and twisted for a uniform load at a lift coefficient of 0.25 and Mach number 1.53. The experimental results are compared to those from other investigations. A maximum lift-drag ratio of 8.9 and a minimum drag coefficient of 0.0145 was obtained.

From Summary: "A method is given for determining the horizontal tail loads in maneuvering flight. The method is based upon the assignment of a load-factor variation with time and the determination of a minimum time to reach peak load factor. The tail load is separated into various components. Examination of these components indicated that one of the components was so small that it could be neglected for most conventional airplanes; therefore, the number of aerodynamic parameters needed in this computation of tail loads was reduced to a minimum. In order to illustrate the method, as well as to show the effect of the main variables, a number of examples are given. Some discussion is given regarding the determination of maximum tail loads, maximum pitching accelerations, and maximum pitching velocities obtainable."

Memorandum presenting an investigation of 4811C ceramic blades and the problems involved in the adaption of ceramic materials to stressed turbine components. Results regarding spin tests and rotating heat-shock runs are provided.

The following report describes the electron spectrum of protactinium derived from 23 minute thorium 233 that was produced by neutron capture in stable thorium.

Report discusses the results of testing to determine the low-speed longitudinal stability characteristics and spanwise distribution of load of a wing model with the leading edge swept back 63 degrees, an aspect ratio of 3.5, and a large amount of twist and camber. The results are compared to tests of a model of an untwisted and uncambered wing of identical plan form. Measurements of force, pressure-distribution, and comparison of theoretical and experimental span loading are described.

An investigation was conducted to determine the effects of water injection on the over-all performance of a modified J33-A-27 turbojet-engine compressor at the design equivalent speed of 11,800 rpm. The water-air ratio by weight was 0.05. With water injection the peak pressure ratio increased 9.0 per- cent, the maximum efficiency decreased 15 percent (actual numerical difference 0.12), and. the maximum total weight flow increased 9.3 percent.

"Investigations have been conducted to determine by means of total-pressure surveys the boundaries of single and twin jets discharging through convergent nozzles into quiescent air. The jet boundaries for the region from the nozzle outlets to a station 6 nozzle diameters downstream are presented for nozzle pressure ratios ranging from 2.5 t o 16.0 and for twin-Jet nozzle center-line spacings ranging from 1.42 to 2.50 nozzle diameters. The effects of these parameters on the interaction of twin Jets are discussed" (p. 1).

Memorandum presenting an investigation to determine the static directional stability of a fuselage typical of tandem helicopters. The model consisted of a body with an elliptical cross section, a rear rotor pylon which was faired to form a large vertical tail with a very thick airfoil section, and a small horizontal tail mounted at about the midpoint of the height of the vertical tail. Results regarding the stability of the original model, the causes of low directional stability, and tests of some practical modifications of increasing directional stability are provided.

Report presenting a wind-tunnel investigation of the longitudinal characteristics of a wing-body combination with a wing with leading edge swept back 63 degrees. Lift, drag, and pitching-moment measurements were made over a range of Mach and Reynolds numbers. Results regarding the general characteristics and effect of Reynolds number are provided.

Report presenting an investigation in the free-flight tunnel to study the dynamic stability characteristics at low speeds of a winged tow-target model, the wings of which were free to float about a spanwise axis. Results regarding the wing panels fixed rigidly to the fuselage, wing panels hinged to move together, and wing panels hinged independently are provided.

"An experimental investigation of the effects of injecting a water-alcohol mixture of 2:1 at the compressor inlet of a centrifugal-flow type turbojet engine was conducted in an altitude test chamber at static sea-level conditions and at an altitude of 20,000 feet with a flight Mach number of 0.78 with an engine operating at rated speed. The net thrust was augmented by 0.16 for both flight conditions with a ratio of injected liquid to air flow of 0.05. Further increases in the liquid-air ratio did not give comparable increases in thrust" (p. 1).

Report presenting a low-speed wind tunnel investigation to determine the relationship between the flap effectiveness and the horizontal and vertical position of a partial-span single slotted flap on a sweptback wing-fuselage combination. Results regarding maximum lift, lift increment, and pitching moment are provided.

Report presenting an investigation of the effects of several molding conditions on the physical properties of laminates prepared with Fiberglass 181 glass fabric and Bakelite XRS-81 unsaturated-polyester resin. The molding variables included pressure, temperature, and time during both precuring and curing operations. The laminates were tested for several physical properties including resin content, percentage of voids, specific gravity, and flexural strength on the diagonal, both wet and dry.

"A porous wall was used in an attempt to eliminate reflections of oblique waves from a tunnel wall. Calculations were made of the required resistance characteristics of a wall in order that the flow through the wall, due to the pressure difference across a shock wave, would equal the component normal to the wall of the flow behind the shock wave. The resistance characteristic of a sintered bronze wall was measured and the reflections of waves impinging on the wall were observed at a Mach number of 1.62" (p. 1).

"A program of creep-rupture tests of several bars of Beryllium has been completed. The tests were made at 1200, 1400, 1550, and 1700 F. in protective atmospheres of tank helium or hydrogen. The results are given in a summary table and by creep and design curves. A description of the test set-up is included."

Report presenting a wind-tunnel investigation of an external store of fineness ratio 8.6 on the chord plane of several low-aspect-ratio wings. Testing occurred at a Mach number of 1.9 on wings with 60 degree leading-edge sweepback and unswept trailing edges with taper ratios of 0 and 0.28 and on an unswept wing with a taper ratio of 0.625. Results regarding the loading breakdown, store position, and effect of store on control characteristics are provided.

From introduction: "It has become desirable to develop an alternative method for the determination of lithium to serve as a stand-by method at times when the flame photometer is inoperative, or to supplement the latter in cases where a doubtful analysis requires further investigation. A method based upon the precipitation of lithium with potassium ferriperiodate was investigated because of its expected freedom from interference by aluminum."

Report presenting a wind-tunnel investigation to determine the effects of a section modification on the aerodynamic characteristics of a wing with 35 degrees of sweepback. The wing was modified by increasing the leading-edge radius of the NACA 64A010 section and adding a small amount of camber to the forward portion of the chord. Lift, drag, pitching-moment, and trailing-edge-flap hinge-moment characteristics of the modified wing are compared with results from the original wing.

This report has two parts to it discussing mineralogical examination of pitchblende concentrates and nitric acid digest residues. Part I gives the results of a cursory examination with the petrographic microscope of samples of pitchblende concentrates and residues to see if there is a relationship between the mineral composition of the samples and the filterability of the residue. Part II gives a revaluation of the data in Report BMI-241 on the mineral composition of two residues from the nitric acid digestion of pitchblende concentrates at the Rallinckrodt Chemical Works.

Heat-transfer investigation conducted on cooled as well heated impulse-type turbine blades in a static cascade to determine the effect of direction of heat flow on convective heat-transfer coefficients.

Memorandum presenting an investigation to determine the effect of mass distribution on the dynamic lateral stability and control characteristics of a model with a 60 degree triangular wing in the free-flight tunnel. Flight tests and calculations were made for five different loading conditions. Results regarding the oscillatory stability, lateral control, and general flight behavior are provided.

Report presenting the rates of flame propagation of four alkylsilanes as determined by the tube method. Results regarding alkylsilane flame velocities, blends of diethylsilane and n-pentane, and flame propagation theories are provided.

"An investigation to determine the structural damping characteristics of a full-scale airplane wing was conducted by the shock-excitation method wherein the wing was loaded to a predetermined deflection and the load suddenly released. The test specimen vibrated at its fundamental bending frequency of 1.69 cycles per second. Only the first 2 or 3 cycles showed any indication of a higher frequency being superimposed upon the fundamental bending frequency" (p. 1).

Report presenting the drag-reducing effectiveness of bleeding air to the base region of blunt-base bodies in a supersonic stream was investigated at a Mach number of 1.91.