The B Pile operated 25 MW below rated power level without interruption during the week. The D Pile was shut down on January 29. During the shutdown 103 tubes were discharged. The shut down lasted for 15 hours. During operation after the shut down power was reduced to meet graphite temperature restrictions. The F Pile was run steadily throughout the week at 25 MW below rated level. Iron content in the process water averaged 0.015, 0.011 and 0.010 ppm at B, D, and F Areas, respectively. Examination of the slugs discharged from four corrosion tubes at F has been completed. A summary of conditions found in the vertical and horizontal aluminium thimbles at D and F during a recent inspection are given. Results are given on the graphite expansion problem.

From Summary: "Qualitative investigations have shown that use of the NACA injection impeller with the R-3350 engine increases the inertia of the fuel-injection system and, when the standard fuel-metering system is used, this increase in inertia results in poor engine acceleration characteristics. This investigation was therefore undertaken to determine whether satisfactory acceleration characteristics of the engine equipped with the injection impeller could be obtained by simple modifications to the fuel-monitoring system. The engine was operated with two types of carburetor; namely, a hydraulic-metering carburetor incorporating a vacuum-operated accelerating pump and a direct-metering carburetor having a throttle-actuated accelerating pump."

A training manual designed to teach aerial photography for military purposes.

"The XF-12 airplane was designed by Republic Aviation Corporation to provide the Army Air Forces with a high performance, photo reconnaissance aircraft. A series of air-stream surveys were made n the vicinity of the empennage of a 1/8.33-scale powered model of the XF-12 airplane in the Langley 19-foot pressure tunnel. Surveys of the vortical-tail region were made through a range of yaw angles of plus or minus 20 degrees at a high and low angle of attack" (p. 1).

From Summary: "An investigation of turbojet-engine thrust augmentation by means of tail-pipe burning has been conducted in the NACA Lewis altitude wind tunnel. Several fuel systems and flame holders were investigated in a 29-inch-diameter tail-pipe burner to determine the effect of fuel distribution and flame-holder design on tail-pipe-burner performance and operational characteristics over a range of simulated flight conditions. At an altitude of 5000 feet, the type of flame holder used had only a slight effect on the combustion efficiency."

"An investigation was conducted with a single combustor from a British Rolls-Royce Nene turbojet engine to determine the altitude performance characteristics of AN-F-58 fuels. Three fuel blends conforming to AN-F-58 specifications were prepared in order to determine the influence of fuel boiling temperatures and aromatic content on combustion efficiencies and altitude operational limits. The performance of the three AN-F-58 fuels was compared in the range of altitudes from sea level to 65,000 feet, engine speeds from 40- to 100- percent normal rated, and flight Mach numbers of 0.0 and 0.6" (p. 1).

Report discussing three fuels conforming to AN-F-58 specification were investigated in order to determine the influence of boiling temperatures and aromatic content on altitude performance in single combustor of a 4600-pound-thrust turbojet engine.

From Introduction: "An analysis of eddy currents in a compressor blade, the geometry of which has been limited to that of a flat plate for simplicity, is presented."

Abstract: A TEC regulator amplifier driving an Eaterline-Angus recording meter was used to record magnet current variations. Tests were made to determine magnet current variations. Tests were made to determine magnet current stability for currents from 500 amperes to 4000 amperes. Changes were necessary in both the TEC and GE regulators before currents below 2500 amperes could be regulated. Regulation to 0.025 percent for and hour was obtained for currents of 1000 to 4000 amperes with the TEC and GE regulators, and regulation to 0.05 percent for 500 ampere currents.

Report presenting comparative drag measurements at zero lift at transonic speeds for two sharp-leading-edge airfoils using the NACA wing-flow method. One airfoil had a symmetrical circular-arc section and one had a symmetrical double-wedge section. The primary difference in the drag characteristics of the two airfoils at zero lift is the earlier drag rise of the double-wedge section.

Report presenting the drag of a series of wing-body combinations by the free-fall method in order to provide information on the drag characteristics of promising transonic and supersonic airplane arrangements. Time histories, Mach number variations, and drag coefficients for several areas of the body are provided.

From abstract: "The deposit on the rods is in the form of a brittle uneven tube which is cracked off and subsequently pulverized to a 200-mesh powder. This report is chiefly concerned with methods of consolidating this powder and shaping it into forms required, though it also discusses to some extent other methods of shaping boron or born-rich materials."

An exact solution and a closely concurring approximate energy solution are given for the buckling of an infinitely long flat plate under combined shear and transverse direct stress with edges elastically restrained against rotation. It was found that an appreciable fraction of the critical stress in pure shear may be applied to the plate without any reduction in the transverse compressive stress necessary to produce buckling. An interaction formula in general use was shown to be decidedly conservative for the range in which it is supposed to apply.

A chart is presented for the values of the coefficient in the formula for the critical compressive stress at which buckling may be expected to occur in flat rectangular plates supported along all edges and, in addition, elastically restrained against rotation along the unloaded edges. The mathematical derivations of the formulas required in the construction of the chart are given.

Report presenting an investigation to determine the damping-in-roll characteristics of a 42.7 degree sweptback wing using a linearly twisted wing to represent a rolling wing. Results regarding the effect of the airfoil contour, damping-in-roll coefficient, wing-tip helix angle, and theoretical results are provided.

Report presents the results of an investigation made to find the effect of ground on the aerodynamic characteristics of a Franklin PS-2 glider. The lift, the drag, and the angle of attack of the glider in towed flight were determined at several heights from 0.14 to 1.19 span lengths and at various speeds for each height. Two wing arrangements were tested: the plain wing, and the wing with a nearly full-span 30-percent-chord split flap deflected 45 degrees. The experimental results for the plain wing were in good agreement with theoretical values calculated by the method of Wieselsberger for both the angle of attack and the drag coefficient at a height of 0.21 span length; Tani's refinements of the theory had a practically negligible effect on the computed values in this case.

The assay technique is discussed in detail. The results of three purity determinations are: 94.92 per cent, 100.50 per cent, and 106.9 per cent. The errors present in each determination are stated. The inherent dangers in the present procedure are pointed out, and an improved method is outlined.

From Summary: "An analysis of the nose-inlet shapes developed in previous investigations to represent the optimum from the standpoint of critical speed has shown that marked similarity exists between the nondimensional profiles of inlets which have widely different proportions and critical speeds. With the nondimensional similarity of such profiles established, the large differences in the critical speeds of these nose inlets must be a function of their proportions. An investigation was undertaken in the Langley 8-foot high-speed tunnel to establish the effects of nose-inlet proportions on critical Mach number to develop a rational method for the design of high-critical-speed nose inlets to meet desired requirements."

Report discussing the results of flight tests to determine the drag at zero lift of a swept-back wing of inverse taper using an NACA 65-009 airfoil. The data was compared to untapered wings with a similar degree of sweepback. The tapered wing was found to have a lower drag coefficient than the 34-degree swept-back untapered wing but a higher drag coefficient than the 45-degree swept-back untapered wing.

Abstract: Mice of different ages ranging from 1.5 to 12 months have been exposed to gamma rays in an effort to determine the change in radiosensitivity with age. The dose necessary to cause 50% killing was determined for each age group and sex. No change in sensitivity with age was observed with either sex, although the experimental error in the case of the males was quite large. The females were found to be more resistant than the males.

From Summary: "An analysis is presented of the effect of torsional flexibility on the rolling characteristics at supersonic speeds of tapered unswept wings with partial-span constant-percent-chord ailerons extending inboard from the wing tip. The geometric variables considered are aspect ratio, taper ratio, aileron span, and aileron chord. The shape of the wing-torsional-stiffness curve is assumed and the twisting moment is considered to result solely from the pressure distribution caused by aileron deflection, so that the necessity of using a successive-approximation method is avoided."

"Investigations in the Langley 20-foot free-spinning tunnel of models of five jettisonable nose sections have shown that the airplane nose sections are inherently unstable but can be stabilized by the addition of suitable fins. An empirical criterion has been developed which indicates the fin area required for stabilizing an airplane jettisonable nose section" (p. 1).

Report presenting an analysis of the estimated flying qualities of a tailless airplane with the wing quarter-chord line swept back 35 degrees in a range of Mach numbers based on tests of a model of the airplane in the 7- by 10-foot tunnel. Results regarding performance, longitudinal stability and control, and lateral stability and control are provided.

Memorandum presenting an analysis made of the probable range of the stability parameters of present and future missiles. Included is a short review of the dynamic theory and some of the factors and assumptions influencing the stability derivatives and equations of motion.