"Investigations were conducted in the Cleveland altitude wind tunnel to determine the performance and operational characteristics of the 19B-2, 19B-8, and 19XS-1 turbojet engines. One objective was to determine the effect of altitude, flight Mach number, and tail-pipe-nozzle area on the performance characteristics of the six-stage and ten-stage axial-flow compressors of the 19B-8 and 19XB-1 engines, respectively, The data were obtained over a range of simulated altitudes and flight Mach numbers" (p. 1).

The test of March 7, 1947 was planned as a check on power coefficient values; however, an analysis of reactivity data gave evidence of a considerable flattening of ``A`` rod in the region between 0--75 inches out. A second test of longer duration was therefore made on April 1, 1947 in order to obtain a check calibration of this portion of the control rod. The results of this test verified the flattening of this portion of ``A`` rod. The redetermined power coefficients based on new rod calibrations are given.

Report presenting the results of pressure-distribution tests to determine the effects of compressibility on the characteristics of the NACA 66,2-215, 66,2-015, 65(216)-418, 16-212, and 23015 airfoil sections. Schileren photographs of the air flow and data on the wake characteristics was also obtained.

Report presenting an investigation of aileron flutter associated with high-speed flight. When the aileron control system was modified by installing a hydraulic irreversible unit, it was possible to delay aileron flutter and reduce its amplitude. Results regarding the aileron flutter with and without the modifications, analysis of the time histories for the control systems, and relation between aileron upfloat and flutter are provided.

There were no cases of unusual blistering of slugs being followed under Production Tests. Two normal production tubes were borescoped following trouble with discharge. In Tube 3188-D a distorted slug became stuck in the region of sharp curvature near the inner end of the rear gun barrel; this is the first time this phenomenon has occurred. Examination of irradiated slugs of rolled metal after normal exposure indicates that rolled material has no particular advantages over extruded material from the standpoint of blistering. However, no extensively blistered pieces were found in either the rolled metal are being held for more extended exposure. Inspection of a large number of Van Stone flanges in the D and F Piles has confirmed that the inlet flanges are in generally good condition but that the rear Van Stone flanges of tubes in the 0.140-inch orifice sone of both piles were badly corroded and generally contained deep pits that extended about half-way through the flange. The Van Stone test units are to be installed unshielded in the risor room at the rear of the D Pile, since the shielding required in the X Sample Room exceeded the allowable floor loading. Recent experimental observations indicate that solid …

Flight tests were conducted at the Flight Test Station of the Pilotless Aircraft Research Division at Wallop Island, Va., to determine the longitudinal control and stability characteristics of 0.5-scale models of the Fairchild Lark pilotless aircraft with the tail in line with the wings a d with the horizontal wing flaps deflected 60 deg. The data were obtained by the use of a telemeter and by radar tracking.

Report presenting the results of an investigation conducted in the altitude wind tunnel to determine the performance of a 20-inch ramjet. The investigation was conducted at a range of altitudes and ram-pressure ratios using preheated 62-octane fuel. A net thrust of 8135 pounds educed to standard sea-level conditions, a net-thrust coefficient of 0.74, and an overall efficiency of 12.6 percent were attained at Mach number 1.845 at which the engine with a 5-foot combustion chamber was operated.

Report presenting testing of a full-scale, semispan, horizontal tail surface for a jet-propelled fighter airplane in the 16-foot high-speed tunnel to determine the variation of the chordwise and spanwise pressure distributions with Mach number. Surface irregularities were found to cause appreciable distortion of the pressure distribution. Results regarding chordwise distributions, spanwise distribution, effect of Mach number on root bending moment, and estimated critical Mach numbers are provided.

Report presenting the use of wall perforations on supersonic diffusers to avoid the internal contraction-ratio limitation. Experimental results on a preliminary model of a perforated diffuser at Mach number 1.85 are provided. A theoretical discussion of the flow coefficients and the size and spacing of the perforations are included.

Report presenting an investigation in the 300 mph 7- by 10-foot tunnel to determine what modifications could be made to conventional bomb bays to reduce the tumbling difficulties experienced with light-weight bombs. The investigation indicated that there is a definite region of reversed flow inside the bomb bay which must be weakened or destroyed if good drops are to be obtained.

This report discusses the contributions of the workers at Tennessee Eastman Corporation in the investigation of limiting conditions in the application of penta-ether (aka. dibutoxytetraethylene).

This report contains a letter, written on July 25, 1947, concerning the sampling program at Columbia River. The author suggests reducing the sampling schedule. He states that chemical composition sampling should be reduced by one-fifth and radioactivity sampling be reduced by one-third. He suggests that only mid-channel samples are required for representative studies. He further states that weekly sampling should occur. By following these suggestions, the cost of the sampling program should be drastically reduced because the hours of manpower taken to sample the river, analyze the data, organize, and store information would be reduced.

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Abstract: "The need often arises for determining the critical chemical concentration of uranium solution in the conical bottom of a plant reactor or storage vessel, or the dimension if the concentration is known. This report describes the mathematical analysis of Poisson's equation for a spherical sector, which approximates a right circular cone. The ratio of the critical dimension of an equivalent sphere to the height of the sector for various sector angles is derived from a comparison of first eigenvalues. No description of further relations between composition and dimensions is discussed in the report."

Stress-rupture data for four heat-resisting alloys are analyzed according to equations of the theory of rate processes. A method for determining the four parameters of structure and composition is demonstrated and the four parameters are determined for each of the alloys: forged S816, cast S816, cast S590, and cast Vitallium. It is concluded that parameters can be determined for an alloy provided sufficient reliable experimental data are available.

Investigations were conducted to determine effectiveness of refrigerants in increasing thrust of turbojet engines. Mixtures of water an alcohol were injected for a range of total flows up to 2.2 lb/sec. Kerosene was injected into inlets covering a range of injected flows up to approximately 30% of normal engine fuel flow. Injection of 2.0 lb/sec of water alone produced an increase in thrust of 35.8% of rate engine conditions and kerosene produced a negligible increase in thrust. Carbon dioxide increased thrust 23.5 percent.

A 1/5.5-size powered dynamic model of the Columbia XJL-1 amphibian was landed in Langley tank no. 1 in smooth water and in oncoming waves of heights from 2.1 feet to 6.4 feet (full-size) and lengths from 50 feet to 264 feet (full-size). The motions and the vertical accelerations of the model were continuously recorded. The greatest vertical acceleration measured during the smooth-water landings was 3.1g.

From Introduction: "This report presents an analysis based on flight and wind-tunnel test data directed toward the determination of the probable cause of the pitch-up. Wing pressure distribution and stability and control characteristics in the dive are also included."

Report presenting calculations based on a theoretical analysis for a composite engine consisting of a uniflow two-stroke-cycle spark-ignition engine, a compressor, a blowdown turbine, and a steady-flow turbine. Operation of the engine is considered for four cases of gas mixtures and steady-flow turbine temperatures.