A report which covers progress on the testing of the General Engineering and Consulting Laboratory Turbine Pump No. 1 from June 16, 1948, to July 31, 1948.

This report analyzes Parian and Teflon that were exposed to solutions of 1AX, 1AS, and 1AF, ANL June 1, 1948 Flowsheet, under conditions described in the following report.

Technical report describing a gasometrical method for the determination of H2 in extruded U rods.

Report discussing experiments on the photometric determination of various elements in the presence of trace amounts of Uranium.

Final report describing the development and usage of an automatic decade scaler which operates for a fixed number of counts, developed for use with a Geiger tube.

Report discussing the mutual interference effects of tail surfaces and a stern propeller on a model of the XB-42.The main focus was to determine the effect of tail surface-propeller spacing upon the periodic tail surface loading coincident with propeller blade passage.

From Summary: "Directly comparable drag measurements have been made of an airfoil with a conventional rectangular plan form and an airfoil with a sweptback plan form mounted on freely falling bodies. Both airfoils had NACA 65-009 sections and were identical in span, frontal area, and chord perpendicular to the leading edge. The sweptback plan form incorporated a sweepback angle of 45 degrees. The data obtained have been used to establish the relation between the airfoil drag coefficients and the free-stream Mach number over a range of Mach numbers from 0.90 to 1.27. The results of the measurements indicate that the drag of the sweptback plan form is less than 0.3 that of the rectangular plan form at a Mach number of 1.00 and is less than 0.4 that at a Mach number of 1.20."

A lightweight instrument that utilizes resistance-wire electric strain gases to measure propeller-shaft thrust has been developed. A wind-tunnel investigation on a propeller installed, on a single-engine pursuit airplane showed that the instrument gave a reliable indication of propeller-shaft thrust to an accuracy of +/-2 percent within its calibrated range. No attempt was made to determine the relation of indicated shaft thrust to net propeller thrust.

Memorandum presenting an investigation at the tank no. 2 monorail of the landing on smooth water of a scale model of a hypothetical jet- and rocket-propelled airplane designed to fly at transonic speeds. The test is part of an investigation of the feasibility of the operation from water of high-speed airplanes. The results of the test form a basis for evaluating the improvement in hydrodynamic characteristics.

"About 500 additional references pertaining to hydrodynamic design of seaplanes have been compiled, and the information is presented in the form of abstracts classified under six main headings:GENERAL INFORMATION, HYDROSTATICS, HYDRODYNAMICS, AERODYNAMICS, OPERATION, and RESEARCH. The compilation is an extension of NACA RM No. L6I13, entitled "Abstracts Pertaining to Seaplanes," by Jerold M. Bidwell and Douglas A. King. An author index and a subject index are included" (p. 1).

Report presenting outdoor static testing made on two high-solidity propellers of different design, one shrouded and the other unshrouded. Three shrouds were tested to determine the effects of shroud length and exit area. Results regarding the action of shroud, results and comparison of propellers, and comparison with theory are provided.

From Summary: "The results of numerous unrelated tests of dive-recovery flaps are collected in this report and presented in a form suitable for use in the preliminary design of dive-recovery flap installations. Since the data were obtained for airplane models of quite widely varying configurations, and are limited largely to a Mach number of 0.80, it is recommended that each new installation be carefully flight-tested before final approval. A flight-test procedure is outlined which will insure a maximum degree of safety."

Report presenting an investigation at the tank no. 2 monorail of the landing on smooth water of a dynamic model of a hypothetical jet- and rocket-propelled airplane designed to fly at transonic speeds. The model skipped out of the water and experienced maximum normal accelerations up to 7.4g and maximum longitudinal accelerations up to 4.5g. Results of landing the basic model and landing the modified model that has a slightly different fuselage are provided.

"Flight tests were conducted on a R-2800-21 engine in the P-47G airplane to determine the effect on the wall temperatures of cylinder 10 of throttling the charge in the intake pipe and of injecting a water-ethanol coolant into the intake pipe. Cylinder 10 was chosen for this investigation because it runs abnormally hot (head temperatures of the order of 45 F higher than those of the next hottest cylinder) at the medium and high-power conditions. Tests with interchanged cylinders showed that the excessive temperatures of cylinder 10 were inherent in the cylinder location and were not due to the mechanical condition of the cylinder assembly" (p. 1).

"An analysis is presented of the influence of wing aspect ratio and tail location on the effects of compressibility upon static longitudinal stability. The investigation showed that the use of reduced wing aspect ratios or short tail lengths leads to serious reductions in high-speed stability and the possibility of high-speed instability" (p. 1).

Report presenting an investigation of a basic wing-fuselage combination with several types of external-store installations meant to delay the advent of airplane buffet caused by external stores. Modifications for airplane design in order to minimize the effect of drag are provided. Some of the arrangements tested included the tandem-mounted arrangement, flush-mounted arrangement, store with a fan-shaped tail, and auxiliary airfoil arrangement.

Report discussing flight tests of airplane-like models to determine the effect of airfoil section profile and thickness ratio on the zero-lift drag of low-aspect-ratio wings at supersonic speeds. Five rectangular wings with the same aspect ratio and a variety of airfoil thicknesses were tested to determine the effect of thickness ratio.

Memorandum presenting low-speed wind-tunnel tests made of flat-plate wings with an aspect ratio of 2.0 and their leading edges swept back 63.4 degrees. Both plain and split flaps of several plan forms were investigated to provide qualitative information as to the relative merits of these flaps. The constant-chord flap was found to be the most effective and a skewed wing-tip flap the least effective.

Report presenting a partial-span wing tested to determine the cause of a flutter which had occurred in high-speed flight. Changes were made to the wing stiffness, location of the center of gravity of the wing, and the mass balance of the aileron. Results regarding the effect of wing changes on flutter, effect of aileron changes on flutter, shock-wave study, and static aerodynamic coefficients are provided.

Memorandum describing preliminary investigations of two 3-inch-diameter slotted test sections over a range of pressure ratios from 1.3 to 10.0. The two test sections varied based on the number of slots and amount of open space, but they showed no appreciable difference in performance. Results regarding the slots with no chamber around the test section and with a closed chamber around the test section are provided.

Report presenting an investigation to determine the spin and recovery characteristics of a model of the Douglas AD-2W airplane, which has a large radome installation. Results indicated that the plane has satisfactory erect and inverted spin-recovery characteristics. Information about erect spins, inverted spins, and recommended recovery technique is provided.

Report presenting aerodynamic and icing investigations on a model of a turbojet-engine nacelle in order to provide icing protection for the engine, protective screen, and accessory housing by the introduction of hot gases into the inlet-air stream. Adequate ice protection was afforded when the minimum kinetic temperature in the protective screen was greater than 32 degrees Fahrenheit.

Report presenting the lift and pitching-moment characteristics of two wings of the same plan form measured over a range of Mach and Reynolds numbers using the wing-flow method. One wing had a symmetrical airfoil section and no twist, while the other was cambered and twisted to support a uniform load distribution at a lift coefficient of 0.25 at Mach number 1.5. A comparison with previous testing is also provided.

Report discussing an investigation of the aerodynamic characteristics of an airfoil-forebody swept flying boat hull with a wing and tail swept back 51.3 degrees at the leading edge. The swept hull's minimum drag coefficient was about the same as the parent model or streamline model. Various combinations of flaps were also utilized.