This is the summary report on the ARF Project C 127, entitled "Preliminary Studies Related to Radioactive Fallout", covering the period from April 1, 1959, to April 29, 1960.

Abstract: Tests were made on 24 simply supported, post-tensioned, end-anchored, prestressed concrete beams with and without web reinforcement.

"An experiment to determine the effect of reactor irradiation on the thermal conductivity of uranium-impregnated graphite at elevated temperatures as described. The results show a decrease in the thermal conductivity saturating at [approximately] 60 percent at a temperature of 700 degrees C; at [approximately] 50 percent at a temperature of 1000 degrees C; and at [approximately] 25 percent at a temperature of 1300 degrees C. It was found that after irradiation at a given temperature, exposure at a higher temperature resulted in an increase in the thermal conductivity. The converse was also observed. Within the precision of measurement there was no difference in effed between temperature changes produced by varying the fission rate in the samples and changes produced by varying the power in an external heater."

The apparatus and procedures that are to be used to fill the liquid metal system of the Pratt and Whitney Forced Convection Liquid Metal Inpile Loop are described. The liquid metal to be used is a mixture containing 56% Na and 44% K, which is a liquid at room temperature. In order to simplify the filling procedure at the reactor site, two containers, each of which contains exactly enough liquid metal to fill the experiment to the prescribed level, a fill dolly incorporating a purified helium system, and an evacuation system will be provided at the reactor site. After completion of the liquid metal transfer, the liquid metal fill tube will be crimped, cut, and seal welded. The liquid metal and helium systems will then be pressurized through the helium fill tubes, which will also be crimped, cut, and seal welded. Each tube seal weld will be inspected after completion of the weld by mass spectrometry leak check and dye penetrant fault detection

Report presenting an investigation of a wing swept back 35 degrees in combination with one basic body and three modified bodies at a range of Mach numbers from 0.60 to 1.20. Results regarding force studies and pressure studies are provided. The bodies modified according to the Kuchenmann ring-vortex method resulted in superior aerodynamic characteristics except with regard to zero-lift drag at high supersonic Mach numbers.

"The perturbation field induced by a line vortex in a supersonic stream and the downwash behind a supersonic lifting surface are examined to establish approximate methods for determining the downwash behind supersonic wings. Lifting-lines methods are presented for calculating supersonic downwash. A bent lifting-line method is proposed for computing the downwash field behind swept wings. When applied to triangular wings with subsonic leading edges, this method gives results that, in general, are in good agreement with the exact linearized solution" (p. 635).

Report presenting a flight investigation using a rocket-powered model to evaluate the roll-rate stabilization of the Naval Ordnance Test Station SIDEWINDER missile, which uses aerodynamic damping by gyro-actuated rollerons. Dynamic roll instability was found to occur in flight.

Report presenting a study of the effect of fuel properties on carbon deposition in jet-propulsion engine combustors using seven fuels: kerosene, Diesel fuel oil, toluene, xylene, 62-octane gasoline, a commercial solvent, and AN-F-32 (JP-1) in an I-16 engine at static sea-level conditions and constant rotor speed. Results regarding the reproducibility of data, reduced exhaust-jet-nozzle area, and fuel comparison are provided.

Memorandum presenting an investigation of the effect of fuel composition and boiling point on the performance of the type of I-16 jet-propulsion engine. Testing occurred with 14 fuels embodying different types of hydrocarbon and with a range of boiling points. The results indicated that fuel composition and boiling range have a negligible effect on engine thrust, rotor speed, and gas temperatures for the principal types of hydrocarbon fuel when used for short periods of time.

Report presenting an investigation of liquid-film cooling at a variety of air temperatures and Reynolds numbers. Results regarding the effect of coolant flow per circumferential length on liquid-cooled length, correlation of heat transfer from hot gas to liquid film for constant coolant flow per circumferential length, and generalized plot of film-cooling data based on heat-transfer correlation at constant coolant flow per circumferential length are provided.

The structural damping in the torsion mode of vibration of a series of untwisted, laminated thin beams simulating propeller blades is presented. The number of lamination were varied, as well as the bonding material and the method of joining lamination. Application of the data to the calculation of the minimum flutter speed of thin propeller blades indicates that appreciable gains in the minimum flutter speed may be obtained for laminated blades using a Cycleweld bond.

Report presenting an investigation of the zero-lift-drag characteristics of nine symmetrical airfoils at a range of Mach and Reynolds numbers. Results regarding pressure and force data are also provided.

The results of an investigation of the effects of leading-edge chord-extensions and extensible leading-edge flaps on the low-speed aileron characteristics of a 52 degrees sweptback wing with circular-arc airfoil sections are presented. A description and illustrations of the vortex flow as it passes over the wing are included. The investigation was conducted at Reynolds numbers of 5.5 times 10(exp 6) and 1.3 times 10(exp 6) and corresponding Mach numbers of 0.11 and 0.065 for an angle-of-attack range of 0 degrees through stall.

Memorandum presenting a theoretical study of the effect of limiting the deflection and rate of deflection of the control surface on the normal acceleration and roll response to step commands for a representative, automatically controlled, supersonic, tailless interceptor. Results regarding pitch, roll, and some general comments are provided.

Report presenting an experimental investigation to determine the effect of rotor leading-edge sweepback on the aerodynamic performance of a transonic turbine. Using an unmodified stator with the modified rotor resulted in large incidence angles at the rotor mean and tip sections.

Report discussing an investigation of the supersonic area rule using rocket-propelled zero-lift models of straight wing-body configurations at a range of Mach and Reynolds numbers. The body was modified with symmetrical indentations according to area-rule considerations in order to reduce wave drag. The indentations were found to have an effect at Mach numbers 1.10 and 1.41 but did not have any benefit above Mach number 1.3.

Memorandum presenting an investigation to determine the static longitudinal and lateral stability and control characteristics of an airplane configuration with a trapezoidal wing with modified hexagonal airfoil section and tail surfaces with 5 degrees semiangle wedge sections carried out in the 11-inch hypersonic tunnel.

Abstract: The silicides of Ti, Zr, Ce and Nb were investigated to determine the phases present at temperatures around 2000 K. The reactions of silicides of Ti, Zr, Ce, Nb, Ta, Mo, and W with carbon were studied at these temperatures. Also a limited amount of work was done on the reactions of some of the silicides with nitrogen. The data have been used to establish ternary phase diagrams for the systems and to obtain upper and lower limits for the heats of formation of the silicides.

Abstract. An inexpensive method for detection of dust-loaded high efficiency filters is described. Air flow is continuously indicated by elementary pitot tubes and plastic rotameters. Accuracy obtained is within +- 15%. Information as to construction, installation, and use is presented.

Report discussing the refractory properties of pure uranium dioxide, as well as methods for forming the compound. Health hazards of uranium dioxide are briefly mentioned.

Abstract: "A summary of the information contained in several reports relative to the use of hexachloropropylene for the preparation of UCl4. Data relative to the performance of charge material so prepared and to pilot plants are omitted."

A report regarding many uranium production plants constructed during the existing emergencies and pressures of World War II that were not intended to be permanent instillations. These plants either contractor or government owned, with buildings on the most part belonging to the contactor and a major portion of the processing equipment belonging to the government, became outmoded with the development

The purpose of this work was to produce a reliable, inexpensive instrument for the detection of hard beta contamination on the clothing of personnel. Also, the monitoring was required to be accomplished without interrupting the normal activities of the employees.

From Summary: "The major objective of the run was the investigation of fuel stability. The reactor operated for long periods at the design power of 5 Mw with none of the usual indications of instability while the system pressure was kept at 1250 psig. Run 21 ended on January 22, so that the reason for an abrupt change in the mixing rate of fuel between the core and blanket could be investigated and a reactor steam-system valve could be repaired."