From purpose and scope: Diamond drill exploration of the Lukachukai district was undertaken to find minable bodies of uranium ore and to determine whether sufficient reserves were present to warrant construction of a local mill. A minimum of 30,000 feet and a maximum of 50,000 feet of drilling were assigned to block out ore in the discovery area, Mesa I (pl. 1.). It was anticipated that some of the footage might be used to test Mesa II should the area become accessible. With access to Mesas II and IV subsequently provided by roads constructed by F. A. Sitton, Inc., and access to Mesa III furnished by a road constructed by the Atomic Energy Commission, the area available for drilling was eventually increased by some three and a half times. With no increase in allotted footage, the hole density was correspondingly decreased,

"A cascade impactor, an instrument for obtaining the size distribution of droplets borne in a low-velocity air stream, was adapted for flight cloud droplet-size studies. The air containing the droplets was slowed down from flight speed by a diffuser to the inlet-air velocity of the impactor" (p. 1).

From Summary: "Research was conducted to determine the effect of the electrode parameters of spacing, configuration, and material' on the energy required for ignition of a flowing propane-air mixture. In addition, the data were used to indicate the energy distribution along the spark length and to confirm previous observations concerning the effect of spark duration on ignition energy requirements. The data were obtained with a mixture at a fuel-air ratio of 0.0835 (by weight), a pressure of 3 inches of mercury absolute, a temperature of 80 F, and a mixture velocity of 5 feet per second."

The effects of water injection on a compressor are presented. To determine the effects of varying water-air ratio, the compressor was operated at a constant equivalent impeller speed over a range of water-air ratios and weight flows. Operation over a range of weight flows at one water-air ratio and two inlet air temperatures was carried out to obtain an indication of the effects of varying inlet air temperature. Beyond a water-air ratio of 0.03 there was no increase in maximum air-weight flow, a negligible rise in peak total-pressure ratio, and a decrease in peak adiabatic efficiency. An increase in inlet air temperature resulted in an increase in the magnitude of evaporation. An analysis of data indicated that the magnitude of evaporation within the compressor impeller was small.

Fundamental flame velocities are reported for pentane air, ethylene-air, and propylene-air mixtures for the concentration range 60 to 130 percent of stoichiometric. A form of the Tanford and Pease equation, which includes a small constant velocity term independent of diffusion, will predict the observed changes in flame velocity.

The results of an experimental investigation of the load distribution over two triangular wings in sideslip at Mach numbers from 1.20 to 1.79 are presented and compared with theory. The two wings tested have identical plan form, 45 degrees sweepback of the leading edge, and an aspect ratio of 4.0. One model was composed of round-nose airfoil sections and the other of sharp-nose, biconvex sections. For both wings the maximum thickness of streamwise sections was 6 percent and was located at the 30-percent chord.

Memorandum presenting an NACA submerged inlet and an NACA series I nose inlet installed in bodies of 12.4 fineness ratio to determine the drag and pressure-recovery characteristics of each body-inlet configuration. The tests were conducted with large-scale free-fall models released at an altitude of 40,000 feet, for mass-flow ratios of about 0.4 and 0.7 over a Mach number range of about 0.70 to 1.10. Results regarding drag and ram-recovery ratios are provided.

Report presenting the effectiveness of a 50-percent-semispan, constant-percent-chord elevon, and of upper-space spoilers as lateral control surfaces for a wing-fuselage combination with a wing swept back 63 degrees over a range of Mach numbers. For the elevon, results indicated that only about half of the predicted rolling-moment effectiveness was realized. The spoilers were found to be inferior to the elevons for lateral control because of a rapid loss of effectivness above an angle of attack of 4 degrees.

Report presenting an investigation in the high speed 7- by 10-foot tunnel to determine the effects of a spanwise variation in thickness ratio on the aerodynamic characteristics of a wing with a plan form identical to that of a constant-percent thickness-ratio wing program. The wing with thickness variation had 35 degrees of sweepback, aspect ratio 4, and taper ratio of 0.60 with airfoil section tapered from an NACA 65A006 section at the root chord to an NACA 65A002 section at the tip chord. Results regarding the lift characteristics, drag characteristics, and pitching-moment characteristics are provided.

Effects of humidity during fabric conditioning and during fabrication upon some physical properties of laminates prepared with glass fabric and an unsaturated polyester resin were investigated. Tests on these laminates included the measurement of flexural strength on the diagonal, both dry and after 7 days' immersion in water, specific gravity, resin content, percentage of voids, and total light transmission. Some data were also taken on lengthwise flexural strength.

Memorandum presenting a preliminary investigation of flame-stability and flame-extinction characteristics of a propane-air mixture in an annular combustion chamber conducted with both straight and rotational flow. The rotating mixture burned at higher axial-inlet stream velocities and with more stable flames than could be obtained with straight-flow burning.

Report presenting a large wind tunnel that has been converted to transonic operation by means of slots in the boundary extending in the direction of flow. The usefulness of a slotted wind tunnel has been augmented by devising a slot shape with which a supersonic test region with excellent flow quality can be produced.

An air-cooled turbine blade with a capped leading edge was investigated in a modified commercial turbojet engine over a range of engine speed from 4000 to 11,350 rpm. The cooling performance of the caped-leading-edge configuration was superior to all leading-edge cooling modifications previously investigated.

The paper presents flight measurements of the dynamic lateral stability of the D-558-II (BuAero No. 37974) research airplane. Data are presented for a range of calibrated airspeed from 167 miles per hour to 474 miles per hour.

Memorandum presenting several new methods that have been designed for obtaining electrical connection to thermocouples that are revolving at high speeds. Two general types of pickup system are described with modifications for special installations. Both pickup systems have been proved to transmit an accurate signal from a revolving thermocouple to within 0.045 millivolt at contact sliding speeds up to 5400 feet per minute.

Report discussing progress in research and development by the Health Instrument Divisions, Hanford Works, for the term from January through March, 1951.

The following report discusses neutron sources in reactors, discussing general conditions of the study using a flux reactor.

From Abstract: "The report is concerned with a theoretical analysis of the experiment known as the Calibration of the 3" Cross Control Rod. The experiment provided 29 points on a curve of reactivity (in hours per centimeter) versus depth of control rod insertion. An attempt to reproduce this curve theoretically has been quite successful."

"The purpose of this report is to present a method for the solution by IBM machines of the non-linear equations which attempt to predict the kinetic behavior of the liquid-fuel Aircraft Reactor Experiment."

Geological investigations report of the North Wash Mining distinct of the Henry Mountains in Utah.

This investigation was made to determine whether a diamond drilling program is warranted in the search for ore, and to provide basic data to guide such drilling.

"An investigation of a 1/24- scale dynamically similar model of the Douglas C-124 airplane was made to determine the ditching characteristics and proper technique for ditching the airplane. Various conditions of damage, landing attitude, flap setting, and speed were investigated. The behavior of the model was determined from visual observations, motion- picture records, and time-history deceleration records. The results of the investigation are presented in table form, photographs, and curves" (p. 1).

Technical report covering the Homogeneous Reactor Experiment (HRE) reactor physics and engineering, out-of-pile corrosion, in-pile studies, recombination of hydrogen and oxygen, HRE chemical studies, experimental programs for the HRE, and long-range studies. [From Summary]