A collection of quantity recipes for school lunches using nonfat dry milk. Includes general directions for handling dried milk during the preparation stages.

Memorandum presenting a preliminary investigation made in the two-dimensional low-turbulence tunnel on an NACA 64A010 airfoil with permeable surfaces to obtain an indication of the stabilizing effect of area suction on the laminar boundary layer. Although the airfoil surface had many waves and irregularities of contour, the data corroborated qualitatively the theoretically predicted stabilizing effect of area suction on a smooth flat plate.

Report discusses several experiments regarding boundary layers and their influence on aircraft. The first experiment investigates how to best design airfoils. The second involves using suction to remove the boundary layer. The third involves surface disturbances and how they may affect the boundary layer.

From Summary: "On the basis of modern plasticity considerations, a unified theory of plastic buckling applicable to both columns and plates has been developed. For uniform compression, the theory shows that long columns which bend without appreciable twisting require the tangent modulus and that long flanges which twist without appreciable bending require the secant modulus. Structures that both bend and twist when they buckle require a modulus which is a combination of the secant modulus and the tangent modulus."

"Charts are presented for the analysis of the stability under longitudinal compression of simply supported rectangular plates with several equally spaced transverse stiffeners that have both torsional and flexural rigidity" (p. 1).

Note presenting a solution for the motion of a prismatic float of infinite length that is dropped vertically into the water at zero trim. A lift force, simulating seaplane wing lift, is assumed to act on the float and to remain constant during the impact period.

"Methods are presented for constructing charts suitable for adjusting to standard values plate test results for the critical compressive stress and the average stress at maximum load. The methods take into account the difference between the compressive properties of the material used for the tests and those upon which the design is to be based. Illustrative charts are included for extruded 24S-T and 75S-T aluminum alloys" (p. 1).

"As basic information for the design of thin-web spars, the theoretical shear buckling stress is presented for an infinitely long, clamped plate divided into square panels by rigid intermediate supports. In addition, results are given for the shear buckling stress of a plate of infinite length and width having intermediate rigid supports that form an array of square panels. The results indicate the fallacy of the usually made assumption that each panel buckles in shear as if it were simply supported along the intermediate supports" (p. 1).

The expressions for the damping derivatives in pitch and roll of triangular wings are derived by means of the linearized theory. In the method used, the wing is represented by an unknown distribution of doublets. An integral equation containing the unknown distribution is set up and solved by analogy with known incompressible flow relations. It is pointed out that the results may be used to obtain damping coefficients of a limited series of sweptback wings, the most interesting of which are the so-called "arrow wings.".

Report presenting analytical considerations of the energy transformations in convective-type clouds indicate that a simple function of the height of convective activity and horizontal-temperature variations could yield a measure of the gustiness in clouds. A simplified relation that may be used to forecast the maximum effective gust velocities within convective-type clouds is developed. The analysis indicates that the method might be extended to almost all cloud types.

Report presenting an investigation of the hydrodynamic qualities of a hypothetical flying boat with a hull with a length-beam ratio of 15 in tank no. 1. The flying boat had a design gross weight of 75,000 pounds, a gross load coefficient of 5.88, a wing loading of 41.1 pounds per square foot, and a power loading of 11.5 pounds per brake horsepower for take-off. Results regarding the longitudinal stability, spray characteristics, take-off performance, and summary chart are provided.

Report presenting an investigation to determine the boundary-layer characteristics of an NACA 0009 airfoil equipped with 0.25- and 0.50-airfoil chord plain sealed flaps. The test objective was to define as thoroughly as possible the characteristics of two of the configurations used in a comprehensive investigation of control-surface characteristics and to provide additional data for comparison with previous boundary-layer analyses.

Report presenting an investigation of the effects of altitude on the heat dissipation and on the oil pressure drop of an unjacketed and a conventional jacketed aircraft oil cooler at up to 40,000 feet. The investigation covered a variety of oil flows, cooling air flows, and oil-inlet temperatures.

Note presenting a small-deflection theory developed for the elastic behavior of orthotropic flat plates in which deflections due to shear are taken into account. The theory covers all types of flat sandwich construction and includes seven physical constants for each plate, of which six are independent.

Report presenting an examination of the conditions for similarity of flow for a compressible fluid with heat transfer with particular reference to variation of stagnation temperature and scale of the model. Important simplification of the experimental procedure for tests simulating flight at high Mach number is possible by using the similarity relations developed in the report.

Report presenting an investigation to identify the roles of solid-surface films in the mechanisms of sliding and lubrication involved in the mating and compatibility of boundary-lubricated slider surfaces, in the action of extreme-pressure lubricants, and in the operation of slider surfaces not supplied with fluid lubricants. Results regarding the films formed during run-in, films formed by extreme-pressure lubricants, and supplemental or dry-lubrication films are provided.

Report presenting an investigation to determine optimum double-slotted-flap configurations for seven thin NACA airfoil sections. Lift characteristics, pitching moment, and optimum positioning are explored.

Note presenting Von Kármán's equations for thin plates with large deflections are solved for the special cases of rectangular plates with ratios of length to width of 1.5 and 2 and loaded by uniform normal pressure. The boundary conditions are such to approximate panels with riveted edges under normal pressure greater than that of the surrounding panels.

Note presenting tests to evaluate the effects of various surface conditions, certain defects, and repair of some of the defects by welding on the fatigue strength of an aluminum sand-cast alloy. The surfaces studied included as-cast, machined, grit-blasted, and shot-blasted surfaces. Results regarding fatigue and tensile tests are provided.

"A series of tests were made for the purposes of establishing the effects of several variables in welding technique on the fatigue strength of arc-welded joints in SAE 4130 seamless steel tubing. The variables included type of electrode, speed of welding, current, position, amount of preheat, and other factors which in turn controlled the weld contour, penetration, and depth of the heat-affected zone. A range of joint design was also investigated" (p. 1).

Report presenting a collection of available test data on lateral control with full-span flaps. Internal-control effectiveness and hinge-moment data were obtained from two-dimensional, three-dimensional, and flight tests. Results regarding slot-lip and flap-trailing-edge ailerons, spoiler-type ailerons other than slot-lip ailerons, ailerons with retractable-type flaps, and application of data to specific airplane design are provided.

Combustion chamber liners for gas turbines and experimental set-ups were tested for failure. A ceramic-lined test chamber was operated at fuel/air ratios up to 0.050. Thermal-shock evaluation indicated that a ceramic lining, which expands after firing, would crack but would not fall apart during operation. Refractoriness of the lining and the resistance to mechanical shock were adequate. In general, shell temperature reductions of approximately 400 deg F were effected by the use of this lining at fuel/air ratios of 0.016 and 0.050. The mechanism of failure of the ceramic lining was induced by sudden heating and cooling during operation.

Report presenting information about some of the fundamental concepts and lines of development that may be undertaken regarding helicopter stability. Some of the principles discussed include method of control, control lag, stability characteristics, control forces, and center of gravity. Some of the means for improvement discussed include use of a horizontal stabilizer, use of trim devices, use of power-operated controls, automatic controls, and choice and grouping of indicating instruments.

Report presenting an investigation of a one-eighth segment of an annular combustor suitable for use as a component of an experimental turbojet engine. Due to the small space available for the combustor, a special design involving a minimum of obstructions in the combustion chamber was created. Results regarding the temperature-rise efficiency, total-pressure loss, and exhaust-gas temperature variation for several simulated engine operating conditions are provided.