"Convenient charts are presented for computing the thrust, fuel consumption, and other performance values of a turbojet system. These charts take into account the effects of ram pressure, compressor pressure ratio, ratio of combustion-chamber-outlet temperature to atmospheric temperature, compressor efficiency, turbine efficiency, combustion efficiency, discharge-nozzle coefficient, losses in total pressure in the inlet to the jet-propulsion unit and in the combustion chamber, and variation in specific heats with temperature. The principal performance charts show clearly the effects of the primary variables and correction charts provide the effects of the secondary variables" (p. 1).

Report presenting an analysis of the performance of compressor-turbine jet-propulsion systems carried out by calculating the thrust power from a compressor-turbine jet engine with a systematic variation of pressure ratio, fuel-air ratio, compressor and turbine efficiencies, flight speed, altitude, and maximum gas temperature.

"At the request of the Bureau of Aeronautics, Navy Department, tests were made in the 7- by 10-foot wind tunnel of the 1/8-scale model of the Brewster F2A airplane. The object of the tests was to determine the power-off static lateral and longitudinal stability and control of the complete model" (p. 1).

"Recent developments in airfoil-testing methods and fundamental air-flow investigations, as applied to airfoils, are discussed. Preliminary test results, obtained under conditions relatively free from stream turbulence and other disturbances, are presented. Suitable airfoils and airfoil-design principles were developed to take advantage of the unusually extensive laminar boundary layers that may be maintained under the improved testing conditions" (p. 1).

Report presenting testing made with simplified models of two types of hulls that differ considerably from conventional types. Both have a single main planing surface that is combined with after-planing surfaces placed directly below the aerodynamic tail surfaces. Results regarding an investigation of twin planing tails, a single-planing tail, and potentialities indicated by tests are provided.

Report presenting an analysis of the failure of adhesive bonds and its relation to boundary stress concentrations. A variety of material combinations, including metals and plastics, were examined and stress tested. The method of computing the thermal coefficients is applied to mixtures and especially to reinforced plastics.

Report presenting an investigation for the determination of the behavior of ceramic bodies in tension at elevated temperatures for the purpose of determining data for the design of ceramic blades for gas turbines. Observations were made of six special ceramic bodies in order to determine their tensile strength and creep during prolonged loading under a range of stresses and temperatures.

Report presenting a simple equation that can be used to facilitate the appraisal of the conventional jet as a means of propulsion. The equation can be used to estimate the performance of a large variety of aeropropulsive devices. The results using this equation indicate that attainable propulsive efficiencies at high speeds below sonic velocity are certain to be lower than is common at low speeds with the conventional propeller.

Report describes a procedure for instrumenting, testing, and presenting the overall characteristics of any engine turbosupercharger installation. The preflight analysis of the system, required testing, importance of accurate data recording, measurements to record, methods of measuring, and presentation of results are also included.

Tank tests were made of a hull model of the Hughes-Kaiser cargo airplane for estimates of take-off performance and maximum gross load for take-off. At hump speeds, with the model free to trim, the trim and resistance were high, which resulted in a load-resistance ratio of approximately 4.0 for a gross load coefficient of 0.75. With a 4000,000-lb load, the full size craft may take off in 69 sec over a distance of 5600 ft.

Report summarizes the available hinge-moment data for unshielded horn-balanced control surfaces. The purpose is to correlate the available data to assist with estimating the balance characteristics for use in the design and alteration of control surfaces with horn balances. Plan forms and variation of incremental hinge-moment-coefficient slopes with balance coefficients are presented.

"This report presents the results of systematic model experiments on the hydrodynamic characteristics of flying boats, aimed primarily at developing a comprehensive view of the factors influencing porpoising and of their relative importance. The experiments 'radiated' from a given reference ship; they embrace changes, over reasonably wide ranges, in the value of each of a number of variables, treated independently. The experimental results are summarized in a series of 25 figures, each of which gives the complete data for all the modifications of one variable" (p. 1).

Report presenting a series of outdoor tests to determine the static-thrust and torque characteristics of single- and dual-rotating propellers for use in aircraft propeller design and in take-off performance estimation.

Report presenting the results of nearly 200 tests made on the strength of shear webs of 24S-T aluminum alloy, with and without lightening holes. The tests were made in a jig of the single-specimen type, in which the specimen is free to collapse completely without developing diagonal tension. Results regarding the strength of the shear webs, stiffness of shear webs, and permanent-set tests are provided.

"The calculation of the stresses around cut-outs is discussed on the basis of a simplified application of the shear-lag theory previously published. Experimental stringer strains were measured around a systematic series of cut-outs. The test results indicate that the proposed method of calculating the stringer stresses is acceptable as a basis for stress analysis" (p. 1).

Report presenting an approximate method of applying the available data on various types of flaps in the design of fighter brakes together with several examples of its use. The computed effects of flap type, size, location, and deflection as well as the effects of altitude and initial velocities on braking characteristics are also shown in some examples using the method to determine various flap arrangements.

Bulletin presenting the results of an investigation to determine possible improvements in the tightness and the flushness of machine-countersunk rivets. Specimens used in the study were simple lap joints made by different riveting methods. The results indicate that a comparison of the quality of machine-countersunk riveted joints on the basis of maximum load alone is not justified.

Report discussing testing of aromatic amines as antiknock additives, and more specifically the suitability of overwater storage for these fuel blends. 12 aromatic amines of three different concentrations at two temperatures were measured. The chemical properties of the most promising fuel blends are described in more detail and correlations were noted.

Report presenting a study of the installation of 1800-horsepower engines in the PB2Y-3 airplane in place of the current 1200-horsepower engines. Stability and spray tests were made to determine the performance of the model on the water when tested at both the present and projected conditions of gross load and engine power. Results regarding aerodynamic tests and hydrodynamic tests are provided.

Report presenting an investigation to determine the effect of jet motors on the stability of the PB2Y-3 airplane at a gross load of 76,000 pounds. Results regarding Model 131J, Model 131J-1, and Model 131J-2 are provided.

Report discusses data obtained from testing shear of joints riveted with round-head and brazier-head rivets. The tightness of the rivets is also compared for one value of rivet diameter. The load-displacement curves and comparison of load at various values of permanent displacement are presented for both types of rivets.

Report discusses the results of testing on "10-inch shear panels of 24S-T aluminum alloy with 1.5 inch holes to determine the stress concentration at static rupture and the deformation characteristics" (from Summary). The strength of the perforated specimens is compared to the solid specimens and the critical stresses are computed. The stress at which permanent set occurs was also measured.

Report presenting testing in the two-dimensional tunnel of four models submitted by the Glenn L. Martin Company as intermediate sections of the wing of the XB-33 airplane. Each airfoil model had different types of flaps or no flaps at all. Results regarding the lift and drag data, lift coefficients, effect of flap positions, aileron effects, drag coefficients, and hinge-moment coefficients are provided.

Report discusses graphs of constants meant to be used with a knowledge of maximum total head loss, static-pressure decrement, and integral of total-head loss across the wake of an airfoil to determine the section profile-drag coefficient. Computations of free-stream Mach numbers for certain assumed types of total-pressure distribution in the wake are provided to compare theoretical drag coefficients as determined by other equations based on the momentum method. While some disagreements are found, the more rapid technique is usable for wide variations in wake shapes for a Mach number range of 0.5 to 1.0.