Report presenting a set of tables which aids in the numerical determination of the Fourier transform of a function of time and the inverse Fourier transform of a function of frequency. Many of the operations normally performed theoretically with the operational calculus can be performed numerically with the aid of the tables. Some applications using the tables are described.

Note presenting a theoretical study of the motions experienced by aircraft in response to sharp-edge, harmonic, and random gusts. These are compared with approximate solutions based on commonly used assumptions, and the validity of each of the assumptions is assessed.

Report presenting the similarity of Larson-Miller master curves for rupture life and minimum creep rate for aluminum, two aluminum alloys, two steels, and two high-temperature high-strength alloys. The approximate invariance of the product of rupture life and minimum creep rate is also shown for these materials.

Note presenting a determination of the accuracy with which pressure altitude can be measured by calculation of the errors in the measuring system, errors arising from operation of the system, and variations in atmospheric pressure. Some possibilities for reducing errors in the categories of altimeter-scale error, static-pressure error, atmospheric-reference error, flight technical error, friction error, and service error are provided.

Note presenting a series of tests comparing the mechanical properties of similar compressor blades of AISI type 403 stainless steel and thermenol. Eighth-stage J47 and J65 compressor blades of each material were tested.

From Summary: "An analysis is given of the oscillating motion of a ballistic missile which upon entering the atmosphere is angularly misaligned with respect to the flight path. The history of the motion for some example missiles is discussed from the point of view of the effect of the motion on the aerodynamic heating and loading. The miss distance at the target due to misalignment and to small accidental trim angles is treated. The stability problem is also discussed for the case where the missile is tumbling prior to atmospheric entry."

Report presenting calculations made to determine the vaporization rates of fuel drops in a rocket engine for sprays having various log-probability distributions of n-heptane drops. The rates were calculated for various engine design and operating parameters. Results regarding the geometric standard deviation, mass-median drop size, variation in group size, and a correlation of results are provided.

Report presenting local heat-transfer parameters on a hemisphere-cone-cylinder and a 120 degree included angle cone-cylinder at a free stream Mach number 3.12 and at a range of Reynolds numbers.

Report presenting a series of rolling-contact fatigue tests conducted in a bench rig at the Lewis laboratory. Four paraffin-base mineral oils of varying viscosity were used as lubricants. A continuous trend toward longer lift was observed with increasing lubricant viscosity over the range studied.

Note presenting an investigation to study the effect of ground proximity on the aerodynamic characteristics of a four-engine vertical-take-off-and-landing transport-airplane model with tilting wing and propellers. Tests were made with the wing at an angle of incidence of 90 degrees, the position used for vertical take-off or landing. Results regarding flow surveys and force tests are provided.

The importance of radiation as a means of cooling high-supersonic- and hypersonic-speed aircraft is discussed to show the need for measurements of the total hemispherical emissivity of surfaces. The theory underlying the measurement of the total hemispherical emissivity of surfaces is presented, readily duplicable apparatus for performing the measurements is described, and measurements for stably oxidized Inconel and Inconel X are given for the temperature range from 600 F to 2,000 F.

Report presenting wind-tunnel testing to determine the static-pressure error resulting from external interference effects of flow through the static-pressure orifices of an NACA airspeed head at Mach number 3 and 0 degrees angle of attack. The results showed that the static-pressure error increased almost linearly with increase in mass flow through the orifices.

A hydrodynamic rough-water impact-loads investigation of a fixed-trim V-bottom float with a beam-loading coefficient of 5.78 and dead-rise angle of 10 degrees was made at the Langley impact basin. The size of the waves varied from approximately 10 to 60 feet in length and 1 to 2 feet in height. Time histories were obtained showing the position of the model relative to the wave throughout the impact and typical examples are presented. The load coefficient was found to vary primarily with the slope of the impacting wave.

Note presenting pressure distributions on some simple sharp-nosed aerodynamic shapes at Mach numbers from 16 to 18 in helium flow. The results obtained for the flat plate differ from the prediction of Lees for the strong interaction region by an amount which may be accounted for by the finite thickness of the leading edge. Results regarding the temperature recovery, schileren observations, and pressure distributions are provided.

Note presenting weight-strength plots for circular cylindrical shells in bending. The ring-stiffened shell, the longitudinally stiffened shell, and shells constructed of waffle-like or sandwich-type plates are compared in order to evaluate the effect of type of stiffening on bending strength, and shells of various materials are compared to evaluate the effect of material properties. The effect of shear loads on the bending strength of cylinders is considered.

Report presenting a method of calculating the temperature of thick walls using relatively new concepts like the time series and response to a unit triangle variation of surface temperature. It is particularly suitable for determining the wall temperature in one-dimensional thermal problems in aeronautics with a continuous variation of the heat-transfer coefficient and adiabatic-wall temperature.

Report presenting an investigation in the high-speed 7- by 10-foot tunnel to determine the effects of variations in taper ratio within the range of 0.3 to 1.0 on the static lateral stability characteristics at high subsonic speeds of wing-fuselage combinations with wings of 45 degrees sweepback at the quarter-chord line and an aspect ratio of 4. Results regarding rolling-moment characteristics and lateral-force and yawing-moment characteristics are provided.

Report presenting drop-size-distribution data obtained for liquid jets atomized by cross-stream injection from simple orifices into high-velocity airstreams. A high-speed camera and a sampling technique were combined to obtain data over ranges of injector, liquid, and airstream variables.

Report presenting a method for the rapid prediction of the shape of attached shocks emanating from smoothly contoured axisymmetric and two-dimensional nose shapes. From a practical viewpoint, the accuracy of the method is comparable to that of the method of characteristics.

Note presenting an investigation of the problem of the influence of free-stream turbulence on the transfer of heat from a cylinder in forced convection at very low Mach numbers but at large Reynolds numbers. An attempt is made to determine whether the sole influence of turbulence is to shift the point of laminar separation in subcritical flow, or the point of transition in supercritical flow, and thus effect a change in the rate of heat transfer.

Note presenting testing on cermet blades in an axial-flow engine, which demonstrated that blade life of 150 hours at maximum turbine speed and exhaust temperature could be obtained. Fourteen tests were made with six test blades in the turbine rotor; two tests were made with only two cermet blades in operation. Results indicated that the two probably causes for the blades are impact and fatigue.

Note presenting a determination of the effect of initial temperatures from about 300 to 700 degrees Kelvin on the laminar burning velocity of hydrogen-air mixtures from schileren photographs of open flames. The temperature was raised in two ways: preheating the hydrogen-air mixtures and simulated adiabatic preburning of part of the hydrogen so that initial temperatures of 600 to 700 degrees kelvin would be attained for the resulting mixtures of hydrogen, air, water vapor, and nitrogen.

From Summary: "An investigation was carried out in the Langley stability tunnel to determine the lift, drag, and pitching-moment characteristics of a family of annular airfoils. The five annular airfoils had equal projected areas but had varying chords and diameters which covered aspect ratios of 1/3, 2/3, 1.0, 1.5, and 3.0. The results showed that the effects of aspect ratio on the aerodynamic-center location were similar for annular and unswept airfoils and that annular airfoils had larger maximum lift-drag ratios below an aspect ratio of 2.4 than did plane rectangular airfoils with faired tips."

Report presenting testing of a typical axial-flow compressor rotor with NACA 65-series compressor blades at low speeds and performance measurements were made over a range of quantity flow rates at several values of annulus-area ratio, blade-setting angle, solidity, and Reynolds number to compare with porous-wall cascade results. The conclusion was reached that two-dimensional-flow porous-wall cascade results can be used to estimate rotor performance with good accuracy over a wide range of conditions.