Report presenting burning rates for single isooctane drops suspended in various quiescent oxygen-nitrogen atmospheres at room temperature and pressure. The burning rates were compared with those predicted by a previously developed theory based on a heat- and mass-transfer mechanism and with values predicted by a modification to the theory.

Memorandum presenting the results of a test on the transonic longitudinal characteristics of a scale rocket model of the McDonnell XF3H-1 airplane. The model, flown with a center-of-gravity location of 28.5 percent of the mean aerodynamic chord and a stabilizer setting of -5.91 degrees relative to the wing chord plane, was equipped with extensible rocket racks. Results regarding the Reynolds number, rocket-rack program, flight time history, trim, lift, drag, longitudinal stability, directional stability, and inlet pressure recovery are provided.

Thermal-shock resistance of a ceramic comprising 60 percent boron carbide and 40 percent titanium diboride was investigated. The material has thermal shock resistance comparable to that of NBS body 4811C and that of zirconia, but is inferior to beryllia, alumina, and titanium-carbide ceramals. It is not considered suitable for turbine blades.

Report presenting results from a limited investigation of the use of controls during service operational training with four fighter airplanes. The service pilots utilized the positive V-n envelope in performing their training missions but rarely approached the negative V-n envelope. Results regarding the operational V-n diagram for the F-86A, F-84G, F2H-2, and F-84G, design curves, maximum elevator rates, maximum aileron rates, rolling velocities, and control surface angles are provided.

"A graphical method is described for finding the shape (camber and twist) of an airfoil having an arbitrary distribution of lift. The method consists in replacing the lifting surface and its wake with an equivalent arrangement of vortices and in finding the associated vertical velocities. By division of the vortex pattern into circular strips concentric about the downwash point instead of into the usual rectangular strips, the lifting surface is reduced for each downwash point to an equivalent loaded line for which the induced velocity is readily computed" (p. 543).

An extended form of the Ackeret iteration method, applicable to arbitrary profiles, is utilized to calculate the compressible flow at high subsonic velocities past an elliptic cylinder. The angle of attack to the direction of the undisturbed stream is small and the circulation is fixed by the Kutta condition at the trailing end of the major axis. The expression for the lifting force on the elliptic cylinder is derived and shows a first-step improvement of the Prandtl-Glauert rule. It is further shown that the expression for the lifting force, although derived specifically for an elliptic cylinder, may be extended to arbitrary symmetrical profiles.

"An analytical method is presented for calculating the hydrodynamic impact loads and motions experienced by seaplane floats and hulls with scalloped (fluted) bottoms. The analysis treats vertical impact at zero trim in addition to the more general problem of the step impact of a seaplane at positive trim where the flight path is oblique to the keel and to the water surface. Also considered are the transformations required to represent impacts into waves" (p. 109).

Report presenting an experimental investigation of a modified parabolic-bladed centrifugal impeller that was altered by cutting back every other blade to form splitter vanes. It was investigated over a range of equivalent impeller tip speeds and a range of flow rates. Results regarding the overall performance characteristics, a comparison of the splitter vane impeller and the fully bladed impeller, the maximum weight flow, and static-pressure ratios are provided.

Report presenting an investigation using the transonic-bump technique of some effects of sweep and thickness on the transonic downwash and wake characteristics of a series of highly tapered semispan wings with an aspect ratio of 3. Results regarding the downwash characteristics and wake characteristics are provided.

The significant findings of a theoretical study of column behavior in the plastic stress range are presented. When the behavior of a straight column is regarded as the limiting behavior of an imperfect column as the initial imperfection (lack of straightness) approaches zero, the departure from the straight configuration occurs at the tangent-modulus load. Without such a concept of the behavior of a straight column, one is led to the unrealistic conclusion that lateral deflection of the column can begin at any load between the tangent-modulus value and the Euler load, based on the original elastic modulus. A family of curves showing load against lateral deflection is presented for idealized h-section columns of various lengths and of various materials that have a systematic variation of their stress-strain curves.

"The formulas of subsonic and supersonic wing theory for source, doublet, and vortex distributions are reviewed and a systematic presentation is provided which relates these distributions to the pressure and to the vertical induced velocity in the plane of the wing. It is shown that care must be used in treating the singularities involved in the analysis and that the order of integration is not always reversible. Concepts suggested by the irreversibility of order of integration are shown to be useful in the inversion of singular integral equations when operational techniques are used. A number of examples are given to illustrate the methods presented, attention being directed to supersonic flight speed" (p. 1267).

"A lift-cancellation technique is presented for determining load distributions on thin wings at supersonic speeds. The loading on a wing having a prescribed plan form is expressed as the loading of a known related wing (such as a two-dimensional or triangular wing) minus the loading of an appropriate cancellation wing. The lift-cancellation technique can be used to find the loading on a large variety of wings. Applications to swept wings having curvilinear plan forms and to wings having reentrant side edges are indicated" (p. 65).

Report presenting a discussion of some of the requirements and of the application of the augmented performance of compressor coolant injection and afterburning in a turbojet engine in a high-speed, high-altitude flight. Results regarding the experimental performance of a combined system and the application of augmented performance to high-speed flight are provided.

From Summary: "Data from ditching investigations conducted at the Langley Aeronautical Laboratory with dynamic scale models of various airplanes are presented in the form of tables. The effects of design parameters on the ditching characteristics of airplanes, based on scale-model investigations and on reports of full-scale ditchings, are discussed. Various ditching aids are also discussed as a means of improving ditching behavior."

An investigation was undertaken to determine the characteristics of several basic types of thrust-reverser. Models of three types, target, tailpipe cascade, and ring cascade, were tested with unheated air. The effects of design variables on reverse-thrust performance, reversed-flow boundaries, and thrust modulation characteristics were determined.

Report presenting an experimental vaporizing annular combustor that evolved from a high-performance annular combustor developed for vapor-fuel injection. The combustor consisted of a one-quarter sector of a single-annulus combustor designed to fit in a housing with an outside diameter of 25.5 inches, an inside diameter of 10.6 inches, and a combustor length of approximate 23 inches. Results regarding the performance of the Model 29I combustor, performance of Model 30, and performance of the best combustor configuration are provided.

From Summary: "Several methods of obtaining the time response of Linear systems to either a unit impulse or an arbitrary input from frequency-response data are described and compared. Comparisons indicate that all the methods give good accuracy when applied to a second-order system; the main difference is the required computing time. The methods generally classified as inverse Laplace transform methods were found to be most effective in determining the response to a unit impulse from frequency-response data of higher order systems. Some discussion and examples are given of the use of such methods as flight-data-analysis techniques in predicting loads and motions of a flexible aircraft on the basis of simple calculations when the aircraft frequency response is known."

From Summary: "Some factors relating to inadvertent speed and Mach number increases in transport operation are discussed with the object of indicating the manner in which they might vary with different qualities of the airplane and the minimum margins required to guard against reaching unsafe values. The speed increments and the margins required under several assumed conditions are investigated. The results indicate that, on a percentage basis, smaller margins should be required of high-speed airplanes than of low-speed airplanes to prevent overspeeding in inadvertent maneuvers."

Report presenting comparisons of low-lift drag measurements on eight airplane configurations at a range of Mach numbers using various techniques. Data was obtained from wind-tunnel testing, rocket-propelled model testing, and airplane flight testing. The majority of the data showed agreement and discrepancies were likely due to issues regarding surface condition, individual test setup and accuracy, and detail geometric differences between the airplanes and respective models.

From Summary: "The results of tests of a slender body of revolution designated the NACA rm-10 have been compiled from various NACA test facilities. Zero-lift drag data are presented for a Reynolds number range from about 1 x 10(6) to 40 x 10(6) from several wind tunnels and from about 12 x 10(6) to 140 x 10(6) from free-flight tests. The Mach numbers covered include 1.5 to 2.4 for the wind-tunnel data and 0.85 to 2.5 for the flight results. The wind tunnel models were tested with and without 60 degree sweptback stabilizing fins and the flight models were tested with stabilizing fins."

Report presenting an investigation of the performance characteristics of a mixed-flow impeller (Model MFI-1B) in combination with a vaned diffuser. The results indicated that the peak pressure ratio and maximum efficiency were not being obtained at overdesign speeds because of premature surge. Increasing inlet angle at the leading edge of the vanes improved the pressure ratio and efficiency at overdesign speeds with little to no effect on underdesign speeds.

Report presenting an analysis of the problems associated with matching secondary-air requirements of ejector exhaust nozzles and auxiliary inlets has been made for free-stream Mach numbers up to 2.0. The analysis indicated that inlets located in the free stream supply higher pressure recovery than ejectors generally require for optimum net internal thrust at Mach numbers above about 1.4. Net-thrust gains can be achieved by immersing the auxiliary inlet in a boundary layer where the inlet-momentum penalty is less.

"A primary objective of turbine research is to obtain information that will aid in the design of gas turbines for any given application with minimum losses. As part of a program to obtain such information, flow surveys downstream of both the stator and the rotor of an experimental turbine were made in order to obtain detailed information about the flow conditions and the losses within the machine. The single-stage, low-radius-ratio turbine studied is relatively conservative in design, having low rotor-inlet relative Mach number, low turning angle, and high reaction at the rotor-root section" (p. 1).

Report presenting the lateral stability and control characteristics of the Convair YF-102 airplane during flights for the NACA research program. The investigation included gradually increasing sideslips, rudder-fixed aileron rolls, rudder pulses, and trim runs at two different altitudes over the test Mach number range. The lateral handling characteristics appeared satisfactory when viewed in terms of gradually increasing sideslips.