Report presents the results of an investigation conducted to determine the hydrodynamic forces and moments acting on modified rectangular flat plates with aspect ratios of 1.00, 0.25, and 0.125 mounted on a single strut and operating at several depths of submersion. A simple method has been developed by modification of Falkner's vortex-lattice theory which enables the prediction of the lift characteristics in unseparated flow at large depths. This method shows good agreement with experimental data from the present tests and with aerodynamic data at all angles investigated for aspect ratios of 1.00 and 0.25 and at angles up to 16 degrees for aspect ratio 0.125. Above 16 degrees for aspect ratio 0.125, the predicted lift proved too high.

An experimental study is presented of the pressure fluctuations near jet exhaust streams made during unchoked operation of a turbojet engine and a 1-inch-diameter high-temperature model jet and during choked operation of various sizes of model jets with unheated air. The tests for unchoked operation indicate a random spectrum of rather narrow band width which varies in frequency content with axial position along the jet. Pressure surveys from the model tests along lines parallel to the 15 degree jet boundary indicate that the station of greatest pressure fluctuations is determined by the jet velocity and the radial distance, with a tendency of the maximum to shift downstream as either parameter is increased.

Memorandum presenting cooling data for a transpiration-cooled afterburner with a porous combustion-chamber wall of brazed and rolled wire cloth for a range of exhaust-gas temperatures, total flow ratio of cooling air to combustion gas, and pressure altitudes. Maximum wall temperatures based on the cooling correlation were determined for a porous wall of uniform permeability at sea-level takeoff and for several flight Mach numbers. Results regarding typical data, cooling correlation, transpiration-cooling performance, comparison of transpiration and forced-convection cooling, and pressure environment of wire cloth are provided.

From Summary: "Lateral and longitudinal combustion-pressure oscillations that occurred in screaming combustion of a 1000-pound-thrust rocket engine using white fuming nitric acid and JP-4 fuel as propellants were successfully prevented by means of longitudinal fins in the combustion chamber. Fin position was critical, and complete attenuation was achieved only when the fins were located in a zone approximately 8 to 16 inches from the injector. Fins located in other zones, that is, near the injector or far downstream from the injector, did not stop the oscillations."

Report discussing an investigation to determine the aileron effectiveness and damping in roll of the Hughes Falcon missile, D configuration at several Mach numbers. Information about the rolling-moment coefficient, damping-in-roll derivative, and drag coefficient is provided.

Memorandum presenting a model bomb-release investigation conducted in the 9-inch supersonic tunnel at a Mach number of 1.62 to determine what first-order interference effects are involved in making releases at supersonic speeds and, in some cases, to ascertain what modifications might be made to obtain near-level drops. The results of these tests indicate that the interference effects of the fuselage or wing-pylon upon the bomb release are, in most cases, adverse.

Memorandum presenting the compatibility of pentaborane with aluminum foil, 24S-T and 17S-T aluminum, and 50-50 tin-lead solder in the range of -30 to -50 degrees F for 7 hours, at 90 degrees F for 6.5 hours, and at 70 degrees F for 28 days. Results were evaluated by determination of the loss in weight after the test period, metallographic inspection, and comparison with blanks carried through test conditions without exposure to the liquid. The evaluation of results was made by visual inspection and physical tests of dimensional stability, tensile strength, elasticity, and gain or loss of weight.

Report presenting an investigation to determine the effects of two spinner shapes on the pressure recovery in an NACA 1-series D-type cowl behind a three-blade propeller with fairly thick shanks. Data were obtained at a range of Mach numbers, inlet velocity ratios, blade angle ratios, and a specified Reynolds number.

The interaction of the flow from one convergent and two convergent-divergent nozzles on parabolic afterbodies was studied at free-stream Mach numbers of 2.0, 1.6, and 0.6 over a range of jet pressure ratio. The influence of the jet on boattail and base drag was very pronounced. Study of the total external afterbody drag values at supersonic speeds indicated that, over most of the high-pressure-ratio range, increasing the nozzle design expansion ratio increased the drag even though the boattail area was reduced. Increasing the pressure ratio tended to increase slightly the total-drag increment caused by angle-of-attack operation.

Report presenting an investigation in the stability tunnel to determine the low-speed yawing derivatives of a 0.085-scale model of the Chance Vought XF8U-1 airplane and to determine the static longitudinal and static lateral stability characteristics in order to provide a basis for comparison with other data sources.

From Summary: "An investigation was conducted in the 8- by 6-foot supersonic wind tunnel on the external and internal characteristics of a plug-type exhaust nozzle. Two positions of the center plug, one simulating a convergent nozzle and the other a convergent-divergent nozzle, were investigated. Data were obtained at free-stream Mach numbers of 0.1, 0.6, 1.6, and 2.0 over a pressure-ratio range of 1 to 20 and angles of attack of zero and 8 degrees. Results of this investigation indicated that the plug nozzle had thrust-minus-drag performance over the entire pressure-ratio range comparable with equivalent conventional nozzles."

Memorandum presenting a comparison made between the incremental aerodynamic root bending moments on the horizontal tail of a jet-powered bomber airplane measured during a flight investigation over a range of Mach numbers and the bending moments calculated by using available theoretical models in conjunction with measured loads, elevator positions, and elevator and stabilizer twists. Results regarding abrupt maneuvers, gradual turn maneuvers, and effects of downwash are provided.

Report presenting an experimental study of the compression fields around axially symmetric isentropic spikes with varying degrees of compressive flow turning made at a Mach number of 3.85 to analyze the basic shock structures and thereby establish further design criteria for supersonic-inlet applications. Results regarding the original isentropic spike and cowl, isentropic survey-spike configurations, and external-compression limitations are provided.

Report presenting an investigation to obtain forced-convection heat-transfer and pressure-drop data for flow of air between electrically heated parallel flat plates stacked to form passages of short length-to-effective-diameter ratio. The primary purpose of the investigation is to determine the interference effects of the upstream stack of plates on the heat-transfer and friction characteristics of the downstream stack. Results regarding the plate temperature gradients, heat-transfer data, and friction data are provided.

Report presenting an experimental investigation on eight double-shroud ejector configurations with a current production-type turbojet engine and an afterburner as the primary gas generator. Air-flow and thrust characteristics of each ejector configuration are presented for a range of operating pressure ratios and weight-flow ratios at representative nonafterburning or afterburning primary gas temperatures.

Report presenting an investigation in the high-speed 7- by 10-foot tunnel to determine the effects of a wing leading-edge modification on the effectiveness of a spoiler-slot-deflector control. The modification consisted of a chord extension over the outboard 35 percent of the semispan in combination with a full-span leading-edge flap deflected 6 degrees.

Report presenting a free-flight investigation over a range of Mach numbers near zero lift to determine the aileron effectiveness and damping in roll of the full-scale Hughes Falcon missile, D configuration.

Report presenting the performance of a twin-duct air-intake system utilizing a double-oblique-shock inlet with a variable second ramp at several Mach numbers. Testing was conducted over a range of angles of attack and yaw, mass-flow ratio, and variable-ramp angle.

Memorandum presenting a consideration of the problems, research status, and future possibilities for high-temperature lubricants and bearings for aircraft turbine engines. The greater heat loads imposed by high-performance engines and practical limitation on cooling will result in increased operating temperatures for bearings and lubricants.

Report presenting testing of a 14-inch supersonic mixed-flow rotor with a supersonic leading edge and an inlet radius ratio of 0.52, which was designed for impulse operation and uniform work output and tested in Freon-12. Results regarding overall rotor performance, entrance flow, distribution of static pressure on the casing, and exit flow are provided.

This report lists pertinent NACA papers presenting research results which have a direct bearing on control system design and performance for both piloted and automatically controlled aircraft. Limited reference is also made to NACA reports on aircraft engine controls and to research techniques and instrumentation pertinent to the study of control systems and aircraft dynamics in flight. Reports published between January 1949 and April 1954 are listed in chronological order and cross referenced.

Report presenting normal-force and pressure distributions for a body of revolution consisting of a fineness-ratio-3, circular-arc, ogival nose tangent to a cylindrical afterbody 7 diameters long. Comparisons of theoretical and experimental distributions indicate that available theoretical methods are only accurate for angles of attack up to about 5 degrees.

Report presenting cooling data for a transpiration-cooled afterburner with a porous combustion-chamber wall of brazed and and rolled wire cloth for a range of exhaust-gas temperatures, total flow ratios of cooling air to combustion gas, and pressure altitudes. Results regarding typical data, cooling correlation, transpiration-cooling performance, comparison of transpiration and forced-convection cooling, and pressure environment of the wire cloth are provided.

Report presenting testing using a 1 7/8-inch inside-diameter combustor that can measure and compare the blow-out velocities of single-component fuels, slurries, and fuel mixtures with a wide range of reactivity and physical properties. The blow-out velocities of isooctane, n-heptane, isopentane, allyl chloride, and propylene oxide varied int he same way as flame speeds of the fuels. Results regarding the effects of different additives are also provided.