Memorandum presenting an investigation to determine the dynamic lateral stability characteristics of a configuration of the North American X-15 research airplane. Of specific concern were characteristic modes, period and damping, airplane response to yaw and roll controls, ratio of roll to sideslip in the Dutch-roll oscillation, and the roll-coupling problem. Results regarding stability-boundary plots, characteristic roots, roll-to-sideslip ratio, and time histories are provided.

Report discussing an investigation of a parabolic body of revolution with and without the effects of an annular jet exhausting from the base. The aerodynamic characteristics, pressures, lift-curve slope, and other characteristics with the jet in operation and inoperative were compared.

A low-speed wind-tunnel investigation was made to determine the lateral control characteristics of a series of untapered low-aspect-ratio wings. Sealed flap ailerons of various spans and spanwise locations were investigated on unswept wings of aspect ratios 1.13, 1.13, 4.13, and 6.13; and various projections of 0.60-semispan retractable ailerons were investigated on the unsweptback wings of aspect ratios 1.13, 2.13, and 4.13 and on a 45 degree sweptback wing. The retractable ailerons investigated on the unswept wings spanned the outboard stations of each wing; whereas the plain and stepped retractable ailerons investigated on the sweptback wing were located at various spanwise stations. Design charts based on experimental results are presented for estimating the flap aileron effectiveness for low-aspect-ratio, untapered, unswept.

Report presents results of tests made on a power control system by means of a ground simulator to determine the effects of various combinations of valve friction and stick friction on the ability of the pilot to control the system. Various friction conditions were simulated with a rigid control system, a flexible system, and a rigid system having some backlash. For the tests, the period and damping of the simulated airplane were held constant.

A series method of determining two-dimensional vortex paths is considered and applied to the computation of vortex positions behind a slender equal-span cruciform wing at any angle of bank as a function of the distance behind the trailing edge. Calculated paths are shown for four bank angles. For a bank angle of 45 degrees comparison is made with the results of a closed expression given in NACA-TN-2605. For other bank angles water-tank experiments provide qualitative comparison. Satisfactory agreement is found for a sufficient distance downstream to include most practical missile-tail positions. The interference forces on an equal-span cruciform wing are calculated for five angles of bank (including the trivial case of zero bank) from the vortex positions found by use of the series.

"Increasing demands for higher afterburner performance have required operation at progressively higher fuel-air ratios, which has increased the occurrence and intensity of screeching combustion. The onset of screech may be followed by rapid destruction of the combustor shell and other combustor parts. Because of its destructive characteristics, considerable effort has been expended to understand and eliminate screech. NACA work on the screeching combustion problem prior to 1954 is summarized herein" (p. 1195).

"This report summarizes the effects of fuel volatility and engine design variables on the problem of starting gas-turbine engines at sea-level and altitude conditions. The starting operation for engines with tubular combustors is considered as three steps; namely, (1) ignition of a fuel-air mixture in the combustor, (2) propagation of flame through cross-fire tubes to all combustors, and (3) acceleration of the engine from windmilling or starting speed to the operating speed range. Pertinent data from laboratory researches, single-combustor studies, and full-scale engine investigations are presented on each phase of the starting problem" (p. 1).

Report presenting a preliminary study to determine the possibility of utilizing a wingless configuration as a guided missile. The results indicated that the maximum trimmed lift coefficient developed by the wingless missile was somewhat smaller than that of the winged missile at a Mach number of 2.4.

Report presenting an investigation of an airplane configuration model with a 45 degree swept wing of aspect ratio 4.0 and a taper ratio 0.3 with a low swept horizontal tail to determine its longitudinal stability. Longitudinal aerodynamic coefficients and stability derivatives are presented as functions of Mach number over the test range. The results are compared to wind tunnel and rocket model data and generally show good agreement.

Memorandum presenting a preliminary free-flight study of the drag and stability of a series of short-span missile configurations with 80, 85, and 90 degrees of fin leading-edge sweep. Increasing the fin sweep decreased the drag markedly.

Report discussing testing of a helicopter rotor powered by pulse-jet engines located at the rotor-blade tips. The basic hovering characteristics of the rotor and propulsive characteristics of the pulse-jet engine were obtained at a range of engine speeds with the engines rigidly fixed to the blade tips and with the engines free to pivot. Measurements were also taken to determine the effect of inlet blockage on the power-off drag of the jet engines and the noise intensity in the vicinity of operating engines.

Memorandum presenting testing of a D-558-II airplane with the wing slats fully extended, with and without inboard wing fences, and with the wing slats half extended and wing fences removed. In order to improve the stick-force characteristics at moderate and large angles of attack, additional tests were conducted with two bungees of differing stiffness alternately attached to the control column.

Report presenting an investigation in the high-speed tunnel using the transonic-bump method to determine the characteristics of a jet control consisting of numerous holes located at the 65-percent chord line of a 35 degree swept semispan wing with an NACA 65A006 airfoil section. Testing occurred over a range of Mach numbers, angles of attack, and ejection-pressure ratios. Results regarding rolling-moment coefficients and aerodynamic characteristics in pitch are provided.

Report discussing a low-lift lateral stability investigation with a rocket-propelled model of a 45 degree swept-wing-airplane configuration equipped with an auxiliary yaw-rate damper system at a range of Mach numbers. Results indicated that the system was nonlinear due to a large dead spot in the system. The primary effect of the system was to increase the damping of lateral oscillations.

Report presenting an investigation to determine the dynamic lateral stability characteristics of a configuration of the North American X-15 research airplane. The characteristic modes, period and damping, airplane responses to yaw and roll controls, ratio of roll to sideslip in the Dutch-roll oscillation, and the roll-coupling problem are the primary focus.

Memorandum presenting a study of the chemical and physical properties of the high-energy fuel HEF-2. The properties measured included elemental analysis, heat of combustion, density, freezing point, self-ignition temperature, flash point, viscosity, molecular weight, vapor pressure, refractive index, and the water and oxygen stability.

Air was bled over the fifth-and tenth-stage rotor-blade rows through ports designed to pass 11 and 9 percent of the inlet flow, respectively, at 80 percent speed. Along the rated operating line the maximum speed at which rotating stall was encountered was lowered by either of these bleeds, and the stall patterns below these speeds were altered so that no dangerous resonant rotor-blade bending vibrations were excited. The combination of the two bleeds completely eliminated rotating stall to at least 50 percent speed. The compressor-discharge weight flow was decreased only at intermediate speeds, and the overall pressure ratio was affected only at intermediate speeds, and the overall pressure ratio was affected only by the combination bleed at intermediate speeds. Fifth-stage bleed increased compressor efficiency at low speeds, and tenth-stage bleed decreased efficiency at intermediate speeds.

Report presenting an exploratory investigation to determine the effects of wing slots on the longitudinal stability characteristics of a 45 degree sweptback wing-fuselage combination. Results regarding pitching-moment characteristics and lift and drag characteristics are provided.

Report presenting an investigation at a range of Mach numbers from 0.7 to 1.4 to determine the effect of scale on the zero-lift drag of a fin-stabilized body of revolution and a fighter-type airplane configuration. Results obtained at low values of Reynolds number were compared with larger scale data obtained on geometrically similar models in free flight. Results regarding fin-stabilized body and airplane model are provided.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Price Daniel, regarding a legal question submitted for clarification: Authority of the sheriff to order photographs to be taken in connection with an investigation of a crime without first securing approval by the commissioners' court or the county auditor.

Report issued by the Oak Ridge National Laboratory discussing the Research Reactor (ORR). General descriptions of the ORR are presented. This report includes tables, and illustrations.

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Abstract: Beehive is a five energy group, two region, time independent spherical reactor code. It considers the problem of reactor system in which the core material is assumed to be at a higher energy (temperature) than the reflector material. The code obtains a closed solution for the critical reactor assembly by a procedure which is a logical extension of normal two group theory. The companion code, Hornet, computes the neutron fluxes for the critical assembly determined by the Beehive calculation. Both codes have been programmed for the IBM Magnetic Drum Data-Processing Machine, Type 650. The codes, together with the flow diagrams, are included with this report.

Introduction: "This report covers the contributions of UCRL to MTA research and development program during the period June 1 to November 30, 1953. In this program UCRL continues to work in close collaboration with the California Research and Development Company (CRD)."