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Analysis of Off-Design Operation of High Mach Number Supersonic Turbojet Engines
From Introduction: "Because of the lack of data on compressor characteristics at 130 or 145 percent of design equivalent rotational speed, several simplifying assumptions were made regarding the compressor characteristics during operation at equivalent rotational speeds above the design value (hereinafter called "compressor overspeeding"). In addition to results based on these assumptions, the effect of deviation from these assumptions is discussed."
Analytical study of losses at off-design conditions for a fixed geometry turbine
From Introduction: "The purpose of this report is to present the results of the analytical investigation of the turbine of reference 1 to indicate the extent to which the various turbine losses affect the turbine efficiency over the range of performance."
Buffeting forces on two-dimensional airfoils as affected by thickness and thickness distribution
Report presenting an experimental investigation to determine the effect of thickness and of thickness distribution on the fluctuations of normal-force and pitching-moment coefficients of airfoils. Seven symmetrical airfoils were tested. Two types of pressure pulsations were noted in the study: pulsations from an intermittent build-up and dropping of the pressure peak near the leading edge and pulsations attributable to shock-wave motion and unsteady air flow following the shock wave.
Effect of Turbine Axial Nozzle-Wheel Clearance on Performance of Mark 25 Torpedo Power Plant
"Investigations were made of the turbine from a Mark 25 torpedo to determine the performance of the unit with three different turbine nozzles at various axial nozzle-wheel clearances. Turbine efficiency with a reamed nondivergent nozzle that uses the axial clearance space for gas expansion was little affected by increasing the axial running clearance from 0.030 to 0.150 inch. Turbine efficiency with cast nozzles that expanded the gas inside the nozzle passage was found to be sensitive to increased axial nozzle-wheel clearance" (p. 1).
Effects of increasing Reynolds number from 2 x 10(exp 6) to 6 x 10(exp 6) on the aerodynamic characteristics at transonic speeds of a 45 degree swept wing with 6 degree leading-edge droop
Report presenting an investigation in the 16-foot and 8-foot transonic tunnel to determine the effects of Reynolds number and on a swept wing with camber. The wing had 45 degrees sweepback of the quarter-chord line, an aspect ratio of 4, a taper ratio of 0.6, and NACA 65A006 airfoil sections parallel to the plane of symmetry. Results regarding the effect of Reynolds number on the aerodynamic characteristics and effects of roughness strips are provided.
Flight Experience With Two High-Speed Airplanes Having Violent Lateral-Longitudinal Coupling in Aileron Rolls
"During flight tests of two high-speed airplane configurations, violent cross-coupled lateral and longitudinal motions were encountered following abrupt rudder-fixed aileron rolls. The speeds involved ranged from a Mach number of 0.7 to 1.05. The motions were characterized by extreme variations in angles of attack and sideslip which resulted in load factors as large as 6.7g (negative) and 7g (positive) normal acceleration and 2g transverse acceleration" (p. 1).
Free-Spinning-Tunnel Tests of a 1/24-Scale Model of the Grumman XF9F-2 Airplane, TED No. NACA DE 317
"An investigation of the spin and recovery characteristics of a scale model of the Grumman XF9F-2 airplane has been conducted in the Langley 20-foot free-spinning tunnel. The effects of control settings and movements on the erect and inverted spin and recovery characteristics of the model in the flight loading were determined. The investigation also included spin-recovery-parachute, pilot-escape, and rudder-pedal- . force tests" (p. 1).
Preliminary Investigation at Low Speeds of Swept Wings in Yawing Flow
Memorandum presenting a wind-tunnel investigation conducted to determine the rotary stability characteristics in yawing flow of a series of untapered wings with angles of sweep of -45, 0, 45, and 60 degrees. The results of the yawing-flow tests indicated that the values of the rotary derivatives agreed fairly well with simple sweep theory for a moderate range of lift coefficients.
Preliminary Investigation of Cyclic De-Icing of an Airfoil Using an External Electric Heater
"An investigation was conducted in the NACA Lewis icing research tunnel to determine the characteristics and requirements of cyclic deicing of a 65,2-216 airfoil by use of an external electric heater. The present investigation was limited to an airspeed of 175 miles per hour. Data are presented to show the effects of variations in heat-on and heat-off periods, ambient air temperature, liquid-water content, angle of attack, and. heating distribution on the requirements for cyclic deicing" (p. 1).
A preliminary study of the preparation of slurry fuels from vaporized magnesium
"Slurry fuels containing extremely small particles of magnesium were prepared by concentrating the dilute slurry product resulting from the shock-cooling of magnesium metal vapors with a liquid hydrocarbon spray. A complete description of the equipment and procedure used in preparing the fuel is given. Ninety-five percent by weight of the solid particles formed by this process passed through a 100-mesh screen. The particle-size distribution of the screened fraction of one run, as determined by sedimentation analysis, indicated that 73 percent by weight of the metal particles were finer than 2 microns in equivalent spherical diameter" (p. 1).
Results of free-flight test of 1/10-scale model of the Convair XF2Y-1 airplane between Mach numbers of 0.7 and 1.45, including power-on flight at Mach number 1.2: TED No. NACA DE 365
Report presenting a scale model of the Convair XF2Y-1 airplane with a solid-fuel rocket motor designed to simulate full-scale turbojet engine characteristics with full afterburning at a Mach number 1.2 and an altitude of 35,000 feet in free flight at a maximum Mach number of 1.45. Results regarding stability characteristics, trim characteristics, and the effect of rocket exhaust over the beaches are provided.
Results of Measurements Made During the Approach and Landing of Seven High-Speed Research Airplanes
Memorandum presenting an investigation of the landing characteristics of the X-1, X-3, and D-558-I straight-wing, the X-4, X-5, and D-558-II swept-wing, and the XF-92A delta-wing high-speed research airplanes. Results regarding normal landings, vertical velocities at ground contact, ground effect, and effects of lift-drag ratio are provided.
Some Results of Flight Testing of Ski-Equipped Aircraft at the Naval Air Test Center
Memorandum presenting the results of flight testing of four different ski-equipped airplanes. Two types of skis were tested: hydro-skis designed to operate under or on the water surface and general-purpose skis designed to operate on a variety of surfaces but not underwater. A breakdown of the ski performance for each plane and ski combination is provided.
Two-Dimensional Wind-Tunnel Investigation at High Reynolds Numbers of an NACA 65A006 Airfoil With High-Lift Devices
Report presenting an investigation of an NACA 65A006 airfoil equipped with high-lift devices, including a 0.15-chord drooped-nose flap and a 0.20-chord plain trailing-edge flap. Airfoil section lift, pitching-moment, and drag characteristics obtained at high Reynolds numbers and low Mach numbers with the flaps deflected individually and simultaneously are presented. At Reynolds numbers up to 9.0 x 10(exp 6), the optimum combination of drooped-nose and plain trailing-edge flaps increased the maximum section lift coefficients from 0.78 to 1.89.
Vibratory-Stress Investigation of Six- and Eight-Blade-Dual-Rotating Propellers Operating at Zero Advance
Report presenting the results of an investigation of the vibratory stresses of a dual-rotating propeller with both six-blade and eight-blade configurations using the NACA 6,000-horsepower propeller dynamometer. Attention was focused on the measurement of vibratory stresses caused by mutual blade interference of the front- and rear-propeller components. A range of blade angles and rotational speeds were used in testing.
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