National Advisory Committee for Aeronautics (NACA) - 45 Matching Results

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Effect of body nose shape on the propulsive efficiency of a propeller

Description: Report presents the results of an investigation of the propulsive efficiency of three adjustable propellers of 10-foot diameter operated in front of four body nose shapes, varying from streamline nose that continued through the propeller plane in the form of a large spinner to a conventional open-nose radial-engine cowling. One propeller had airfoil sections close to the hub, the second had conventional round blade shanks, and the third differed from the second only in pitch distribution. The blade-angle settings ranged from 20 degrees to 55 degrees at the 0.75 radius.
Date: January 29, 1940
Creator: Stickle, George W.; Crigler, John L. & Naiman, Irven
Partner: UNT Libraries Government Documents Department

Preliminary investigation of the flying qualities of airplanes

Description: "The National Advisory Committee for Aeronautics is undertaking an investigation of the flying qualities of airplanes. The work consists in the determination of the significant qualities susceptible of measurement, the development of the instruments required to make the measurements, and the accumulation of data on the flying qualities of existing airplanes, which data are to serve as a basis for quantitative specifications for the flying qualities of future designs" (p. 449).
Date: March 29, 1940
Creator: Soulé, H. A.
Partner: UNT Libraries Government Documents Department

The calculated effect of various hydrodynamic and aerodynamic factors on the take-off of a large flying boat

Description: Report presents the results of an investigation made to determine the influence of various factors on the take-off performance of a hypothetical large flying boat by means of take-off calculations. The factors varied in the calculations were size of hull (load coefficient), wing setting, trim, deflection of flap, wing loading, aspect ratio, and parasite drag. The take-off times and distances were calculated to the stalling speeds and the performance above these speeds was separately studied to determine piloting technique for optimum take-off.
Date: April 29, 1940
Creator: Olson, R. E. & Allison, J. M.
Partner: UNT Libraries Government Documents Department

Longitudinal characteristics and aileron effectiveness of a midwing airplane from high-speed wind tunnel tests

Description: Report presenting wind-tunnel tests of a 0.175-scale model of a midwing airplane in order to determine the high-speed longitudinal characteristics, to test devices for improving longitudinal control at high Mach numbers, and to determine the aileron effectiveness at high Mach numbers. Force and moment coefficients are computed from test data. Control forces, elevator angle, and aileron angle for several flight conditions are predicted.
Date: September 29, 1944
Creator: Hall, Charles F. & Mannes, Robert L.
Partner: UNT Libraries Government Documents Department

On the flow of a compressible fluid by the hodograph method 2: fundamental set of particular flow solutions of the Chaplygin differential equation

Description: From Summary: "The differential equation of Chaplygin's jet problem is utilized to give a systematic development of particular solutions of the hodograph flow equations, which extends the treatment of Chaplygin into the supersonic range and completes the set of particular solutions. The particular solutions serve to place on a reasonable basis the use of velocity correction formulas for the comparison of incompressible and compressible flows. It is shown that the geometric-mean type of velocity correction formula introduced in part I has significance as an over-all type of approximation in the subsonic range."
Date: September 29, 1944
Creator: Garrick, I. E. & Kaplan, Carl
Partner: UNT Libraries Government Documents Department

On the Flow of a Compressible Fluid by the Hodograph Method. II - Fundamental Set of Particular Flow Solutions of the Chaplygin Differential Equation

Description: From Summary: "The differential equation of Chaplygin's jet problem is utilized to give a systematic development of particular solutions of the hodograph flow equations, which extends the treatment of Chaplygin into the supersonic range and completes the set of particular solutions. The particular solutions serve to place on a reasonable basis the use of velocity correction formulas for the comparison of incompressible and compressible flows. It is shown that the geometric-mean type of velocity correction formula introduced in part I has significance as an over-all type of approximation in the subsonic range."
Date: September 29, 1944
Creator: Garrick, I. E. & Kaplan, Carl
Partner: UNT Libraries Government Documents Department

Extension of Useful Operating Range of Axial-Flow Compressors by Use of Adjustable Stator Blades

Description: "A theory has been developed for resetting the blade angles of an axial-flow compressor in order to improve the performance at speeds and flows other than the design and thus extend the useful operating range of the compressor. The theory is readily applicable to the resetting of both rotor and stator blades or to the resetting of only the stator blades and is based on adjustment of the blade angles to obtain lift coefficients at which the blades will operate efficiently. Calculations were made for resetting the stator blades of the NACA eight-stage axial-flow compressor for 75 percent of design speed and a series of load coefficients ranging from 0.28 to 0.70 with rotor blades left at the design setting" (p. 425).
Date: December 29, 1944
Creator: Sinnette, John T., Jr. & Voss, William J.
Partner: UNT Libraries Government Documents Department

Measurement of individual aileron hinge moments and aileron control characteristics of a P-40F airplane

Description: From Summary: "Flight measurements have been made of the individual aileron hinge moments, aileron rolling effectiveness pb/2V ,and stick-force characteristics in abrupt aileron rolls with a P-40F airplane (AAF No. 41-14119) over an indicated airspeed range from 108 to 304 miles per hour. Three methods for measuring the rate of change of hinge moment with angle of attack were investigated. Presented for comparison with the flight results are data from two-dimensional wind-tunnel tests of the wing-aileron profile as measured at the center aileron hinge."
Date: January 29, 1945
Creator: Goranson, R. Fabian
Partner: UNT Libraries Government Documents Department

Wind-Tunnel Tests of a Portion of a PV-2 Helicopter Rotor Blade

Description: From Summary: "A portion of a PV-2 helicopter rotor blade has been tested in the 6- by 6-foot test section of the Langley stability tunnel to determine if the aerodynamic characteristics were seriously affected by cross flow or fabric distortion. The outer portion of the blade was tested as a reflection plane model pivoted about the tunnel wall to obtain various angles of cross flow over the blade. Because the tunnel wall acts as a plane of symmetry, the measured aerodynamic characteristics correspond to those of an airfoil having various angles of sweepforward and sweepback. Tests were made with the vents on the lower surface open and also with the vents sealed and the internal pressure held at -20 inches of water producing an internal pressure coefficient of -1.059."
Date: March 29, 1945
Creator: Kemp, William B., Jr.
Partner: UNT Libraries Government Documents Department

A method for the calculation of external lift, moment, and pressure drag of slender open-nose bodies of revolution at supersonic speeds

Description: An approximate method is presented for the calculation of the external lift, moment, and pressure drag of slender open-nose bodies of revolution of supersonic speeds. The lift, moment, and pressure drag of a typical ram-jet body shape are calculated at Mach numbers 1.45, 1.60, 1.75, and 3.00; and the lift and moment results are compared with available experimental data. The agreement of the calculated lift and moment data with the experimental data is excellent. The pressure-drag comparison was not presented because of the uncertainty of the amount of skin-friction drag present in the experimental results.
Date: December 29, 1945
Creator: Brown, Clinton E. & Parker, Hermon M.
Partner: UNT Libraries Government Documents Department

Application of the method of characteristics to supersonic rotational flow

Description: A system for calculating the physical properties of supersonic rotational flow with axial symmetry and supersonic rotational flow in a two-dimensional field was determined by use of the characteristics method. The system was applied to the study of external and internal flow for supersonic inlets with axial symmetry. For a circular conical inlet the shock that occurred at the lip of the inlet became stronger as it approached the axis of the inlet and became a normal shock at the axis. The region in which strong shock occurred increased with increase of the angle of internal cone at the lip of the inlet. For an inlet with a central body the method of characteristics was applied to the design of an internal channel shape that, theoretically, results in very efficient recompression in the inlet. It was shown that if an effuser is connected with the diffuser a body of revolution with very small shock-wave drag can be determined. (author).
Date: April 29, 1946
Creator: Ferri, Antonio
Partner: UNT Libraries Government Documents Department

Flutter and oscillating air-force calculations for an airfoil in two-dimensional supersonic flow

Description: A connected account is given of the Possio theory of non-stationary flow for small disturbances in a two-dimensional supersonic flow and of its application to the determination of the aerodynamic forces on an oscillating airfoil. Further application is made to the problem of wing flutter in the degrees of freedom - torsion, bending, and aileron rotations. Numerical tables for flutter calculations are provided for various values of the Mach number greater than unity. Results for bending-torsion wing flutter are shown in figures and are discussed. The static instabilities of divergence and aileron reversal are examined as is a one-degree-of-freedom case of torsional oscillatory instability.
Date: May 29, 1946
Creator: Garrick, I. E. & Rubinow, S. I.
Partner: UNT Libraries Government Documents Department

Tank investigation of a powered dynamic model of a large long-range flying boat

Description: "Principles for designing the optimum hull for a large long-range flying boat to meet the requirements of seaworthiness, minimum drag, and ability to take off and land at all operational gross loads were incorporated in a 1/12-size powered dynamic model of a four-engine transport flying boat having a design gross load of 165,000 pounds. These design principles included the selection of a moderate beam loading, ample forebody length, sufficient depth of step, and close adherence to the form of a streamline body. The aerodynamic and hydrodynamic characteristics of the model were investigated in Langley tank no. 1" (p. 1).
Date: November 29, 1946
Creator: Parkinson, John B.; Olson, Roland E. & Harr, Marvin I.
Partner: UNT Libraries Government Documents Department

Theoretical lift and drag of thin triangular wings at supersonic speeds

Description: "A method is derived for calculating the lift and the drag due to lift of point-forward triangular wings and a restricted series of sweptback wings at supersonic speeds. The elementary or "supersonic sources" solution of the linearized equation of motion is used to find the potential function of a line of doublets. The flow about the triangular flat plate is then obtained by a surface distribution of these doublet lines. The lift-curve slope of triangular wings is found to be a function of the ratio of the tangent of the apex angle to the tangent of the Mach angle" (p. 97).
Date: November 29, 1946
Creator: Brown, Clinton E.
Partner: UNT Libraries Government Documents Department

Buffeting of External Fuel Tanks at High Speeds on a Gruman F7F-3 Airplane

Description: Attempts were made to alleviate the buffeting of external fuel tanks mounted under the wings of a twin-engine Navy fighter airplane. The Mach number at which buffeting began was increased from 0,529 to 0.640 by streamlining the sway braces and by increasing the lateral rigidity of the sway brace system. Further increase of the Mach number, at which buffeting began to 0.725, was obtained by moving the external fuel tank to a position under the fuselage.
Date: January 29, 1947
Creator: Turner, Howard L.
Partner: UNT Libraries Government Documents Department

Flight Tests to Determine the Effect of Length of a Conical Windshield on the Drag of a Bluff Body at Supersonic Speeds

Description: Flight tests were conducted to determine the effect of length of a conical windshield on the drag of a bluff body moving at supersonic speeds. A comparison is made between results obtained and results of previous drag tests of body-windshield combinations.The effect of increasing the length of the windshield is discussed.
Date: January 29, 1947
Creator: Alexander, Sidney R. & Katz, Ellis
Partner: UNT Libraries Government Documents Department

The High-Speed Longitudinal Stability and Control of the Bell P-39N-1 Airplane as Calculated from Propeller-Off Tests of a 0.35-Scale Model

Description: This report presents the result of tests of a 0.35-scale model of the Bell P-39N-l airplane. Included are the longitudinal-stability and - control characteristics of the airplane as indicated by tests of the model equipped with each of two different sets of elevators. The results indicate good longitudinal stability and control throughout the speed range encounterable in flight. The variation of estimated stick force with speed was less when the model was equipped with elevators constructed to the theoretical design dimensions than when equipped with elevators as built to scale from measurements of the corresponding-parts of the actual airplane. The predicted stick forces required to produce the normal accelerations attainable in flight are within the limits specified by the Army Air Forces.
Date: January 29, 1947
Creator: Robinson, Robert C. & Perone, Angelo
Partner: UNT Libraries Government Documents Department

Effects of temperature distribution and elastic properties of materials on gas-turbine-disk stresses

Description: From Summary: "Calculations were made to determine the influence of changes in temperature distribution and in elastic material properties on calculated elastic stresses for a typical gas-turbine disk. Severe temperature gradients caused thermal stresses of sufficient magnitude to reduce the operating safety of the disk. Small temperature gradients were found to be desirable because they produced thermal stresses that subtracted from the centrifugal stresses in the region of the rim."
Date: March 29, 1947
Creator: Holms, Arthur G. & Faldetta, Richard D.
Partner: UNT Libraries Government Documents Department

Fuel Tests on an I-16 Jet-Propulsion Engine at Static Sea-Level Conditions

Description: Memorandum presenting an investigation of the effect of fuel composition and boiling point on the performance of the type of I-16 jet-propulsion engine. Testing occurred with 14 fuels embodying different types of hydrocarbon and with a range of boiling points. The results indicated that fuel composition and boiling range have a negligible effect on engine thrust, rotor speed, and gas temperatures for the principal types of hydrocarbon fuel when used for short periods of time.
Date: April 29, 1947
Creator: Bolz, Ray E. & Meigs, John B.
Partner: UNT Libraries Government Documents Department

Investigation of carbon deposition in an I-16 jet-propulsion engine at static sea-level conditions

Description: Report presenting a study of the effect of fuel properties on carbon deposition in jet-propulsion engine combustors using seven fuels: kerosene, Diesel fuel oil, toluene, xylene, 62-octane gasoline, a commercial solvent, and AN-F-32 (JP-1) in an I-16 engine at static sea-level conditions and constant rotor speed. Results regarding the reproducibility of data, reduced exhaust-jet-nozzle area, and fuel comparison are provided.
Date: April 29, 1947
Creator: Jonash, Edmund R.; Barnett, Henry C. & Stricker, Edward G.
Partner: UNT Libraries Government Documents Department

A Preliminary Study of Ram-Actuated Cooling Systems for Supersonic Aircraft

Description: An analysis has been made of the characteristics of several cooling cycles suitable for cockpit cooling of supersonic aircraft. All the cycles considered utilize the difference between dynamic and ambient static pressure to actuate the cooling system and require no additional power source. The results of the study indicate that as flight speeds become greater, increasingly complex systems are required to reduce the altitudes above approximately 35,000 feet, a system composed of an externally loaded expansion turbine in conjunction with a supersonic diffuser would maintain tolerable ventilating air temperature, at least up to a flight Mach number of 2. The most complex system considered,composed of compressor, intercooler, and expansion turbine with the intercooler cooling air decreased in temperature by expansion through an auxiliary turbine is capable of maintaining a ventilation air temperature less than ambient temperature up to a flight Mach number of 3.7.
Date: April 29, 1947
Creator: Stalder, Jackson R. & Wadleigh, Kenneth R.
Partner: UNT Libraries Government Documents Department

Free-flight investigation of control effectiveness of full-span 0.2-chord plain ailerons at high subsonic, transonic, and supersonic speeds to determine some effects of section thickness and wing sweepback

Description: Report discusses the development and testing of a rocket-propelled test vehicle to investigate aerodynamic control effectiveness at high subsonic, transonic, and supersonic speeds. Modifications to the section thickness and wing sweepback to improve performance are also described. A description of the vehicle, instrumentation, accuracy, and evaluation of testing results is included.
Date: May 29, 1947
Creator: Sandahl, Carl A. & Marino, Alfred A.
Partner: UNT Libraries Government Documents Department

An Investigation of the Aerodynamic Characteristics of an 0.08-Scale Model of the Chance Vought XF7U-1 Airplane in the Langley High-Speed 7- by 10-Foot Tunnel. Part III - Longitudinal-Control Characteristics TED No. NACA DE308, Part 3, Longitudinal-Control Characteristics, TED No. NACA DE308

Description: Tests have been conducted in the Langley high speed 7- by 10-foot tunnel over a Mach number range from 0.40 to 0.91 to determine the stability and control characteristics of an 0,08-scale model of the Chance Vought XF7U-1 airplane. The longitudinal-control characteristics of the complete model are presented in the present report with a limited analysis of the results.
Date: July 29, 1947
Creator: Kuhn, Richard E. & King, Thomas J., Jr.
Partner: UNT Libraries Government Documents Department

A unified theory of plastic buckling of columns and plates

Description: On the basis of modern plasticity considerations, a unified theory of plastic buckling applicable to both columns and plates has been developed. For uniform compression, the theory shows that long columns which bend without appreciable twisting require the tangent modulus and that long flanges which twist without appreciable bending require the secant modulus. Structures that both bend and twist when they buckle require a modulus which is a combination of the secant modulus and the tangent modulus.
Date: July 29, 1947
Creator: Stowell, Elbridge Z.
Partner: UNT Libraries Government Documents Department