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Calculations of Economy of 18-Cylinder Radial Aircraft Engine With Exhaust-Gas Turbine Geared to the Crankshaft at Cruising Speed

Description: Report presenting calculations based on dynamometer test-stand data on an 18-cylinder radial engine made to determine the improvement in fuel consumption that can be obtained by gearing an exhaust-gas turbine to the engine crankshaft in order to increase the engine shaft work.
Date: December 1945
Creator: Hannum, Richard W.
Partner: UNT Libraries Government Documents Department
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Wall interference in a two-dimensional-flow wind tunnel with consideration of the effect of compressibility

Description: Report presenting tunnel-wall corrections for an airfoil of finite thickness and camber in a two-dimensional-flow wind tunnel. The theory takes account of the effects of the wake of the airfoil and of the compressibility of the fluid and is based on the assumption that the chord of the airfoil is small in comparison with the height of the tunnel. The theoretical results are compared with the small amount of low-speed experimental data available and agreement is seen to be satisfactory, even for… more
Date: December 1944
Creator: Allen, H. Julian & Vincenti, Walter G.
Partner: UNT Libraries Government Documents Department
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The Conformal Transformation of an Airfoil Into a Straight Line and Its Application to the Inverse Problem of Airfoil Theory

Description: "A method of conformal transformation is developed that maps an airfoil into a straight line, the line being chosen as the extended chord line of the airfoil. The mapping is accomplished by operating directly with the airfoil ordinates. The absence of any preliminary transformation is found to shorten the work substantially over that of previous methods. Use is made of the superposition of solutions to obtain a rigorous counterpart of the approximate methods of thin-airfoils theory" (p. 1).
Date: December 1944
Creator: Mutterperl, William
Partner: UNT Libraries Government Documents Department
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Aerodynamic Tests of a Full-Scale TBF-1 Aileron Installation in the Langley 16-Foot High-Speed Tunnel

Description: "This report describes tests in the Langley 16-foot high-speed tunnel to determine whether these failures could be attributed to changes in the aerodynamic characteristics of the ailerons at high speeds" (p. 1).
Date: December 1944
Creator: Becker, John V. & Korycinski, Peter F.
Partner: UNT Libraries Government Documents Department
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Fatigue Strength and Related Characteristics of Aircraft Joints 1: Comparison of Spot-Weld and Rivet Patterns in 24S-T Alclad and 75S-T Alclad

Description: Report contains detailed results of a number of fatigue tests on spot-welded joints in aluminum alloys. The tests described include: (1) fatigue tests on spot-welded lap joints in sheets of unequal thickness of alclad 24s-t. These tests indicate that the fatigue strength of a spot-welded joint in sheets of two different gages is slightly higher than that of a similar joint in two sheets of the thinner gage but definitely lower than that of a similar joint in two sheets of the thicker gage. (2) … more
Date: December 1944
Creator: Russell, H. W.; Jackson, L. R.; Grover, H. J. & Beaver, W. W.
Partner: UNT Libraries Government Documents Department
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Effect of Propeller-Axis Angle of Attack on Thrust Distribution Over the Propeller Disk in Relation to Wake-Survey Measurement of Thrust

Description: "Tests were made to investigate the variation of thrust distribution over the propeller disk with angle of pitch of the propeller thrust axis and to determine the disposition and the minimum number of rakes necessary to measure the propeller thrust. The tests were made at a low Mach number for a low and a high blade angle with the propeller operating at three small angles of pitch, and some of the tests were repeated at a higher Mach number. The data obtained show that, for small angles of pitc… more
Date: December 1945
Creator: Pendley, Robert E.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of an NACA 23012 Airfoil With a 0.30-Airfoil-Chord Double Slotted Flap

Description: Report discusses the results of testing of flap position and deflection on the aerodynamic characteristics of a NACA 23012 airfoil with a double slotted flap with a chord 30 percent of the airfoil chord. The maximum lift coefficient, profile-drag coefficients, pitching-moment coefficients, lift, and drag are provided at several positions of the flap. The results were also compared to previous testing on several flap configurations.
Date: December 1943
Creator: Purser, Paul E.; Fischel, Jack & Riebe, John M.
Partner: UNT Libraries Government Documents Department
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Pressure distribution over an airfoil with a balanced split flap

Description: Report presenting a pressure-distribution investigation conducted in the 4- by 6-foot vertical wind tunnel to determine the air loads on an airfoil with a 22.1-percent-chord balanced split flap. Results regarding section pressure distribution and aerodynamic section coefficients are provided.
Date: December 1941
Creator: Lowry, John G.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of a Spoiler-Slot Aileron on an NACA 23012 Airfoil With a Full-Span Fowler Flap

Description: Report presenting an investigation of a spoiler-slot aileron on an NACA 23012 airfoil with a full-span 30-percent-chord Fowler flap. The static rolling, yawing, and hinge moments were determined for several angles of attack and flap deflections. The ineffective region could be eliminated by a provision in the aileron linkage that would automatically uprig the ailerons as the flap is deflected.
Date: December 1941
Creator: Rogallo, F. M. & Spano, Bartholomew S.
Partner: UNT Libraries Government Documents Department
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Wind-tunnel investigation of 20-percent-chord plain and Frise ailerons on an NACA 23012 airfoil

Description: Report presenting an investigation of several modifications of 20-percent-chord plain and Frise ailerons on an NACA 23012 airfoil in the 7- by 10-foot wind tunnel. Static rolling, yawing, and hinge moments were determined for several angles of attack.
Date: December 1941
Creator: Purser, Paul E.
Partner: UNT Libraries Government Documents Department
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Characteristics of beveled-trailing-edge elevators on a typical pursuit fuselage at altitudes simulating-normal flight and spin conditions

Description: Report presenting lift and elevator hinge-moment characteristics were measured on horizontal tail provided with elevators having three different beveled trailing edges. Results regarding fuselage alone and fuselage interference, lift characteristics of fuselage-tail combination, elevator hinge-moment characteristics, drag, and comparison with data from two-dimensional-flow tests are provided.
Date: December 1942
Creator: Gillis, Clarence L.
Partner: UNT Libraries Government Documents Department
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Some Systematic Model Experiments of the Bow-Spray Characteristics of Flying-Boat Hulls Operating at Low Speeds in Waves

Description: Report discusses the results of testing on several models of flying boats, the XPB2M-1, the XPBB-1, the JRM-1, and 11 other models to determine the effect of bow form on the amount of spray thrown onto the windshield of a flying boat in rough water. Several recommendations for reducing the height and volume of spray are provided. Any change in the hull form that softens the impact between the hull and waves seems to reduce the spray.
Date: December 1943
Creator: Locke, F. W. S., Jr.
Partner: UNT Libraries Government Documents Department
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The Effect of Various Surface Conditions on Press Fits of Steel Bushings and 17S-T Aluminum-Alloy Fittings

Description: Report presenting testing of specimens of 17S-T aluminum-alloy fittings with pressed-in steel bushings for various surface conditions. The surface conditions tested included bare surfaces, aonidcal coating and steel cadmium-plate, and one surface treated and the other bare, both without lubrication and with Gredag No. 83 as a lubricant. The calculated coefficients of friction for the various press fits for the investigation ranged from 0.33 for the unlubricated contact of bare steel and aluminu… more
Date: December 1942
Creator: Hartmann, E. C. & Reedy, J. F.
Partner: UNT Libraries Government Documents Department
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An Investigation of Aircraft Heaters 6: Heat Transfer Equations for the Single Pass Longitudinal Exchanger

Description: Report presenting an analysis of parallel flow and contraflow single pass heat exchangers, together with charts which allow the direct evaluation of the thermal performance of the units without recourse to trail-and-error techniques. The use of equations and charts is illustrated by several examples.
Date: December 1942
Creator: Martinelli, R. C.; Morrin, E. H. & Boelter, L. M. K.
Partner: UNT Libraries Government Documents Department
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A Preliminary Investigation of the Characteristics of Air Scoops on a Fuselage

Description: Report presenting an investigation of the characteristics of air scoops in the NACA propeller-research tunnel. The investigation showed that, at inlet-velocity ratios equal to or greater than 0.3, scoops in a forward position on the fuselage gave total pressures in the inlet nearly equal to free-stream total pressure.
Date: December 1942
Creator: Bell, E. Barton & DeKoster, Lucas J.
Partner: UNT Libraries Government Documents Department
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An Investigation of Aircraft Heaters 5: Theory and Use of Heat Meters for the Measurement of Rates of Heat Transfer Which Are Independent of Time

Description: Report presenting a description of a meter which will measure the heat flowing through surfaces. Its operation is based on the measurement of the temperature decrease through a fixed thermal resistance. Only the case of heat flow independent of time is discussed in this particular report.
Date: December 1942
Creator: Martinelli, R. C.; Morrin, E. H. & Boelter, L. M. K.
Partner: UNT Libraries Government Documents Department
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The effect of concentrated loads on flexible rings in circular shells

Description: Report presenting a method of making strain measurements on a series of circular cylinders with reinforcing rings, subjected to concentrated loads, in which the bending stiffness of the rings was varied systematically over a wide range. Results regarding the general remarks, bending-moment coefficient, and skin shear coefficients are provided.
Date: December 1945
Creator: Kuhn, Paul; Duberg, John E. & Griffith, George E.
Partner: UNT Libraries Government Documents Department
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A Flight Investigation of Internally Balanced Sealed Ailerons

Description: "Flight tests were made of a type of internally balanced sealed ailerons installed on a Ryan ST airplane. Aileron effectiveness and stick forces were measured at various airspeeds under NACA recording instruments. For comparison, the aileron characteristics were also determined without the internal balance and seals" (p. 1).
Date: December 1941
Creator: Williams, W. C. & Kleckner, H. F.
Partner: UNT Libraries Government Documents Department
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Strength Tests of Thin-Wall Truncated Cones of Circular Section

Description: "The ends of thin-wall truncated cones of circular section were clamped to rigid bulkheads and the cones subjected to strength tests. The results from torsion tests of five, compression tests of three, and tests in combined transverse shear and bending of 18 truncated cones are given herein. The results of the tests are correlated with the previously published results of corresponding tests of circular cylinders and are presented in charts suitable for use in design" (p. 1).
Date: December 1942
Creator: Lundquist, Eugene E. & Schuette, Evan H.
Partner: UNT Libraries Government Documents Department
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Effect of Changes in Aspect Ratio, Side Area, Flight-Path Angle, and Normal Acceleration on Lateral Stability

Description: Report presenting computations made to determine the effect of changes in wing aspect ratio, additional side area, flight-path angle, and normal acceleration on the relation between the fin area and the dihedral angle required for spiral and for oscillatory lateral stability for a hypothetical airplane of the pursuit or fighter categories. The diagrams indicate that the effect of wing aspect ratio on lateral stability is small.
Date: December 1942
Creator: Bamber, M. J.
Partner: UNT Libraries Government Documents Department
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Propellers in yaw

Description: Report presenting the propeller forces due to an angular velocity of pitch, which are analyzed and shown to be very small for the pitching velocities that may actually be realized in maneuvers, with the exception of the spin. A dual-rotating propeller in yaw was found to develop up to one-third more side force than a single-rotating propeller.
Date: December 1943
Creator: Ribner, Herbert S.
Partner: UNT Libraries Government Documents Department
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Calculations of the Performance of a Compression-Ignition Engine-Compressor Turbine Combination 1: Performance of a Highly Supercharged Compression-Ignition Engine

Description: From Summary: "Small high-speed single-cylinder compression-ignition engines were tested to determine their performance characteristics under high supercharging. Calculations were made on the energy available in the exhaust gas of the compression-ignition engines. The maximum power at any given maximum cylinder pressure was obtained when the compression pressure was equal to the maximum cylinder pressure. Constant-pressure combustion was found possible at an engine speed of 2200 rpm."
Date: December 1945
Creator: Sanders, J. C. & Mendelson, Alexander
Partner: UNT Libraries Government Documents Department
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Knock-limited power outputs from a CFR engine using internal coolants 1: monomethylamine and dimethylamine

Description: Report presenting an investigation to determine the knock-limited power obtainable by injecting water solutions of monomethylamine and dimethylamine as internal coolants into a CFR engine using AN-F-28, Amendment-2, fuel.
Date: December 1944
Creator: Bellman, Donald R.; Moeckel, W. E. & Evvard, John C.
Partner: UNT Libraries Government Documents Department
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