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An Analytical and Experimental Study of the Effect of Periodic Blade Twist on the Thrust, Torque, and Flapping Motion of an Autogiro Rotor

Description: From Summary: "An analysis is made of the influence on autogiro rotor characteristics of a periodic blade twist that varies with the azimuth position of the rotor blade and the results are compared with experimental data. The analysis expresses the influence of this type of twist upon the thrust, torque, and flapping motion of the rotor. The check against experimental data shows that the periodic twist has a pronounced influence on the flapping motion and that this influence is accurately predi… more
Date: January 28, 1937
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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The influence of wing setting on the wing load and rotor speed of a PCA-2 autogiro as determined in flight

Description: Flight tests were made on PCA-2 autogiro with wing settings of 2.2 degrees, 0.9 degrees, and -0.5 degrees. The wing load and rotor speed were measured in steady glides. The results obtained show that a wide variation in rotor speed as a function of air speed can be obtained by a suitable adjustment of the wing setting; that by decreasing the wing setting the upper safe flying speed, determined by the decrease is rotor speed, is greatly increased; and that the interference of the wing on the rot… more
Date: December 28, 1934
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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Lift and drag characteristics and gliding performance of an autogiro as determined in flight

Description: From Summary: "This report presents the results of flight test of the Pitcairn "PCA-2" autogiro. Lift and drag coefficients with the propeller stopped have been determined over approximately a 90 degree range of angles of attack. Based on the sum of fixed-wing and swept-disk areas, the maximum lift coefficient is 0.895, the minimum drag coefficient with propeller stopped is 0.015, and the maximum l/d with propeller stopped is 4.8. Lift coefficients were found also with the propeller delivering … more
Date: May 2, 1932
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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Simplified aerodynamic analysis of the cyclogiro rotating wing system

Description: A simplified aerodynamic theory of the cyclogiro rotating wing is presented herein. In addition, examples have been calculated showing the effect on the rotor characteristics of varying the design parameters of the rotor. A performance prediction, on the basis of the theory here developed, is appended, showing the performance to be expected of a machine employing this system of sustentation. The aerodynamic principles of the cyclogiro are sound; hovering flight, vertical climb, and a reasonable… more
Date: August 1933
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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A study of autogiro rotor-blade oscillations in the plane of the rotor disk

Description: An analysis of the factors governing the oscillation of an autogiro rotor blade in the plane of the rotor disk showed that the contribution of the air forces to the resultant motion was small and that the oscillation is essentially a direct effect of the rotor-blade flapping motion. A comparison of calculated oscillations with those measured in flight on three different rotors disclosed that the calculations gave satisfactory agreement with experiment. The calculated air forces on the rotor bla… more
Date: September 1936
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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Torsion in box wings

Description: From Summary: "Logical analysis of a box wing necessitates the allowance for the contribution of the drag spars to the torsional strength of the structure. A rigorous analysis is available in the use of the Method of Least Work. The best logical method of analysis is that applying Prandtl's Membrane Analogy. The results so obtained vary by a negligible amount from those obtained by the rigorous method."
Date: February 1931
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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Wing pressure distribution and rotor-blade motion of an autogiro as determined in flight

Description: From Summary: "This report presents the results of tests in which the pressure distribution over the fixed wing of an autogiro was determined in both steady and accelerated flight. In the steady-flight condition, the rotor-blade motion was also measured. These data show that in steady flight the rotor speed as a function of the air speed is largely affected by the variation of the division of load between the rotor and the wing; as the load on the wing increases, the rotor speed decreases."
Date: July 31, 1933
Creator: Wheatley, John B.
Item Type: Refine your search to only Report
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Analysis and Model Tests of Autogiro Jump Take-Off

Description: From Introduction: "The possibilities of the jump take-off have been established by some full-scale experiments. It is the purpose of this paper to study the factors that govern the jump take-off in its simplest form and to present the results of model tests in which the effect of differences in the rotor parameters was determined."
Date: October 1936
Creator: Wheatley, John B. & Bioletti, Carlton
Item Type: Refine your search to only Report
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Wind-tunnel tests of 10-foot-diameter autogiro rotors

Description: Report presents the results of a series of 10-foot-diameter autogiro rotor models tested in the NACA 20-foot wind tunnel. Four of the models differed only in the airfoil sections of the blades, the sections used being the NACA 0012, 0018, 4412, and 4418. Three additional models employing the NACA 0012 section were tested, in which a varying portion of the blade near the hub was replaced by a streamline tube with a chord of about one-fourth the blade chord.
Date: 1936
Creator: Wheatley, John B. & Bioletti, Carlton
Item Type: Refine your search to only Report
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Wind-tunnel tests of a 10-foot-diameter gyroplane rotor

Description: This report presents the results of wind-tunnel tests on a model gyroplane rotor 10 feet in diameter. The rotor blades had zero sweepback and zero offset; the hub contained a feathering mechanism that provided control of the rotor rolling moment, but not of the pitching moment. The rotor was tested with 4 blades and with 2 blades. The entire useful range of pitch settings and tip-speed ratios was investigated including the phase of operation in which the rotor turned very slowly, or idled.
Date: 1935
Creator: Wheatley, John B. & Bioletti, Carlton
Item Type: Refine your search to only Report
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Full-scale wind-tunnel tests of a PCA-2 autogiro rotor

Description: This report presents the results of force tests on and air-flow surveys near PCA-2 autogiro rotor in the NACA full-scale wind tunnel. The force tests were made at three pitch settings and several rotor speeds; the effect of fairing protuberances on the rotor blade was determined. Induced downwash and yaw angles were determined at low tip-speed ratios in a plane 1 1/2 feet above the path of the blade tips. The results show that the maximum l/d of the rotor cannot be appreciably increased by incr… more
Date: October 12, 1934
Creator: Wheatley, John B. & Hood, Manley J.
Item Type: Refine your search to only Report
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Wind-tunnel tests of a cyclogiro rotor

Description: During an extensive study of all types of rotating wings, the NACA examined the cyclogiro rotor and made an aerodynamic analysis of that system (reference 1). The examination disclosed that such a machine had sufficient promise to justify an experimental investigation; a model with a diameter and span of 8 feet was therefore constructed and tested in the 20-foot wind tunnel during 1934. The experimental work included tests of the effect of the motion upon the rotor forces during the static-lift… more
Date: May 1935
Creator: Wheatley, John B. & Windler, Ray
Item Type: Refine your search to only Report
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Wing-Fuselage Interference, Tail Buffeting, and Air Flow About the Tail of a Low-Wing Monoplane

Description: "This report presents the results of wind tunnel tests on a Mcdonnell Douglas airplane to determine the wing-fuselage interference of a low-wing monoplane. The tests included a study of tail buffeting and the air flow in the region of the tail. The airplane was tested with and without the propeller slipstream, both in the original condition and with several devices designed to reduce or eliminate tail buffeting. The devices used were wing-fuselage fillets, a NACA cowling, reflexed trailing edge… more
Date: December 13, 1933
Creator: White, James A. & Hood, Manley J.
Item Type: Refine your search to only Report
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Charts for Calculating the Performance of Airplanes Having Constant-Speed Propellers

Description: "Charts are presented for determining the performance of airplanes having variable-pitch propellers, the pitch of which is assumed to be adjusted to maintain constant speed for all rates of flight. The charts are based on the general performance equations developed by Oswald in reference 1, and are used in a similar manner. Examples applying the charts to airplanes having both supercharged and unsupercharged engines are included" (p. 1).
Date: September 1936
Creator: White, Roland J. & Martin, Victor J.
Item Type: Refine your search to only Report
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Strength of Welded Joints in Tubular Members for Aircraft

Description: "The object of this investigation is to make available to the aircraft industry authoritative information on the strength, weight, and cost of a number of types of welded joints. This information will, also, assist the aeronautics branch in its work of licensing planes by providing data from which the strength of a given joint may be estimated. As very little material on the strength of aircraft welds has been published, it is believed that such tests made by a disinterested governmental labora… more
Date: February 6, 1930
Creator: Whittemore, H. L. & Brueggeman, W. C.
Item Type: Refine your search to only Report
open access

Contribution to the Mutual Interference of Wing and Propeller

Description: "The change of induced wing drag due to the field of flow of the propeller was analyzed quantitatively. The field of flow of the propeller is represented by a uniform distribution of sinks over the propeller disk area, whose strength is determined by the increase in speed in the slipstream. The superposition of this sink flow on the basic flow reproduces the actual field of flow outside of the slipstream with close approximation" (p. 1).
Date: September 1934
Creator: Wieselsberger, C.
Item Type: Refine your search to only Report
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Pressure Drop in Tubing in Aircraft Instrument Installations

Description: "The theoretical basis of calculation of pressure drop in tubing is reviewed briefly. The effect of pressure drop in connecting tubing upon the operation and indication of aircraft instruments is discussed. Approximate equations are developed, and charts and tables based upon them are presented for use in designing installations of altimeters, air-speed indicators, rate-of-climb indicators, and air-driven gyroscopic instruments" (p. 1).
Date: February 1937
Creator: Wildhack, W. A.
Item Type: Refine your search to only Report
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Corrugated Metal Diaphragms for Aircraft Pressure-Measuring Instruments

Description: Note presenting a description of a large number of corrugated diaphragms of beryllium copper, phosphor bronze, and Z-nickel with geometrically similar outlines but various diameters and thicknesses were formed by hydraulic pressing. The apparatus and technique used in the manufacture, testing, and heat treatment are described. Results regarding pressure-deflection curves, load limit, effect of center reinforcing, snap-action diaphragms, deflection traverse, thickness variations, and concentrate… more
Date: November 1939
Creator: Wildhack, W. A. & Goerke, V. H.
Item Type: Refine your search to only Report
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Mercerization of Cotton for Strength With Special Reference to Aircraft Cloth

Description: The object of the present investigation was to determine the conditions for mercerizing cotton yarn to obtain the maximum strength for a given weight. Apparatus for controlling the variables was built and yarns were mercerized with it under systematically varied conditions of tension, time, temperature, and concentration of caustic soda. The strongest conclusion to be drawn from this work is that the strongest mercerized yarn of a given count from a given quality of cotton is obtained under cer… more
Date: February 1933
Creator: Wilkie, J. B.
Item Type: Refine your search to only Report
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Drag Tests of 4/9-Scale Model Engine Nacelles With Various Cowlings

Description: "Results are given of drag tests of 4/9-scale model radial air-cooled engine nacelles made as a part of a general investigation of wing-nacelle-propeller interference. A small nacelle of the type commonly used with exposed engine cylinders was tested with various forms of cowling over the cylinders. The effects of cowling-ring position and of angle of ring chord to the thrust line were investigated. An N.A.C.A. cowled nacelle and a smooth body were also tested. The results are given at 50, 75, … more
Date: October 1932
Creator: Windler, Ray
Item Type: Refine your search to only Report
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The Effect of Propellers and Nacelles on the Landing Speeds of Tractor Monoplanes

Description: "This paper reports wind-tunnel tests giving the lift coefficients of large-scale wing-nacelle combinations both with and without the propeller. The tests were made to show the effect of nacelles, and idling and stopped propellers on the landing speeds of tractor monoplanes. Four types of nacelles with various cowlings were used in numerous positions with respect to both a Clark Y and a thick airfoil. The effect of both the idling and stopped propeller on lift, and consequently on landing speed… more
Date: May 1932
Creator: Windler, Ray
Item Type: Refine your search to only Report
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Tests of a Wing-Nacelle-Propeller Combination at Several Pitch Settings Up to 42 Degrees

Description: This report presents the results of tests of a 4-foot model of Navy propeller No. 4412 in conjunction with an NACA cowled nacelle mounted ahead of a thick wing in the 20-foot propeller-research tunnel. A range of propeller pitches from 17 degrees to 42 degrees at 0.75r was covered, and for this propeller the efficiency reached a maximum at a pitch setting of 27 degrees; at high pitches the efficiencies were slightly lower. The corrected propulsive efficiency is shown to be independent of the an… more
Date: November 12, 1935
Creator: Windler, Ray
Item Type: Refine your search to only Report
open access

Contribution to the Theory of the Heated Duct Radiator

Description: A method is developed with no neglect of certain factors in mass flow of air and in the drag of the heated radiator, i.e., one under actual operating conditions, as compared with the corresponding values in the cold state, may be simply computed. Although a symmetrical duct radiator has been used to bring out the flow relations, the results apply equally as well to the unsymmetrical radiator shapes usual in airplane construction.
Date: April 1939
Creator: Winter, H.
Item Type: Refine your search to only Report
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