Technical Report Archive & Image Library (TRAIL) - 417 Matching Results

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Noise From Propellers With Symmetrical Sections at Zero Blade Angle

Description: "A theory has been deduced for the "rotation noise" from a propeller with blades of symmetrical section about the chord line and set at zero blade angle. Owing to the limitation of the theory, the equations give without appreciable error only the sound pressure for cases where the wave lengths are large compared with the blade lengths. With the aid of experimental data obtained from a two-blade arrangement, an empirical relation was introduced that permitted calculation of higher harmonics" (p.… more
Date: July 1937
Creator: Deming, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Noise From Propellers With Symmetrical Sections at Zero Blade Angle, 2

Description: "In a previous paper (Technical Note No. 605), a theory was developed that required an empirical relation to calculate sound pressures for the higher harmonics. Further investigation indicated that the modified theory agrees with experiment and that the empirical relation was due to an interference phenomenon peculiar to the test arrangement used. Comparison is made between the test results for a two-blade arrangement and the theory" (p. 1).
Date: December 1938
Creator: Deming, A. F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The 6-Foot-4-Inch Wind Tunnel at the Washington Navy Yard

Description: Report discussing the 6-foot-4-inch wind tunnel and its auxiliary equipment has proven itself capable of continuous and reliable output of data. The real value of the tunnel will increase as experience is gained in checking the observed tunnel performance against full-scale performance. Such has been the case of the 8- by 8-foot tunnel, and for that reason the comparison in the calibration tests have been presented.
Date: August 1935
Creator: Desmond, G. L. & McCrary, J. A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Considerations affecting the additional weight required in mass balance of ailerons

Description: "This paper is essentially a consideration of mass balance of ailerons from a preliminary design standpoint, in which the extra weight of the mass counterbalance is the most important phase of the problem. Equations are developed for the required balance weight for a simple aileron and this weight is correlated with the mass-balance coefficient. It is concluded the location of the c.g. of the basic aileron is of paramount importance and that complete mass balance imposes no great weight penalty… more
Date: August 1937
Creator: Diehl, W. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some fundamental considerations in regard to the use of power in landing an airplane

Description: From Summary: "This note is concerned with the effect of power on landing speed and apparent maximum lift coefficient. It is shown that when secondary effects are neglected, the maximum available increase in lift due to power is equal to the thrust being developed. If the increase in lift due to power is expressed in coefficient form, very high values may be shown under conditions which, on analysis, are found to be wholly impracticable in flight."
Date: March 1939
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A study of flying-boat take-off

Description: It is shown that the normal resistance curve for a flying boat may be approximated by two straight lines. The equations for take-off distance and time, derived from this approximation, are applied to a series of flying boats and the resulting factors are plotted in non dimensional form in a series of charts. Take-off performances from the charts are shown to be in good agreement with step-by-step integrations. Some applications of the charts to the solution of general design problems are includ… more
Date: April 1938
Creator: Diehl, Walter S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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An Experimental Investigation of the Normal Acceleration of an Airplane Model in a Gust

Description: Note presenting an investigation in the gust tunnel to determine the influence of airplane wing loading, forward velocity, wing plan form, and the fuselage on the reaction of the airplane to a known gust. Tests were made for four values of gust velocity and for two gust gradients, specifically the sharp-edge gust and a gust rising linearly to full strength in a distance of several chord lengths.
Date: May 1939
Creator: Donely, Philip
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Forces and Moments on Airplane Engine Mounts

Description: "A resume of the equations and formulas for the forces and moments on an aircraft-engine mount is presented. In addition, available experimental data have been included to permit the computation of these forces and moments. A sample calculation is made and compared with present design conditions for engine mounts" (p. 1).
Date: December 1936
Creator: Donely, Philip
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Flight and wind-tunnel tests of an XBM-1 dive bomber

Description: From Summary: "Results are given of pressure-distribution measurements made in flight over the right wing cellule and the right half of the horizontal tail surfaces of a dive-bombing biplane. Simultaneous measurements were also taken of the air speed, control-surface positions, control forces, and normal accelerations during various abrupt maneuvers in vertical plane. These maneuvers consisted of push-downs and pull-ups from level flight, dives and dive pull-ups from inverted flight. Besides th… more
Date: April 1938
Creator: Donely, Philip & Pearson, Henry A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Tests in the gust tunnel of a model of the XBM-1 airplane

Description: Report presenting testing of a dynamically scaled model of a Navy XBM-1 biplane in the gust tunnel to provide data for use in determining the structure of atmospheric gusts from measurements of the motions of the full-scale airplane in rough air. Records for two flights for several gradients were evaluated to give histories of events during passage through the gust.
Date: October 1939
Creator: Donely, Philip & Shufflebarger, C. C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The sonic altimeter for aircraft

Description: Discussed here are results already achieved with sonic altimeters in light of the theoretical possibilities of such instruments. From the information gained in this investigation, a procedure is outlined to determine whether or not a further development program is justified by the value of the sonic altimeter as an aircraft instrument. The information available in the literature is reviewed and condensed into a summary of sonic altimeter developments. Various methods of receiving the echo and t… more
Date: August 1937
Creator: Draper, C. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Stress concentration around an open circular hole in a plate subjected to bending normal to the plane of the plate

Description: "An aluminum-alloy plate containing an open circular hole of diameter large compared with the thickness of the plate was subjected to bending forces normal to the plane of the plate. Deflection and strain measurements were taken for two different loads. Stress concentrations occurred at the edge of the hole and the maximum stresses were tangential to the hole at the ends of the transverse diameter. The maximum stress at the edge of the hole was 1.59 times the computed stress on the net section … more
Date: December 1939
Creator: Dumont, C.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The lateral instability of deep rectangular beams

Description: "Experimental and analytical studies were made of solid and hollow deep rectangular beams to study their lateral instability under various conditions of loading and restraint. The tests were made on bars and tubes of 17ST aluminum alloy. Failure by lateral buckling occurred only in tests on the solid beams. It was found that, within the elastic range, the test results were in agreement with the classical theory for the lateral buckling of deep beams as given by Prandtl, Mitchell, and Timoshenko… more
Date: May 1937
Creator: Dumont, C. & Hill, H. N.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of an N.A.C.A. 23021 Airfoil With Two Arrangements of a 40-Percent-Chord Slotted Flap

Description: Note presenting an investigation in the 7- by 10-foot wind tunnel of an NACA 23021 airfoil with two arrangements of a 40-percent-chord slotted flap. The effect of slot shape, flap position, and flap deflection on the section aerodynamic characteristics was determined. Results regarding coefficients, precision, plain airfoils, and slotted-flap arrangements are provided.
Date: September 1939
Creator: Duschik, Frank
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Calculations of the Effect of Wing Twist on the Air Forces Acting on a Monoplane Wing

Description: "A method is presented for calculating the aerodynamic forces on a moncylane wing, taking into account the elastic twisting of the wing due to these forces. The lift distribution along the span is calculated by the formulas of Amstutz as a function of the geometrical characteristics of the wing and of the twist at stations 60 and 90 percent of the semispan. The twist for a given lift distribution is calculated by means of influence lines" (p. 1).
Date: March 1935
Creator: Dätwyler, G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Air-Entry Angle on Performance of a 2-Stroke-Cycle Compression-Ignition Engine

Description: "An investigation was made to determine the effect of variations in the horizontal and vertical air-entry angles on the performance characteristics of a single-cylinder 2-stroke-cycle compression-ignition test engine. Performance data were obtained over a wide range of engine speed, scavenging pressure, fuel quantity, and injection advance angle with the optimum guide vanes. Friction and blower-power curves are included for calculating the indicated and net performances" (p. 1).
Date: August 1937
Creator: Earle, Sherod L. & Dutee, Francis J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Physical Properties of Synthetic Resin Materials

Description: "A study was made to determine the physical properties of synthetic resins having paper, canvas, and linen reinforcements, and of laminated wood impregnated with a resin varnish. The results show that commercial resins have moduli of elasticity that are too low for structural considerations. Nevertheless, there do exist plastics that have favorable mechanical properties and, with further development, it should be possible to produce resin products that compare favorably with the light-metal all… more
Date: March 1939
Creator: Fishbein, Meyer
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Effect on Engine Performance of Change in Jacket-Water Outlet Temperature

Description: Tests made on a Curtiss D-12 engine in the Altitude Laboratory at the Bureau of Standards show the following effects on engine performance of change in jacket-water outlet temperature: 1) Friction at all altitudes is a linear function of the jacket-water temperature, decreasing with increasing temperature. 2) The brake horsepower below an altitude of about 9,000 feet decreases, and at higher altitudes increases, with jacket-water temperature. 3) The brake specific fuel consumption tends to decr… more
Date: November 1933
Creator: Garlock, E. A. & Ellis, Greer
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Wind-tunnel tests of a Clark Y wing with "Maxwell" leading-edge slots

Description: Aerodynamic force tests of a Clark Y wing equipped with "Maxwell" type leading-edge slots were conducted in the N.A.C.A. 7- by 10-foot tunnel to ascertain the aerodynamic characteristics, which involved the determination of the best slot-gap opening, the effects of slat width, and the effect of a trailing-edge flap. The Maxwell wing with a wide-chord slat (0.30 c(sub w)) and with a 0.211 c(sub w) split flap deflected 60 degrees had a C(sub L sub max) of 2.53 or about twice that of the plain win… more
Date: April 1937
Creator: Gauvain, William E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Prevention of the Ice Hazard on Airplanes

Description: A review of various methods to prevent ice formation and adhesion to aircraft surfaces is given. It was concluded that the adhesion of ice to a surface may be reduced somewhat by the application of certain waxes and varnishes. In the experiments described, the varnishes containing calcium stearate and calcium oleate gave the best results. In wind tunnel tests, the adhesion was further reduced by the application of these waxes and varnishes to a thin, heat insulating layer of rubber.
Date: July 1930
Creator: Geer, William C. & Scott, Merit
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Orifice Length-Diameter Ratio on Spray Characteristics

Description: "The effect of variations of orifice length to diameter ratio on spray characteristics was determined for a 0.014-inch and a 0.040-inch orifice for ratio of 0.5 to 4.0. The nozzles containing the orifices were mounted in an injection valve and tested with a plan stem and with a helically grooved stem. The injection pressure was varied from 4000 to 8000 pounds per square inch. The air density into which the fuel was sprayed was varied from the density obtained with a pressure of 60 pounds per sq… more
Date: October 1930
Creator: Gelalles, A. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Some effects of air and fuel oil temperatures on spray penetration and dispersion

Description: Presented here are experimental results obtained from a brief investigation of the appearance, penetration, and dispersion of oil sprays injected into a chamber of highly heated air at atmospheric pressure. The development of single sprays injected into a chamber containing air at room temperature and at high temperature was recorded by spray photography equipment. A comparison of spray records showed that with the air at the higher temperature, the spray assumed the appearance of thin, transpa… more
Date: May 1930
Creator: Gelalles, A. G.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Effect of Orifice Length-Diameter Ratio on the Coefficient of Discharge of Fuel-Injection Nozzles

Description: The variation of the coefficient of discharge with the length-diameter ratio of the orifice was determined for nozzles having single orifice 0.008 and 0.020 inch in diameter. Ratios from 0.5 to 10 were investigated at injection pressures from 500 to 5,000 pounds per square inch. The tests showed that, within the error of the observation, the coefficients were the same whether the nozzles were assembled at the end of a constant tube or in an automatic injection valve having a plain stem.
Date: March 1931
Creator: Gelalles, A. G. & Marsh, E. T.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Influence of Fuel-Oil Temperature on the Combustion in a Prechamber Compression-Ignition Engine

Description: Note presenting the influence of fuel-oil temperature on combustion as investigated by injecting the fuel into the prechamber of a single-cylinder, 4-stroke-cycle, water-cooled, compression-ignition engine operating at 1500 rpm and at a compression ratio of 13.5. The results showed that heating the fuel oil to 750 degrees Fahrenheit increased the injection period, changed the rate of injection, and eliminated the spray cone.
Date: April 1936
Creator: Gerrish, Harold C. & Ayer, Bruce E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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