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Internal-Flow Systems for Aircraft

Description: "An investigation has been made to determine efficient arrangements for an internal-flow system of an aircraft when such a system operates by itself or in combination with other flow systems. The investigation included a theoretical treatment of a problem and tests in the NACA 5-foot vertical wind tunnel of inlet and outlet openings in a flat plate and in a wing. When an internal-flow system tends to decrease the final velocity of it's wake, the results showed that it should be arranged in seri… more
Date: October 1940
Creator: Rogallo, F. M.
Item Type: Refine your search to only Report
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The Development of Electrical Strain Gages

Description: "The design, construction, and properties of an electrical-resistance strain gage consisting of fine wires molded in a laminated plastic are described. The properties of such gages are discussed and also the problems of molding of wires in plastic materials, temperature compensation, and cementing and removal of the gages. Further work to be carried out on the strain gage, together with instrument problems, is discussed" (p. 1).
Date: January 1940
Creator: de Forest, A. V. & Leaderman, H.
Item Type: Refine your search to only Report
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Tests of a gust-alleviating flap in the gust tunnel

Description: "Tests were made to determine the effectiveness of a long-period dynamically overbalanced flap in reducing airplane accelerations due to atmospheric gusts. For two gust shapes, one gust velocity, one forward velocity, and one wing loading, a series of flights was made with the flap locked and was then repeated with the flap free to operate. The records were evaluated by routine methods. The results indicate that the flap reduced the maximum acceleration increment 39 percent for a severe gust bu… more
Date: January 1940
Creator: Donely, Philip & Shufflebarger, C. C.
Item Type: Refine your search to only Report
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Tensile and Pack Compressive Tests of Some Sheets of Aluminum Alloy, 1025 Carbon Steel, and Chromium-Nickel Steel

Description: "Tensile and compressive stress-strain curves, stress-deviation curves, and secant modulus-stress curves are given for longitudinal and transverse specimens of 17S-T, 24S-T, and 24S-RT aluminum-alloy sheet in thicknesses from 0.032 to 0.081 inch, 1025 carbon steel sheet in thicknesses of 0.054 and 0.120 inch, and chromium-nickel steel sheet in thicknesses form 0.020 to 0.0275 inch. Significant differences were found between the tensile and the compressive stress-strain curves, and also the corr… more
Date: February 1942
Creator: Atchison, C. S. & Miller, James A.
Item Type: Refine your search to only Report
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Tidewater and Weather-Exposure Tests on Metals Used in Aircraft - 2

Description: "This report is an addendum to NACA Technical Note No. 736, which dealt with tidewater and weather-exposure tests being conducted by the National Bureau of Standards on various aluminum alloys, magnesium alloys, and stainless steels used in aircraft. The exposures were begun in June 1938 and were terminated, for this particular series, in June 1941. The methods of exposure and the materials being investigated are described, and the more important results obtained up to the conclusion of the sec… more
Date: February 1942
Creator: Mutchler, Willard & Galvin, W. G.
Item Type: Refine your search to only Report
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Correlation of knocking characteristics of fuels in an engine having a hemispherical combustion chamber

Description: From Summary: "Data are presented to show the effects of inlet-air pressure, inlet-air temperature, and compression ratio on the maximum permissible performance obtained with having a hemispherical-dome combustion chamber. The five aircraft-engine fuels used have octane numbers varying from 90 to 100 plus 2 ml of tetraethyl lead per gallon. The data were obtained on a 5 1/4-inch by 4 3/4-inch liquid-cooled engine operating at 2,500 r.p.m. The compression ratio was varied from 6.0 to 8.9. The in… more
Date: July 1940
Creator: Rothrock, A. M. & Biermann, Arnold E.
Item Type: Refine your search to only Report
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Shear Lag in Corrugated Sheets Used for the Chord Member of a Box Beam

Description: "The problem of the distribution of normal stress across a wide corrugated sheet used as the chord of a box-beam-like structure is investigated theoretically and experimentally. Expressions are developed giving the stress distribution in beams, symmetrical or unsymmetrical, about a plane passed spanwise through the center of the sheet. The experiments were arranged to insure bending without torsion and surveys of the normal stresses were made by means of mechanical and electrical strain gages" … more
Date: January 1941
Creator: Newell, Joseph S. & Reissner, Eric
Item Type: Refine your search to only Report
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Bearing strengths of some wrought-aluminum alloys

Description: From Introduction: "Although a number of investigations of the bearing strength of aluminum alloys have been made, the problem remains one of considerable interest to the aircraft industry. For this reason it has seemed advisable to make additional tests of the commonly used aircraft alloys in an effort to establish a better basis for the selection of allowable bearing values. Current design practice does not recognize the effect of edge distance upon bearing strengths, and for this reason edge… more
Date: August 1943
Creator: Moore, R. L. & Wescoat, C.
Item Type: Refine your search to only Report
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An investigation of the effectiveness of stiffeners on shear-resistant plate-girder webs

Description: From Summary: "The results of 60 different tests on 2 aluminum alloy 17S-T plate girders are presented to show the influence of size and spacing of stiffeners upon the buckling characteristics of shear-resistant webs within the elastic range. It is demonstrated that stiffeners increase the stability of a web by retarding the formation subdivided panels. An empirical method of proportioning stiffeners is proposed which recognizes both of these stiffener functions, and comparisons are made with d… more
Date: September 1942
Creator: Moore, R. L.
Item Type: Refine your search to only Report
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Description of Stress-Strain Curves by Three Parameters

Description: "A simple formula is suggested for describing the stress-strain curve in terms of three parameters; namely, Young's modulus and two secant yield strengths. Dimensionless charts are derived from this formula for determining the stress-strain curve, the tangent modulus, and the reduced modulus of a material for which these three parameters are given. Comparison with the tensile and compressive data on aluminum-alloy, stainless-steel, and carbon-steel sheet in NACA Technical Note No. 840 indicates… more
Date: July 1943
Creator: Ramberg, Walter & Osgood, William R.
Item Type: Refine your search to only Report
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Effects of Prior Fatigue-Stressing of the Impact Resistance of Chromium-Molybdenum Aircraft Steel

Description: Note presenting a study of the impact behavior of normalized SAE X4130 steel after a variety of repeated stress treatments. Fatigue specimens of several types were used and the effects of surface finish, rest periods, stress amplitude, mean stress, stress concentration, and temperature during repeated stress received consideration.
Date: March 1943
Creator: Kies, J. A. & Holshouser, W. L.
Item Type: Refine your search to only Report
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Spin Tests of a Low-Lying Monoplane in Flight and in the Free-Spinning Wind Tunnel

Description: "Comparative full-scale and model spin tests were made with a low-lying monoplane in order to extend the available information as to the utility of the free-spinning wind tunnel as an aid in predicting full-scale spin characteristics. For a given control disposition the model indicated steeper spins than were actually obtained with the airplane, the difference being most pronounced for spins with elevators up. Recovery characteristics for the model, on the whole, agreed with those for the airpl… more
Date: July 1940
Creator: Seidman, Oscar & McAvoy, William H.
Item Type: Refine your search to only Report
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A method for determining the column curve from tests of columns with equal restraints against rotation on the ends

Description: The results are presented of a theoretical study for the determination of the column curve from tests of column specimens having ends equally restrained against rotation. The theory of this problem is studied and a curve is shown relating the fixity coefficient c to the critical load, the length of the column, and the magnitude of the elastic restraint. A method of using this curve for the determination of the column curve for columns with pin ends from tests of columns with elastically restrai… more
Date: August 1943
Creator: Lundquist, Eugene E.; Rossman, Carl A. & Houbolt, John C.
Item Type: Refine your search to only Report
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The effects of various parameters on the load at which spray enters the propellers of a flying boat

Description: Report presenting the results of experiments with a technique for investigating the spray characteristics of flying-boat models. The forebody of a pointed-step flying boat hull was used for testing, and the effects of varying trim, propeller position, and amount of power were investigated. Either of the two types of spray that emanate from a forebody can limit the gross load of a flying boat depending on the configuration.
Date: May 1946
Creator: Dawson, John R. & Walter, Robert C.
Item Type: Refine your search to only Report
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Jet-boundary and plan-form corrections for partial-span models with reflection plane, end plate, or no end plate in a closed circular wind tunnel

Description: Report presenting a method for determining the jet-boundary and plan-form corrections necessary for application to test data for a partial-span model with a reflection plane, an end plate, or no end plate in a closed circular wind tunnel. Good agreement with three different conditions was obtained with flaps neutral at values of lift coefficient below the stall and somewhat less satisfactory agreement in the region of maximum lift coefficient or with flaps deflected.
Date: June 1946
Creator: Sivells, James C. & Deters, Owen J.
Item Type: Refine your search to only Report
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Stresses and Deflections in Thin Shells and Curved Plates Due to Concentrated and Variously Distributed Loading

Description: Note presenting tests made on cylindrical and spherical shells to determine the local stresses and deflections produced by concentrated and variously distributed loading. The results are correlated with those of earlier experiments, and empirical formulas based on the data are proposed. Data are presented on the effect of severe prestressing on stiffness and on the efficiency of welded lugs of various forms in transmitting a load to a thin shell without producing excessive local stresses.
Date: May 1941
Creator: Roark, Raymond J.
Item Type: Refine your search to only Report
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An Analysis of the Factors Affecting the State of Fuel and Air Mixtures

Description: From Introduction: "It is the purpose of this paper to describe the physical properties that are necessary to specify mixture quality in a system containing fuel and dry air and to evaluate the theoretical rolation between these properties and the physical properties of the mixture."
Date: May 1946
Creator: Gilbert, Mitchell; Howard, John N. & Hicks, Bruce L.
Item Type: Refine your search to only Report
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Pressure distribution over a plug-type spoiler-slot aileron on a tapered wing with full span slotted flaps

Description: From Summary: "A pressure-distribution investigation was made in the Langley 7- by 10-foot tunnel of a plug-type spoiler-slot aileron on a semispan tapered-wing model of a typical fighter airplane equipped with full-span slotted flaps. The results of the investigation indicate peak pressure on a plug-type spoiler-slot aileron that may result in a compressibility shock on the plug aileron at high speed. The maximum loads on the plug aileron occurred in the high-speed condition for maximum up ail… more
Date: June 1946
Creator: Lowry, John G. & Turner, Thomas R.
Item Type: Refine your search to only Report
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Summary and Analysis of Data on Damping in Yaw and Pitch for a Numbers of Airplane Models

Description: Note presenting damping data obtained from free-flight-tunnel tests of 13 models; the results are analyzed and compared with calculated results. The contributions of the wing, flaps, fuselage, tail surfaces, and power to the damping in pitch and yaw were studied. For complete models, fairly good agreement was obtained between experimental and calculated values for power-off, flaps-neutral conditions.
Date: May 1946
Creator: Cotter, William E., Jr.
Item Type: Refine your search to only Report
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The End-Plate Effect of a Horizontal-Tail Surface on Vertical Tail Surface

Description: Note presenting the end-plate effect of the horizontal-tail surface on the vertical-tail surface as theoretically studied by derivation of the flow corresponding to the condition of minimum induced drag and by solution of the usual lifting-line equations. The results obtained by the two methods were considerably different, indicated that the condition derived is not a close approximation to the actual condition.
Date: February 1941
Creator: Katzoff, S. & Mutterperl, William
Item Type: Refine your search to only Report
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Stress Analysis of Monocoque Fuselage Bulkheads by the Photoelastic Method

Description: Note presenting an investigation to determine the possibility of using the photoelastic method for the stress analysis of bulkheads in monocoque structures. The method was applied to several typical bulkheads including a circular ring with floor beam, a circular ring attached to the main wing spar, and a flying-boat bulkhead.
Date: December 1942
Creator: Ruffner, Benjamin F.
Item Type: Refine your search to only Report
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The Stability of Isotropic or Orthotopic Cylinders or Flat or Curved Panels, Between and Across Stiffeners, With Any Edge Conditions Between Hinged and Fixed, Under Any Combination of Compression and Shear

Description: Note presenting a theory that is meant to include all factors that are commonly present when determining the stability of isotropic or orthotropic cylinders or flat or curved panels under a variety of characteristics. The theory is based on the energy method and involves a number of approximations, some rather rough. It is a theory of elastic stability and, like other theories, assumes a construction with no imperfections of shape or elasticity.
Date: December 1943
Creator: Donnell, L. H.
Item Type: Refine your search to only Report
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The effect of the type of specimen on the shear strengths of driven rivets

Description: Report presenting tests of various types of riveted joint composed of 24S-T sheet and 1/8-inch A17S-T rivets in order to determine the effects of specimen type on shear strengths. The results indicated that there was only a slight variation in shear strength with considerable variation in the types of specimen.
Date: November 1943
Creator: Sharp, W. H.
Item Type: Refine your search to only Report
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Compression tests of some 17S-T aluminum-alloy specimens of I cross section

Description: Report presenting testing of specimens cut from a specially extruded I-beam of 17S-T aluminum alloy with one flange wider than the other under axial compression. Only the two longest specimens failed as columns, while the shorter ones failed by local buckling. The agreement between experimental and calculated values of critical stress can be improved by considering the effect of restraint at the loaded edges of the web and adopting a more accurate buckling treatment beyond the elastic range.
Date: March 1941
Creator: Hill, H. N.
Item Type: Refine your search to only Report
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