Technical Report Archive & Image Library (TRAIL) - 331 Matching Results

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Causes of cracking of ignition cable

Description: From Summary: "The experiments described here show that the cracking at sharp bends, observed in the insulation of internal combustion engine high tension ignition wires after service, is due to a chemical attack upon the rubber by the ozone produced by the electric discharge that takes place at the surface of the cable. This cracking does not occur if the insulating material is not under tension, or if the cable is surrounded by some medium other than air. But it does occur even if the insulat… more
Date: February 1921
Creator: Dempsey, J. B. & Silsbee, F. B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Center of pressure coefficients for airfoils at high speeds

Description: "It has been customary to calculate the strength of the rear wing beam for the 'high speed' condition on the assumption that the center of pressure was at 0.50 of the wing chord. It can be shown that this assumption is not justified, regardless of the utility of a 'high speed' condition in strength calculations" (p. 1).
Date: April 1922
Creator: Diehl, W. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Characteristics of the N.A.C.A 97, Clark Y, and N.A.C.A. M6 Airfoils with Particular Reference to the Angle of Attack

Description: Report examining the aerodynamic characteristics of three airfoil sections as determined in the variable density wind tunnel. Particular attention is given to the relation of the characteristics to the angle of attack and their use in airplane design.
Date: December 1927
Creator: Higgins, George J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The characteristics of the N.A.C.A. M-12 airfoil section

Description: The data obtained on the NACA M-12 airfoil, tested at twenty atmosphere density in the NACA variable density wind tunnel, have been extended by additional tests at one and at twenty atmospheres under improved conditions. The results of these tests are given. Considerable scale effect was found.
Date: August 1926
Creator: Higgins, George J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Choice of the Speed of an Airship

Description: The favorable speed of an airship is chiefly determined by the condition of the consumption of the least amount of fuel per unit of traveled distance, although other conditions come into play. The resulting rules depend on the character of the wind and on the variability of the efficiency of the engine propeller units. This investigation resulted in the following rules. 1) Always keep the absolute course and steer at such an angle with reference to it as to neutralize the side wind. 2) In a str… more
Date: March 1922
Creator: Munk, Max M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The Choice of Wing Sections for Airplanes

Description: "The subject of the choice of an airfoil section is by no means a closed one, and despite the impossibility of making a single rule serve, it is quite practicable to deduce in a strictly rational manner a series of rules and formulas which are capable of being of the greatest use if we but confine ourselves to the consideration of one element of performance at a time. There are seven such elements of performance which are here taken up in turn. The seven are of different relative importance in … more
Date: November 1921
Creator: Warner, Edward P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparing Maximum Pressures in Internal Combustion Engines

Description: Thin metal diaphragms form a satisfactory means for comparing maximum pressures in internal combustion engines. The diaphragm is clamped between two metal washers in a spark plug shell and its thickness is chosen such that, when subjected to explosion pressure, the exposed portion will be sheared from the rim in a short time.
Date: June 1922
Creator: Sparrow, Stanwood W. & Lee, Stephen M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Comparing the Performance of Geometrically Similar Airplanes

Description: "This note has been prepared for the National Advisory Committee for Aeronautics. It deals with the model rules relating to aeronautical problems, and shows how the characteristics of one airplane can be determined from those of another airplane of different weight or size, and of similar type. If certain rules for the ratios of the dimensions, the weights and the horsepower are followed, a small low-powered airplane can be used for obtaining information as to performance, stability, controllab… more
Date: April 1924
Creator: Munk, Max M. & Warner, Edward P.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Comparison of Propeller and Centrifugal Fans for Circulating the Air in a Wind Tunnel

Description: The tests described in this paper afford a direct comparison of the efficiency and smoothness of flow obtained with propeller fan and multiblade centrifugal fan drives in the same wind tunnel. The propeller fan was found to be superior to the centrifugal fan in that the efficiency was about twice as great, and the flow much smoother.
Date: March 1928
Creator: Weick, Fred E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The comparison of well-known and new wing sections tested in the variable density wind tunnel

Description: Three groups of airfoils have been tested in the variable density wind tunnel. The first group contains three airfoils. The second group is a systematic series of twenty-seven airfoils. The third group consists of several frequently used wing sections.
Date: May 1925
Creator: Higgins, George J.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Compressive Strength of Tapered Airplane Struts

Description: Methods are here given for ascertaining the value of n in Euler's simplified formula, P = n (EI/l(sup 2)), for the compressive strength of tapered airplane struts, by estimating from curves and by calculation.
Date: December 1923
Creator: Lewe, Viktor
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Condensed Data on the Aircraft Engines of the World

Description: This compilation of the outstanding characteristics of the available aircraft engines of the world was prepared as a compact ready reference for desk use. It does not pretend to be anything but a skeleton outline of the characteristics of engines reported in the technical press as being in either the experimental, development, or production stage. At present progress is quite rapid and by the time this compilation is disseminated new models may have superseded those listed, or changes may have … more
Date: April 1929
Creator: Fliedner, C. S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Correcting Engine Tests for Humidity

Description: Note presenting tests using a multicylinder engine to determine the effect that atmospheric humidity has on some phases of engine performance. Three test series with different types of fuel were carried out. The results indicate that failure to allow for the effect of differences in atmospheric humidity may introduce errors as great as would be occasioned by failure to allow for changes in barometric pressure.
Date: June 1929
Creator: Brooks, Donald B.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Embrittlement of Duralumin I: Practical Aspects of the Problem

Description: Since aircraft design is tending toward all-metal construction, the strong heat-treatable light aluminum alloy, duralumin (a generic name for a class of heat-treatable alloys containing Cu, Mg, Mn, and Si), is finding increasing application. Doubt has been expressed concerning the reliability and permanence of these materials. Information is given on the effect of corrosion on the tensile properties of 14-gauge sheet duralumin, heat treated by quenching in hot water after being heated for 15 mi… more
Date: April 1928
Creator: Rawdon, Henry S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Embrittlement of Duralumin II: Accelerated Corrosion Tests and the Behavior of High-Strength Aluminum Alloys of Different Compositions

Description: The permanence, with respect to corrosion, of light aluminum alloy sheets of the duralumin type, that is, heat-treatable alloys containing Cu, Mg, Mn, and Si is discussed. Alloys of this type are subject to surface corrosion and corrosion of the interior by intercrystalline paths. Results are given of accelerated corrosion tests, tensile tests, the effect on corrosion of various alloying elements and heat treatments, electrical resistance measurements, and X-ray examinations.
Date: April 1928
Creator: Rawdon, Henry S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Embrittlement of Duralumin III: Effect of the Previous Treatment of Sheet Material on the Susceptibility to This Type of Corrosion

Description: As a result of testing, it was determined that control of the rate of quenching and the avoidance of accelerated aging by heating are the only means of modifying duralumin itself so as to minimize the intercrystalline form of corrosive attack. It is so simple a means that it should be adopted even though it may not completely prevent, but only reduce, this form of corrosive attack. By so doing, the need for protection of the surface is less urgent.
Date: April 1928
Creator: Rawdon, Henry S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Embrittlement of Duralumin IV: The Use of Protective Coatings

Description: Although the corrosion resistance of sheet duralumin can be greatly improved by suitable heat treatment, protection of the surface is still necessary if long life under varied service conditions is to be insured. The coatings used for this purpose may be grouped into three classes: the varnish type of coating, the oxide type produced by a chemical treatment of the surface, and metallic coatings, of which aluminum appears to be the most promising. Since the necessary weather exposure tests are n… more
Date: April 1928
Creator: Rawdon, Henry S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Embrittlement of Duralumin. V: Results of Weather-Exposure Tests

Description: In a series of weather exposure tests of sheet duralumin, upon which accelerated corrosion tests in the laboratory by the wet-and-dry corrosion method in a sodium chloride solution has already been carried out, a close parallelism between the results of the two kinds of tests was found to exist. The exposure tests showed that the lack of permanence of sheet duralumin is largely, if not entirely, due to corrosion. A corrosion attack of an intercrystalline nature is very largely responsible for t… more
Date: February 1929
Creator: Rawdon, Henry S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Corrosion Embrittlement of Duralumin. VI: The Effect of Corrosion Accompanied by Stress on the Tensile Properties of Sheet Duralumin

Description: The effect of corrosion on the tensile properties of duralumin while stressed is shown in graphical form. According to the test results, duralumin sheet, coated with aluminum, maintains its initial properties unimpaired for corrosion periods as long as 60 days with an applied tensile stress as high as 20,000 lb/sq.in., which is approximately one-half the stress corresponding to the yield point as defined here. In these tests, that material which had been heat-treated by being quenched in cold w… more
Date: May 1929
Creator: Rawdon, Henry S.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Crippling Strength of Axially Loaded Rods

Description: A new empirical formula was developed that holds good for any length and any material of a rod, and agrees well with the results of extensive strength tests. To facilitate calculations, three tables are included, giving the crippling load for solid and hollow sectioned wooden rods of different thickness and length, as well as for steel tubes manufactured according to the standards of Army Air Services Inspection. Further, a graphical method of calculation of the breaking load is derived in whic… more
Date: October 1921
Creator: Natalis, F. & Pawlowski, F. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Curves Showing Column Strength of Steel and Duralumin Tubing

Description: Given here are a set of column strength curves that are intended to simplify the method of determining the size of struts in an airplane structure when the load in the member is known. The curves will also simplify the checking of the strength of a strut if the size and length are known. With these curves, no computations are necessary, as in the case of the old-fashioned method of strut design. The process is so simple that draftsmen or others who are not entirely familiar with mechanics can c… more
Date: May 1929
Creator: Ross, Orrin E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Curvilinear Flight of Airplanes

Description: Note presenting an investigation of curvilinear flight, which is defined as steady horizontal flight in a circle in which no side slip occurs. The investigation occurred under very specific circumstances and rests on two basic assumptions, which are that the airplane lies correctly in the turn so the resultant of gravity and centrifugal force falls in the plane of symmetry and that the airplane must lie in the turn so that the axis coincides with the direction of motion.
Date: January 1924
Creator: Salkowski, E.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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A Dangerous Seaplane Landing Condition

Description: "A peculiar phenomena in seaplane landing is observed and reported. The seaplane having executed a normal fast landing at low incidence, a forward movement of the control stick effected an unusual condition in that the seaplane left the water suddenly in an abnormal attitude. The observations describing this phenomena are offered as a warning against possible accident and as a conjectural cause of seaplane landing accidents of a certain kind" (p. 1).
Date: May 1928
Creator: Carroll, Thomas
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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