Technical Report Archive & Image Library (TRAIL) - 359 Matching Results
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- Adjustment of Stick Force by a Nonlinear Aileron-Stick Linkage
- Report presenting an application of the principle of aileron-stick forces and mechanical advantage to an aileron installation in which the stick forces are small over the low-deflection range and excessively large at full deflection.
- Aerodynamic Characteristics and Flap Loads of the Brake-Flap Installation on the 0.40-Scale Model of the F4F-3 Left Wing Panel
- "The data are presented in coefficient form and include lift, drag, and pitching-moment coefficients of the airfoil-flap comoinations and the normal-force, chord-force, and hinge-moment coefficients of the upper (perforated split) flap and lower (slotted) flap" (p. 1).
- Aerodynamic Characteristics for Internal-Balance and Frise Type Ailerons on an NACA 6 Series Low-Drag Tip Section of the Wing for the XP-63 Airplane
- Report presenting testing in the two-dimensional turbulence tunnel of a model of the tip section of the wing of the XP-63 airplane. Several alterations of the skirts and balance on the internal-balance aileron were tested to obtain various aerodynamic characteristics of the aileron.
- Aerodynamic Heat-Power Engine Operating on a Closed Cycle
- "Hot-air engines with dynamic compressors and turbines offer new prospects of success through utilization of units of high efficiencies and through the employment of modern materials of great strength at high temperature. Particular consideration is given to an aerodynamic prime mover operating on a closed circuit and heated externally. Increase of the pressure level of the circulating air permits a great increase of limit load of the unit. This also affords a possibility of regulation for which the internal efficiency of the unit changes but slightly. The effect of pressure and temperature losses is investigated" (p. 1).
- Aerodynamic problems in the design of efficient propellers
- From General Analysis: "The purpose of part I of this paper is to show how the loading that gives the minimum induced energy loss can be obtained from rather elementary considerations and to present design charts from which such a plan form can be quickly obtained for any set of design conditions."
- Aerodynamic Tests of an M-31 Bomb in the 8-Foot High-Speed Tunnel
- Report presenting aerodynamic tests of a 300-pound M-31 demolition bomb. Force tests at a range of angles of attack were made at Mach number 0.725, which corresponds to a speed of 810 feet per second at sea level. Results regard the drag, lift, and pitching moment are provided.
- The Aerodynamic Tests of Three Edo Floats for the SB2U-3, 0S2U-2, and XSB2C-2 Seaplanes - NACA Models 106-K, 107-K, and 125-AH
- Report presenting aerodynamic testing of scale models of the Edo seaplane floats for the SB2U-3, OS2U-2, and XSB2C-2 seaplanes. Various coefficients, pitching moment, yawing moment, and drag coefficients are provided.
- Aerodynamics of the Fuselage
- "The present report deals with a number of problems, particularly with the interaction of the fuselage with the wing and tail, on the basis of simple calculating method's derived from greatly idealized concepts. For the fuselage alone it affords, in variance with potential theory, a certain frictional lift in yawed flow, which, similar to the lift of a wing of small aspect ratio, is no longer linearly related to the angle of attack. Nevertheless there exists for this frictional lift something like a neutral stability point the position of which on oblong fuselages appears to be associated with the lift increase of the fuselage in proximity to the zero lift, according to the present experiments" (p. 1).
- Analyses of West Virginia Coals
- Technical paper issued by the Bureau of Mines over studies of West Virginia coal fields. Characteristics of coals and mines are discussed. This paper includes tables, maps, and illustrations.
- Analysis of Heat and Compressibility Effects in Internal Flow Systems and High-Speed Tests of a Ram-Jet System
- Report presenting an analysis of the effects of heat and compressibility in the flow through the internal systems of aircraft. Equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
- Analysis of Heat and Compressibility Effects in Internal Flow Systems and High-Speed Tests of a Ram-Jet System
- Report discussing an analysis has been made by the NACA of the effects of heat and compressibility in the flow through the internal systems of aircraft along with equations and charts are developed whereby the flow characteristics at key stations in a typical internal system may be readily obtained.
- An analysis of the effect of core structure and performance on volume and shape of cross-flow tubular intercoolers
- From Introduction: "The purpose of this paper is to show, in a similar manner, the effect of change in the core structure of the tubular intercooler on the over-all dimensions when the operating conditions are fixed."
- Analytical Theory of the Campini Propulsion System
- "The present report deals exclusively with the particular jet-propulsion system mentioned in the cited reports. The discussion is limited, for the present, to the analytical study of the efficiency and the consumption for the case of application to aircraft and to the plotting of the practical operating curves secured theoretically by the use of suitable experimental factors" (p. 1).
- Annual Report of the Explosives Division, Fiscal Year 1942
- Report issued by the U.S. Bureau of Mines on the annual report of work conducted by the Explosives Division during the fiscal year of 1942. Descriptions of testing projects and operations are presented. This report includes tables, graphs, illustrations, and photographs.
- Annual Report of the Mining Division, Fiscal Year 1942
- Report issued by the U.S. Bureau of Mines on the annual work conducted by the Mining Division during 1942. Descriptions of projects and operations during the fiscal year are listed. This report contains tables, and photographs.
- Annual Report of the National Advisory Committee for Aeronautics (27th). Administrative Report Including Technical Report Nos. 704 to 726
- Report includes the National Advisory Committee for Aeronautics letter of submittal to the President, summaries of the committee's activities and research accomplished, bibliographies, and financial report.
- Antimony Deposits of the Stampede Creek Area, Kantishna District, Alaska
- From abstract: The Stampede Creek area lies about 120 miles southwest of Fairbanks, Alaska. It is most readily accessible by air during the summer and by tractor road during the winter. Since 1936 approximately 2,400 tons of shipping-grade antimony ore and concentrates, containing about 1,300 tons of metallic antimony, have been produced at the Stampede mine. The mine was closed down in the spring of 1941, principally because of the high cost of transportation. The area is underlain largely by metamorphosed rocks of the Birch Creek schist. The schist has been warped and crumpled into many broad, open folds which strike northeast and also plunge to the northeast. The Stampede mine is in the schistose quartzite member of the Birch Creek schist.
- Application of Balancing Tabs to Ailerons
- Analysis was made to determine characteristics required of a balancing-tab system for ailerons in order to reduce aileron stick forces to any desired magnitude. Series of calculations based on section data were made to determine balancing-tab systems of various chord tabs and ailerons that will give, for a particular airplane, zero rate of aileron hinge moment with aileron deflection and yet will produce same maximum rate of roll as a plain unbalanced 15-percent chord aileron of same span. Effects of rolling velocity and of forces in tab link on aileron hinge moments have been included.
- An Attempted Separation of Mercury Isotopes
- The following document describes the analysis on an attempt at separating mercury isotopes by making their environments as widely different as possible.
- Beam and torsion tests of aluminum-alloy 615-T tubing
- From Summary: "Tests were made to determine the effect of length and the effect of ratios of diameter to wall thickness upon the flexural and torsional moduli of failure of 61S-T aluminum-alloy tubing. The moduli of failure in bending, as determined by tests in which the tubing was loaded on the neutral axis at the one-third points of the span, were found to bear an approximately linear relationship with diameter-thickness ratio and were practically independent of span within the limits investigated. Empirical equations are given describing the relations obtained. The moduli of failure in torsion were found to be dependent upon length as well as upon diameter-thickness ratios. Empirical equations are given for predicting strengths within the range of plastic buckling. Within the elastic range, available torsion theories were found to be satisfactory."
- Bending of Rectangular Plates with Large Deflections
- "The solution of von Karman's fundamental equations for large deflections of plates is presented for the case of a simply supported rectangular plate under combined edge compression and lateral loading. Numerical solutions are given for square plates and for rectangular plates with a width-span ratio of 3:1. The effective widths under edge compression are compared with effective widths according to von Karman, Bengston, Marguerre, and Cox and with experimental results by Ramberg, McPherson, and Levy" (p. 1).
- Bending tests of a monocoque box
- A monocoque box beam consisting of a 24S-T aluminum-alloy sheet reinforced by four bulkheads and by longitudinal stringers and corner posts was subjected to bending loads as follows: pure bending about the lift axis, cantilever bending about the lift axis, and pure bending about both lift and drag axis. Longitudinal strains were measured for loads up to a load at which permanent set became measurable. The loads were sufficient to produce buckling of the sheet between stringers on the compression side of the box. The only noticeable effect of this buckling was a small increase in extreme-fiber strain on the compression side. The measured strains and measured deflections differed less than 10 percent from those computed from the simple beam theory after taking account of the effective width of the buckled sheet. The effect of the bulkheads on the distribution of stringer strain was negligible.
- Bending With Large Deflection of a Clamped Rectangular Plate With Length-Width Ratio of 1.5 Under Normal Pressure
- "The Von Karman equations for a thin flat plate with large deflections are solved for the special case of a plate with clamped edges having a ratio of length to width of 1.5 and loaded by uniform normal pressure. Center deflections, membrane stresses, and extreme-fiber bending stresses are given as a function of pressure for center deflections up to twice the thickness of the plate. For small deflections the results coincide with those obtained by Hencky from the linear theory" (p. 1).
- A Brief Study of the Speed Reduction of Overtaking Airplanes by Means of Air Brakes
- "As an aid to airplane designers interested in providing pursuit airplanes with decelerating devices intended to increase the firing time when overtaking another airplane, formulas are given relating the pertinent distances and speeds in horizontal flight to the drag increase required. Charts are given for a representative parasite-drag coefficient from which the drag increase, the time gained, and the closing distance may be found. The charts are made up for three values of the ratio of the final speed of the pursuing airplane to the speed of the pursued airplane and for several values of the ratio of the speed of the pursued airplane to the initial speed of the pursuing airplane" (p. 1).
- Calculated effects of full-span slotted and Fowler flaps on longitudinal stability and control characteristics for a typical fighter-type airplane with various tail modifications
- Report presenting an analytical study of the influence of full-span slotted and Fowler flaps on the requirements for horizontal tail surfaces. The elevator deflection required to land at three-point attitude, elevator deflection required to stall the airplane at altitude, and permissible center-of-gravity range have been calculated for a fighter-type airplane.
- Calculation of tab characteristics for flight conditions from wind-tunnel data
- Report presenting tail-surface characteristics calculated from wind-tunnel data, which have been reported to not correspond with flight-test measurements. The primary problem under consideration is the calculation of the effect of tab deflection on the free-floating angle of the elevator, as in a servocontrol.
- Calibration of Three Temperature Probes and a Pressure Probe at High Speeds
- "Three Franz-type temperature probes and a pitot-static tube for use in supercharger passages have been calibrated in the NACA 24-inch high-speed wind tunnel. These instruments were designed for use in supercharger investigations" (p. 1).
- Calibrations of pitot-static tubes at high speeds
- Report presenting the calibrations of three types of service pitot-static tubes over an approximate range of speeds of 150 to 600 miles per hour. The calibrations indicated a need for a pitot-static tube with greater accuracy, especially at higher speeds. Results regarding the service tubes, Prandtl tube, Eigh-speed tube, and a comparison of the tubes are provided.
- Capture Cross Section of Si for Thermal Neutrons
- The following report analyzes different values and measurements that give the same results for the captured cross section of thermal neutrons for Si.
- Characteristics of beveled-trailing-edge elevators on a typical pursuit fuselage at altitudes simulating-normal flight and spin conditions
- 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.
- Characteristics of plain and balanced elevators on a typical pursuit fuselage at attitudes simulating normal-flight and spin conditions
- Report presenting lift and elevator hinge-moment characteristics of a horizontal tail with various plain and balanced elevators and mounted on a typical pursuit fuselage as measured in the 7- by 10-foot wind tunnel at attitudes simulating normal-flight and spin conditions. The lift effectiveness of the elevator was practically independent of the size of the aerodynamic balance. Results regarding the fuselage alone and fuselage interference, lift characteristics of fuselage-tail combinations, lift effectiveness of the tab, elevator hinge moments, parameters, effect of yaw on elevator hinge moments, effect of tab on elevator hinge moments, drag, and comparison with two-dimensional data are provided.
- The Characteristics of Two Model Six-Blade Counterrotating Pusher Propellers of Conventional and Improved Aerodynamic Design
- Two airfoil plans were used for propeller blades. One is modified Clark Y section designed for structural reliability and the second an NACA 16 airfoil section designed to produce minimum aerodynamic losses. At low air speeds, the propeller designed for aerodynamic effects showed a gain of from 1.5 to 4.0 percent in propulsive efficiency over the conventional type depending on the pitch. Because of the numerous variables involved, the effect of each one on the aerodynamic characteristics of the propellers could not be isolated.
- Chromite and quicksilver deposits of the Del Puerto area, Stanislaus County, California
- From Introduction: "The present report is based on 10 weeks of field work from mid-November 1940 until late January 1941, and 4 days in May 1941. An area of 5 1/2 square miles in and about Del Puerto Canyon was mapped on a scale of 600 feet to 1 inch, and two small areas in the vicinity of the Adobe Canyon and Black Bart chromite mines were mapped on a scale of 200 feet to 1 inch."
- Chromite deposits of Kenai Peninsula, Alaska
- This report describes field work and research done in two areas of ultramafic rocks containing chromite deposits are known at the south end of Kenai Peninsula, Alaska. The Red Mountain is the other area covered in this report.
- Chromite Deposits of Red Bluff Bay and Vicinity, Baranof Island, Alaska
- From introduction: The Red Bluff Bay area was examined briefly for the Geological Survey by John C. Reed and others in 1939. During the summer of 1941 the writers, with R. E. L. Rutledge, mapped this area on a scale of 1:12,000, and examined the serpentine masses in the interior during the course of reconnaissance trips into the surrounding region.
- Coal-Mine Accidents in the United States, 1939
- Report compiled by the U.S. Bureau of Mines including statistics on fatal and non-fatal accidents in coal mines located in the United States as well as data regarding the various operations (e.g., number of miners employed and average production). The information is organized into tables for comparison and the text draws some overall conclusions in the summary.
- Coal-Mine Accidents in the United States, 1940
- Report compiled by the U.S. Bureau of Mines including statistics on fatal and non-fatal accidents in coal mines located in the United States as well as data regarding the various operations (e.g., number of miners employed and average production). The information is organized into tables for comparison and the text draws some overall conclusions in the summary.
- Comparison of Intercooler Characteristics
- Report presenting a method of comparing the performance, weight, and general dimensional characteristics of intercoolers. The performance and dimensional characteristics covered in the comparisons include cooling effectiveness, pressure drops and weight flows of the charge and cooling air, power losses, volume, frontal area, and width.
- A comparison of the results from general tank tests of 1/6- and 1/12-full-size models of the British Singapore IIC flying boat
- From Summary: "A 1/6-full-size model of the hull of the British Singapore IIC flying boat was tested in the NACA tank. The results are given in the form of charts and are compared with the results of previous tests made in the NACA tank of a 1/12-full-size model, published in NACA T.N. No. 580, and with the results of tests made in the British R.A.E. tank of another 1/6-full-size model of the same hull. When the data from the tests of the 1/6- and 1/12-full-size models were compared on the basis of Froude's law of comparison, differences were found."
- Comparison of tightness of 78 degrees machine-countersunk rivets driven in holes prepared with 78 degrees and 82 degrees countersinking tools
- Report presenting an investigation to determine whether the use of a 78 degree countersinking tool instead of a 82 degree countersinking tool for riveting would substantially alter the conclusion reached in a previous paper regarding the placement of rivets for maximum strength.
- The Compressible Potential Flow Past Elliptic Symmetrical Cylinders at Zero Angle of Attack and with No Circulation
- "For the tunnel corrections of compressible flows those profiles are of interest for which at least the second approximation of the Janzen-Rayleigh method can be applied in closed form. One such case is presented by certain elliptical symmetrical cylinders located in the center of a tunnel with fixed walls and whose maximum velocity, incompressible, is twice the velocity of flow. In the numerical solution the maximum velocity at the profile and the tunnel wall as well as the entry of sonic velocity is computed" (p. 1).
- Condensation trails: Where they occur and what can be done about them
- Report presenting a brief, nontechnical discussion of condensation trails for flying personnel. World maps showing trail-forming zones at different altitudes and seasons are presented. Means for suppression trails are given.
- Construction of Finned Aluminum Muffs for Aircraft Engine Cylinder Barrels
- "This report describes the material, cutting-tool development, and machining procedure used in constructing an air-cooled cylinder barrel having a cooling muff with 2-inch fins spaced 1/8 inch. Details of two types of thread form used for the barrel to head assembly with the cooling muff are also presented" (p. 1).
- Contribution to the Design of Plywood Shells
- "The writer sets out to prove by calculation and experiment that by extensive utilization of the skin to carry axial load (reduction of stringer spacing) the stringer sections can be made small enough to afford a substantial saving in structural weight. This saving ranges from 5 to about 40 percent" (p. 1).
- Contribution to the ideal efficiency of screw propellers
- From Summary: "The stipulation of best thrust distribution is applied to the annular elements of the screw propeller with infinitely many blades in frictionless, incompressible flow and an ideal jet propulsion system derived possessing hyperbolic angular velocity distribution along the blade radius and combining the advantage of uniform thrust distribution over the section with minimum slipstream and rotation losses. This system is then compared with a propeller possessing the same angular velocity at all blade elements and the best possible thrust distribution secured by means of an induced efficiency varying uniformly over the radius. Lastly, the case of the lightly loaded propeller also is discussed."
- Control-Motion Studies of the PBM-3 Flying Boat in Abrupt Pull-Ups
- Report presenting a control-motion study in flight that is part of series covering a range of types and sizes of modern airplanes. This particular one involves the PBM-3 flying boat, which is equipped with a control mechanism typical of the cable-type systems in large transport, cargo, or bomber airplanes as well as those employed in flying boats. The elasticity of the elevator control system of the PBM-3 was such to limit the obtainable acceleration to about 3g for center-of-gravity positions in the usual operating range; that is, 26 to 30 percent mean aerodynamic chord, and for the range of airspeeds covered by the tests.
- Control of Torsional Vibrations by Pendulum Masses
- "Various versions of pendulum masses have been developed abroad within the past few years by means of which resonant vibrations of rotating shafts can be eliminated at a given tuning. They are already successfully employed on radial engines in the form of pendulous counterweights. Compared with the commonly known torsional vibration dampers, the pendulum masses have the advantage of being structurally very simple, requiring no internal damping and being capable of completely eliminating certain vibrations" (p. 1).
- Cooling in Cruising Flight With Low Fuel-Air Ratios
- Report presenting testing of a Pratt & Whitney R-1830-43 engine mounted in a B-24D nacelle in the full-scale wind tunnel in order to investigation the potential improvements of fuel economy. Suggestions for improving the cruising power and cruising range by operating at specified fuel-air ratios are provided.
- Cooling Investigation of a B-24D Engine-Nacelle Installation in the NACA Full-Scale Tunnel
- Report presenting an investigation conducted in the full-scale tunnel to determine methods of improving the cooling of the B-24D engine installation. The B-24D is a four-engine high-wing monoplane having a span of 110 feet, a wing area of 1048 square feet, and a gross weight of 56,000 pounds.
- Cooling Tests of an Air-Cooled Engine Cylinder With Copper Fins on the Barrel
- Report presenting the results of comparative cooling tests run on two Wright C9GC (G-200) cylinders, one with the original steel fins and one with 1-inch spiral copper fins brazed on the barrel. Calculations were also performed using copper and aluminum fins with the same weight as the original steel fins, which showed positive results. Results regarding cylinder-temperature correlation, piston-temperature correlation, and comparative performance are also provided.