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A method for the calculation of external lift, moment, and pressure drag of slender open-nose bodies of revolution at supersonic speeds

Description: An approximate method is presented for the calculation of the external lift, moment, and pressure drag of slender open-nose bodies of revolution of supersonic speeds. The lift, moment, and pressure drag of a typical ram-jet body shape are calculated at Mach numbers 1.45, 1.60, 1.75, and 3.00; and the lift and moment results are compared with available experimental data. The agreement of the calculated lift and moment data with the experimental data is excellent. The pressure-drag comparison was… more
Date: December 29, 1945
Creator: Brown, Clinton E. & Parker, Hermon M.
Partner: UNT Libraries Government Documents Department
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Bending-Torsion Flutter Calculations Modified by Subsonic Compressibility Corrections

Description: From Summary: "A number of calculations of bending-torsion wing flutter are made at two Mach numbers, m=0 (incompressible case) and m=0.7, and results are compared. The air forces employed for the case of m=0.7 are based on Frazer's recalculation of Possio's results, which are derived on the assumption of small disturbances to the main flow. For ordinary wings of normal density and of low bending frequency in comparison with torsion frequency, the compressibility correction to the flutter speed… more
Date: December 18, 1945
Creator: Garrick, I. E.
Partner: UNT Libraries Government Documents Department
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Relation between spark-ignition engine knock, detonation waves, and autoignition as shown by high-speed photography

Description: "A critical review of literature bearing on the autoignition and detonation-wave theories of spark-ignition engine knock and on the nature of gas vibrations associated with combustion and knock results in the conclusion that neither the autoignition theory nor the detonation-wave theory is an adequate explanation of spark-ignition engine knock. A knock theory is proposed, combining the autoignition and detonation-wave theories, which introduces the idea that the detonation wave develops in auto… more
Date: December 5, 1945
Creator: Miller, Cearcy D.
Partner: UNT Libraries Government Documents Department
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Method of Matching Performance of Compressor Systems with that of Aircraft Power Sections

Description: "A method is developed of easily determining the performance of a compressor system relative to that of the power section for a given altitude. Because compressors, reciprocating engines, and turbines are essentially flow devices, the performance of each of these power-plant components is presented in terms of similar dimensionless ratios. The pressure and temperature changes resulting from restrictions of the charge-air flow and from heat transfer in the ducts connecting the components of the … more
Date: November 15, 1945
Creator: Bullock, Robert O.; Keetch, Robert C. & Moses, Jason J.
Partner: UNT Libraries Government Documents Department
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Effect of NACA Injection Impeller on Mixture Distribution of Double-Row Radial Aircraft Engine

Description: "The NACA injection impeller was developed to improve the mixture distribution of aircraft engines by discharging the fuel from a centrifugal supercharger impeller and thus to promote a thorough mixing of fuel and charge air. Experiments with a double-row radial aircraft engine indicated that for the normal range of engine power the NACA injection impeller provided marked improvement in mixture distribution over the standard spray-bar injection system used in the same engine. The mixture distri… more
Date: November 14, 1945
Creator: Marble, Frank E.; Ritter, William K. & Miller, Mahlon A.
Partner: UNT Libraries Government Documents Department
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The NACA high-speed motion-picture camera optical compensation at 40,000 photographs per second

Description: The principle of operation of the NACA high-speed camera is completely explained. This camera, operating at the rate of 40,000 photographs per second, took the photographs presented in numerous NACA reports concerning combustion, preignition, and knock in the spark-ignition engine. Many design details are presented and discussed, details of an entirely conventional nature are omitted. The inherent aberrations of the camera are discussed and partly evaluated. The focal-plane-shutter effect of th… more
Date: November 6, 1945
Creator: Miller, Cearcy D.
Partner: UNT Libraries Government Documents Department
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Summary report on the high-speed characteristics of six model wings having NACA 65(sub1)-series sections

Description: A summary of the results of wind-tunnel tests to determine the high-speed aerodynamic characteristics of six model wings having NACA 65sub1-series sections is presented in this report. The 8-percent-thick wings were superior to the 10-percent and 12-percent-thick wings from the standpoint of power economy during level flight for Mach numbers above 0.76. However, airplanes that are to fly at Mach numbers below 0.76 will gain aerodynamically if the percentage thickness of the wing and the aspect … more
Date: October 19, 1945
Creator: Hamilton, William T. & Nelson, Warren H.
Partner: UNT Libraries Government Documents Department
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Comparison of several methods of predicting the pressure loss at altitude across a baffled aircraft-engine cylinder

Description: Several methods of predicting the compressible-flow pressure loss across a baffled aircraft-engine cylinder were analytically related and were experimentally investigated on a typical air-cooled aircraft-engine cylinder. Tests with and without heat transfer covered a wide range of cooling-air flows and simulated altitudes from sea level to 40,000 feet. Both the analysis and the test results showed that the method based on the density determined by the static pressure and the stagnation temperat… more
Date: October 9, 1945
Creator: Neustein, Joseph & Schafer, Louis J., Jr.
Partner: UNT Libraries Government Documents Department
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Correlation of Exhaust-Valve Temperatures With Engine Operating Conditions and Valve Design in an Air-Cooled Cylinder

Description: "A semiempirical equation correlating exhaust-valve temperatures with engine operating conditions and exhaust-valve design has been developed. The correlation is based on the theory correlating engine and cooling variables developed in a previous NACA report. In addition to the parameters ordinarily used in the correlating equation, a term is included in the equation that is a measure of the resistance of the complex heat-flow paths between the crown of the exhaust valve and a point on the outs… more
Date: October 1945
Creator: Zipkin, M. A. & Sanders, J. C.
Partner: UNT Libraries Government Documents Department
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A method of analysis of V-G records from transport operations

Description: A method has been developed for interpreting v-g records taken during the course of commercial transport operation. This method involves the utilization of fairly simple statistical procedures to obtain "flight envelopes," which predict that, on the average, in a stated number of flight hours, one value of airspeed will exceed the envelope, and one positive and one negative acceleration increment will exceed the envelope with equal probability of being experienced at any airspeed. Comparison wi… more
Date: August 31, 1945
Creator: Peiser, A. M. & Wilkerson, M.
Partner: UNT Libraries Government Documents Department
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A Method of Analysis of V-G Records from Transport Operations

Description: A method has been developed for interpreting V-G records taken during the course of commercial transport operation. This method involves the utilization of fairly simple statistical procedures to obtain "flight envelopes," which predict that, on the average, in a stated number of flight hours, one value of airspeed will exceed the envelope, and one positive and one negative acceleration increment will exceed the envelope with equal probability of being experienced at any airspeed. Comparison wi… more
Date: August 31, 1945
Creator: Peiser, A. M. & Wilkerson, M.
Partner: UNT Libraries Government Documents Department
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Analysis and modification of theory for impact of seaplanes on water

Description: From Summary: "An analysis of available theory on seaplane impact and a proposed modification thereto are presented. In previous methods the overall momentum of the float and virtual mass has been assumed to remain constant during the impact but the present analysis shows that this assumption is rigorously correct only when the resultant velocity of the float is normal to the keel."
Date: August 20, 1945
Creator: Mayo, Wilbur L.
Partner: UNT Libraries Government Documents Department
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Comparison of wind-tunnel and flight measurements of stability and control characteristics of a Douglas A-26 airplane

Description: From Summary: "Stability and control characteristics determined from tests in the Langley 19-foot pressure tunnel of a 0.2375-scale model of the Douglas XA-26 airplane are compared with those measured in flight tests of a Douglas A-26 airplane. Agreement regarding static longitudinal stability as indicated by the elevator-fixed neutral points and by the variation of elevator deflection in both straight and turning flight was found to be good except at speeds approaching the stall. At these low … more
Date: August 11, 1945
Creator: Kayten, Gerald G. & Koven, William
Partner: UNT Libraries Government Documents Department
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Comparative drag measurements at transonic speeds of rectangular sweptback NACA 65-009 airfoils mounted on a freely falling body

Description: From Summary: "Directly comparable drag measurements have been made of an airfoil with a conventional rectangular plan form and an airfoil with a sweptback plan form mounted on freely falling bodies. Both airfoils had NACA 65-009 sections and were identical in span, frontal area, and chord perpendicular to the leading edge. The sweptback plan form incorporated a sweepback angle of 45 degrees. The data obtained have been used to establish the relation between the airfoil drag coefficients and th… more
Date: August 9, 1945
Creator: Mathews, Charles W. & Thompson, Jim Rogers
Partner: UNT Libraries Government Documents Department
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Some Effects of Compressibility on the Flow Through Fans and Turbines

Description: "The laws of conservation of mass, momentum, and energy are applied to the compressible flow through a two-dimensional cascade of airfoils. A fundamental relation between the ultimate upstream and downstream flow angles, the inlet Mach number, and the pressure ratio across the cascade is derived. Comparison with the corresponding relation for incompressible flow shows large differences. The fundamental relation reveals two ranges of flow angles and inlet Mach numbers, for which no ideal pressur… more
Date: August 1, 1945
Creator: Perl, W. & Epstein, H. T.
Partner: UNT Libraries Government Documents Department
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A visual photographic study of cylinder lubrication

Description: From Summary: "A V-type engine provided with a glass cylinder was used to study visually the lubrication characteristics of an aircraft-type piston. Photographs and data were obtained with the engine motored at engine speeds up to 1000 r.p.m. and constant cylinder-head pressures of 0 and 50 pounds per square inch. A study was made of the orientation of the piston under various operating conditions, which indicated that the piston was inclined with the crown nearest the major-thrust cylinder fac… more
Date: August 1, 1945
Creator: Shaw, Milton C. & Nussdorfer, Theodore
Partner: UNT Libraries Government Documents Department
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Charts for the Minimum-Weight Design of 24S-T Aluminum-Alloy Flat Compression Panels With Longitudinal Z-Section Stiffeners

Description: "Design charts are developed for 24S-T aluminum-alloy flat compression panels with longitudinal z-section stiffeners. These charts make possible the design of the lightest panels of this type for a wide range of design requirements. Examples of the use of the charts are given and it is pointed out on the basis of these examples that, over a wide range of design conditions, the maintenance of buckle-free surfaces does not conflict with the achievement of high structural efficiency" (p. 553).
Date: July 9, 1945
Creator: Schuette, Evan H.
Partner: UNT Libraries Government Documents Department
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The development and application of high-critical-speed nose inlets

Description: From Summary: "An analysis of the nose-inlet shapes developed in previous investigations to represent the optimum from the standpoint of critical speed has shown that marked similarity exists between the nondimensional profiles of inlets which have widely different proportions and critical speeds. With the nondimensional similarity of such profiles established, the large differences in the critical speeds of these nose inlets must be a function of their proportions. An investigation was underta… more
Date: June 8, 1945
Creator: Baals, Donald D.; Smith, Norman F. & Wright, John B.
Partner: UNT Libraries Government Documents Department
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An analysis of life expectancy of airplane wings in normal cruising flight

Description: From Summary: "In order to provide a basis for judging the relative importance of wing failure by fatigue and by single intense gusts, an analysis of wing life for normal cruising flight was made based on data on the frequency of atmospheric gusts. The independent variables considered in the analysis included stress-concentration factor, stress-load relation, wing loading, design and cruising speeds, design gust velocity, and airplane size. Several methods for estimating fatigue life from gust … more
Date: May 28, 1945
Creator: Putnam, Abbott A.
Partner: UNT Libraries Government Documents Department
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Investigation of the NACA 4-(5)(08)-03 and NACA 4-(10)(08)-03 two-blade propellers at forward Mach numbers to 0.725 to determine the effects of camber and compressibility on performance

Description: As part of a general investigation of propellers at high forward speeds, tests of two-blade propellers having the NACA 4-(5)(08)-03 and NACA 4-(10)(08)-03 blade designs were made in the Langley 8-foot high-speed tunnel through a range of blade angle from 20 degrees to 60 degrees for forward Mach numbers from 0.165 to 0.70 to determine the effect of camber and compressibility on propeller characteristics. Results previously reported for similar tests of a two-blade propeller having the NACA 4-(3… more
Date: May 7, 1945
Creator: Delano, James B.
Partner: UNT Libraries Government Documents Department
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A general representation for axial-flow fans and turbines

Description: A general representation of fan and turbine arrangements on a single classification chart is presented that is made possible by a particular definition of the stage of an axial-flow fan or turbine. Several unconventional fan and turbine arrangements are indicated and the applications of these arrangements are discussed.
Date: May 4, 1945
Creator: Perl, W. & Tucker, M.
Partner: UNT Libraries Government Documents Department
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Summary of Airfoil Data

Description: From Summary: "Recent airfoil data for both flight and wind-tunnel tests have been collected and correlated insofar as possible. The flight data consist largely of drag measurements made by the wake-survey method. Most of the data on airfoil section characteristics were obtained in the Langley two-dimensional low-turbulence pressure tunnel. Detail data necessary for the application of NACA 6-serles airfoils to wing design are presented in supplementary figures, together with recent data for the… more
Date: March 1945
Creator: Stivers, Louis S.; Abbott, Ira H. & von Doenhoff, Albert E.
Partner: UNT Libraries Government Documents Department
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Estimation of F-3 and F-4 knock-limited performance ratings for ternary and quaternary blends containing triptane or other high-antiknock aviation-fuel blending agents

Description: Charts are presented that permit the estimation of F-3 and F-4 knock-limited performance ratings for certain ternary and quaternary fuel blends. Ratings for various ternary and quaternary blends estimated from these charts compare favorably with experimental F-3 and F-4 ratings. Because of the unusual behavior of some of the aromatic blends in the F-3 engine, the charts for aromatic-paraffinic blends are probably less accurate than the charts for purely paraffinic blends.
Date: January 20, 1945
Creator: Barnett, Henry C.
Partner: UNT Libraries Government Documents Department
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