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Aerodynamic Characteristics of a Number of Modified NACA Four-Digit-Series Airfoil Sections

Description: Theoretical pressure distributions and measured lift, drag, and pitching moment characteristics at three values of Reynolds number are presented for a group of NACA four-digit-series airfoil sections modified for high-speed applications. The effectiveness of flaps applied to these airfoils and the effect of standard leading-edge roughness were also investigated at one value of Reynolds number. Results are also presented of tests of three conventional NACA four-digit-series airfoil sections.
Date: November 14, 1947
Creator: Loftin, Laurence K., Jr. & Cohen, Kenneth S.
Item Type: Refine your search to only Report
open access

Analysis of cooling limitations and effect of engine-cooling improvements on level-flight cruising performance of four-engine heavy bomber

Description: From Introduction: "The difficulties experienced in cooling the exhaust-valve seats of the rear-row cylinders have been overcome to a considerable extent by improving the mixture distribution through application of the injection impeller (reference 1) and by augmenting the flow of cooling air to the critical baffles (reference 2). Flight tests of this airplane (reference 3) indicated that the temperatures of exhaust-valve seats on rear-row cylinders were markedly lowered by these modifications … more
Date: March 14, 1946
Creator: Marble, Frank E.; Miller, Marlon A. & Bell, E. Barton
Item Type: Refine your search to only Report
open access

The Bragg Reflection of Neutrons by a Single Crystal

Description: From cover page: This document has been assigned the above MDDC (Manhattan District Declassification) number, as given in the List of Declassified Documents issued semi-monthly by the Research Division, Manhattan District. In the case of Los Alapnos reports, LADC (Los Alamos Declassification) numbers are listed on the title page if known. This declassified document may differ materially from the original classified document by reason of deletions necessary to accomplish declassification. Hence,… more
Date: June 14, 1946
Creator: Zinn, Walter H.
Item Type: Refine your search to only Report
open access

Calculation of the Temperature Distribution in a Slug With a Solid Aluminum Cap

Description: Calculations were made to determine the temperature at various points of a thick disc and cap, on the assumptions that the heat production rate is uniform throughout the slug and that the slug is in perfect thermal contact with the cap. Results obtained by different methods of computation are compared with each other and with results obtained by Drew on the Paschkis electrical network computer at Columbia University.
Date: April 14, 1944
Creator: Murray, F. H.; Karush, William; Ginsburg, M. & Young, G.
Item Type: Refine your search to only Report
open access

Canopy loads investigation for the F6F-3 airplane

Description: Report presenting an investigation of surface static pressures over the outer and inner surfaces of the cockpit canopies on the Grumman F6F-3, Curtiss SB2C-4E, and Grumman F8F-1 airplanes in the full-scale tunnel. Results regarding the external pressure distribution and internal static pressure are provided.
Date: April 14, 1947
Creator: Cocke, Bennie W., Jr. & Czarnecki, K. R.
Item Type: Refine your search to only Report
open access

A comparison of theoretical and experimental loading on a 63 degrees swept-back wing at supersonic speeds

Description: Report presenting the pressure distribution over a highly swept wing at supersonic speeds to provide data for a comparison of measured and predicted loadings. The wing for this investigation had 63 degrees of sweepback of the leading edge, an aspect ratio of 3.5, and a taper ratio of 0.25. Over the regions influenced by the wing tip and trailing edge, the effects of viscosity apparently are responsible for the poorer agreement between theory and experiment.
Date: September 14, 1949
Creator: Stevens, Victor I. & Boyd, John W.
Item Type: Refine your search to only Report
open access

Critical Compressive Stress for Outstanding Flanges

Description: A chart is presented for the values of the coefficient in the formula for the critical compressive stress at which buckling may be expected to occur in outstanding flanges. These flanges are flat rectangular plates supported along the loaded edges, supported and elastically restrained along one unloaded edge, and free along the other unloaded edge. The mathematical derivations of the formulas required for construction of the chart are given.
Date: March 14, 1941
Creator: Lundquist, Eugene E. & Stowell, Elbridge Z.
Item Type: Refine your search to only Report
open access

The Distribution of the Positive-Negative Ratio for Mesons

Description: Positive and negative mesons produced in a common target in the cyclotron are received in two photographic plates. In the magnetic field of the cyclotron, negatives are deflected to one plate, positives to the other. The mesons must pass through an absorber before entering the plates in order to be observable.
Date: December 14, 1949
Creator: Rankin, Bayard, 1924-
Item Type: Refine your search to only Report
open access

Ditching Tests with a 1/16-Size Model of the Navy XP2V-1 Airplane at the Langley Tank No. 2 Monorail

Description: "Tests were made with a 1/16 size dynamically similar model of the Navy XP2V-1 airplane to study its performance when ditched. The model was ditched in calm water at the Langley tank no. 2 monorail. Various landing attitudes, speeds, and conditions of damage were simulated" (p. 1).
Date: March 14, 1947
Creator: Fisher, Lloyd J. & Tarshis, Robert P.
Item Type: Refine your search to only Report
open access

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.
Item Type: Refine your search to only Report
open access

Effect of Routing Upon Temperature of Cooling Stream

Description: With discussion under way concerning power production by chain reacting piles, it becomes pertinent to consider the ration of the temperature of the hottest spot in the pile to the average exit temperature of the cooling stream. This is important because the temperature of the hottest spot in the pile is one of the limiting factors in determining the maximum power at which a pile can be operated. However, the higher the temperature of the emerging cooling stream, the more efficient can be the t… more
Date: February 14, 1946
Creator: Cahn, Albert S., Jr.
Item Type: Refine your search to only Report
open access

The Effectiveness at High Speeds of a 10-Percent-Chord Plain Trailing-Edge Flap on the NACA 65-210 Airfoil Section

Description: This report contains the results of a high-speed wind-tunnel investigation of the effectiveness of a 10-percent-chord plain flap on the NACA 65-210 airfoil section. The results include an indication of the lift-producing characteristics and the effectiveness of the 10-percent-chord flap. From a comparison of the characteristics of the 10-percent-chord flap with those of a 20-percent-chord flap it was concluded that, although a reduction in flap-chord ratio from 0.20 to 0.10 lessens the severity… more
Date: June 14, 1948
Creator: Ilk, Richard J.
Item Type: Refine your search to only Report
open access

The Effects of Aerodynamic Heating and Heat Transfer on the Surface Temperature of a Body of Revolution in Steady Supersonic Flight

Description: "An approximate method for determining the convective cooling requirement in the laminar boundary-layer region of a body of revolution in high-speed flight was developed and applied to an example body. The cooling requirement for the example body was determined as a function of Mach number, altitude, size, and a surface-temperature parameter. The maximum value of Mach number considered was 3.0 and the altitudes considered were those within the lower constant-temperature region of the atmosphere… more
Date: October 14, 1946
Creator: Scherrer, Richard
Item Type: Refine your search to only Report
open access

The Effects of Horizontal-Tail Location and Wing Modifications on the High-Speed Stability and Control Characteristics of a 01.17-Scale Model of the McDonnell XF2H-1 Airplane (TED No, NACA DE336)

Description: "An additional series of high-speed wind-tunnel tests of a modified 0.17-scale model of the McDonnell XF2H-1 airplane was conducted to evaluate the effects of a reduction in the thickness-to-chord ratios of the tail planes, the displacement of the horizontal tail relative to the vertical tail, and the extension of the trailing edge of the wing. Two tail-intersection fairings designed to improve the flow at the tail were also tested. The pitching-moment characteristics of the model were improved… more
Date: October 14, 1949
Creator: Emerson, Horace F. & Axelson, John A.
Item Type: Refine your search to only Report
open access

Effects of several leading-edge modifications on the stalling characteristics of a 45 degree swept-forward wing

Description: Report presenting an investigation to determine the effects of several leading-edge modifications on the maximum lift and pitching-moment characteristics on a large-scale 45 degree swept-forward wing. A full-span leading-edge flap deflected 30 degrees down tended to give the largest gain of maximum lift. Results regarding the plain leading-edge flaps and cambered nose are explored.
Date: June 14, 1949
Creator: McCormack, Gerald M. & Cook, Woodrow L.
Item Type: Refine your search to only Report
open access

Estimate of Hull-Weight Change with Varying Length-Beam Ratio for Flying Boats

Description: "A study has been made of the variation of seaplane hull weight with length-beam ratio in a systematic series of hulls designed for constant gross weight and similar spray characteristics. It is found that increases in the length-beam ratio bring about small reductions in the hull weight if it is assumed that seaplanes having the same weight and bottom shape will be designed for the same load factor. A short discussion is also given to show the reduction in load factor that may occur with high … more
Date: August 14, 1947
Creator: Benscoter, Stanley U.
Item Type: Refine your search to only Report
open access

Estimation of the forces and moments acting on inclined bodies of revolution of high fineness ratio

Description: Report presenting a discussion of the aerodynamic forces and moments on inclined bodies of revolution. An approximate theory to allow for the effects of viscosity is developed and applied. Results regarding the variation of lift and pitching moment, and center of gravity are provided.
Date: November 14, 1949
Creator: Allen, H. Julian
Item Type: Refine your search to only Report
open access

Evaluation of Gust and Draft Velocities from Flights of P-61C Airplanes Within Thunderstorms September 17, 1946 to September 18, 1946 at Orlando, Florida

Description: The results obtained from measurements of gust velocities, draft velocities, and ambient-air temperature within thunderstorms for the period September 17, 1946 to September 18, 1946 at Orlando, Fla. are presented herein. These data are summarized in tables I, II, and III, respectively, and are of the type presented in reference 1 for previous flights.
Date: March 14, 1947
Creator: Tolefson, H. B.
Item Type: Refine your search to only Report
open access

Experimental investigation of thrust augmentation of 4000-pound-thrust centrifugal-flow-type turbojet engine by injection of water and alcohol at compressor inlets

Description: Report presenting an experimental investigation at zero flight speed and sea-level conditions on a 4000-pound-thrust centrifugal-flow-type turbojet engine to determine the amount of thrust augmentation obtainable at maximum rotor speed by the injection of water, alcohol, and water-alcohol mixtures at the compressor inlets. A maximum thrust augmentation of 26 percent was obtained by the injection of 4.5 pounds per second of water and 2.0 pounds per second of alcohol. Results regarding the tail-p… more
Date: May 14, 1948
Creator: Jones, William L. & Engelman, Helmuth W.
Item Type: Refine your search to only Report
open access

Experimental verification of a simplified vee-tail theory and analysis of available data on complete models with vee tails

Description: An analysis has been made of available data on vee tail surfaces. Previously published theoretical studies of vee tails have been extended to include the control effectiveness and control forces in addition to the stability. Tests of two isolated tail surfaces with various amounts of dihedral provided a check of the theory. Methods for designing vee tails were also developed and are given in the present paper.
Date: November 14, 1944
Creator: Purser, Paul E. & Campbell, John P.
Item Type: Refine your search to only Report
open access

Flight Comparison of Performance and Cooling Characteristics of Exhaust-Ejector Installation with Exhaust-Collector-Ring Installation

Description: Flight and ground investigations have been made to compare an exhaust-ejector installation with a standard exhaust-collector-ring installation on air-cooled aircraft engines in a twin-engine airplane. The ground investigation allowed that, whereas the standard engine would have overheated above 600 horsepower, the engine with exhaust ejectors cooled at take-off operating conditions at zero ram. The exhaust ejectors provided as much cooling with cowl flaps closed as the conventional cowl flaps i… more
Date: February 14, 1947
Creator: Acker, Loren W. & Kleinknecht, Kenneth S.
Item Type: Refine your search to only Report
open access

Flight Investigation of a 20-Inch-Diameter Steady-Flow Ram Jet

Description: Memorandum presenting a flight investigation conducted on a 20-inch-diameter steady-flow ramjet at a range of altitudes and free-stream Mach numbers. Results regarding the variation of combustion efficiency with fuel-air ratio and pressure altitude, effects of combustion-chamber-inlet velocity, and altitude on the operating range of fuel-air ratio are provided. The ramjet unit operated smoothly over the entire range of velocities and altitudes with the exception of occasional rough operation at… more
Date: January 14, 1948
Creator: Disher, John H.
Item Type: Refine your search to only Report
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