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The Prospects for Laminar Flow on Hypersonic Airplanes

Description: The factors which affect the extent of laminar flow on airplanes for hypersonic flight are discussed on the basis of the available data. Factors considered include flight Reynolds number, surface roughness, angle of attack, angle of leading-edge sweepback, and aerodynamic interference. Test data are presented for one complete configuration.
Date: June 27, 1958
Creator: Seiff, Alvin
Partner: UNT Libraries Government Documents Department
open access

Lift, Drag, and Pitching Moment of Low-Aspect-Ratio Wings at Subsonic and Supersonic Speeds: Plane Triangular Wing of Aspect Ratio 3 With Air-to-Air Missile Models Mounted Externally

Description: "This report presents results of an investigation of effects of externally mounted missile models on the aerodynamic characteristics of a triangular wing of aspect ratio 3 at both subsonic and supersonic Mach numbers. The lift, drag, and pitching moment of the wind-fuselage model fitted with the missile models are presented for Mach numbers of 0.6, 0.9, 1.2, 1.4, and 1.7 at a Reynolds number of 4.8 million. Similar data are presented for the basic wing" (p. 1).
Date: June 26, 1952
Creator: Conrard, Donald
Partner: UNT Libraries Government Documents Department
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Theoretical Investigation of the Performance of Proportional Navigation Guidance Systems: Effect of Missile Configuration on the Speed of Response

Description: Memorandum presenting a comparison of the maximum speed of response that can be attained by three missile configurations, a variable-incidence-wing, a canard, and a tail-control, in combination with a particular proportional navigation guidance system. The configuration that allows the most rapid overall guidance-system response depends on the control-system characteristics. Results regarding the rate-only feedback and rate and normal acceleration feedback are provided.
Date: January 19, 1953
Creator: Abramovitz, Marvin
Partner: UNT Libraries Government Documents Department
open access

On the Use of the Indicial-Function Concept in the Analysis of Unsteady Motions of Wings and Wing-Tail Combinations

Description: "The concept of indicial aerodynamic functions is applied to the analysis of the short-period pitching mode of aircraft. By the use of simple physical relationships associated with the indicial-function relationships concept, quantitative studies are made of the separate effects on the damping in pitch of changes in Mach number, aspect ratio, plan-form shape, and frequency. The concept is further shown to be of value in depicting physically the induced effects on a tail surface which follows in… more
Date: 1954
Creator: Tobak, Murray
Partner: UNT Libraries Government Documents Department
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The effect of compressibility on two-dimensional tunnel-wall interference for a symmetrical airfoil

Description: Summary: The effective change in the velocity of flow past a wing section, caused by the presence of wind-tunnel walls, is known for potential flow. This theory is extended by investigation of the two-dimensional compressible flow past a thin Rankine Oval. It is shown that for a symmetrical section at zero angle of attack the velocity increment due to the tunnel walls in the incompressible case must be multiplied by the factor 1/1-M^2 to take account of compressibility effects. The Mach numb… more
Date: May 1943
Creator: Nitzberg, Gerald E.
Partner: UNT Libraries Government Documents Department
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Tests of a Thermal Ice-Prevention System for a Wing Leading-Edge Landing-Light Installation

Description: Report discussing the creation of a thermal ice-prevention system of a bomber-type airplane to provide protection against ice and fog formations on the transparent fairing over the landing light in the wing leading edge. A comparison between the design performance and actual performance showed that the outer-surface heat-transfer coefficient was correctly predicted, but the inner-surface heat-transfer coefficient was four times as large, leading to failure of the plastic fairing.
Date: December 1944
Creator: Hillendahl, Wesley H.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation of the Effects of Spoilers on the Characteristics of a Low-Drag Airfoil Equipped With a 0.25-Chord Slotted Flap

Description: Report discussing the effects of circular-arc spoilers on the section characteristics of an NACA 66,2-216 airfoil with a 0.25-chord slotted flap. Spoilers were tested on the upper surface of the airfoil, on the lower surface, and on both simultaneously. Only the simultaneous placement of spoilers was found to provide satisfactory results as a lateral control device.
Date: July 23, 1945
Creator: Holtzclaw, Ralph W.
Partner: UNT Libraries Government Documents Department
open access

A Concise Theoretical Method for Profile-Drag Calculation; Advance Report

Description: In this report a method is presented for the calculation of the profile drag of airfoil sections. The method requlres only a knowledge of the theoretical velocity distribution and can be applied readily once this dlstribution is ascertained. Comparison of calculated and experimental drag characteristics for several airfoils shows a satisfactory agreement. Sample calculatlons are included.
Date: February 1944
Creator: Nitzberg, Gerald E.
Partner: UNT Libraries Government Documents Department
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Compressible potential flow with circulation about a circular cylinder

Description: Report presenting the potential function for flow, with circulation, of a compressible fluid about a circular cylinder, which is obtained in series form including terms of the order of M(exp 4) where M is the Mach number of the free stream. The equations are used to obtain pressure coefficient as a function of Mach number at a point on the surface of the cylinder for different values of circulation.
Date: January 1944
Creator: Heaslet, Max A.
Partner: UNT Libraries Government Documents Department
open access

Notes on the Effect of Surface Distortions on the Drag and Critical Mach Number of Airfoils

Description: "The effect of two-dimensional bumps and surface waviness on the pressure distribution over airfoils is considered. It is shown that the results of the analysis may be useful in evaluating the effects of accidental or intended surface distortions on the drag and critical Mach number of airfoils" (p. 1).
Date: September 1943
Creator: Allen, H. Julian
Partner: UNT Libraries Government Documents Department
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Effect of the Performance of a Turbosupercharged Engine of an Exhaust-Gas-to-Air Heat Exchanger for Thermal Ice Prevention

Description: This report presents the results of a flight investigation to determine the effect on the performance of a turbosupercharged engine of an exhaust-gas-to-air heat exchanger installed between the engine-exhaust collector ring and the turbosupercharger. The background, results, and discussion of the investigation are described.
Date: August 23, 1945
Creator: Look, Bonne C.
Partner: UNT Libraries Government Documents Department
open access

Corrosion tests of a heated wing utilizing an exhaust-gas-air mixture for ice prevention

Description: Report presenting an investigation of the exhaust of corrosive attack in an aluminum alloy wing employing an exhaust-gas-air mixture as a heating medium for ice prevention. There were no cases of structurally serious corrosion on either painted or plain specimens removed from the wing for detailed microscopic and metallurgic examination.
Date: January 1949
Creator: Holdaway, George H.
Partner: UNT Libraries Government Documents Department
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Experimental Verification of Two Methods for Computing the Take-Off Ground Run of Propeller-Driven Aircraft

Description: Note presenting a comparison between the measured take-off ground run of an airplane equipped with seven different propeller-engine gear-ratio combinations and the computed distances by two different methods. Results indicated that the values of ground run calculated by Diehl's approximate method checked experimental values with 7 percent but were in error as much as 10 to 15 percent under certain conditions. Improved methods of thrust computation may be required in order to avoid large errors … more
Date: June 1947
Creator: Gasich, Welko E.
Partner: UNT Libraries Government Documents Department
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Wind-Tunnel Investigation at Low Speed of a Wing Having 63 Degree Sweepback and a Drooped Tip

Description: From Summary: "The results of force tests made at low speed are presented to show the effect of longitudinal static stability produced by drooping the tip of a 63 degree sweptback wing. Five semispan wing models were tested: two incorporated curved drooped tips, two with abruptly drooped tips, and one without droop. The most favorable stability characteristics were measured for a model with an abruptly drooped tip, a fence, and a leading-edge flap; however, the use of these same auxiliary devic… more
Date: April 7, 1955
Creator: Blackaby, James R.
Partner: UNT Libraries Government Documents Department
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The High-Speed Characteristics of Several Flaps and Spoilers on the Upper Surface of the Horizontal Stabilizer of a Model of a Radial-Engine Pursuit Airplane

Description: Report discussing an investigation into several types and sizes of flaps and spoilers located forward of the elevators on the upper surface of the horizontal stabilizer of a model of a radial-engine pursuit airplane. Information about the elevator characteristics, elevator-fixed and elevator-free balance lift coefficient, and trim drag coefficient for a range of Mach numbers is provided.
Date: January 21, 1946
Creator: Boddy, Lee E.
Partner: UNT Libraries Government Documents Department
open access

An experimental investigation of two methods for reducing transonic drag of swept-wing and body combinations

Description: Report presenting an investigation of a wing swept back 35 degrees in combination with one basic body and three modified bodies at a range of Mach numbers from 0.60 to 1.20. Results regarding force studies and pressure studies are provided. The bodies modified according to the Kuchenmann ring-vortex method resulted in superior aerodynamic characteristics except with regard to zero-lift drag at high supersonic Mach numbers.
Date: April 29, 1955
Creator: McDevitt, John B.
Partner: UNT Libraries Government Documents Department
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A Comparison of Two Flight-Test Procedures for the Determination of Aileron Control Capabilities of an Airplane

Description: Report presenting a comparison of two flight-test procedures for the determination of the aileron control capabilities of an airplane. The procedures consist of performing rudder-fixed aileron rolls from straight unbanked flight and from steady turning flight. Results regarding rate of roll comparison and sideslip-angle comparison are provided.
Date: July 1945
Creator: Skoog, Richard B.
Partner: UNT Libraries Government Documents Department
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Comparison Between Analytical and Wind-Tunnel Results on Flutter of Several Low-Aspect-Ratio, High-Density, Unswept Wings at High Subsonic Speeds and Zero Angle of Attack

Description: Memorandum presenting experimental flutter Mach numbers for several solid, thin, rectangular cantilever wings with uniform section properties, low aspect ratio, and high relative density estimated from the results of previous tests at zero angle of attack. The experimental values are considered estimates, rather than determinations, in the high subsonic speed range because in that range the amplitude criterion was necessarily arbitrary. Results regarding conservatism of standard analysis relati… more
Date: September 20, 1955
Creator: Warner, Robert W.
Partner: UNT Libraries Government Documents Department
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Theoretical investigation of the effects of configuration changes on the center of pressure shift of a body-wing-tail combination due to angle of attack and Mach number at transonic and supersonic speeds

Description: Report presenting a theoretical investigation to study the effects of systematic changes in configuration of a representative airframe on the center-of-pressure travel due to changes in angle of attack and in Mach number. The airframe was an unbanked canard missile configuration with low-aspect-ratio coplanar wing and tail surfaces of triangular plan form. Results regarding the center-of-pressure shift due to angle of attack, center-of-pressure shift due to Mach number, and combined effects of … more
Date: September 2, 1955
Creator: Spahr, J. Richard
Partner: UNT Libraries Government Documents Department
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An investigation of string support interference on base pressure and forebody chord force at Mach numbers from 0.60 to 1.30

Description: Report presenting testing to determine the interference effects of various sting-support configurations on the base pressure and foredrag characteristics of a wing-fuselage combination with a turbulent boundary layer. The primary variable investigated was the length of the constant-diameter portion of a sting support. Results regarding the base-pressure interference and foredrag interference are provided.
Date: January 28, 1955
Creator: Tunnell, Phillips J.
Partner: UNT Libraries Government Documents Department
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A flight investigation at transonic speeds and small angles of attack of the aerodynamic characteristics of a model having a 45 degree sweptback wing of aspect ratio 3 with an Naca 64A006 airfoil section

Description: Report presenting an investigation of the longitudinal aerodynamic characteristics of a model with a 45 degree sweptback wing of aspect ratio 3 and a 45 degree sweptback cruciform tail at transonic speeds and small angles of attack by a free-fall recoverable-model technique. Results regarding lift, drag, static longitudinal stability, dynamic longitudinal stability, and loading distribution over the fuselage are provided.
Date: January 25, 1954
Creator: Holdaway, George H.
Partner: UNT Libraries Government Documents Department
open access

Wind-tunnel investigation of the effect of clipping the tips of triangular wings of different thickness, camber, and aspect ratio - transonic bumb method

Description: Report presenting an investigation on a transonic bump to determine the aerodynamic characteristics of a series of triangular wings. Four basic triangular-wing plan forms with different aspect ratios, taper ratios, and combinations of tip clipping were tested over a range of Mach and Reynolds numbers. Results regarding angle of attack, drag coefficient, pitching-moment coefficient with lift coefficient, and various curves are provided.
Date: February 3, 1954
Creator: Emerson, Horace F.
Partner: UNT Libraries Government Documents Department
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