Technical Report Archive and Image Library (TRAIL) - 1,035 Matching Results

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Aerodynamic characteristics at subcritical and supercritical Mach numbers of two airfoil sections having sharp leading edges and extreme rearward positions of maximum thickness

Description: From Introduction: "A 12-percent-chord-thick wedge section and a reversed NACA 0012 section were chosen for these tests as they are representative of sections having no boat tailing and appreciable boat tailing (i.e., blunt and rounded trailing edges, respectively), and the results of this investigation are compared with those obtained from a previous investigation of the NACA 0012 section. Conclusions are drawn regarding the relative merits of the two unconventional sections and the conventional section in transonic speed range."
Date: November 6, 1947
Creator: Eggers, A J , Jr
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics at subsonic and supersonic Mach numbers of a thin triangular wing of aspect ratio 2 I : maximum thickness at 20 percent of the chord

Description: From Summary: "This report presents the results of a wind-tunnel investigation conducted to determine the effects of Mach number on the aerodynamic characteristics of a wing of triangular plan form."
Date: November 19, 1948
Creator: Berggren, Robert E & Summers, James L
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics at subsonic and supersonic Mach numbers of a thin triangular wing of aspect ratio 2 II : maximum thickness at midchord

Description: The lift, drag, and pitching-moment characteristics of a triangular wing, having an aspect ratio of 2 and a symmetrical double-wedge profile of 5-percent-chord maximum thickness at midchord, have been evaluated from wind-tunnel tests at Mach numbers from 0.50 to 0.975 and from 1.09 to 1.49 and at Reynolds numbers ranging from 0.67 to 0.85 million. The lift, drag, and pitching-moment coefficients of the triangular wing with a leading-edge sweepback of approximately 63 degrees did not exhibit the irregular variations with Mach number at high subsonic and low supersonic Mach numbers that are characteristic of unswept wings. The lift-curve slope increased steadily with Mach number below unity and declined slowly beyond the Mach number of 1.13. A substantial rise in the minimum drag coefficient occurred between Mach numbers of 0.95 and 1.20 with an associated reduction in the maximum lift-drag ratio. The aerodynamic center shifted rearward toward the centroid of area of the wing with increasing Mach number below 0.975; whereas above 1.09 it coincided with the centroid.
Date: December 3, 1948
Creator: Walker, Harold J & Berggren, Robert E
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of a 0.5-Scale Model of the Fairchild XSAM-N-2 Lark Missile at High Subsonic Speeds

Description: An investigation was conducted to determine the longitudinal- and lateral-stability characteristics of a 0.5-scale moue1 of the Fairchild Lark missile, The model was tested with 0 deg and with 22.5 deg of roll. Three horizontal wings having NACA 16-009, 16-209, and 64A-209 sections were tested. Pressures were measured on both pointed and blunt noses. The wind-tunnel-test data indicate that rolling the missile 22.5 deg. had no serious effect on the static longitudinal stability. The desired maneuvering acceleration could not be attained with any of the horizontal wings tested, even with the horizontal wing flaps deflected 50 deg. The flaps on the 64A-209 wing (with small trailing-edge angles and flat sides) were effective at all flap deflections, while the flaps on the 16-series wings (with large trailing-edge angles) lost effectiveness at small flap deflections. The data showed that rolling moment existed when the vertical wing flaps were deflected with the model at other than zero angle of attack. A similar rolling moment probably would be found . with the horizontal wing flaps deflected and the model yawed.
Date: September 28, 1949
Creator: Martin, Andrew & Hunter, Harlo A.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a 6-percent-thick symmetrical double-wedge airfoil at transonic speeds from tests by the NACA wing-flow method

Description: From Introduction: "The investigation covered a range of Mach numbers from 0.66 to 1.12 and included measurements of angle of attack, pitching moment, normal force, and chord force. The drag at zero lift obtained in this investigation was reported in reference 1, but without the correction for tare of the end plate."
Date: March 4, 1949
Creator: Lina, Lindsay J
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a 45 degree swept-back wing with aspect ratio of 3.5 and NACA 2S-50(05)-50(05) airfoil sections

Description: From Introduction: "The present paper presents the scale effect on the longitudinal aerodynamic characteristics, the aerodynamic characteristics in yaw, and the tuft studies for 0^o and 3.7^o yaw. The results of the effect of leading-edge and trailing-edge flaps on the aerodynamic characteristics of the wing will be presented in later reports."
Date: August 4, 1947
Creator: Proterra, Anthony J
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a flying-boat hull having a length-beam ratio of 15 and a warped forebody

Description: From Introduction: "The results of two phases of this investigation, presented in references 1 and 2, have indicated possible ways of reducing hull drag without causing large changes in aerodynamic stability and hydrodynamic performance."
Date: February 11, 1949
Creator: Macleod, Richard G
Partner: UNT Libraries Government Documents Department

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 G.
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of a Portion of the Horizontal Tail from a Douglas C-74 Airplane with Fabric-Covered Elevators

Description: A Douglas C-74 airplane, during a test dive at about 0.525 Mach number, experienced uncontrollable longitudinal oscillations sufficient to cause shedding of the outer wing panels and the subsequent crash of the airplane. Tests of a section of the horizontal tail plane from a C-74 airplane were conducted in the Ames 16-foot high-speed wind tunnel to investigate the possibility of the tail as a contributing factor to the accident. The results of the investigations of fabric-covered elevators in various conditions of surface deformation are presented in this report.
Date: May 6, 1947
Creator: Perone, Angelo & Berthold, Cecil L.
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a wing with quarter-chord line swept back 35 degrees, aspect ratio 4, taper ratio 0.6, and NACA 65A006 airfoil section : transonic-bumb method

Description: From Introduction: "This paper presents the results of the investigation of wing-alone and wing-fuselage combinations employing a wing with the quarter-chord line swept back 35^o, aspect ratio 4, taper ratio 0.6, and NACA 65A006 airfoil section."
Date: April 21, 1949
Creator: Sleeman, William C , Jr & Becht, Robert E
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a wing with quarter-chord line swept back 60 degrees, aspect ratio 4, taper ratio 0.6, and NACA 65A006 airfoil section : transonic-bump method

Description: From Introduction: "This paper presents the results of the investigation of the wing-alone and wing-fuelage configurations employing a wing with the quarter-chord line swept back 60^o, aspect ratio 4, taper ratio 0.6, and an NACA 65A006 airfoil section parallel to the free stream."
Date: September 6, 1949
Creator: King, Thomas J , Jr & Myers, Boyd C , II
Partner: UNT Libraries Government Documents Department

Aerodynamic characteristics of a wing with unswept quarter-chord line, aspect ratio 4, taper ratio 0.6, and NACA 65A006 airfoil section

Description: From Introduction: "This paper presents the results of the investigation of the wing-alone and of the wing-fuselage configuration employing a wing with an unswept quarter-chord line, aspect ratio 4, taper ratio 0.6, and an NACA 65A006 airfoil section parallel to the air stream. The results of closely related sweptback-wing investigations, which are part of the present transonic programs, are presented in references 1 to 3."
Date: October 21, 1949
Creator: Goodson, Kenneth W & Morrison, William D , Jr
Partner: UNT Libraries Government Documents Department

Aerodynamic Characteristics of Three Deep-Stepped Planing-Tail Flying-Boat Hulls

Description: An investigation was made in the Langley 300 MPH 7- by 10-foot tunnel to determine the aerodynamic characteristics of three deep-stepped planing-tail flying-boat hulls differing only in the amount of step fairing. The hulls were derived by increasing the unfaired step depth of a planing-tail hull of a previous aerodynamic investigation to a depth about 92 percent of the hull beam. Tests were also made on a transverse-stepped hull with an extended afterbody for the purpose of comparison and in order to extend and verify the results of a previous investigation. The investigation indicated that the extended afterbody hull had a minimum drag coefficient about the same as a conventional hull, 0.0066, and an angle-of-attack range for minimum drag coefficient of 0.0057 which was 14 percent less than the transverse stepped hull with extended afterbody; the hulls with step fairing had up to 44 percent less minimum drag coefficient than the transverse-stepped hull, or slightly more drag than a streamlined body having approximately the same length and volume. Longitudinal and lateral instability varied little with step fairing and was about the same as a conventional hull.
Date: March 13, 1947
Creator: Riebe, John M. & Naeseth, Rodger L.
Partner: UNT Libraries Government Documents Department