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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
Item Type: Report

Aerodynamic Characteristics in Pitch and Sideslip at High Subsonic Speeds of a 1/14-Scale Model of the Grumman XF104 Airplane with Wing Sweepback of 42.5 Degrees

Description: An investigation has been made at high subsonic speeds of the aerodynamic'characteristics in pitch and sideslip of a l/l4-scale model of the Grumman XF10F airplane with a wing sweepback angle of 42.5. The longitudinal stability characteristics (with the horizontal tail fixed) indicate a pitch-up near the stall; however, this was somewhat alleviated by the addition of fins to the side of the fuselage below the horizontal tail. The original model configuration became directionally unstable for small sideslip angles at Mach numbers above 0.8; however, the instability was eliminated by several different modifications.
Date: 1953~
Creator: Kuhn, Richard E. & Draper, John W.
Item Type: Report

The Aerodynamic Characteristics in Pitch of a 1/15-Scale Model of the Grumman F11F-1 Airplane at Mach Numbers of 1.41, 1.61, and 2.01, TED No. NACA DE 390

Description: Tests have been made in the Langley 4- by 4-foot supersonic pressure tunnel at Mach numbers of 1.41, 1.61, and 2.01 to determine the static longitudinal stability and control characteristics of various arrangements of the Grumman F11F-1 airplane. Tests were made of the complete model and various combinations of its component parts and, in addition, the effects of various body modifications, a revised vertical tail, and wing fences on the longitudinal characteristics were determined. The results indicate that for a horizontal-tail incidence of -10 deg the trim lift coefficient varied from 0.29 at a Mach number of 1.61 to 0.23 at a Mach number of 2.01 with a corresponding decrease in lift-drag trim from 3.72 to 3.15. Stick-position instability was indicated in the low-supersonic-speed range. A photographic-type nose modification resulted in slightly higher values of minimum drag coefficient but did not significantly affect the static stability or lift-curve slope. The minimum drag coefficient for the complete model with the production nose remained essentially constant at 0.047 throughout the Mach number range investigated.
Date: May 23, 1956
Creator: Driver, Cornelius
Item Type: Report