Book Description

To identify planform characteristics which have promise for a highly maneuverable vehicle, an investigation was conducted in the Langley Subsonic Basic Research Tunnel to determine the low-speed longitudinal aerodynamics of 21 planform geometries. Concepts studied included twin bodies, double wings, cutout wings, and serrated forebodies. The planform models tested were all 1/4-in.-thick flat plates with beveled edges on the lower surface to ensure uniform flow separation at angle of attack. A 1.0-in.-diameter cylindrical metric body with a hemispherical nose was used to house the six-component strain gauge balance for each configuration. Aerodynamic force and moment data were obtained across an angle-of-attack range of 0 to 70 deg with zero sideslip at a free-stream dynamic pressure of 30 psf. Surface flow visualization studies were also conducted on selected configurations using fluorescent minitufts. Results from the investigation indicate that a cutout wing planform can improve lift characteristics; however, cutout size, shape, and position and wing leading-edge sweep will all influence the effectiveness of the cutout configuration. Tests of serrated forebodies identified this concept as an extremely effective means of improving configuration lift characteristics; increases of up to 25 percent in the value of maximum lift coefficient were obtained. Gatlin, Gregory M. and Mcgrath, Brian E. Langley Research Center AERODYNAMIC CHARACTERISTICS; ANGLE OF ATTACK; FLOW VISUALIZATION; FOREBODIES; HIGHLY MANEUVERABLE AIRCRAFT; LIFT; LOW ASPECT RATIO WINGS; LOW SPEED; PITCHING MOMENTS; SWEPT WINGS; WIND TUNNEL TESTS; WING PLANFORMS; AERODYNAMIC COEFFICIENTS; ARROW WINGS; BOUNDARY LAYER SEPARATION; DELTA WINGS; DUAL WING CONFIGURATIONS; LEADING EDGE SWEEP; OPENINGS; STRAIN GAGE BALANCES; TRAILING EDGES; UNIFORM FLOW...