Accession Number : AD0719742

Title :   Nonlinear Vortex Interactions on Wing-Canard Configurations,

Corporate Author : FRANK J SEILER RESEARCH LAB UNITED STATES AIR FORCE ACADEMY COLO

Personal Author(s) : Finkleman,David

Report Date : FEB 1971

Pagination or Media Count : 17

Abstract : Close-coupled wing-canard configurations are ideally suited to applications in which high aircraft maneuverability is required at moderate speeds. The SAAB Viggen has exploited the advantages of placing canard and wing close together, but no theory has been capable of predicting the aerodynamics of this aircraft. In this investigation Sacks' method of simulating vortex sheets with distributions of discrete vortices has been applied to the study of the interaction of a slender wing with a nearly canard surface. The canard is detrimental to both lift and static longitudinal stability. The extent of canard wake roll-up is important in the interaction, and the flatter the wake the more adverse is the interaction. Downward canard deflection may lead to increases in lift of the entire configuration, and it is observed that for small vertical separations between the surfaces the forward portion of the wing is ineffective in producing lift. It is demonstrated that the canard can directly affect the pressure distribution on the wing and application of this configuration to direct lift control and control configured aircraft are noted. (Author)

Descriptors :   (*CANARD CONFIGURATION, LIFT), (*SHORT TAKEOFF AIRCRAFT, AERODYNAMIC CHARACTERISTICS), THIN WINGS, VORTICES, MANEUVERABILITY, MATHEMATICAL MODELS, STABILITY, PRESSURE, WAKE

Subject Categories : V/STOL
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE