Manticore
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CANARDS
Modern high-speed aircraft, especially military, are very often equipped with single or compound delta wings. When such aircraft operate at high angles-of-attack, the major portion of the lift is sustained by streamwise vortices generated at the leading edges of the wing. This vortex-dominated flow field can breakdown, leading not only to loss of lift but also to adverse interactions with other airframe components such as the fin or horizontal tail
The performance of a canard design depends strongly on the amount of lift that the canard must carry. This is set by stability and trim requirements.
An analysis of the effects of canard shape, position, and deflection on the aerodynamic characteristics of two general research models having leading edge sweep angles of 25 and 50 degrees is presented. The analysis summarizes findings of three experimental transonic wind-tunnel programs and one supersonic wind-tunnel program conducted at this Center between 1970 and 1974. The analysis is based on four canard geometries varying in planform from a 60-degree delta to a 25-degree swept wing, high aspect ratio canard. The canards were tested at several positions and deflected from -10 to +10 degrees. In addition, configurations consisting of a horizontal tail and a canard with horizontal tails are analyzed. Results of the analysis indicate that the canard is effective in increasing lift and decreasing drag at Mach numbers from subsonic to high transonic speeds by delaying wing separation. The effectiveness of the canard is, however, decreased with increasing Mach number. At supersonic speeds the canard has little or no favorable effects on lift or drag. It is further shown that the horizontal tail is a superior trimming device than the close- coupled canard at low-to-moderate angles of attack and that a configuration consisting of canard, wing, and horizontal tail is superior in performance, to either canard or horizontal tail at high angles of attack.
The Canards in the Lavi have also dihedral but also they are far too close to the wings in fact over them-- The Eurofighter`s are not as close to the wings as those on the Lavi, the position has to do with drag/lift ratio, the best combination is high aspect canards low aspect wings check the Eurofighter has also strakes -- chinese J-10 also the canards are not too far from the wing, however are not so close as those in the Lavi and Rafale, both the Eurofighter and J-10 have the least drag canard delta wing configuration specially good for a fast aircraft -- the Viggen has low aspect wings and canards, these low aspect canards and wing are best configured for high lift
Modern high-speed aircraft, especially military, are very often equipped with single or compound delta wings. When such aircraft operate at high angles-of-attack, the major portion of the lift is sustained by streamwise vortices generated at the leading edges of the wing. This vortex-dominated flow field can breakdown, leading not only to loss of lift but also to adverse interactions with other airframe components such as the fin or horizontal tail
The performance of a canard design depends strongly on the amount of lift that the canard must carry. This is set by stability and trim requirements.
An analysis of the effects of canard shape, position, and deflection on the aerodynamic characteristics of two general research models having leading edge sweep angles of 25 and 50 degrees is presented. The analysis summarizes findings of three experimental transonic wind-tunnel programs and one supersonic wind-tunnel program conducted at this Center between 1970 and 1974. The analysis is based on four canard geometries varying in planform from a 60-degree delta to a 25-degree swept wing, high aspect ratio canard. The canards were tested at several positions and deflected from -10 to +10 degrees. In addition, configurations consisting of a horizontal tail and a canard with horizontal tails are analyzed. Results of the analysis indicate that the canard is effective in increasing lift and decreasing drag at Mach numbers from subsonic to high transonic speeds by delaying wing separation. The effectiveness of the canard is, however, decreased with increasing Mach number. At supersonic speeds the canard has little or no favorable effects on lift or drag. It is further shown that the horizontal tail is a superior trimming device than the close- coupled canard at low-to-moderate angles of attack and that a configuration consisting of canard, wing, and horizontal tail is superior in performance, to either canard or horizontal tail at high angles of attack.
The Canards in the Lavi have also dihedral but also they are far too close to the wings in fact over them-- The Eurofighter`s are not as close to the wings as those on the Lavi, the position has to do with drag/lift ratio, the best combination is high aspect canards low aspect wings check the Eurofighter has also strakes -- chinese J-10 also the canards are not too far from the wing, however are not so close as those in the Lavi and Rafale, both the Eurofighter and J-10 have the least drag canard delta wing configuration specially good for a fast aircraft -- the Viggen has low aspect wings and canards, these low aspect canards and wing are best configured for high lift
