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.

An analysis of the effects of canard size, 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 the findings of four experimental subsonic wind-tunnel programs conducted at the David W. Taylor Naval Ship Research and Development 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 located at seven different positions and deflected from -10 to 25 degrees. Significant findings include: the excellent correlation between canard exposed area ratio and changes in lift, drag, and pitching moment; the deterimental effect of positive canard deflection; and the optimum longitudual position for each canard shape for maximum improvements in lift and drag. It is further concluded that the favorable aerodynamic changes caused by interference of the close-coupled canard are not significantly dependent on wing leading edge sweep or wing leading edge modifications.

A summary of the general findings of close-coupled canard research at David W. Taylor Naval Ship Research and Development Center is presented. These findings are based on a series of wind-tunnel evaluations utilizing an aircraft research model having wings of either 25- or 50-degree leading edge sweep. Discussed is the effect of canard placement on lift, drag, and pitching moment and the location of optimum position for canards of different planform. In addition, the effects of canard-wing interference, canard deflection, size, and Mach number are described.

The use of close-coupled canards to improve the flight characteristics of fighter and attack aircraft is currently being proposed. This report presents test data on the effect of such canards on a 25 deg leading edge sweep wing mounted low on a generalized body. The parameters investigated were canard deflection and position with the aircraft configured with and without a horizontal tail.