Book Description

With ever increasing maturity in the field of subsonic aircraft design, there exists the desire to tailor the performance of an aircraft to suit specific flight conditions. This has led to several adaptive-wing approaches which seek to improve aircraft performance by changing the wing shape in flight, resulting in drag reduction. One such adaptive-wing approach that has gained considerable popularity is the use of multiple spanwise trailing-edge flaps which are used to optimally distribute the lift of the wing such that drag is minimized. Recent research has been conducted utilizing such a technique applied to an aircraft with a wing-tail configuration and discussed the need to extend these methods to tailless, or all-wing, aircraft, thereby improving design possibilities to include unconventional configurations. The current work explores tailless aircraft configurations which utilize multiple trailing-edge flaps for the purpose of wing adaptation and drag reduction. As with all tailless aircraft design, the trailing-edge flap settings, and thus wing lift distribution, must be solved while satisfying a longitudinal-pitching-moment constraint in order to ensure longitudinal stability and trim. This is due to the lack of a secondary horizontal surface, such as a tail or canard, which is typically used for stability and trim purposes. The current work implements a numerical approach which was developed to solve for the optimal flap scheduling of a wing with multiple trailing-edge flaps for various flight conditions. Theory presented by R.T. Jones was used as a starting point to solve for the target lift distribution resulting in minimized induced drag with a pitching moment constraint. Also utilized were the ideas of basic and additional lift, as well as thin airfoil theory relations in order to reduce both induced and profile drag by the redistribution of wing lift along its span. The cases were solved with longitudinal trim and lift constraints. The results were pres.