Description: Under this collaborative effort, Creative Aero Engineering Solutions (CAES) and its partner, Wyle Laboratories, will integrate within our MDO framework the latest development of the three zone method, which is expected to eliminate the need for far-field results beyond 25 spans that typical Sonic-Boom prediction two-zone methods currently use. We will use the adjoint solution of the near-field pressure functional of the flowfield (more specifically sonic boom related functionals) to create new design variables, which will better characterize the design space more accurately and allow for more efficient low-boom configuration design. Subsequently, a similar methodology can be utilized for trajectory optimization (i.e. avoidance of focused booms at certain locations) during climb and descent of typical supersonic aircraft. We will use a different set of variables for such purposes (i.e. control surface deflections/thrust schedules). During Phase I we will establish the feasibility of the three zone approach within our MDO framework and verify the functionality of the design variables. Under Phase II, we will apply the new methodology to a NASA Low Boom configuration.

Benefits: The developed capability will allow NASA analysts to effectively couple an efficient procedure to characterize the design space of a low-boom supersonic transport with a very badly needed multizone method for the prediction of focused ground boom signatures and/or their mitigation maneuvers. Our team truly believes that the three zone method will allow NASA to focus more on the "nearfield" nature of the CFD flowfield (i.e. propulsion plumes with shocks and expansions) and less on requiring grid convergence studies for 2 to 20 body lengths in order to achieve proper ground signature predictions. Potential other NASA applications include the accurate prediction of a focused boom of an accelerating launch vehicle of a supersonic fighter jet. With commercial launches becoming more safe and commonplace (i.e. SpaceX and Orbital Sciences), one may expect closer proximity to inhabited zones in the future and therefore more accurate focused boom prediction. Finally, capsule reentry booms (i.e. Orion) will eventually need to be more accurately predicted as manned spaceflight becomes commonplace.

Ultimately, the primary non-NASA application will involve more accurate prediction of "boom" footprints of supersonic fighters being operated by Air-Forces around the world. Moreover, AFRL could use this technology for the design of its next generation fighters and bombers. Needless to say, when approved for export control (obviously only certain aspects of this technology could be), we will be able to commercialize the capability to numerous companies, including the prime airframers, and allied governments and their respective space agencies.