FBS proposes a novel hybrid ultrasonic guided wave technique that combines guided wave circular array technology with the nonlinear characteristics of guided waves for the SHM of microcracks in complex composite structure components in spacecraft and launch vehicles. The technique is aimed at providing a reliable, robust, rapid, flexible as well as cost effective SHM solution for spacecraft structures. The applications of the proposed technique, if successful, can lead to remarkable contributions to the inspection and maintenance of NASA spacecraft and launch vehicles. As compared to other currently in-use spacecraft inspection methods, our product can save a large amount of spacecraft maintenance time and cost due to the fact that our technique has the capability of monitoring large areas and hidden structures from limited accessible positions and characterizing microcracks in the mean time. The technique not only fits the needs of the on inspecting spacecraft structures, but also has the potential to be applied to almost any industrial or mechanical engineering system containing plate-like structures. The proposed technology is applicable for both metal and composite materials. It is sensitive to micro-damages in these materials and is capable of inspecting a large area from very limited accessible positions. The proposed technology can be slightly modified to be used on large tanks, ship hulls, as well as aircraft structures.