Spectroscopic filter arrays and methods for making spectroscopic filter arrays are provided. A flex circuit is inserted in part between ICs to be stacked and provides a connective field that provides plural contact areas that connect to respective leads of the ICs. Thus, in an impact situation in which the fan blade has separated from the fan rotor and the fan blade has itself separated into fragments, the root part will fracture or buckle more easily than would be the case with conventional arrangements.