A phased array sensor assembly is presented that can be permanently adhered to and impart ultrasonic waves to a structural surface and receive ultrasonic waves from a structural surface. The sensor assembly includes piezo-electric disks, a plurality of electrically conductive epoxy film adhesive contacts positioned such that an electrical coupling is formed with the piezo-electric disks, piezo transducer flex wire trace circuits aligned to be electrically coupled respectively with the electrically conductive epoxy film adhesive contacts on one end and including a plurality of wire trace electrical contact pads on the other end, and a flexible polyimide layer. The polyimide layer includes laser ablated areas for exposing the contact pads such that they can be electrically coupled with an external device.