Update of Composite Fastener Technology at BHTI

Composite fasteners are of great interest to the aircraft industry as an improved method for joining composite structure. Current metal-fastener technology does not adequately address all the relevant concerns, problems that contribute to increased costs, weight, and radar signature. Emerging composite fastener technology offers the potential of alleviating some of these problems. Preliminary data on polyetheretherketone (PEEK) continuous carbon fiber fasteners were developed, coupons were tested, data were analyzed, and preliminary design criteria were established to facilitate application to design. These criteria were then utilized to select potential structural elements and components for fastener installation. A test element was identified, fasteners were installed, a static test performed, and fasteners evaluated in aircraft structure. A component was identified, the fasteners were installed in a secondary composite structure, and flight tests were conducted. Results verified that composite fasteners provide an efficient means to lower costs and aircraft weight, and reduce radar signature.