Designates the basic part number or material (e.g., "BJ" for a specific solid rivet).
The NAS523 Fastener Code is essential because modern aircraft, such as the Boeing 747, can require over 1.8 million fasteners. Without this standardized system, technical drawings would be cluttered with repetitive text. nas523 pdf top
Contains a two- or three-letter code that identifies the fastener part number (such as AN or MS standards) and the material/alloy . For example, the code "BJ" identifies a standard MS20470AD universal-head rivet made of 2117 aluminum alloy. Designates the basic part number or material (e
The code is represented on technical drawings as a four-quadrant "crosshair" symbol. Each quadrant contains specific data that dictates how a technician should install the fastener: such as the Boeing 747