Aircraft Fasteners and their Applications

With every component that comes together to create an aircraft, it is actually one of the smallest components, the fastener, that remains one of the most important parts to the entirety of the structure. A Boeing 747-800, for example, is comprised of 6 million parts, half of them being fasteners. Much like a fastener that one may find at a hardware store, the part’s functionality at its most basic is to join or affix two or more components together in a non-permanent fashion so that the objects could be later separated. Unlike their hardware store counterparts, however, aviation fasteners are held to a much higher standard, and are specifically engineered with precise specifications to ensure they withstand the demands of high altitude flight. Fasteners are important beyond holding components together, also providing the benefit of taking on and redistributing structural loads.

Aviation fasteners come in many types, common examples being screws, bolts, nuts, washers, rivets, and more. They are most often manufactured using metal, namely steel, titanium, aluminum, and alloys depending on the application and conditions they will undertake. Fasteners also are specifically designed with various shapes and heads depending on the utilization as well, and qualities such as the head decides what type of installation is required. Some heads and applications allow for simple hand tools such as a wrench to install correctly, while others may be precisely installed using machines.

With a plethora of fasteners that are being manufactured and entering the commercial market every year, it becomes difficult for the FAA to administer and approve all of them for qualifications such as being a standard part. To remedy this, as well as still maintain quality control of new fasteners, the Fastener Quality Act (FQA) was enacted in 1999. The FQA ensures that manufactured fasteners adhere to precise specifications, laboratories that test fasteners are properly accredited, as well as requiring inspection, testing, and certification for standardization of parts.