No airplane is complete with fasteners. Depending on the size, airplanes may contain anywhere from 1 million to 3 million fasteners. Each of these fasteners is responsible for holding one or more parts in place. In addition to traditional fasteners, though, most airplanes feature blind fasteners.
What Are Blind Fasteners?
Blind fasteners are bolts, rivets and other fastening hardware that are designed for use in passages that are only accessible from a single side. You don’t have to access both sides of a given passage to install them.
They are known as “blind fasteners” because they only require access to a single side, such as the front. You can typically install them by only accessing the front of a passage or hole. Even if you can’t see the back side of a passage, it will likely support a blind fastener.
How Blind Fasteners Work
Different types of blind fasteners work in different ways. There are blind rivets, for instance, that expand when placed inside of a passage. They require the use of a tool to install. To install a blind rivet, you’ll need to place the assembly into a passage, after which you can use a tool to pull the mandrel through the blind rivet. This will cause the head of the blind rivet to expand so that it stays in place.
Blind bolts only require access to a single side of the passage as well, but they use a different method of operation than blind bolts. Blind bolts feature three parts: a pin, collar and sleeve. You can place them inside of passages. The collar of a blind bolt is designed to collapse. Upon collapsing, the collar will expand while holding the blind bolt in place.
Why Airplanes Feature Blind Fasteners
Airplanes feature blind fasteners for several reasons, one of which is the simple fact that they are easier to install than traditional fasteners. Traditional fasteners may require access to the back side of a passage. When assembling an airplane, aerospace manufacturers may only have access to the front side of certain passages. As a result, blind fasteners are commonly used.
Blind fasteners are also resistant to vibrations. Other types of fasteners may loosen when exposed to vibrations, which can jeopardize the airplane’s structural integrity. Blind fasteners, on the other hand, are resistant to vibrations. Both blind rivets and blind bolts will collapse during installation, thus offering a more secure hold.