What Are Aerospace Fasteners?

Across aviation, defense, and space programs, the mechanical integrity of any assembled structure hinges on the use of seemingly simple components known as fasteners, which are rarely visible or outwardly noticeable once work is complete. While not always appearing to be as important as major wing structures, onboard electronics, or flight controls, aerospace fasteners are essential for countless workpieces to remain securely together in the face of great operational and environmental stress. As such, procurement professionals and maintenance teams working across aerospace and aviation industries can gain much benefit from understanding the importance of aerospace fasteners and how their selection is governed. For this, we invite you to read on for a clear overview of aerospace fasteners, our blog covering topics ranging from the characteristics that define the broad category of items to the way these components are organized by type and specification.

An Overview of Aerospace Fasteners

Like the hardware found in various other industries and operational settings, aerospace fasteners generally serve the role of joining, securing, or retaining parts for assemblies, either providing permanent or temporary joints. However, unlike basic consumer-level fasteners, the options used for aerospace and aviation purposes are distinguished by the rigorous engineering standards and documentation obligations that have been established by governing and regulatory bodies for performance, safety, and interchangeability. As a result, such components are produced to tight dimensional tolerances and subject to demanding material selection expectations, guaranteeing that they will withstand flight stressors ranging from sustained mechanical loading to thermal cycling.

The Main Types of Aerospace Fasteners

Understanding the common aircraft fastener types that are used within aerospace contexts can help procurement teams identify the right components for many basic assembly requirements. The following constitute some of the most frequently encountered forms of hardware for such operations, where each group has its own unique set of uses, subtypes, etc.

• Bolts and Structural Fasteners: Commonly used at primary load-bearing joints throughout an airframe, aerospace-grade bolts are produced from high-strength alloys like titanium, alloy steel, or corrosion-resistant steel to provide an optimal balance of strength, low-weight construction, and environmental protection. 
• Rivets: As components that permanently join workpieces together, rivets are widely found across aircraft skin panels and internal structural assemblies. Solid-shank rivets are the standard for joints that have both sides accessible during installation, while blind rivets best serve locations where access is limited to a single side.
• Hi-Lok and Lockbolt Fasteners: These two-piece systems pair a pin with a collar to deliver consistent, repeatable clamp loads across high-shear joints. Their controlled installation torque and interference-fit design make them a widely relied-upon choice in airframe manufacturing and depot-level maintenance programs.
• Screws and Close-Tolerance Fasteners: Aerospace screws range from standard machined variations that are used for panel and access cover applications to close-tolerance variants that excel in maintaining joint alignment while limiting movement.
• Nuts, Washers, and Nut Plates: These supporting components often serve load distribution and retention needs, as well as mitigate the risk of fastened assemblies loosening over time. Nut plates are particularly common in assemblies that require repeated disassembly, providing a fixed threaded interface that does not necessitate having access to the back side of a structure for installation.

How Aerospace Fasteners Are Specified and Classified

Aerospace fasteners are governed by a structured body of specifications established by federal organizations, military bodies, and industry committees, with each standard generally defining a required approach to manufacturing and documentation. Procurement teams who understand basic classification frameworks are better positioned to identify the correct item for any need, as well as will have more ease in confirming the validity of the reviewed item to meet requirements. To support such capabilities, buyers should understand the basics of:

• Governing Specification Families: The most common designations that govern fastener design and production include National Aerospace Standards (NAS), Air Force-Navy Aeronautical (AN) Standards, and Military Standards (MS). With a range of specifications existing underneath each family of designation, most will define particular requirements for dimensional tolerances, mechanical properties, material and surface finish criteria, and beyond.
• NSN-Based Identification: Most aerospace fasteners are assigned National Stock Numbers (NSNs) under the Federal Supply Classification system, which gives procurement teams a straightforward way to identify exact item records and verify them across government and commercial supply databases. For the benefit of your search, Federal Supply Class (FSC) 5305 covers screws, FSC 5306 covers bolts, and FSC 5320 covers rivets, among others.
• Material Traceability and Documentation: Every aerospace fastener procured for a regulated assembly should come with documentation that confirms compliance with any applicable specifications and offers traceability back to the original production facility. Oftentimes, this will come in the form of a certificate of conformance (CoC), supporting material records, and other documentation.

Where to Source Aerospace Fasteners with Confidence

As we have shown in this blog, aerospace fasteners form an important category of hardware for operations, where responsible procurement depends on buyers taking care in conducting searches and reviewing documentation to align offerings with internal needs. For those seeking a dependable source to address such requirements and more, Parts Distribution Services is an ASAP Semiconductor purchasing platform with a broad inventory of aerospace and aircraft fasteners that are traceable to leading manufacturers worldwide. ASAP Semiconductor maintains AS9120B, ISO 9001:2015, and FAA AC 00-56B accreditation across operations, with fulfillment standards aligned to the demands of regulated aerospace and defense programs. Thus, customers can explore our curated catalogs with peace of mind, where we make it easy to find items with everything organized by part number, manufacturer, NSN, and other common specifications. Simply submit a Request for Quote (RFQ) form through our website to get started with tailored pricing options, or contact our team directly by phone or email with any inquiries.