Glossary

The National Aerospace Standards (NAS), a type of industry-developed aerospace specification used to define the required dimensions, materials, performance, testing, interchangeability, and quality expectations for aerospace parts, processes, or practices. The Aerospace Industries Association, or AIA, maintains the NAS library and states that these are voluntary standards developed by industry to support the manufacturing and operation of aerospace products. AIA also notes that the NAS library contains more than 1,100 active standards, and that these standards have been developed since 1941.

In practical hardware use, “NAS” is often seen in aerospace fastener part numbers and related component specifications. When a bolt, nut, pin, or other part is described as a NAS item, it generally means it is built to an aerospace standard that is more tightly controlled than ordinary commercial hardware, often with requirements for closer tolerances, higher strength, special geometry, and more rigorous acceptance criteria. AIA’s National Aerospace Standards Committee says its NAS part standards are recognized for meeting the high-strength, close-tolerance, and rigorous acceptance-testing requirements of the aerospace industry. The FAA also groups NAS hardware alongside other accepted aviation standards such as AN and MS when discussing aircraft fasteners and approved hardware.

The term does not refer to one single document. Instead, it refers to a large family of standards covering many aerospace subjects. Some NAS standards define specific parts, such as certain bolts or fittings, while others address broader technical requirements, inspection qualifications, or system practices. For example, AIA recently described NAS410 as a core aerospace standard for qualification and certification of nondestructive testing personnel, which shows that NAS standards are not limited only to fasteners.