Article Approval

FAR 21.8 Article Approval

FAR 21.8 explains the four ways an aircraft article can be approved by the FAA: PMA, TSO, type certification, or other FAA-approved method.

In Plain English

FAR 21.8 lists the ways an article (a part, component, material, or appliance used on an aircraft) can be approved by the FAA when approval is required under Part 21. This matters because installing an unapproved part can make an aircraft unairworthy, grounding it until the issue is resolved.

Under this section, an article can be approved in any of the following ways:

  • (a) Under a PMA — a Parts Manufacturer Approval, which authorizes a manufacturer to produce replacement or modification parts.
  • (b) Under a TSO — a Technical Standard Order, which sets minimum performance standards for specified articles (think transponders, ELTs, seat belts).
  • (c) In conjunction with type certification — the article is approved as part of the original product's type certificate (TC) or supplemental type certificate (STC).
  • (d) In any other manner approved by the FAA — a catch-all giving the FAA flexibility to approve articles through other accepted means.

As a pilot, you don't issue these approvals, but you should recognize the terms when reviewing maintenance logbooks and 8130-3 forms during a preflight or annual review.

Regulation Text
14 CFR § 21.8
§ 21.8 Approval of articles. If an article is required to be approved under this chapter, it may be approved— (a) Under a PMA; (b) Under a TSO; (c) In conjunction with type certification procedures for a product; or (d) In any other manner approved by the FAA. [Doc. No. FAA-2006-5877, Amdt. 21-92, 74 FR 53385, Oct. 16, 2009]
Oral Exam Questions a DPE Might Ask
Q1What are the ways an aircraft article can be approved by the FAA?
Per FAR 21.8, an article may be approved under a PMA, under a TSO, in conjunction with type certification procedures for a product, or in any other manner approved by the FAA.
Q2If you see a part installed under a TSO, is it FAA approved?
Yes. FAR 21.8(b) specifically lists approval under a Technical Standard Order (TSO) as one of the accepted methods of article approval.
Q3Can the FAA approve an article using a method not specifically listed in the regulation?
Yes. FAR 21.8(d) is a catch-all provision that allows approval 'in any other manner approved by the FAA,' giving the agency flexibility beyond PMA, TSO, and type certification.
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FAR 21.8 — How Aircraft Articles Get FAA Approval