TSO Inspections and Tests

FAR 21.610 — TSO Inspections and Tests

FAR 21.610 requires TSO authorization applicants and holders to allow FAA inspections of quality systems, facilities, data, articles, and supplier tests.

In Plain English

FAR 21.610 is a short but important rule that applies to anyone applying for or holding a TSO (Technical Standard Order) authorization. A TSO is the FAA's minimum performance standard for certain articles (like avionics, life vests, or seat belts) used on civil aircraft.

Under this section, the applicant or holder must allow the FAA to:

Inspect the quality system used to produce the article
Inspect facilities where the article is manufactured
Inspect technical data supporting the design
Inspect any manufactured articles themselves
Witness any tests the FAA deems necessary, including those conducted at a supplier's facility

The purpose is to give the FAA the access it needs to verify that the article — and the system that produces it — actually complies with the requirements of Subchapter C (Aircraft). Operationally, this matters because TSO articles end up installed in aircraft you fly. Without FAA oversight authority, there would be no way to confirm that those parts truly meet the published performance standard.

Regulation Text

14 CFR § 21.610

§ 21.610 Inspections and tests. Each applicant for or holder of a TSO authorization must allow the FAA to inspect its quality system, facilities, technical data, and any manufactured articles and witness any tests, including any inspections or tests at a supplier facility, necessary to determine compliance with this subchapter.

Oral Exam Questions a DPE Might Ask

Q1What is a TSO authorization holder required to allow the FAA to inspect?

Per FAR 21.610, the holder must allow the FAA to inspect its quality system, facilities, technical data, and any manufactured articles, and to witness any tests necessary to determine compliance.

Q2Does FAA inspection authority under FAR 21.610 extend to supplier facilities?

Yes. FAR 21.610 specifically states the FAA may conduct inspections or witness tests at a supplier's facility, not just the TSO holder's own facility.

Q3Who does FAR 21.610 apply to — applicants, holders, or both?

FAR 21.610 applies to both applicants for and holders of a TSO authorization; both must allow FAA inspections and tests to verify compliance with the subchapter.

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Related Sections in Part 21

§ 21.1

Certification Procedures

§ 21.101

Type Certificate Changes