TSO Holder Responsibilities

FAR 21.616 — TSO Holder Responsibilities

FAR 21.616 sets the duties of TSO authorization holders: quality system, conformity, marking, design data access, and FAA notifications. Study guide for pilots.

In Plain English

FAR 21.616 spells out what a holder of a Technical Standard Order (TSO) authorization must do to keep that authorization in good standing. A TSO authorization is the FAA's approval to produce an article (like an avionics box, seatbelt, or life vest) that meets a specific minimum performance standard. While this rule is aimed at manufacturers, pilots should understand it because it explains why TSO'd parts on your airplane are traceable and trustworthy.

Each TSO authorization holder must:

Update the organizational document required by §21.605 and send changes to the FAA.
Maintain a quality system that follows the approved TSO data and procedures.
Ensure every article conforms to its approved design, is safe to operate, and meets the applicable TSO.
Mark the article per Part 45, including any critical parts.
Identify sub-assemblies, components, or replacement parts leaving the facility with the manufacturer's part number and name/trademark.
Have access to all design data needed to verify conformity and airworthiness, and send it to the FAA when production ends.
Retain the TSO authorization and present it to the FAA on request.
Disclose any delegation of authority to suppliers to the FAA.

This is what makes a TSO tag on a part meaningful when you install or inspect equipment.

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Regulation Text

14 CFR § 21.616

§ 21.616 Responsibility of holder. Each holder of a TSO authorization must— (a) Amend the document required by § 21.605 as necessary to reflect changes in the organization and provide these amendments to the FAA. (b) Maintain a quality system in compliance with the data and procedures approved for the TSO authorization; (c) Ensure that each manufactured article conforms to its approved design, is in a condition for safe operation, and meets the applicable TSO; (d) Mark the TSO article for which an approval has been issued. Marking must be in accordance with part 45 of this chapter, including any critical parts; (e) Identify any portion of the TSO article (e.g., sub-assemblies, component parts, or replacement articles) that leave the manufacturer's facility as FAA approved with the manufacturer's part number and name, trademark, symbol, or other FAA approved manufacturer's identification; (f) Have access to design data necessary to determine conformity and airworthiness for each article produced under the TSO authorization. The manufacturer must retain this data until it no longer manufactures the article. At that time, copies of the data must be sent to the FAA; (g) Retain its TSO authorization and make it available to the FAA upon request; and (h) Make available to the FAA information regarding all delegation of authority to suppliers.

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Oral Exam Questions a DPE Might Ask

Q1What does a TSO authorization holder have to do to make sure each article they produce is acceptable?

Per FAR 21.616(c), the holder must ensure each manufactured article conforms to its approved design, is in a condition for safe operation, and meets the applicable TSO.

Q2How must a TSO article be marked, and where is that requirement found?

FAR 21.616(d) requires the TSO article to be marked in accordance with Part 45 of the regulations, including any critical parts.

Q3What must a TSO holder do with design data when they stop making the article?

Under FAR 21.616(f), the manufacturer must retain the design data while producing the article and, when production ends, send copies of that data to the FAA.

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