Type Certificate Licensing

FAR 21.55 Type Certificate Licensing

FAR 21.55 explains the duties of type certificate holders who license their TC to manufacturers, including SMS compliance and written agreements.

In Plain English

FAR 21.55 sets the rules a type certificate (TC) holder must follow when they license another company to use that TC to build a new aircraft, aircraft engine, or propeller.

In plain terms, if you own the design approval (the TC) and let someone else manufacture products under it, you don't get to step away from quality and safety oversight. You remain responsible for two things:

  • Meeting the applicable requirements of Part 5 of this chapter — Part 5 is the FAA's Safety Management System (SMS) rule. The TC holder must have an SMS that addresses the licensed manufacturing activity.
  • Providing a written licensing agreement to the manufacturer that is acceptable to the FAA.

Why it matters operationally: this rule keeps accountability with the original design holder, even when production is handed off. It ensures airworthiness, configuration control, and safety risk management aren't lost in the handoff between the design organization and the licensed builder — protecting pilots and passengers who fly the resulting product.

Regulation Text
14 CFR § 21.55
§ 21.55 Responsibilities of type certificate holders who license the type certificate. A type certificate holder who allows a person to use the type certificate to manufacture a new aircraft, aircraft engine, or propeller must meet the applicable requirements of part 5 of this chapter and provide that person with a written licensing agreement acceptable to the FAA. [Docket No. FAA-2021-0419, Amdt. No. 21-108, 89 FR 33108, Apr. 26, 2024]
Oral Exam Questions a DPE Might Ask
Q1If a type certificate holder lets another company manufacture aircraft under their TC, what are their responsibilities?
Per FAR 21.55, the TC holder must meet the applicable requirements of Part 5 (Safety Management System) and provide the licensed manufacturer with a written licensing agreement that is acceptable to the FAA.
Q2Does FAR 21.55 apply only to aircraft, or to other products as well?
FAR 21.55 applies to type certificate holders licensing the TC to manufacture a new aircraft, aircraft engine, or propeller — all three product categories are covered.
Q3Is a verbal or informal arrangement enough to license a type certificate to another manufacturer?
No. FAR 21.55 specifically requires a written licensing agreement, and that agreement must be acceptable to the FAA — informal or verbal arrangements do not satisfy the rule.
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FAR 21.55 — Type Certificate Licensing Responsibilities