New Type Certificate

FAR 21.19 — New Type Certificate

FAR 21.19 explains when a proposed change to an aircraft's design, power, thrust, or weight is extensive enough to require applying for a new type certificate.

In Plain English

FAR 21.19 sets the threshold for when a change to an existing aircraft, engine, or propeller is too big to handle as an amendment to the original type certificate — and instead requires applying for an entirely new type certificate.

The rule says that anyone proposing to change a product must apply for a new type certificate if the FAA determines the proposed change is so extensive that a substantially complete investigation of compliance with the applicable regulations is needed. The FAA looks at changes in:

Design
Power
Thrust
Weight

Why it matters operationally: type certification is the foundation of an aircraft's airworthiness. Smaller modifications can often be approved through an amended type certificate or a Supplemental Type Certificate (STC), but truly major redesigns essentially produce a new product that must be re-evaluated from the ground up. This protects safety by ensuring sweeping changes get a full compliance review rather than a piecemeal approval.

Regulation Text

14 CFR § 21.19

§ 21.19 Changes requiring a new type certificate. Each person who proposes to change a product must apply for a new type certificate if the FAA finds that the proposed change in design, power, thrust, or weight is so extensive that a substantially complete investigation of compliance with the applicable regulations is required. [Doc. No. 28903, 65 FR 36265, June 7, 2000]

Oral Exam Questions a DPE Might Ask

Q1Under what circumstances must a manufacturer apply for a new type certificate instead of amending an existing one?

Per FAR 21.19, a new type certificate is required when the FAA finds that a proposed change in design, power, thrust, or weight is so extensive that a substantially complete investigation of compliance with applicable regulations is required.

Q2What four categories of changes does FAR 21.19 specifically identify as potentially triggering the need for a new type certificate?

FAR 21.19 identifies changes in design, power, thrust, or weight as the categories the FAA evaluates when deciding whether a new type certificate application is required.

Q3Who decides whether a proposed change is extensive enough to require a new type certificate under FAR 21.19?

Under FAR 21.19, the FAA makes that determination, based on whether a substantially complete investigation of compliance with the applicable regulations would be required.

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Related Sections in Part 21

§ 21.1

Certification Procedures

§ 21.101

Type Certificate Changes