Amended Type Certificate
ATCSection 03: Certification & Approval Types
Definition
A modification to an existing Type Certificate that reflects a major change in the type design. An Amended TC is sought when the TC holder (or a person with proper licensing agreements) proposes changes that are significant enough to be classified as a major change but do not warrant a new, separate TC. The certification basis for an ATC typically includes the original TC certification basis plus any additional requirements triggered by the nature and extent of the change, as determined by the authority.
Where This Shows Up
The distinction between a major change processed as an ATC and a change that requires a new TC application depends on the scope and nature of the change. Derivative aircraft models (e.g., a stretched fuselage variant) are typically certificated through an ATC rather than a new TC. The classification of changes as major or minor is governed by 14 CFR 21.93 (FAA) or Part 21.A.91 (EASA).
Primary Sources
FAA procedures for processing changes to type design, including amended TCs.
Across Jurisdictions
14 CFR § 21.19, § 21.93, § 21.95, § 21.101
The FAA processes major changes to a TC as Amended Type Certificates. The certification basis is determined per 21.101.
Part 21, 21.A.91 through 21.A.109
EASA classifies changes as major or minor per 21.A.91. Major changes may be approved through a DOA privilege or require direct EASA approval.
EASA does not use the specific term 'Amended Type Certificate' in the same formal way as the FAA. EASA instead processes major changes to a TC under 21.A.95 and 21.A.97.
Related Terms
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