Major Change vs Minor Change
Section 03: Certification & Approval Types
Definition
The classification of a change to a type design as either major or minor, which determines the approval process and regulatory path. A major change is one that has an appreciable effect on the weight and balance, structural strength, performance, powerplant operation, flight characteristics, or other qualities affecting the airworthiness of the product, or that is not done according to accepted practices or cannot be done by elementary operations. A minor change is one that does not meet the criteria for major. Major changes require more extensive compliance demonstration and authority involvement.
Where This Shows Up
The classification of a change as major or minor is a critical decision in the certification process because it dictates the approval pathway: major changes require STC or TC amendment processes with full compliance demonstration, while minor changes may be approved through simpler procedures (e.g., by a DER, ODA, or DOA without direct authority involvement).
Primary Sources
Across Jurisdictions
14 CFR § 21.93
The FAA classifies changes as major or minor. Major changes are approved under 21.95 (by the TC holder) or 21.115 (STC). Minor changes are approved under 21.95 through simpler procedures.
Part 21, 21.A.91
EASA classifies changes as 'significant' (major) or 'minor.' A DOA holder has the privilege to classify changes and to approve minor changes directly.
EASA uses the term 'significant change' rather than 'major change' in Part 21. The classification criteria are functionally similar to the FAA's.
Related Terms
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