Supplemental Type Certificate
STCSection 13: Jurisdiction Mapping Sets
Definition
A design approval issued for a major modification to the type design of an existing type-certificated product (aircraft, engine, or propeller). The STC approves the design change and the associated installation instructions, maintenance data, and, where applicable, flight manual supplements. The STC holder has the authority to produce the modification kit and the obligation to provide Instructions for Continued Airworthiness.
Where This Shows Up
The STC process is used when a modification is too significant to be classified as a minor change (which could be approved by the TC holder or a DOA/DER/ODA). STCs are commonly used for avionics upgrades, engine changes, structural modifications, and performance enhancements to existing aircraft types. The STC certification basis includes the applicable certification specifications in effect at the time of the original type certificate (or a later amendment agreed with the authority), plus any additional conditions required by the authority for the specific modification. STC approval across multiple jurisdictions typically requires either validation (acceptance by the importing authority) or a parallel certification process.
Primary Sources
Across Jurisdictions
14 CFR Part 21 Subpart E
Applied for under 14 CFR Part 21 Subpart E. The applicant works with the responsible ACO (or through an ODA) to establish the certification basis, develop compliance plans, and submit compliance data. The FAA issues the STC upon finding compliance. The STC holder may authorize others to produce the modification through licensing agreements.
EASA Part 21 Subpart E
Applied for under EASA Part 21 Subpart E. For major changes (which require STCs), the applicant must work directly with EASA or through a DOA with appropriate privileges. EASA classifies changes as major or minor using defined criteria. The STC certification basis is established through the certification programme, which may include Certification Review Items (CRIs).
EASA's classification of major vs. minor changes follows defined criteria in Part 21 21.A.91. The DOA may have privileges to classify and approve minor changes without EASA involvement.
CAR Part V, AWM Chapter 521
TCCA STC procedures follow a similar process to FAA and EASA. TCCA frequently validates FAA or EASA STCs under bilateral agreements, which can significantly streamline the approval process for modifications already approved in those jurisdictions.
Related Terms
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