Guidance Documents — AC, AMC/GM, SI
Section 13: Jurisdiction Mapping Sets
Definition
Non-mandatory guidance material published by certification authorities that provides acceptable means of compliance with the regulatory requirements, explanatory material, and recommended practices. While not legally binding, guidance documents describe methods that the authority has pre-accepted as demonstrating compliance with the applicable rules, and deviation from them typically requires coordination with the authority to establish an equivalent alternative means.
Where This Shows Up
The hierarchy of aviation regulations follows a layered structure: regulations (rules) define mandatory requirements, and guidance documents describe acceptable methods for meeting those requirements. Using the accepted guidance provides a predictable and efficient certification path; proposing alternative methods increases certification risk and timeline because the applicant must demonstrate equivalence to the authority's satisfaction. Understanding the guidance document system in each jurisdiction is essential for planning certification activities and anticipating the authority's expectations.
Primary Sources
EASA publishes AMC and GM as annexes to its implementing rules, updated through rulemaking decisions.
Across Jurisdictions
FAA Order 1320.46
ACs provide guidance and information for compliance with FAA regulations. They are not mandatory but describe an acceptable means of compliance. When an AC is referenced in a regulation or TSO, the referenced document effectively becomes the accepted standard. Key certification ACs include AC 20-115D (DO-178C), AC 20-152 (DO-254), AC 21-16G (DO-160), and AC 25.1309-1A (system safety).
Regulation (EU) 2018/1139 Article 76
AMCs describe means to establish compliance with the implementing rules (regulations). If an applicant follows an AMC, the authority presumes compliance with the corresponding rule. GM provides explanatory and interpretive material but does not describe specific compliance means. AMC and GM are published as part of EASA's rulemaking decisions and are organized by the rule section they support (e.g., AMC 20-115D for software, AMC 20-152 for hardware).
EASA's AMC system provides a more structured presumption of compliance than FAA ACs. An applicant who follows the AMC is presumed compliant; an applicant who proposes an alternative must demonstrate it provides an equivalent level of safety.
TCCA Policy Framework
TCCA publishes Staff Instructions (SIs) for internal guidance to TCCA staff, and Advisory Circulars (ACs) for external guidance to applicants and operators. TCCA ACs often mirror or adopt FAA ACs by reference. SIs provide the TCCA-specific implementation procedures and policy for certification activities.
TCCA Staff Instructions are internal documents that may not always be publicly available, unlike FAA ACs and EASA AMCs which are published. However, SIs that affect applicants are typically made available upon request.
Related Terms
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