Service Bulletin
SBSection 12: Continued Airworthiness & Maintenance
Definition
A document issued by the type certificate holder (aircraft, engine, or equipment manufacturer) that provides instructions for inspection, modification, or repair of a product to address a design improvement, reliability enhancement, or safety concern. Service bulletins are generally not mandatory unless mandated by an Airworthiness Directive, although operators may choose to implement them voluntarily to improve safety, reliability, or performance.
Where This Shows Up
Service bulletins are the manufacturer's primary mechanism for communicating post-certification modifications and improvements to operators. They are classified by urgency: Alert SBs address safety concerns requiring urgent action (and are typically mandated by a subsequent AD), Mandatory SBs address conditions the manufacturer considers essential, and Recommended/Optional SBs address improvements. An SB includes the affected product identification, description of the modification, required parts and materials, accomplishment instructions, labor estimates, and effectivity (which serial numbers are affected). SBs are tracked by the operator's configuration management system.
Primary Sources
The industry standard for the format and content of aircraft technical publications, including the structure of service bulletins.
Related Terms
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