Which statement about Airworthiness Directives and maintenance advisories is accurate?

• A. ADs are optional guidelines; advisories are mandatory.
• B. ADs apply to all aircraft components regardless of safety.
• C. ADs are legally mandatory for safety-critical items; maintenance advisories are recommendations.
• D. ADs impact only ground operations.

Answer: (C)

Airworthiness Directives are enforceable requirements issued by the aviation authority to address safety-critical issues on aircraft or components. They specify what must be done—such as inspections, repairs, or modifications—and include timing for compliance. Because they relate directly to airworthiness and flight safety, compliance is mandatory and non-negotiable.

Maintenance advisories, by contrast, are guidance notes or recommendations from the manufacturer or authority. They help plan and perform maintenance to reduce risk but do not create a legal obligation on their own unless a regulation or an AD requires them to be followed.

So the accurate statement is that Airworthiness Directives are legally mandatory for safety-critical items, while maintenance advisories are recommendations. The other options don’t fit because ADs aren’t optional, they’re not issued for all components regardless of safety, and they can impact flight operations—not just ground operations.