Are instructions in the Federal Regulations mandatory or optional?

• A. Optional
• B. Mandatory
• C. Neither mandatory nor optional
• D. Discretionary by FAA

Answer: (B)

Instructions in the Federal Regulations are mandatory. The CFRs establish binding requirements that tell you exactly what you must do, what you may not do, and under what conditions you must act. When a regulation uses words like shall or must, it indicates a legally enforceable obligation, and noncompliance can lead to penalties or other enforcement actions by the FAA. Guidance documents outside the regulations, such as advisory circulars, are intended to help interpretation and implementation but are not binding unless the regulation itself makes them mandatory. So the rules you find in the Federal Regulations are required to follow.