Applicability

This regulation introduces the rules that govern how flights are authorized to depart under different types of Part 121 operations.

For domestic and flag operations, airlines must follow "dispatching" rules, which involve a formal dispatch system where a certificated aircraft dispatcher shares responsibility with the pilot-in-command for flight planning, monitoring, and operational control. The dispatcher and pilot work together to release the flight.

For supplemental operations (typically charter flights), airlines follow "flight release" rules instead. These are less stringent—the pilot-in-command has primary authority to release the flight, though the airline's operational control system still provides support.

This distinction matters because it determines who has authority over flight operations, what qualifications are required, and what procedures must be followed before a flight departs. The subsequent regulations in this subpart detail the specific requirements for each operation type.

*This is a plain-English summary for study only. The official 14 CFR text on this page is controlling — always read the current regulation and consult a CFI.*