Applicability

This regulation sets the scope for flight and duty time rules that apply to Part 121 supplemental all-cargo operations. By default, these operations follow the requirements in this subpart (Subpart R).

However, operators have two alternative options:

Smaller aircraft exception: If you fly aircraft with 30 or fewer passenger seats and a payload capacity of 7,500 pounds or less, you may instead follow the Part 135 rules (§§135.261-135.273), which are generally designed for smaller operations.

Part 117 option: Any supplemental cargo operator may choose to follow Part 117's flight and duty time rules instead, whether flying for government contracts or commercial customers. However, you must apply this choice consistently—you can treat government and commercial cargo operations differently, but once you choose Part 117 for either category, you cannot pick and choose which flights follow which rules within that category.

*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.*