General

This regulation serves as an introduction to Subpart B of Part 135, which covers flight operations for commuter and on-demand air carriers. It clarifies that operators conducting flights under Part 135 must comply with both the general operating rules in Part 91 (which apply to all aircraft operations) and the additional, more stringent requirements specific to Part 135.

In practical terms, this means Part 135 operators don't get to replace Part 91 rules—they must follow both sets of regulations. For example, a Part 135 pilot must observe Part 91's basic right-of-way rules while also meeting Part 135's stricter requirements for things like crew rest, maintenance programs, and operational control. When Part 135 has a specific rule on a topic, it typically supersedes the corresponding Part 91 rule, but only where explicitly stated. This layered regulatory structure ensures commercial operators maintain higher safety standards than general aviation while preserving foundational aviation rules that apply to everyone.

*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.*