Category 1 is the simplest path over people, and § 107.110 defines it with two facts about the aircraft. First, it must weigh 0.55 pounds or less — and not just at takeoff. The limit holds throughout the duration of each operation and counts everything on board or otherwise attached to the aircraft, so a camera, a battery upgrade, or a payload that pushes the total past 0.55 pounds drops you out of Category 1 mid-flight. Second, the aircraft must not contain any exposed rotating parts that would lacerate human skin upon impact — in practice, propellers shrouded or guarded so a strike would not open a cut.

What makes Category 1 the easy path is what it does not require. Unlike Categories 2 and 3, it asks for no manufacturer's declaration of compliance and no injury-threshold testing — an aircraft either meets the weight and the exposed-parts conditions or it does not, and the remote pilot can confirm both by knowing the aircraft. That is the trade the rule makes: keep the machine light enough and free of cutting parts, and the FAA treats the risk to a person underneath as low enough to permit the overflight without paperwork.

There is one important addition even Category 1 does not escape. Under § 107.110(b), no remote pilot may operate in sustained flight over an open-air assembly of human beings — a crowd — unless the operation also meets the Remote ID requirements of § 89.110 or § 89.115(a). So a light, guarded Category 1 aircraft clears the routine over-people bar, but the moment the people below become an open-air assembly, Remote ID becomes a condition of the flight. What Remote ID is and how those two paths work is the subject of Chapter 6; here the point is simply that crowds raise the bar, even for the lightest category.