Regulations, Privileges, and Limitations
The Rule and the Certificate
Part 107 governs civil small unmanned aircraft (sUA) operations. The remote pilot certificate in a small unmanned aircraft system (sUAS) rating is what authorizes you to act as remote pilot in command (PIC). Know the recurring numbers: the sUA must weigh less than 55 lb at takeoff including everything attached or onboard; maximum groundspeed is 87 knots (100 mph); maximum altitude above ground level is 400 ft unless within a 400-ft radius of a structure, in which case you may fly no higher than 400 ft above the structure's uppermost limit; minimum visibility from the control station is 3 statute miles; minimum distance from clouds is 500 ft below and 2,000 ft horizontally.
Operating Rules Candidates Miss
You must be able to see the aircraft unaided (corrective lenses are fine, but not binoculars or a spotting scope). Visual observers may be used but do not replace your see-and-avoid responsibility. Operations over people, at night, and over moving vehicles each have specific conditions - night operations require anti-collision lighting visible for 3 statute miles and, unless you hold the required training, a waiver. Operations in Class B, C, D, and surface Class E require prior ATC authorization (LAANC or DroneZone); Class G needs none. Yield right-of-way to all manned aircraft, never carry hazardous material for compensation, and do not operate from a moving vehicle unless in a sparsely populated area.
Traps
Questions love to swap "statute miles" for "nautical miles," ask whether a waiver is needed for something already permitted, and test whether a visual observer's presence relaxes the cloud-clearance rule (it does not).
Rule of Thumb
"55–87–400–3": less than 55 lb, 87 knots, 400 ft AGL, 3 statute miles visibility.