The foundation of drone safety in shared skies is deliberately low-tech: someone must be able to see the aircraft with unaided vision — ordinary glasses or contacts are fine — throughout the entire flight, well enough to know its position and direction and to scan the sky around it for other traffic. This requirement is called visual line of sight (VLOS). Binoculars and screens, including first-person-view devices, cannot satisfy this core requirement on their own, though FAA guidance notes that vision aids such as binoculars may be used momentarily to supplement situational awareness — for example, to confirm the aircraft isn't drifting toward a person or another aircraft — before returning to unaided observation. The remote pilot in command (the person who is directly responsible for, and the final authority as to, the operation of the small unmanned aircraft system) may personally fly the aircraft, or may direct a different person to manipulate the flight controls, so long as they retain the ability to immediately take direct control. Either way, visual line of sight must be maintained by the remote pilot in command together with whoever is manipulating the controls, or by a visual observer — an optional crew role the remote pilot in command may choose to use, designating and briefing that person as a crewmember for the flight — who keeps eyes on the aircraft while another crew member flies by camera view. The requirement exists because your eyes are the collision-avoidance system: a screen tells you where the camera points, not what is converging on your aircraft from behind.

Around airports, the sky is organized into classes, and the ones that matter most here are B, C, D, and E. These classes form a hierarchy: under the FAA's airspace rules, Class B airspace is more restrictive than Class C, Class C more restrictive than Class D, and Class D more restrictive than Class E — reflecting how much traffic concentrates in each zone and how tightly it's controlled. Classes B, C, D, and E are the controlled airspace classes you will deal with under Part 107, because air traffic control actively manages traffic within their boundaries; airspace outside those boundaries is uncontrolled. At most airports, Class E begins at a fixed altitude above the ground — 700 feet or 1,200 feet, depending on the area. The exception matters: at some airports, Class E instead extends all the way down to the surface, covering the ground and the airspace immediately around the airport rather than starting higher up — and because it's still Class E, that surface-level area carries the same authorization requirement as Class B, C, or D, even though you might be flying only a few dozen feet up. Inside Class B, C, or D airspace — or within that surface-level Class E area around an airport — you need prior authorization from air traffic control (ATC) — the service that directs and sequences the arrival and departure of crewed aircraft at and around airports — before you fly. The reason is plain: those rings are exactly where crewed aircraft concentrate at low altitude, climbing out and descending in.

Getting that authorization often moves quickly. The FAA lists a system called LAANC (Low Altitude Authorization and Notification Capability), part of its UAS Data Exchange, among its airspace resources; information on the current authorization process is available at faa.gov/uas. Keep the vocabulary straight: an authorization lets you enter controlled airspace while following all the normal rules; a waiver — a separate, slower instrument under § 107.200, explained in detail later in Chapter 2.6 — lets you deviate from a rule itself, such as flying beyond visual line of sight. Confusing the two is one of the most common mistakes in commercial drone work.