VLOS and Visual Observers Under Part 107
Visual line of sight sounds self-explanatory until the exam asks what counts as maintaining it, and what a visual observer can and can't do about it.
Visual line of sight is one of those Part 107 concepts everyone thinks they understand until a scenario question gets specific about what tool the pilot used to see the aircraft, or what a visual observer is actually allowed to do with that information.
What VLOS means, precisely
14 CFR §107.31 requires the remote pilot in command, the person manipulating the controls, and any visual observer to be able to see the unmanned aircraft throughout the entire flight with vision unaided by any device other than corrective lenses. Binoculars, a first-person-view headset, or a camera feed don't satisfy the requirement, no matter how good the picture is. The rule is about the human eye maintaining a direct line of sight, not about the pilot having situational awareness through some other means.
FPV goggles and camera feeds are genuinely useful tools, but they don't substitute for VLOS under the base rule. Operations that rely on them for the primary means of seeing the aircraft need a waiver, they aren't a workaround built into §107.31 itself.
What a visual observer changes, and what it doesn't
Adding a visual observer under 14 CFR §107.33 doesn't extend how far or how the pilot can fly; it adds a second set of eyes. The observer has to be able to see the aircraft with the same unaided-vision standard the pilot is held to, and has to be able to communicate with the pilot or the person manipulating the controls immediately enough to relay traffic, airspace, or hazard information in time for it to matter. A visual observer standing too far away to see the aircraft clearly, or with no working way to communicate in real time, isn't providing the function the rule requires just by being present on site.
A visual observer doesn't move where the aircraft is allowed to fly. They move how much the pilot has to see themselves.
The scenario the exam likes to build
A common trap: a pilot loses direct sight of the aircraft behind a building or tree line for a few seconds, but a visual observer positioned elsewhere maintains sight the whole time. Whether that's compliant depends on whether the pilot, the observer, and the person manipulating the controls (if different from the pilot) collectively maintain the VLOS and communication requirements as designed, not on any one person having eyes on the aircraft at every instant. The regulation is written around the roles working together, and exam scenarios are built to test whether you're tracking all three roles or just assuming the pilot alone has to see everything.
What still applies regardless
Neither VLOS nor a visual observer changes anything about airspace authorization, registration, or the operating limitations already in place. They answer one specific question, can the aircraft be adequately seen, not whether the flight is otherwise authorized to happen.
Full task breakdown and drills for this topic are in the handbook.
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