What are the limits to Visual Line of Sight (VLOS)?

• A. The observer can see the system from any distance with any device
• B. The observer must remain within three miles of the aircraft
• C. The furthest point at which an observer can see the system's location, as well as determine the system's attitude, altitude, and direction of flight with an unaided eye
• D. The remote pilot must maintain direct line of sight at all times

Answer: (C)

Visual Line of Sight means you must be able to see the drone with your unaided eye and be able to judge its position and its orientation as it flies. The limit is defined by how far you can see the aircraft and still determine where it is, what its attitude (which way it’s pointing), its altitude, and the direction it’s moving, all without using magnifying devices. That distance isn’t a fixed number like a certain miles; it varies with lighting, weather, background, the drone’s size, and your own vision. If you can’t reliably determine those factors with the unaided eye, you’re outside VLOS and would need to stay within sight or rely on another method or observer.