What does VLOS mean?

VLOS stands for visual line of sight .

This is a term that comes up again and again, especially in the field of drones, as flying beyond visual line of sight (BVLOS) is often limited and can be affected by bad weather (fog, thunderstorms) or small drones that are difficult to recognise even at close range. There is also a further designation, flight with extended visual contact (EVLOS) . This involves the use of an airspace observer who can maintain visual contact with the drone, even if the drone is no longer within sight of the remote pilot.