A visual observer (as they are known by FAA regulations) must adhere to the same guidelines as the Pilot in Command (PIC).
From §107.27:
- 8 hours from “bottle to throttle” (no drinking of alcohol within the last 8 hours),
- do not fly while under the influence of alcohol, including a hangover,
- do not fly while using any drug that may adversely affect safety,
- alcohol concentration below 0.04 in a blood or breath specimen.
From VLOS (§107.27) and VO (§107.33)
The aircraft must always be within visual line-of-sight (VLOS) of:
- The remote-PIC and the person operating the drone, or
- A visual observer (VO)
- VLOS means the aircraft is close enough to be seen without any aid such as binoculars (Contact lenses or glasses are excluded) .
Visual Observers should always be in communication with the PIC….if they are not standing side-by-side, then use of radios would be necessary. Some of the key responsibilities of the Visual Observer:
- Maintain VOLS with the aircraft
- Ensure that no other aircraft or no other people on the ground enter your area of operation
- Continuous communication with PIC on position, altitude, attitude, and movement of the sUAS
Is it hovering? Is it actually moving left vs. right? Is it shifting direction with the wind? Is it getting too close to a hazard/obstacle?
- Has another aircraft been spotted in the vicinity? If so, should the sUAS be grounded?
- If the aircraft is tasked to “return to home” (usually when something goes awry) ensuring communication to get the aircraft back safely
Bottom line, you’re right, it is applying a lot of common sense in ensuring the safe flight of your sUAS operation. The visual observer’s role is to “See and Avoid” and maintain a lookout for other potential hazards that may affect the safety of flight.