Rules
Part 107 visual line of sight and visual observers explained
Under 14 CFR 107.31 the remote pilot in command and the person at the controls, or a visual observer, must see the drone with unaided vision (corrective lenses allowed) for the whole flight. A visual observer is optional, but if you use one, 107.33 requires constant communication and a clear view of the aircraft.
What exactly does 107.31 require?
The rule says the remote pilot in command, the person manipulating the flight controls, and, if used, the visual observer must be able to see the unmanned aircraft throughout the entire flight, with vision that is unaided other than by corrective lenses. The purpose is spelled out: to know the aircraft's location, know its attitude, altitude and direction of flight, observe the airspace for other air traffic or hazards, and determine that the aircraft does not endanger the life or property of another. Paragraph (b) then says this can be done by the remote pilot in command and the person at the controls, or by a visual observer.
Two things stand out. There is no distance in miles or feet: the limit is what you can see well enough to judge attitude and direction. And the phrase is "throughout the entire flight," so briefly losing sight behind a tree line or against a bright sky is a lapse, not a gray area.
Sources (checked 2026-11-14): 14 CFR 107.31 (eCFR).
What counts as unaided vision, and what about FPV?
Only glasses or contact lenses are allowed. Binoculars, a spotting scope, a camera feed on a screen, and FPV goggles all fall outside "unaided." So you may use FPV goggles for the shot, but they do not satisfy 107.31 by themselves. Someone who is looking directly at the aircraft with their own eyes must also be doing the job: either the remote pilot in command, or a visual observer who is looking at the drone and talking to the pilot.
Worked example
Goggles on, observer standing next to you
Say you fly a racing quad through a field in goggles. You are the pilot at the controls and the remote pilot in command, and a friend stands beside you and keeps the quad in sight at all times, talking to you. If the friend is acting as your designated visual observer under 107.33, the flight can satisfy 107.31, because the visual observer shares the duty. If the friend is just watching with no designated role or two-way communication, you have no observer. Your goggle view does not count, and the flight is not within visual line of sight.
Sources (checked 2026-11-14): 14 CFR 107.31 (eCFR); 14 CFR 107.33 (eCFR).
What are the visual observer requirements in 107.33?
If you use a visual observer, three things must be true. First (a), the remote pilot in command, the person at the controls, and the visual observer maintain effective communication with each other at all times. Second (b), the remote pilot in command ensures the visual observer can see the aircraft as 107.31 describes. Third (c), all three coordinate to scan the airspace for collision hazards and to keep track of the aircraft's position through direct visual observation. The definition in 107.3 makes the role concrete: a visual observer is a person the remote pilot in command designates to assist in seeing and avoiding other air traffic or objects, in the air or on the ground.
Notice that nothing here requires an observer. Plenty of flights run with the remote pilot in command watching the aircraft alone. The observer is a tool that lets the pilot look at a screen or work other tasks while still meeting 107.31.
Sources (checked 2026-11-14): 14 CFR 107.33 (eCFR); 14 CFR 107.3 (eCFR).
Can I chain observers to extend the distance?
No, the rules give you no way to do it without a waiver. Section 107.31 requires someone with a direct view of the aircraft among the remote pilot in command, the person at the controls, or the visual observer, and 107.33(b) says the pilot ensures the visual observer can see the aircraft. A second observer who can see only the first observer, and relays "he has it" by radio, does not have the aircraft in sight. The aircraft's position is then known only second-hand, which is what the rule is written to prevent.
If your work needs flight beyond visual line of sight, or a different observer arrangement, the FAA's waiver list in 107.205 includes both 107.31 and 107.33. The waiver cannot authorize carrying someone else's property by aircraft for compensation or hire. See waivers and authorizations.
Sources (checked 2026-11-14): 14 CFR 107.205 (eCFR); FAA: Part 107 Waivers.
Can one person fly more than one drone?
Section 107.35 says a person may not manipulate flight controls or act as remote pilot in command or visual observer in the operation of more than one unmanned aircraft at the same time. Two controllers in two hands, or one pilot flying a pair, is covered. The rule is also on the waiver list (107.205), but a waiver would be required.
The rule applies to the roles individually. One person cannot be the visual observer for the pilot in command's drone and also fly a second drone, because acting as an observer for one aircraft while flying another puts that person into two operations at once.
Sources (checked 2026-11-14): 14 CFR 107.35 (eCFR); 14 CFR 107.205 (eCFR).
Does the observer share responsibility?
The remote pilot in command remains directly responsible for the flight and has final authority (107.19). The observer helps, and a person who acts as visual observer is also covered by the physical and mental condition rule in 107.17 and by the alcohol and drug rule in 107.27. An observer who is impaired or too tired to track the aircraft breaks those rules even though they never touch the controls. Under 107.49(b), before the flight the remote pilot in command makes sure all persons directly participating are informed about operating conditions, emergency and contingency procedures, roles and responsibilities, and potential hazards. Cover how the observer will call out traffic, and agree on words for "lost sight," "traffic" and "abort."
Sources (checked 2026-11-14): 14 CFR 107.19 (eCFR); 14 CFR 107.17 (eCFR); 14 CFR 107.49 (eCFR).
How do I work through VLOS scenarios on the test?
Check the same three questions each time: who is looking at the aircraft with unaided eyes, can they stay in contact with the pilot, and can they identify the aircraft's attitude and direction? A change in any one flips the answer.
| Scenario | Meets VLOS? | Why |
|---|---|---|
| Pilot watches a small drone at 300 ft AGL on a clear day, 200 yards away | Yes, if the pilot can judge attitude and direction | 107.31(a) is about what you can see, not a fixed distance |
| Pilot flies on a monitor and never looks at the aircraft, no observer | No | A screen is an aid; nobody has direct sight |
| Pilot in FPV goggles, designated observer talking by voice and watching the aircraft | Yes | 107.31(b) and 107.33: observer shares the duty |
| Pilot uses binoculars to see a drone far out | No | Binoculars are not corrective lenses |
| Observer sees the aircraft but cannot talk to the pilot (dead radio, loud site) | No | 107.33(a) requires effective communication at all times |
| Drone slips behind a ridge for 30 seconds | No for that period | 107.31 applies throughout the entire flight |
Worked example
Observer loses sight
Say your observer reports "I lost it behind the building" while you are watching the camera view. The flight is no longer within visual line of sight if you are also not seeing it. Under 107.19 you are responsible for restoring it or ending the flight: climb or move to regain direct sight, command return, and brief the observer so they speak up at once next time.
Sources (checked 2026-11-14): 14 CFR 107.31 (eCFR); 14 CFR 107.33 (eCFR); 14 CFR 107.19 (eCFR).
Which test traps come up around this rule?
- "Binoculars are fine because they help the observer." Not if they replace unaided vision. The rule allows only corrective lenses.
- "A visual observer is required for every flight." It is not; 107.33 begins "if a visual observer is used."
- "A video feed satisfies VLOS." No. First-person view is an aid.
- "I can pilot two aircraft if both are close." No, 107.35 does not make an exception for distance.
- "I can add observers to extend range." Not without a waiver of 107.31 or 107.33.
Related drills are in Part 107 operating rules and aeronautical decision-making.
How do light, distance and background affect line of sight?
107.31 does not name a range, so the working limit is the point where you can no longer tell which way the aircraft is facing or tilting. That point moves with conditions. A white drone against a bright overcast sky disappears sooner than a dark one against a green hillside. Haze, glare from low sun and small airframes all shorten the usable distance, and night flight adds lighting requirements covered in night operations.
Worked example
A drone that fades at 500 ft
Say you fly a small gray quad on a hazy afternoon. At about 500 feet out you can still see a dot but cannot tell whether it is turning toward you or away. You are no longer meeting the purpose of 107.31 (to know attitude and direction). Bring it back in until you can read its orientation, or, if the shot needs more range, put an observer closer to the action who can see it and talk to you.
Sources (checked 2026-11-14): 14 CFR 107.31 (eCFR); 14 CFR 107.33 (eCFR).
Free practice questions on this topic
1 original questions from the Sectional Cue bank. Try each one, then open the answer.
Crew briefing
1. Before flight, which people must the remote pilot in command make sure are informed about emergency procedures, roles and potential hazards?
- Every person within 500 feet of the takeoff point
- All persons directly participating in the operation
- The nearest air traffic control facility, by phone before launch
Show answer and explanation
B. All persons directly participating in the operation
Section 107.49(b) requires the remote pilot in command to ensure all persons directly participating are informed about operating conditions, emergency and contingency procedures, roles and responsibilities, and potential hazards. Nothing requires briefing everyone within 500 feet. Air traffic control is not a crew member to be briefed.
Source: 14 CFR 107.49(b)
Related guides
- Part 107 operating rules: altitude, speed, visibility and clouds
- Part 107 waivers and airspace authorizations
- Aeronautical decision-making, CRM and human factors
- Part 107 night operations: lights, twilight and training
- The Part 107 400-foot rule near structures, and the 87-knot limit
- All Part 107 guides
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Sources
- 14 CFR 107.31 (eCFR), checked 2026-11-14
- 14 CFR 107.33 (eCFR), checked 2026-11-14
- 14 CFR 107.35 (eCFR), checked 2026-11-14
- 14 CFR 107.3 (eCFR), checked 2026-11-14
- 14 CFR 107.205 (eCFR), checked 2026-11-14
- FAA: Part 107 Waivers, checked 2026-11-14
How this page was made: written by Certloom Learning from the sources above, with the rules checked against the current regulation text. Practice items are original questions from the app's reviewed bank. Spot an error? certloomlearning@gmail.com.