Visual Line of Sight

Visual Line of Sight

Visual line of sight, commonly called VLOS, is one of the core Part 107 operating requirements. During every flight, the operation must be conducted so the aircraft can be seen with vision unaided by any device other than corrective lenses. This is not merely about spotting the drone; it is about maintaining the awareness needed to operate safely.


What Visual Line of Sight Allows You To Do

The person performing the VLOS function must be able to see the aircraft well enough to do all of the following:

  • Know the aircraft’s location: Know where the drone is in relation to the control station, people, property, and planned flight path.
  • Determine attitude, altitude, and direction of flight: Be able to tell what the aircraft is doing and where it is heading.
  • Scan for other aircraft and hazards: Use VLOS to support collision avoidance and awareness of obstacles in the operating area.
  • Determine that the aircraft does not endanger others: The Remote PIC remains responsible for ensuring the operation does not endanger people, aircraft, or property.


Corrective Lenses, Binoculars, and FPV Goggles

Corrective lenses, such as eyeglasses or contact lenses, may be used to meet the VLOS requirement. Binoculars, telescopes, and first-person-view goggles may not be used as the primary method of keeping visual contact with the small UAS.

You may use binoculars briefly to inspect a distant obstacle or other traffic, but you may not rely on them instead of maintaining the required direct visual awareness of the drone.

Exam shortcut: Corrective lenses are permitted. Binoculars, telescopes, and FPV goggles do not satisfy VLOS.


Briefly Losing Sight of the Aircraft

A Remote PIC does not have to stare at the aircraft without blinking or never look at the controller. You may need to glance briefly at the controller or screen to check altitude, speed, battery status, or other flight information. During a close structural inspection, the aircraft may also briefly pass behind the edge of a roof.

If visual contact is briefly interrupted, restore VLOS as soon as practicable. A short interruption is not permission to plan a flight behind a building, terrain feature, or other obstruction where the aircraft remains out of sight.


Visual Observers

Using a Visual Observer (VO) is optional. When a VO is used, however, the VO must use unaided vision and the Remote PIC must ensure that the VO can see the aircraft in the manner required by the VLOS rule.

Remote PIC

The Remote PIC retains final authority and responsibility for the operation, including regulatory compliance and safe operation.

Person Manipulating the Controls

The person manipulating the controls coordinates with the Remote PIC and VO, if one is used, to scan for hazards and maintain awareness of the aircraft’s position.

Visual Observer

The Visual Observer helps observe the aircraft and airspace, reports hazards, and uses unaided vision to perform the VLOS function.

When a VO is used, the Remote PIC, the person manipulating the controls, and the VO must maintain effective communication at all times. They must also coordinate to scan the airspace for potential collision hazards and to maintain awareness of the aircraft’s position through direct visual observation.

A VO helps the operation, but does not remove the Remote PIC’s responsibility or final authority.


One Person, One Drone

Under Part 107, a person may not manipulate flight controls, serve as Remote PIC, or act as a Visual Observer for more than one unmanned-aircraft operation at the same time.

Memory aid: One person, one drone.


Automated Operations

Automation does not create a VLOS exception. A mapping grid, orbit, return-to-home function, or subject-tracking feature may help fly the aircraft, but the Remote PIC remains responsible for the operation.

The Remote PIC must still maintain the required visual awareness, yield to other aircraft when required, comply with all applicable rules, and retain the ability to direct the aircraft if something goes wrong.

Before starting an automated mission, confirm that the route can be conducted within VLOS, that communication and team roles are clear, and that the Remote PIC can intervene promptly if conditions change.


Preflight VLOS Checklist

  • The planned route remains within visual line of sight.
  • The Remote PIC can identify safe observation positions and likely obstructions.
  • If a VO is used, effective communication and hazard-callout procedures are established.
  • No team member is assigned to more than one simultaneous UAS operation.
  • An automated route can be monitored and redirected safely.


Lesson Recap

  1. Keep the aircraft in visual line of sight using unaided vision, except for corrective lenses.
  2. Maintain enough awareness to determine the aircraft’s location, attitude, altitude, direction, and potential hazards.
  3. A Visual Observer is optional but must use unaided vision and communicate effectively with the Remote PIC and person manipulating the controls.
  4. Automation does not reduce the Remote PIC’s responsibility.
  5. One person may perform only one UAS role at a time.

FAA Resources


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