Operational Visual Range
This operating condition requires the remote pilot or a visual observer to be able to see the unmanned aircraft throughout the flight with unaided vision, except for corrective lenses.
Visual Line of Sight (VLOS)
In a coordinated operation, this role holds final responsibility for the safety, regulatory compliance, and decision-making authority for the flight.
Pilot in Command (PIC)
This lighter-than-air craft remains aloft because its lifting gas is less dense than the surrounding air; balloons and airships are examples.
Aerostat
This reliability measure estimates the average operating time expected between failures of a repairable system or component.
Mean Time Between Failure (MTBF)
This term encompasses the United States' interconnected airspace, airports, navigation facilities, surveillance systems, aircraft, and personnel that support aviation operations.
National Airspace System (NAS)
$100: This person assists the remote pilot by maintaining visual awareness of the unmanned aircraft and surrounding airspace, but does not replace the remote pilot's responsibility for the operation.
Visual Observer (VO)
This term describes an arrangement in which flight-control responsibilities or operational functions are distributed between geographically separated locations.
Remote Split Operations (RSO)
This descriptor generally applies to aviation activity or platforms operating in the upper atmosphere, where environmental conditions and airspace considerations differ substantially from typical low-altitude flight.
High Altitude
This private, nonprofit organization develops consensus-based technical standards and guidance used in aviation, including standards relevant to avionics and UAS integration.
Radio Technical Commission for Aeronautics (RTCA)
This foundational collision-avoidance principle requires pilots to remain vigilant, scan for traffic and hazards, and take action when necessary to prevent a collision.
See and Avoid
This concept allows an unmanned aircraft to operate at a greater distance than ordinary VLOS when one or more observers are positioned to maintain visual contact and communicate with the remote pilot.
Extended Visual Line of Sight (EVLOS)
This observer is positioned away from the remote pilot's location to help provide visual surveillance or airspace awareness during a UAS operation.
Remote Visual Observer (RVO)
This aircraft is flown recreationally and is subject to statutory safety limitations, including the requirement that it be operated in accordance with a community-based organization's safety guidelines when applicable.
Model Aircraft
These standards define the minimum performance an aviation system must demonstrate to support a particular operational application safely and consistently.
Minimum Operating Performance Standards (MOPS)
This safety capability uses sensors, data, procedures, and/or automation to identify potential conflicts and enable an aircraft or operator to remain safely separated from other aircraft.
Detect and Avoid (DAA)
This term describes an operation in which the remote pilot cannot maintain direct visual contact with the unmanned aircraft and relies on an approved operational framework and risk mitigations.
Beyond Visual Line of Sight (BVLOS)
This FAA-issued credential signifies that an individual has met applicable knowledge, skill, and medical or certification requirements for a specified aviation privilege.
Airman Certificate
This federal regulation establishes the principal operating rules for non-recreational small unmanned aircraft operations in the United States.
14 CFR Part 107
This event occurs when the control-and-command connection between the unmanned aircraft and its control station is interrupted or unavailable.
Loss of Link
This surveillance technology broadcasts an aircraft's position and other information, typically using satellite-derived navigation data, so that properly equipped users and ground systems can receive it.
Automatic Dependant Surveillance Broadcast (ADS-B)
This broader term refers to an aircraft operation conducted beyond the operator's ability to see the aircraft directly; it may be used in manned or unmanned aviation contexts.
Beyond Line of Sight (BLOS)
This credential notation is associated with operating small unmanned aircraft systems and may be added to an eligible FAA certificate under applicable FAA procedures.
sUAS Endorsement
This FAA approval confirms that a particular aircraft design meets applicable airworthiness standards; production aircraft of that design may be manufactured under the approval framework.
Type Certificates
This programmed contingency function directs an unmanned aircraft to fly back to a predetermined recovery point, often after a specified trigger such as low battery or a lost command link.
Return-to-Home (RTH)
This operating requirement is met when the remote pilot or visual observer can maintain direct, unaided visual contact with the unmanned aircraft sufficiently to determine its location, attitude, direction, and potential hazards.
Visual Line of Sight (VLOS)