Definition
The capability of an aircraft, particularly an unmanned aircraft system (UAS), to detect other aircraft or hazards in its flight path and take appropriate action to remain well clear and prevent a collision. Sense and Avoid serves as the technological and procedural equivalent of the see-and-avoid responsibility that pilots of manned aircraft fulfil visually under 14 CFR §91.113.
Plain English
The ability of a drone or other aircraft to notice nearby traffic and stay out of its way, the same way a pilot in a cockpit would look outside and steer clear of other aircraft.
Context Anchor
Seen in unmanned aircraft, traffic awareness, and collision-avoidance discussions.
Derivation
Sense' comes from the Latin sentire, meaning to perceive or detect. 'Avoid' comes from Old French esvuidier, meaning to empty out or get away from. Together the term simply names the two-step task: first detect the threat, then move clear of it. The phrase was coined as the unmanned-aircraft counterpart to the long-standing 'see and avoid' rule for manned flight.
Why Pilots Care
Allows drones to share airspace with manned aircraft while keeping collision risk acceptably low.
Analogy
Works like a car's automatic emergency braking that senses an obstacle and stops before impact.
Grounding Statement
If another aircraft is moving toward your path, SAA means detecting it soon enough to turn, climb, descend, slow, or otherwise stay safely away.
Intuition Check
Do not read Sense and Avoid as only “see and dodge.” In FAA use, “sense” can include visual observation, equipment, or other approved ways of detecting traffic, and “avoid” means taking timely action to remain safely clear.
Example Sentence 1
The UAS operator confirmed the aircraft's Sense and Avoid system was functional before launching the flight near the Class D airspace boundary.
Example Sentence 2
Future drone deliveries will rely on SAA systems to remain well clear of manned traffic.