Definition
The receiving function of the ADS-B system, in which an aircraft equipped with an ADS-B In receiver picks up broadcast position, velocity, and identification data transmitted by other ADS-B Out equipped aircraft, as well as ground-uplinked traffic and weather services such as TIS-B (Traffic Information Service–Broadcast) and FIS-B (Flight Information Service–Broadcast). The received information is displayed in the cockpit to improve situational awareness.
Plain English
Equipment in your aircraft that listens for position reports being broadcast by other aircraft and by ground stations, then shows that traffic and weather information to you on a cockpit display.
Context Anchor
Seen in cockpit display, traffic awareness, weather display, and ADS-B equipment discussions.
Derivation
Automatic — happens without pilot action. Dependent — depends on the aircraft's own GPS data being broadcast (rather than being independently measured by a radar). Surveillance — the act of watching where aircraft are. Broadcast — sent out openly for anyone to receive. In — this is the receive side, as opposed to ADS-B Out, which is the transmit side.
Why Pilots Care
Improves situational awareness and helps avoid traffic conflicts by showing nearby aircraft positions in real time.
Grounding Statement
With ADS-B In, your aircraft is listening for useful broadcast information and showing it to you in the cockpit.
Intuition Check
“In” does not mean an inbound flight or an approach direction here. It means data is being received into the aircraft; sending your own aircraft information is a separate function.
Example Sentence 1
With ADS-B In installed, the pilot saw nearby traffic appear on the cockpit display well before ATC issued a traffic advisory.
Example Sentence 2
Automatic Dependent Surveillance–Broadcast In allowed the pilot to monitor nearby aircraft altitudes during the cross-country flight.