PA.VI.B.K4FAA-S-ACS-6C · Nov 2023Knowledge
Transponder (Mode(s) A, C, and S) and Automatic Dependent Surveillance-Broadcast (ADS-B).
Transponder (Mode(s) A, C, and S) and Automatic Dependent Surveillance-Broadcast (ADS-B).
Bottom line
The ADS-B cockpit display of traffic is NOT intended to be used as a collision avoidance system and does not relieve the pilot’s responsibility to “see and avoid” other aircraft.
Key numbers
| Number | What it means |
|---|---|
| 18,000 feet and above (Class A airspace) requires 1090ES equipment | Class A equip |
| Operators that do not fly above 18,000 feet may use either UAT or 1090ES equipment | Below 18,000 |
| 978 or 1090 MHz | ADS-B links |
| Maximum of seven alphanumeric characters | FLT ID length |
| Approximately once per second | Position rate |
FAA references
- AFH Glossary (p. G-15) — FAA-H-8083-3C
- AIM 4-5-7 (Automatic Dependent Surveillance-Broadcast (ADS-B) Services) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
- PHAK ch. 14 (p. 14-24) — FAA-H-8083-25C (2023)
- AIM 4-5-10 (Automatic Dependent Surveillance-Rebroadcast (ADS-R)) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
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