CA.II.E.K6bFAA-S-ACS-7B · Nov 2023Knowledge
b. Radio communications at towered and nontowered seaplane bases
Procedures for: b. Radio communications at towered and nontowered seaplane bases
Bottom line
Pilots operating from a towered airport are required to maintain two-way radio communication with ATC and to acknowledge and comply with their instructions. The key to communicating at an airport without an operating control tower is selection of the correct common frequency.
Key numbers
| Number | What it means |
|---|---|
| 122.9, where there is no tower, FSS, or UNICOM station on the airport | MULTICOM |
| 10 miles to landing | Inbound CTAF |
| 8 to 10 miles from the airport | Straight-in call |
| 122.7, 122.8, 122.725, 122.975, or 123.0 | UNICOM CTAF |
FAA references
- PHAK ch. 14 (p. 14-2) — FAA-H-8083-25C (2023)
- AIM 4-1-9 (Traffic Advisory Practices at Airports Without Operating Control Towers) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
- AIM 4-1-5 (Communications Release of IFR Aircraft Landing at an Airport Without an Operating Control Tower) — AIM Basic 2/20/25 w/ Change 1 (8/7/25) & Change 2 (1/22/26)
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