AA.II.D.K7bFAA-S-ACS-11A · Nov 2023Knowledge
b. Communications at towered and nontowered seaplane bases
Airport/seaplane base procedures, including: b. Communications at towered and nontowered seaplane bases
Bottom line
Unless otherwise authorized or required by ATC, no person may operate an aircraft to, from, through, or on an airport having an operational control tower unless two-way radio communications are maintained between that aircraft and the control tower. The common frequency used by airport traffic to announce position reports in the vicinity of the airport. The absence of an operating airport control tower creates a need for increased vigilance on the part of pilots operating at those airports.
Key numbers
| Number | What it means |
|---|---|
| 4 NM / 2,500 ft AGL | Towered comms |
FAA references
- 14 CFR 91.127 (Operating on or in the vicinity of an airport in Class E airspace.) — eCFR current as of 2026-03-05
- AFH Glossary (p. G-4) — FAA-H-8083-3C
- AFH ch. 1 (p. 1-13) — FAA-H-8083-3C
- 14 CFR 91.129 (Operations in Class D airspace.) — eCFR current as of 2026-03-05
- SEA ch. 6 (p. 6-1) — FAA-H-8083-23
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