Radio calls at a nontowered airport

Every self announce call has the same four parts, in the same order: the airport you are calling, who you are, where you are, and what you intend to do. Then you say the airport name once more at the end, because that is the only word that tells everyone else on a shared frequency whether the call was meant for them.

Roughly nine in ten US public use airports have no control tower: 4,690 of the 5,255 in the FAA's own facility data. Nobody is sequencing you, nobody is issuing clearances, and separation is yours under see and avoid. The radio is how a group of strangers builds a shared picture, and it only works if everyone uses the same shape.

Which frequency

Use the CTAF, the common traffic advisory frequency published for that airport. It is printed on the sectional next to the airport name with a filled circle after it, and it is on every SkyReady airport page.

Three words get used loosely and mean different things:

• CTAF is the role, not a specific number. It is whichever frequency has been designated for self announce at that field. At a part time tower it is usually the tower frequency when the tower is closed.
• UNICOM is a ground station, typically the FBO. It answers requests for fuel, a courtesy car or an advisory. At many fields the UNICOM frequency is also the CTAF, which is why the two get confused. A UNICOM advisory is information, not an instruction.
• MULTICOM 122.9 is the fallback when an airport has no published CTAF or UNICOM at all.

Find the number before you need it. Each airport's frequencies page lists CTAF, UNICOM, ATIS or AWOS and the approach and departure sectors, and the printable kneeboard puts them on one sheet.

The four part call

Use the aircraft type and the last three to five characters of the registration, not the full N number. "Skyhawk 345" is more useful to another pilot than "November eight two seven four five", because type tells them roughly how fast you are closing.

The six calls in a normal arrival

1. Ten miles out. "Livermore traffic, Skyhawk 345, one zero miles south, inbound for landing, Livermore."
2. Entering downwind. "Livermore traffic, Skyhawk 345, entering left downwind runway two five right, Livermore."
3. Downwind. Abeam the numbers. Useful when there is traffic behind you.
4. Base. "Livermore traffic, Skyhawk 345, left base runway two five right, Livermore."
5. Final. "Livermore traffic, Skyhawk 345, final runway two five right, Livermore."
6. Clear of the runway. Short, and it matters: it releases the runway for everyone still listening.

Departing, it is two calls: one before you taxi or as you approach the runway, and one as you depart, stating your direction. "Livermore traffic, Skyhawk 345, departing runway two five right, northbound, Livermore."

Which downwind you enter is not a free choice. Most patterns are left, but a meaningful minority of runway ends are charted right traffic, and the pattern entry is a separate skill from the radio call. Our guide on entering the pattern at a nontowered airport covers the geometry, and we mapped every charted right traffic pattern in the US.

Habits to drop

1. "Any traffic in the area please advise." The AIM specifically asks pilots not to use it. It invites several aircraft to transmit at once, which blocks the frequency at the moment it is busiest. Announce your own position instead and listen.
2. Leaving the airport name off the end. Adjacent fields share frequencies constantly, and 122.9 is shared nationwide. Without the trailing name a listener cannot tell whether you are three miles from them or thirty.
3. "Taking the active." There is no active runway without a tower. There is the runway you have chosen. Say which one.
4. Reciting the full N number every call. Correct on first contact with ATC, unhelpful on a busy CTAF. Type plus the last three is faster and more useful.
5. Assuming the radio is doing the work. No radio is required at most nontowered fields, so aircraft without one are legal and present. Right of way under 14 CFR 91.113 does not depend on who transmitted.

When the tower is open

A part time tower changes the whole procedure. With the tower open you need a clearance to enter the pattern or the surface area, and the sequence is ATIS, then ground for taxi, then tower. When it closes, that same frequency becomes the CTAF and you go back to self announcing. The airport's frequencies page lists the tower hours alongside the numbers, and it is worth checking whether your arrival lands on the right side of that transition.

Radio FAQ

What does CTAF stand for?

Common traffic advisory frequency. It is the designated frequency for carrying out airport advisory practices while operating to or from an airport without an operating control tower.

Is a radio required at a nontowered airport?

Generally no. Most nontowered fields have no radio requirement, which is exactly why see and avoid remains the primary means of separation. Class E surface areas and airports underlying certain airspace have their own rules, so check the airspace, not just the airport.

What if the airport has no published CTAF?

Use MULTICOM 122.9 and self announce as normal. Say the airport name clearly at the start and end of every call, because 122.9 is shared across the country.

Who am I talking to on UNICOM?

Usually an FBO employee, not a controller and not a weather observer. They can give you the runway in use, the wind and airport advisories, and arrange fuel or transport. Everything they say is advisory. The decision stays with you.

Sources: AIM 4-1-9 (Traffic Advisory Practices at Airports Without Operating Control Towers); AC 90-66C; 14 CFR 91.113 and 91.126. Educational material; confirm procedures for the specific airport before you fly.