Edgar G Obie Airport frequencies

Edgar G Obie Airport (S71) in Chinook, MT has no control tower, so nobody is sequencing traffic here — you announce your own position on 122.8. Every frequency below is in the order you tune it. · Open on the map

All of Edgar G Obie Airport — runways, frequencies, charts and live weather

Before taxi

ASOS/AWOS 118.35
An automated weather station reading the field conditions aloud — wind, visibility, ceiling, temperature and altimeter. It replaces ATIS at a field with no controller to record one. Get the altimeter setting before you descend below the transition altitude.

Taxi & takeoff

CTAF 122.8
The common frequency pilots use to announce themselves to each other at a field with no operating control tower. Nobody is controlling traffic — you are self announcing. Report your position and intentions on entry and on each leg of the pattern, and listen well before you transmit.
UNICOM 122.8
A ground station run by the FBO rather than the FAA, for fuel, parking and airport services. Use it for services. Where the field has no separate CTAF, the same frequency doubles as the advisory frequency.

What to say on 122.8

Nobody is sequencing traffic at S71, so every call is you telling other aircraft where you are. Open and close with the field name so a pilot tuned to a shared frequency knows which airport you mean — 122.8 is not unique to Edgar G Obie Airport.

  • Inbound, 10 miles out Edgar G Obie traffic, Skyhawk one two three four five, one zero miles south, inbound landing runway 08, Edgar G Obie.
  • Entering the pattern Edgar G Obie traffic, Skyhawk one two three four five, entering left downwind runway 08, Edgar G Obie.
  • Before taking the runway Edgar G Obie traffic, Skyhawk one two three four five, departing runway 08, Edgar G Obie.

Pattern direction is not always left here — check the S71 traffic pattern before you announce a leg. The Chart Supplement is authoritative if S71 publishes a call name that differs from the airport's. Full guidance →

Every S71 frequency, as one table
ASOS/AWOS118.35
CTAF122.8
UNICOM122.8

Frequently asked

What is the CTAF at S71?

Edgar G Obie Airport is non towered. The common traffic advisory frequency is 122.8 — announce your position and intentions on entry and on each leg of the pattern.

What is the ASOS/AWOS frequency at S71?

ASOS/AWOS at Edgar G Obie Airport is 118.35. It is an automated broadcast, so there is no letter to report — just take the altimeter setting and wind.