Articles

The Right Frequency

Getting Our Frequencies Straight!

by Brigitte Ouellet, Regional System Safety Specialist, Quebec Region

Most of the time, selecting the right frequency is pretty straightforward. We refer to the Canada Flight Supplement (CFS) and Canada Air Pilot (CAP), or we just use the frequency assigned by ATC. But have you ever asked someone whose voice you recognized on the air to select frequency 123.4 MHz? And have you ever noticed that there were a lot of NORDO aircraft in the circuit? Or perhaps you’ve used 126.7 MHz at an aerodrome not published in the CFS? These are only a few examples of frequencies being used incorrectly. Selecting the right frequency is not only essential to aviation safety, it also shows good airmanship.

Many incidents and accidents happen because pilots didn’t use their radio when they should have done, or they used the wrong frequency. Here are some figures that may surprise you: From 1995 to 1998, 39 percent of the "reported" near misses occurred because someone used the wrong frequency or did not use their radio when they should have. Evasive action was required in most cases. Twenty-nine percent of "reported" infractions involved failure to notify intentions when it was mandatory (MF communication zones and control zones). Also, many runway incursions that necessitated a go-around were the result of someone failing to advise their intentions.

Before going any further, let’s test your knowledge! Enter the following frequencies in the space below that describes their correct use: 121.5; 122.75; 123.2; 126.7; 131.8; 123.4.

You’ll find the answers in A.I.P. Canada, COM chapter 5.

Air-to-air in Northern Domestic Airspace: _________

Emergency: _________

Communication zone with no published frequency: _________

Air-to-air in Southern Domestic Airspace: _________

Gliding: ________

En route in uncontrolled airspace: _________

Using 123.4 MHz (reserved for soaring operations) as an air-to-air channel can cause problems in some areas. Glider pilots are constantly chatting on the air, passing on information about conditions or just telling other gliders how their flight is going. Also, on cross-country flights, they use 123.4 MHz to notify other aircraft of their position or any changes in their route. So you should select this frequency only when traversing a glider area so you’ll be aware of the traffic around you.

If you are not in contact with ATC or if you are not flying in an MF or ATF communication zone, you should be on 126.7 MHz. By monitoring this frequency en route, you’ll receive all position reports, both official (to the FSS) and unofficial, given by other pilots. Also, when you send your official position report, the FSS specialist will call back with the known traffic in your area and other information pertinent to your flight, like PIREPs, weather and SIGMETs.

Many pilots flying in northwestern Ontario use 122.8 MHz for en route use instead of 126.7 MHz. So pilots who select 122.8 MHz can’t receive the traffic information provided by pilots on 126.7 MHz.

It is essential that pilots select the proper frequency when flying in an ATF or MF communication zone. But you won’t know the right frequencies for these areas unless you consult relevant and up-to-date publications. When the frequency assigned to a communication zone is changed, a NOTAM is published. As soon as the publications are updated, the NOTAM is cancelled.

Your eyes are the best "instrument" for maintaining separation with other aircraft, but your radio is a close second. Remember: if they can hear you, they’ll find it easier to see you.

Have a good flight!