Wednesday, December 19, 2018
Transport Canada - Aviation Safety Letter Accessing Flight Information Services via the RCO System Issue 2/2010

Accessing Flight Information Services via the RCO System Issue 2/2010

by Rob Bishop, Service Analyst, Level of Service and Aeronautical Studies, NAV CANADA

In 2005, NAV CANADA announced a plan—highlighted in AIP Canada (ICAO) Aeronautical Information Circular (AIC) 23/05—to address longstanding problems with the remote communications outlet (RCO) system. The plan, known as the RCO Redesign, involves changes in many areas of the country that affect how pilots access flight information services from flight information centres (FIC) while en route. Changes include the use of new, dedicated flight information service en route (FISE) RCO frequencies as well as the addition of new RCOs in some areas and the decommissioning of others to address coverage gaps or overlaps.

One of the RCO Redesign’s key safety goals is to reduce the current congestion and interference problems resulting from the FIC’s provisions of FISE and other services on 126.7 MHz. By using alternate FISE frequencies, pilots are now able to use 126.7 MHz more effectively in its primary function—as an air-to-air frequency for pilots to broadcast their intentions and their aircraft’s position—thereby reducing the risk of conflict when conducting VFR and IFR flights in uncontrolled airspace.

Currently, five primary frequencies are used to provide FISE: 122.37(5) MHz, 123.27(5) MHz, 123.37(5) MHz, 123.47(5) MHz, and 123.55 MHz. Other frequencies are sometimes used in instances where the primary ones are not compatible with the site. In some areas where frequency congestion is not an issue, 126.7 MHz will continue to be used by the FIC for FISE, safety message broadcasts and communication searches in addition to fulfilling its primary role of air-to-air communication.

Our experience with introducing the new FISE frequencies indicates that many pilots believe their radios are not capable of using the FISE frequencies published with three digits after the decimal. This is not the case for 760-channel radios. If the second position after the decimal can be tuned to a 2 or 7, then the radio can access frequencies with 25 KHz spacing (e.g. 123.37 = 123.375 MHz). For more information, refer to section COM 5.3 of the Transport Canada Aeronautical Information Manual (TC AIM).

While FICs no longer use or monitor 126.7 MHz in most areas of the country, they are capable of selecting 126.7 MHz, when required, to provide aeronautical broadcast service (significant meteorological information [SIGMET] and urgent pilot weather reports [PIREP]) and to conduct communication searches for overdue aircraft. This feature is indicated in aeronautical publications as 126.7 (bcst).

As changes are made, it is important to know where to find the most up-to-date information. Since changes reflected in aeronautical publications that are on the 56-day revision cycle are no longer published by NOTAM, pilots must use the following sources to obtain the correct FISE frequencies:

  • The current edition of the Canada Flight Supplement (CFS) under the following FIC entries: Halifax, Québec, London, Winnipeg, Edmonton, Pacific Radio (Kamloops FIC), Whitehorse, and Arctic Radio (North Bay FIC);

  • Notices published 60 days in advance of a change. These can be found under Notice on NAV CANADA’s Web site ( or on NAV CANADA’s aviation weather Web site ( via the NOTICES link; and

  • NAV CANADA’s Web site (click on Services, ANS Programs, then RCO Redesign). This site includes a brochure that describes the RCO Redesign project as well as current RCO maps for each FIC area. These maps are kept up to date as changes occur.

The redesign of the RCO system is reducing frequency congestion and allowing pilots to have better access to the services and information they need, while freeing up 126.7 MHz for its essential safety function. The project involves over 180 RCO sites and, to date, half of the sites have been completed. With changes occurring every two months, pilots must be vigilant to ensure they have the correct FISE frequencies for accessing the en route services and information they need to conduct their flight.

Have you checked NOTAMs?