Complex sentence: Pilots can find RCO frequencies in charts or the Canada Flight Supplement, then make a radio call to the outlet as if they were making the call directly to the FSS or FIC.
Split into simpler sentences: Pilots can find RCO frequencies in charts or publications such as the Canada Flight Supplement. The RCO is used to make a radio call to the outlet as if the pilot were making the call directly to the FSS or FIC.