Few pilots flying today would turn their backs on the aviation advances made possible by digital communication, navigation, and surveillance (CNS) avionics. Newer aviators grew up in the GPS generation, so really know nothing else. And for the VOR generation of pilots, maybe it has been so long that they take technology’s benefits for granted. But in either case, all the wonderful stuff modern CNS equipment does to make an aviator’s life easier comes with responsibilities. First among them is using the correct CNS capability code on every flight plan, so ATC can employ the proper separation standards and keep everyone safe.
Some may say that they always provide the proper CNS code, and this may well be the case with you. But it is not universal, which is why the FAA issued Information for Operators (InFO) 16015. “The Federal Aviation Administration continues to experience operators/pilots filing the incorrect CNS codes due to aircraft system deferrals, aircraft not properly equipped or approved, or pilots not qualified for CNS capability on the FPL [Flight Plan Filing]. Given the congested Chicagoland airspace, making sure your aircraft is properly equipped and approved, and that you are properly trained and qualified on that equipment, and that you use appropriate CNS code on every flight plan makes life easier, more efficient—and safer—for all who share the sky.
All of this became especially important in November 2012 when the FAA harmonized its flight plan with the International Civil Aviation Organization flight plan box 10, Equipment & Capabilities, and box 18, Other Information such as RNAV and Performance-Based Navigation (PBN) capabilities. To make sure you are employing the right CNS codes you can start with the handy FAA ICAO FPL Quick Guide. To get deeper into the topic, see FAA Operations Specifications/LOA [Letter of Authorization]/Approvals Required to File Various Capabilities. It is an overview and portal with links to the related regs and requirements.