Not sure what exactly are you looking for. Bunch of info is on FAA website, for example: https://www.faa.gov/air_traffic/publications/atpubs/aim_html/chap1_sec

Not sure what exactly are you looking for. Bunch of info is on FAA website, for example: https://www.faa.gov/air_traffic/publications/atpubs/aim_html/chap1_section_1.html https://www.faa.gov/air_traffic/publications/atpubs/aim_html... https://www.faa.gov/air_traffic/flight_info/aeronav/acf/media/Presentations/21-02-NavAid-Service-Volumes-Courtney.pdf https://www.faa.gov/air_traffic/flight_info/aeronav/acf/medi...