Methinks you don’t know what you are talking about. The FAA operates in feet. All domestic flights in the US are separated by flight levels specified in feet. If you get your pilots license in America, everything about it from runway length, controlled flight altitudes, wing spans, etc, will be in feet.
https://www.faa.gov/air_traffic/publications/atpubs/atc_html/chap4_section_5.html
Methinks you don’t know what you are talking about. The FAA operates in feet. All domestic flights in the US are separated by flight levels specified in feet. If you get your pilots license in America, everything about it from runway length, controlled flight altitudes, wing spans, etc, will be in feet.
For another example, just let me know how many metric units are used here: https://www.faa.gov/air_traffic/publications/atpubs/atc_html/chap3_section_10.html