UASFM stands for UAS Facilities Maps. These maps show grids overlaying controlled airspace around airports. Each grid has an altitude, decided upon by local Air Traffic Control (ATC). Flights at or below the height depicted in the grid are generally automatically approved, while flights above the height depicted in the grid are generally sent to ATC for further coordination to determine whether the proposed operation may safely take place. Find more information here: https://www.faa.gov/uas/commercial_operators/uas_facility_maps/
