The Federal Communications Commission (FCC) seeks comments on proposed changes to frequency rules covering advanced air mobility (AAM) and uncrewed aerial systems (UAS). First, the FCC proposes opening up the 450 MHz band to UAS command and control operations; allowing for a single, nationwide license in the band; and adopting flexible licensing, operating, and technical rules that will facilitate robust use of the band while minimizing interference to neighboring operations. The agency also proposes expanding radiolocation operations in the 24.45–24.65 GHz band for UAS detection operations. Finally, the FCC proposes to modernize its legacy power regulations for aviation air-ground systems in the 849–851 and 894–896 MHz band, which are used for airborne connectivity. Comments are first due by April 16, 2025, and reply comments by May 16, 2025.