N661FS is taken. It's currently assigned to a 1984 Sikorsky UH-60A registered in Cheyenne, WY.
See the full aircraft record →Checked against FAA data from Aug 23, 2026. Not an official FAA determination — always confirm with the FAA before filing.
A tail number only frees up if the owner deregisters the aircraft or moves it to a different N-number — and even then the FAA holds it before releasing it to the public.
Tails one nudge away from N661FS that aren't assigned or reserved: