N111 is taken. It's currently assigned to a 2015 Gulfstream Aerospace GV-SP (G550) registered in Los Angeles, CA.
See the full aircraft record →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.
N111 has been worn before. Past registrations from FAA deregistration records: