65.31—Required certificates, and rating or qualification.
No person may act as an air traffic control tower operator at an air traffic control tower in connection with civil aircraft unless he—
(b)
Holds a facility rating for that control tower issued to him under this subpart, or has qualified for the operating position at which he acts and is under the supervision of the holder of a facility rating for that control tower; and
Code of Federal Regulations
(c)
Except for a person employed by the FAA or employed by, or on active duty with, the Department of the Air Force, Army, or Navy or the Coast Guard, holds at least a second-class medical certificate issued under part 67 of this chapter.