The United States Air Force does not have a First Sergeant rank. It is instead a duty denoted by a diamond within the upper field. They usually act in the capacity of as a pulse of the morale and welfare of the unit to the Commander. The Chief Master Sergeant of the unit is the Senior Enlisted Advisor to the unit commander.
Only one individual was awarded the rank of General of the Air Force, semi-retroactively. General of the Army "Hap" Arnold was awarded the rank in 1949, two years after the establishment of the United States Air Force as a separate body from the United States Army. General Arnold was considered inactive at this time [although not retired, as five-star generals do not officially retire from service], so this rank has never been awarded to an officer of the modern USAF while on active duty.