Air Force Reserve and Air National Guard Explained The Air Force Reserve (AFRES) is a federal reserve component of the U.S. Air Force. The Air National Guard (ANG) is the air militia component of the National Guard of each state or territory (with each state's ANG under the jurisdiction of that state's governor). AFRES and ANG units can be mobilized for active duty with the USAF by presidential order. ANG units can also be mobilized by their governors for state service in a crisis such as a natural disaster. Click here to return to the AFRES/ANG Overview.