Air Expeditionary Wings/Groups (AEW/AEG) are a Wing/Group concept used by the United States Air Force. These units are activated under temporary orders by the owning MAJCOM for a specific purpose or mission. Once the subject mission is completed, these units are inactivated.
A good source for some of these units appears to be the annual review issue of Air Force magazine.
References
List of Air Expeditionary units of the United States Air Force Wikipedia(Text) CC BY-SA