B-1B crew chief
U.S. Air Force Senior Airman Jordan Duncan, 379th Expeditionary Aircraft Maintenance Squadron B-1B crew chief, marshals a B-1B Lancer prior to takeoff at Al Udeid Air Base, Qatar, July 8, 2014. Crew chiefs are responsible for ensuring the aircraft are inspected and have functional checks completed as well as making sure the aircraft has been serviced with fuel, hydraulic fluid and liquid oxygen. Duncan is deployed from Ellsworth Air Force Base, South Dakota. (U.S. Air Force photo by Staff Sgt. Ciara Wymbs)