Familiarization flight
ALTUS AIR FORCE BASE, Okla. – A U.S. Air Force KC-135 Stratotanker refueling aircraft waits with its boom in position for a U.S. Air Force C-17 Globemaster III cargo aircraft to approach for refueling, Feb. 12, 2015. The 54th Air Refueling Squadron and the 58th Airlift Squadron train KC-135 and C-17 aircrews at Altus AFB, Okla. (U.S. Air Force photo by Airman 1st Class Nathan Clark/Released)