U.S. Air Force Maj. David Smith, a flight surgeon with the 36th Mobility Response Squadron at Andersen Air Force Base, demonstrates the use of medical care equipment to members of the Vietnamese Air Defense Air Force during a subject matter exchange on medical aspects for water survival as part of Pacific Angel (PACANGEL) 17-2 in Hanoi, Vietnam, Sept. 6, 2017. Now entering its 10th year, Operation PACANGEL ensures that the region’s militaries are prepared to work together to address humanitarian crises. (U.S. Air Force photo)