04/21/2017: U.S. Marines conduct an external lift during CH-53 Tactics in support of Weapons and Tactics Instructor (WTI) course 2-17 at Yuma, Ariz., 7 April, 2017. WTI is a seven-week training event hosted by MAWTS-1 cadre, which emphasizes operational integration of the six functions of Marine Corps aviation in support of…