Osan Airmen train, compete in Jiu-jitsu tournament

Osan Air Base, Republic of Korea -- U.S. Air Force Staff Sgt. Christopher Costa, 51st Communications Squadron radio frequencies transmissions systems supervisor, observes his students practicing Brazilian jiu-jitsu at Osan Air Base, Republic of Korea, Nov. 21, 2016. Costa teaches jiu-jitsu to team Osan members on-base during his off-duty hours. (U.S. Air Force photo by Staff Sgt. Jonathan Steffen)