Soldiers with 1st Battalion, 1st Air Defense Artillery

Soldiers with 1st Battalion, 1st Air Defense Artillery Regiment, rehearse battle drills with the PATRIOT long-range, all-altitude, all-weather air defense system capable of countering tactical ballistic missiles, cruise missiles and advanced aircrafts to enhance crew-drill proficiency during Keen Sword/Orient Shield 21 at Misawa Air Base Oct. 28. KS/OS 21 is a joint expeditionary bilateral exercise, which allows Japan Self-Defense Forces and U.S. military forces to work together across a variety of areas, enhancing the interoperability of U.S. and Japan forces.