U.S. Air Force Tech. Sgt. Dan Sohnrey, an engine mechanic with the 180th Fighter Wing, uses a borescope to inspect the inside an F-16 Fighting Falcon with the assistance of crew chief, Staff Sgt. Michael Woronec, , at the Alpena Combat Readiness Training Center in Alpena, Michigan, Aug. 21, 2014. The 180th Fighter Wing deployed to the CRTC to participate Operation Northern Strike, a joint exercise led by the National Guard that demonstrates the combined power of the air and ground forces. (Air National Guard photo by Staff Sgt. Amber Williams/Released)