Senior Airman Jacob Scheffler, 80th Aircraft Maintenance Unit electrical and environmental systems journeyman, tightens a bolt to conduct a bleed air ops check on an F-16 Fighting Falcon at Kunsan Air Base, Republic of Korea, Nov. 6, 2020. A bleed air ops check tests air pressure at different points on the jet to verify that the engine swaps over from high-stage to low-stage pressure, and to make sure proper airflow is getting to the cockpit and avionics equipment. (U.S. Air Force Photo by Senior Airman Jessica Blair)