U.S. Air Force Senior Airman Joel Castillo, 31st Aircraft Maintenance Squadron crew chief, sits on the flightline at Graf Ignatievo Air Base, Bulgaria, Sept. 28, 2020. Catillo performed a hot preflight during NATO’s enhanced Air Policing Allied mission. One of NATO’s roles is to preserve the integrity of Allied airspace, and during eAP the alert teams performed a hot preflight to minimize the amount it takes to launch an aircraft. (U.S. Air Force photo by Airman 1st Class Ericka A. Woolever)