Senior Airman Kawika Hasson, 911th Aircraft Maintenance Squadron electrical and environmental systems technician, replaces a pressure regulator valve on a C-17 engine at the Pittsburgh International Airport Air Reserve Station, Pennsylvania, Oct. 19, 2019. This valve regulates air pressure within the engine preventing it from going over temperature or over pressurizing protect other components inside the engine. (U.S. Air Force photo by Joshua J. Seybert)