Airman 1st Class Joseph Geiger, 911th Aircraft Maintenance Squadron electrical and environmental systems technician, reads over the pneumatic systems standard operating procedure during maintenance of a C-17 engine at the Pittsburgh International Airport Air Reserve Station, Pennsylvania, Oct. 29, 2019. The SOP explains where parts are located, what they do and how these parts should be functioning when operating correctly. (U.S. Air Force photo by Joshua J. Seybert)