An AGE-old procedure
U.S. Air Force Airman 1st Class Sarah Shaw, 20th Equipment Maintenance Squadron aerospace ground equipment apprentice, replaces the air filter on a self-generating nitrogen servicing cart. The cart is used to fill the tires of F-16CM Fighting Falcons, as well as add nitrogen to fuel lines for hydraulics. (U.S. Air Force photo by Airman 1st Class Kelsey Tucker)