Scott Meredith, left, technical advisor for Arnold Engineering Development Complex (AEDC) Flight Systems Branch, and Chief Master Sgt. Stanley Cadell, command chief, Air Force Materiel Command, walk past a rake installed in a test section of the 16-foot supersonic wind tunnel, which is used to characterize the flow in the tunnel, during a tour July 8, 2020, at Arnold Air Force Base, Tenn., headquarters of AEDC. The visit to the Base by Cadell and Gen. Arnold W. Bunch Jr., commander, Air Force Materiel Command, focused on COVID-19 response, and diversity and inclusion. (U.S. Air Force photo by Jill Pickett) (This image has been altered by obscuring a badge for security purposes.)