GRISSOM AIR RESERVE BASE, Ind. -- Senior Airman Matthew Devers, 434th Operations Support Squadron aircrew flight equipment apprentice, shows Boy Scouts from Troop 229 how to test an oxygen mask worn by aircrew prior to flight during a base tour July 25. The Boy Scouts visited Grissom to learn about the diverse jobs performed on base. (U.S. Air Force photo/Senior Airman Andrew McLaughlin)