Staff Sgt. Edwin Martinez-Diaz observes an F-15 Eagle fighter jet engine to ensure the machine is properly rotating during an engine test at the 18th Component Maintenance Squadron engine test facility at Kadena Air Base, Japan, June 26, 2012. The facility, which is designed to house aircraft engines requiring maintenance and testing, is also used to greatly reduce the amount of noise impact on the local community. Diaz is an aerospace propulsion journeyman with the 18th CMS. (U.S. Air Force photo/Airman 1st Class Justin Veazie)