YORKTOWN, Va. - From inside specially designed training bays, students of the Machinery Technician "A" Course learn engine repair at Coast Guard Training Center Yorktown, Nov. 13, 2012. During the intensive 13-week course, students learn the principles of theory, operation, maintenance, repair and troubleshooting of mechanical, auxiliary, hydraulic, pneumatic, and electrical machinery and systems. U.S. Coast Guard photo by Petty Officer 2nd Class Etta Smith