There are about 400 KC-135s in the Air Force inventory today, including those in active duty, in the Air Force Reserve, and in the Air National Guard. The Air Force says it last took delivery of a KC-135 in 1965, but the venerable aircraft have had their share of modifications and updates over the years in areas ranging from the engines to navigation and surveillance systems. In this photo from 2011, a pilot runs through preflight checks in KC-135 based in Southwest Asia.
August 25, 2013 9:14 AM PDT
Photo by: US Air Force photo/Master Sgt. William Greer