The F-16 Block 70/72 remains in productionbut only for export (the US Air Force no longer purchases F-16s). The F-16 has proven itself to be one of the most successful fighter jets ever made. It is a relatively small, capable, affordable, and versatile fighter jet that many middle or smaller air forces can afford to operate. Both new and second-hand F-16s remain in demand all around the world. In fact, Lockheed Martin says it currently has a backlog of 135 jets. Block 70/72 is the latest (and perhaps last) variant of the F-16 family and is night and day different from the original aircraft produced in the late 1970s and 1980s.