A U.S. Air Force F-35A Lightning II from Eglin Air Force Base, Florida, taxies down the flight line before takeoff at Tyndall Air Force Base, Florida, in December 2016. The high lifetime and per-unit costs of the fifth-generation fighter plane have drawn criticism from many, including the Trump administration. Each aircraft in the most recent batch cost less than $100 million, however, the first time that the aircraft’s unit cost has dropped below that threshold. (Photo by U.S. Air Force Staff Sgt. Alex Fox Echols III)