Since 2014, GAO has made 43 recommendations designed to improve the department’s operation and sustainment of the F-35 program. While DOD concurred with many of these recommendations and has implemented some of them, 30 (about 70 percent) remain unimplemented. For example, DOD has not implemented GAO’s recommendations that it update the sustainment strategy for the F-35 engine, improve the program’s management of spare parts, and reassess government and contractor responsibility for different aspects of F-35 sustainment.
