Lockheed F-35A fighter model. Commonality and flexibility are the basis for the Lockheed Martin JSF design. The high degree of commonality among the service aircraft variants, and across the total development and production program, is a key to affordability. Cooperation allows the participating services to share development costs, which in turn greatly reduces total cost, when compared to an independent program for each service. Together, the services plan to purchase approximately 3,000 aircraft, so this highly common design will benefit from economies of scale. Additional international sales of approximately 2000 JSFs may further reduce costs.