In the lead up to the flight test phase of a major F-35 technology refresh, the joint program office and Lockheed Martin are closely tracking schedule risk and have developed a slate of trade-off options should the effort face additional delays over the next year. Technology Refresh 3 is a key F-35 hardware and software upgrade required before the program can integrate most of the planned Block 4 modernization capabilities. However, TR-3 costs have grown by about $444 million since...