Might the Department of Defense turn the F-47 fighter into a stealthier, sixth-generation F-35 with -A, -B, and -C models?The news struck defense stock investors like a missile from a clear blue sky:In March 2025, the U.S. Air Force announced that its first-ever sixth-generation fighter jet will be built not by Lockheed Martin (LMT -1.12%), the world's biggest pure-play defense contractor and the company that built both of America's last two fifth-generation fighter jets (the stealthy F-22 and F-35).Instead ...