In the early 2000s, NASA was among the first to achieve sustained hypersonic flight. As part of the broader Hyper-X program, NASA developed the X-43, a small, unmanned research aircraft powered by an experimental scramjet. From 2001 to 2004, X-43A conducted three test flights, with the third proving particularly successful. Originally, there were plans to produce more test aircraft and develop variants of the X-43A, but these were later scrapped…