Chinese researchers have built a prototype hypersonic flight engine based on a design by NASA that was scrapped more than two decades ago.  The development comes months after the Chinese regime tested a nuclear-capable hypersonic missile that reportedly took U.S. intelligence by surprise.  In a peer-reviewed paper published Dec. 5 in China’s Journal of Propulsion Technology, a Chinese research team said that, thanks to a two-decade-old American design, they had developed and tested a prototype hypersonic flight engine. The team, led by Tan Huijun, a professor at Nanjing University of Aeronautics and Astronautics in eastern China’s Jiangsu Province, said in the paper the design by NASA attracted much attention among Chinese researchers, since “understanding its work mechanism can provide important guidance to hypersonic plane and engine development.” The American design was proposed by Tang Ming Han, a Chinese American, when he was the chief engineer of NASA’s High-Speed Research Program from 1996 …