U.S. successfully tests hypersonic missile that's five times … stocking 0 40 2021.09.28 11:14 https://youtu.be/SPl5U8PvO7U + 11 美국방부 "음속 5배 넘는 '극초음속 미사일' 시험발사 성공"- The U.S. has held a successful test-flight of a missile that's five times faster than the speed of sound.