NASA的X-59超音速喷气机已获准进行最终组装
NASA的X-59实验飞机
可以使超音速商业旅行成为现实的东西，已经被最终组装。 X-59静音超音速技术（QueSST）飞机，
由洛克希德·马丁公司（Lockheed Martin）设计的飞机可能会在2021年首次试飞。
This is NASA’s first large-scale, piloted x-plane (or experimental aircraft) in more than three decades, and its goal is to reduce the loudness of a sonic boom to more of a sonic thump.
Engadget
https://www.engadget.com/2019/12/17/nasa-x59-supersonic-jet-assembly/