http://psk.blog.24heures.ch/archive/2020/06/14/vol-supersonique-silencieux-le-x-59-en-preparation-869363.html
https://fr.wikipedia.org/wiki/Lockheed_Martin_X-59_QueSST
https://www.nasa.gov/press-release/nasa-s-x-59-quiet-supersonic-research-aircraft-cleared-for-final-assembly
