Lire
http://psk.blog.24heures.ch/archive/2018/01/03/le-su-57-teste-ses-moteurs-definitifs-864977.html
https://thediplomat.com/2017/12/russias-su-57-stealth-fighter-makes-maiden-flight-new-engine/
https://en.wikipedia.org/wiki/Saturn_AL-31
https://en.wikipedia.org/wiki/Saturn_AL-41
